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Bronchiectasis
Figure A shows a cross-section of the lungs with normal airways and widened airways. Figure B shows a cross-section of a normal airway. Figure C shows a cross-section of an airway with bronchiectasis.
Pronunciation
SpecialtyPulmonology
SymptomsProductive cough, shortness of breath, chest pain[2][3]
Usual onsetGradual[4]
DurationLong term[5]
CausesInfections, cystic fibrosis, other genetic conditions, idiopathic[3][6]
Diagnostic methodBased on symptoms, CT scan[7]
Differential diagnosisChronic obstructive pulmonary disease, Asbestosis, Tracheobronchomalacia
TreatmentAntibiotics, bronchodilators, lung transplant[3][8][9]
Frequency1–250 per 250,000 adults[10]

Bronchiectasis is a disease in which there is permanent enlargement of parts of the airways of the lung.[5] Symptoms typically include a chronic cough with mucus production.[3] Other symptoms include shortness of breath, coughing up blood, and chest pain.[2] Wheezing and nail clubbing may also occur.[2] Those with the disease often get lung infections.[8]

Bronchiectasis may result from a number of infectious and acquired causes, including measles,[11] pneumonia, tuberculosis, immune system problems, as well as the genetic disorder cystic fibrosis.[12][3][13] Cystic fibrosis eventually results in severe bronchiectasis in nearly all cases.[14] The cause in 10–50% of those without cystic fibrosis is unknown.[3] The mechanism of disease is breakdown of the airways due to an excessive inflammatory response.[3] Involved airways (bronchi) become enlarged and thus less able to clear secretions.[3] These secretions increase the amount of bacteria in the lungs, resulting in airway blockage and further breakdown of the airways.[3] It is classified as an obstructive lung disease, along with chronic obstructive pulmonary disease and asthma.[15] The diagnosis is suspected based on symptoms and confirmed using computed tomography.[7] Cultures of the mucus produced may be useful to determine treatment in those who have acute worsening and at least once a year.[7]

Periods of worsening may occur due to infection.[8] In these cases, antibiotics are recommended.[8] Common antibiotics used include amoxicillin, erythromycin, or doxycycline.[16] Antibiotics, such as erythromycin, may also be used to prevent worsening of disease.[3][17] Airway clearance techniques, a type of physical therapy, are also recommended.[18] Medications to dilate the airways and inhaled steroids may be used during sudden worsening, but there are no studies to determine effectiveness.[3][19] There are also no studies on the use of inhaled steroids in children.[19] Surgery, while commonly done, has not been well studied.[20][3] Lung transplantation may be an option in those with very severe disease.[9]

The disease affects between 1 per 1000 and 1 per 250,000 adults.[10] The disease is more common in women and increases as people age.[3] It became less common since the 1950s with the introduction of antibiotics.[10] It is more common among certain ethnic groups (such as indigenous people in the US).[10] It was first described by René Laennec in 1819.[3] The economic costs in the United States are estimated at $630 million per year.[3]

Signs and symptoms

[edit]
The typical symptoms of bronchiectasis are shown. Also, the change in bronchi under bronchiectasis are illustrated.

Symptoms of bronchiectasis commonly include a cough productive of frequent green or yellow sputum lasting months to years.[3] Other common symptoms include difficulty breathing, wheezing (a whistling sound when you breathe), and chest pain. Exacerbations of symptoms may occur; these exacerbations occur more frequently in advanced or severe disease.[21] Systemic symptoms, including fevers, chills, night sweats, fatigue and weight loss may be seen with bronchiectasis.[21] Bronchiectasis may also present with coughing up blood in the absence of sputum, which has been called "dry bronchiectasis."

Exacerbations in bronchiectasis present as a worsening of cough, increasing sputum volume or thickened consistency lasting at least 48 hours, worsening shortness of breath (breathlessness), worsening exercise intolerance, increased fatigue or malaise, and the development of hemoptysis.[21]

People often report frequent bouts of "bronchitis" requiring therapy with repeated courses of antibiotics. People with bronchiectasis may have bad breath from active infection. On examination, crepitations and expiratory rhonchi may be heard with auscultation. Nail clubbing is a rare symptom.[3]

The complications of bronchiectasis include serious health conditions, such as respiratory failure and atelectasis: collapse or closure of a lung. Respiratory failure occurs when not enough oxygen passes from the lungs into the blood.[22] Atelectasis occur when one or more segments of the lungs collapse or do not inflate properly. Other pulmonary complications include lung abscess and empyema. Cardiovascular complications include cor pulmonale, in which there is enlargement and failure of the right side of the heart as a result of disease of the lungs.[23]

Causes

[edit]
Category Causes
Autoimmune disease Rheumatoid arthritis

Sjögren's disease

Impaired host defenses Cystic fibrosis

Primary ciliary dyskinesia

Primary immunodeficiency

HIV/AIDS

Job's syndrome

Post-infective Bacterial pneumonia

Mycobacterium infection

Viral infection

Congenital Tracheobronchomegaly

Marfan syndrome

Williams–Campbell syndrome

Young's syndrome

Alpha-1 antitrypsin deficiency

Hypersensitivity Allergic bronchopulmonary aspergillosis
Inflammatory bowel disease Ulcerative colitis

Crohn's disease

Malignancy Chronic lymphocytic leukemia

Graft-versus-host disease

Obstruction Tumor

Foreign body aspiration

Lymphadenopathy

Other Pneumonia

Chronic aspiration

Ammonia inhalation

Smoke inhalation

Radiation-induced lung disease

Yellow nail syndrome

There are many causes that can induce or contribute to the development of bronchiectasis. The frequency of these different causes varies with geographic location.[24] Cystic fibrosis (CF) is identified as a cause in up to half of cases.[3] Bronchiectasis without CF is known as non-CF bronchiectasis. Historically, about half of all cases of non-CF bronchiectasis were found to be idiopathic, or without a known cause.[25] However, more recent studies with a more thorough diagnostic work-up have found an etiology in 60–90% of patients.[24][26][27]

Cystic fibrosis

[edit]

Cystic fibrosis is the most common life-threatening autosomal recessive disease in the United States and Europe.[28] It is a genetic disorder that affects the lungs, but also the pancreas, liver, kidneys, and intestine.[29] It is caused by mutations in the CFTR protein, a chloride channel expressed in epithelial cells.[28] Lung disease results from clogging of the airways due to mucus build-up, decreased mucociliary clearance, and resulting inflammation.[30] In later stages, changes to the structure of the lung, such as bronchiectasis, occur.

Airway obstruction

[edit]

An airway obstruction can be caused by either an intraluminal mass such as a tumor or a foreign body.[31] The presence of an airway obstruction leads to a cycle of inflammation.[3] It is important to identify the presence of an obstruction because surgical resection is often curative if obstruction is the cause.[32] In adults, foreign body aspiration is often associated with an altered state of consciousness. The foreign body is often unchewed food, or part of a tooth or crown.[33] Bronchiectasis that results from foreign body aspiration generally occurs in the right lung in the lower lobe or posterior segments of the upper lobe.[34]

Lung infections

[edit]

A range of bacterial, mycobacterial, and viral lung infections are associated with the development of bronchiectasis. Bacterial infections commonly associated with bronchiectasis include P. aeruginosa, H. influenzae, and S. pneumoniae.[3] Gram-negative bacteria are more commonly implicated than gram-positive bacteria.[3] A history of mycobacterial infections such as tuberculosis can lead to damage of the airways that predisposes to bacterial colonization.[35] Severe viral infections in childhood can also lead to bronchiectasis through a similar mechanism.[36] Nontuberculous mycobacteria infections such as Mycobacterium avium complex are found to be a cause in some patients.[37] Recent studies have also shown Nocardia infections to been implicated in bronchiectasis.[38]

Impaired host defenses

[edit]

Impairments in host defenses that lead to bronchiectasis may be congenital, such as with primary ciliary dyskinesia, or acquired, such as with the prolonged use of immunosuppressive drugs.[39] Additionally, these impairments may be localized to the lungs or systemic throughout the body. In these states of immunodeficiency, there is a weakened or absent immune system response to severe infections that repeatedly affect the lung and eventually result in bronchial wall injury.[40] HIV/AIDS is an example of an acquired immunodeficiency that can lead to the development of bronchiectasis.[41]

Aspergillosis

[edit]

Allergic bronchopulmonary aspergillosis (ABPA) is an inflammatory disease caused by hypersensitivity to the fungus Aspergillus fumigatus.[42] It is suspected in patients with a long history of asthma and symptoms of bronchiectasis such as a productive, mucopurulent cough.[43] Imaging often shows peripheral and central airway bronchiectasis, which is unusual in patients with bronchiectasis caused by other disorders.[44]

Autoimmune diseases

[edit]

Several autoimmune diseases have been associated with bronchiectasis. Specifically, individuals with rheumatoid arthritis and Sjögren syndrome have increased rates of bronchiectasis.[45][46] In these diseases, the symptoms of bronchiectasis usually presents later in the disease course.[47] Other autoimmune diseases such as ulcerative colitis and Crohn's disease also have an association with bronchiectasis.[48] Additionally, graft-versus-host disease in patients who have undergone stem cell transplantation can lead to bronchiectasis as well.[39]

Lung injury

[edit]

Bronchiectasis could be caused by: inhalation of ammonia and other toxic gases,[49] chronic pulmonary aspiration of stomach acid from esophageal reflux,[50] or a hiatal hernia.[50]

Congenital

[edit]

Bronchiectasis may result from congenital disorders that affect cilia motility or ion transport.[51] A common genetic cause is cystic fibrosis, which affects chloride ion transport.[28] Another genetic cause is primary ciliary dyskinesia, a rare disorder that leads to immotility of cilia and can lead to situs inversus.[52] When situs inversus is accompanied by chronic sinusitis and bronchiectasis, this is known as Kartagener's syndrome.[53] Other rare genetic causes include Young's syndrome[54] and Williams–Campbell syndrome.[55] Tracheobronchomegaly, or Mournier-Kuhn syndrome is a rare condition characterized by significant tracheobronchial dilation and recurrent lower respiratory tract infections.[56] Individuals with alpha 1-antitrypsin deficiency have been found to be particularly susceptible to bronchiectasis, due to the loss of inhibition to enzyme elastase which cleaves elastin.[57] This decreases the ability of the alveoli to return to normal shape during expiration.[58]

Cigarette smoking

[edit]

A causal role for tobacco smoke in bronchiectasis has not been demonstrated.[39] Nonetheless, tobacco smoking can worsen pulmonary function and accelerate the progression of disease that is already present.[59][60]

Pathophysiology

[edit]
"Vicious cycle" theory of the pathogenesis of bronchiectasis

The development of bronchiectasis requires two factors: an initial injury to the lung (such as from infection, auto-immune destruction of lung tissue, or other destruction of lung tissue (as seen in gastroesophageal reflux disease or aspiration syndromes)) which leads to impaired mucociliary clearance, obstruction, or a defect in host defense.[21][3] This triggers a host immune response from neutrophils (elastases), reactive oxygen species, and inflammatory cytokines that results in progressive destruction of normal lung architecture. In particular, the elastic fibers of bronchi are affected.[13] The result is permanent abnormal dilation and destruction of the major bronchi and bronchiole walls.[61]

Disordered neutrophil function is believed to play a role in the pathogenesis of bronchiectasis. Neutrophil extracellular traps (NETs), which are extracellular fibers secreted by neutrophils that are used to trap and destroy pathogens, are hyperactive in bronchiectasis. Increased NET activity is associated with more severe bronchiectasis.[21] Neutrophil elastase, which is an extracellular protein secreted by neutrophils to destroy pathogens as well as host tissue, is also hyperactive in many cases of bronchiectasis.[21] An increased neutrophil elastase activity is also associated with worse outcomes and more severe disease in bronchiectasis.[21] The initial lung injury in bronchiectasis leads to an impaired mucociliary clearance of the lung airways, which leads to mucous stasis.[21] This mucous stasis leads to bacterial colonization in bronchiectasis, which leads to neutrophil activation.[21] This neutrophil activation leads to further tissue destruction and airway distortion by neutrophils in addition to direct tissue destruction by the pathogenic bacteria.[21] The distorted, damaged lung airways thus have impaired mucociliary clearance, leading to mucous stasis and bacterial colonization, leading to further neutrophil activation and thus fueling a self-perpetuating "vicious cycle" of inflammation in bronchiectasis.[21] This "vicious cycle" theory is the generally accepted explanation for the pathogenesis of bronchiectasis.[39]

Endobronchial tuberculosis commonly leads to bronchiectasis, either from bronchial stenosis or secondary traction from fibrosis.[34] Traction bronchiectasis characteristically affects peripheral bronchi (which lack cartilage support) in areas of end-stage fibrosis.[62]

Diagnosis

[edit]
CT scan of the lungs showing findings diagnostic of bronchiectasis. White and black arrows point to dilated bronchi characteristic of the disease.

The goals of a diagnostic evaluation for bronchiectasis are radiographic confirmation of the diagnosis, identification of potential treatable causes, and functional assessment of the patient. A comprehensive evaluation consists of radiographic imaging, laboratory testing, and lung function testing.[63]

Laboratory tests that are commonly part of the initial evaluation include a complete blood count, sputum cultures for bacteria, mycobacteria, and fungi, testing for cystic fibrosis, and immunoglobulin levels.[64] Additional tests that are sometimes indicated include testing for specific genetic disorders.[61]

Lung function testing is used for the assessment and monitoring of functional impairment due to bronchiectasis. These tests may include spirometry and walking tests.[39] Obstructive lung impairment is the most common finding but restrictive lung impairment can be seen in advanced disease. Flexible bronchoscopy may be performed when sputum studies are negative and a focal obstructing lesion is suspected.[31]

A chest X-ray is abnormal in most patients with bronchiectasis. Computed tomography is recommended to confirm the diagnosis and is also used to describe the distribution and grade the severity of the disease. Radiographic findings include airway dilation, bronchial wall thickening, and atelectasis.[65] Three types of bronchiectasis can be seen on CT scan, namely cylindrical, varicose, and cystic bronchiectasis.[66]

  • Bronchiectasis primarily in the middle lobe of the right lung
    Bronchiectasis primarily in the middle lobe of the right lung
  • Bronchiectasis secondary to a large carcinoid tumor (not shown) that was completely obstructing the bronchus proximally. Dilation of the airways is present.
    Bronchiectasis secondary to a large carcinoid tumor (not shown) that was completely obstructing the bronchus proximally. Dilation of the airways is present.

Prevention

[edit]

In preventing bronchiectasis, it is necessary to prevent the lung infections and lung damage that can cause it.[22] Children should be immunized against measles, pertussis, pneumonia, and other acute respiratory infections of childhood. Additionally, parents should stay alert to keep children from inhaling objects such as pieces of food or small toys that may get stuck in the small airways.[22] Smoking and other toxic fumes and gases should be avoided by all patients with bronchiectasis to decrease the development of infections (such as bronchitis) and further complications.[67]

Treatments to slow down the progression of this chronic disease include keeping bronchial airways clear and secretions weakened through various forms of airway clearance. Aggressively treating bronchial infections with antibiotics to prevent the destructive cycle of infection, damage to bronchi and bronchioles, and further infection is also standard treatment. Regular vaccination against pneumonia, influenza, and pertussis are generally advised. A healthy body mass index and regular doctor visits may have beneficial effects on the prevention of progressing bronchiectasis. The presence of hypoxemia, hypercapnia, dyspnea level and radiographic extent can greatly affect the mortality rate from this disease.[68]

Management

[edit]

A comprehensive approach to the management of bronchiectasis is recommended.[69] It is important to establish whether an underlying modifiable cause, such as immunoglobulin deficiency or alpha-1 antitrypsin deficiency is present.[69] The next steps include controlling infections and bronchial secretions, relieving airway obstructions, removing affected portions of lung by surgery, and preventing complications.[70]

Airway clearance

[edit]

The goal of airway clearance therapy is to loosen secretions and interrupt the cycle of inflammation and infection.[71] Airway clearance techniques improve difficulty breathing, cough, and help patients cough up phlegm and mucus plugs.[72] Airway clearance usually uses an inhaled agent (hypertonic saline) with chest physiotherapy, such as high-frequency chest wall oscillation.[3] Many airway clearance techniques and devices exist. The choice of a technique or device is based on the frequency and tenacity of phlegm, patient comfort, cost, and the patient's ability to use the technique or device with minimal interference to their lifestyle.[73] The active cycle of breathing technique (ACBT), which can be employed with or without a flutter device, is beneficial in treating those with bronchiectasis.[74] Mucolytic agents such as dornase alfa are not recommended for individuals with non-CF bronchiectasis.[3] Mannitol is a hyperosmolar agent that is thought to hydrate airway secretions; however, clinical trials with it have not demonstrated efficacy.[73]

Anti-inflammatories

[edit]

The two most commonly used classes of anti-inflammatory therapies are macrolides and corticosteroids.[3]

Despite also being antibiotics, macrolides exert immunomodulatory effects on the host inflammatory response without systemic suppression of the immune system.[3] These effects include modifying mucus production, inhibition of biofilm production, and suppression of inflammatory mediators.[39] Three large multicenter, randomized trials have shown reduced rates of exacerbations and improved cough and dyspnea with use of macrolide therapy.[64] The impact of adverse effects of macrolides such as gastrointestinal symptoms, hepatotoxicity, and increased antimicrobial resistance needs ongoing review and study.[17]

Inhaled corticosteroid therapy can reduce sputum production and decrease airway constriction over a period of time, helping prevent progression of bronchiectasis.[19] Long-term use of high-dose inhaled corticosteroids can lead to adverse consequences such as cataracts and osteoporosis.[3] It is not recommended for routine use in children.[75] One commonly used therapy is beclometasone dipropionate.[76]

Antibiotics

[edit]
Azithromycin is a macrolide commonly used in bronchiectasis.

Antibiotics are used in bronchiectasis to eradicate P. aeruginosa or MRSA, to suppress the burden of chronic bacterial colonization, and to treat exacerbations.[3] The use of daily oral non-macrolide antibiotic treatment has been studied in small case series, but not in randomized trials.[64] The role of inhaled antibiotics in non-CF bronchiectasis has recently evolved with two society guidelines and a systematic review suggesting a therapeutic trial of inhaled antibiotics in patients with three or more exacerbations per year and P. aeruginosa in their sputum.[77][78] Options for inhaled antibiotics include aerosolized tobramycin, inhaled ciprofloxacin, aerosolized aztreonam, and aerosolized colistin.[39] However, there arises a problem with inhaled antibiotic treatments, such as ciprofloxacin, of staying in the desired area of the infected lung tissues for sufficient time to provide optimal treatment.[79] To combat this and prolong the amount of time the antibiotic spends in the lung tissue, current study trials have moved to develop inhalable nanostructured lipid carriers for the antibiotics.[79]

Bronchodilators

[edit]

Some clinical trials have shown a benefit with inhaled bronchodilators in certain people with bronchiectasis.[3] In people with demonstrated bronchodilator reversibility on spirometry, the use of inhaled bronchodilators resulted in improved dyspnea, cough, and quality of life without any increase in adverse events.[63] However, overall, there is a lack of data to recommend the use of bronchodilators in all patients with bronchiectasis.[80]

Surgery

[edit]

The primary role of surgery in the management of bronchiectasis is in localized disease to remove segments of the lung or to control massive hemoptysis.[39] Additionally, surgery is used to remove an airway obstruction that is contributing to bronchiectasis. The goals are conservative, aiming to control specific disease manifestations rather than cure or eliminate all areas of bronchiectasis.[81] Surgical case series have shown low operative mortality rate (less than 2%) and improvement of symptoms in the majority of patients selected to receive surgery.[82] However, no randomized clinical trials have been performed evaluating the efficacy of surgery in bronchiectasis.[81]

Clinical trials

[edit]

Results from a phase 2 clinical trial were published in 2018.[83] In a placebo-controlled, double-blind study conducted in 256 patients worldwide, patients who received brensocatib reported prolonged time to the first exacerbation and also reduced rate of yearly exacerbation.[83] Brensocatib (Brinsupri) was approved for medical use in the United States in August 2025.[84]

Prognosis

[edit]

Two clinical scales have been used to predict disease severity and outcomes in bronchiectasis: the Bronchiectasis Severity Index and the FACED scale. The FACED scale uses the FEV-1 (forced expiratory volume in 1 second), age of the affected person, presence of chronic infection, extent of disease (number of lung lobes involved) and dyspnea scale rating (MRC dyspnea scale) to predict clinical outcomes in bronchiectasis. The Bronchiectasis Severity Index uses the same criteria as the FACED scale, in addition to including criteria related to the number of hospital admissions, annual exacerbations, colonization with other organisms, and BMI (body mass index) less than 18.5. A decreased FEV-1, increasing age, presence of chronic infection (especially pseudomonas), a greater extent of lung involvement, high clinical dyspnea scale ratings, increased hospital admissions, a high number of annual exacerbations, and a BMI less than 18.5 lead to higher scores on both clinical scales and are associated with a poor prognosis in bronchiectasis; including increased mortality.[21]

Epidemiology

[edit]

The prevalence and incidence of bronchiectasis are unclear, as the symptoms are variable.[85] The disease affects between 1 per 1000 and 1 per 250,000 adults.[10] The disease is more common in women and in the elderly.[3] In a Medicare cohort study in the United States, consisting of adults 65 years and older, the prevalence of bronchiectasis was 701 per 100,000 persons.[86] A similar prevalence rate of bronchiectasis has been reported in other countries including China, Germany, the United Kingdom, Spain and Singapore.[21] Those with a dual COPD and bronchiectasis diagnosis are more likely to be cigarette smokers and more likely to be hospitalized as compared to those with bronchiectasis without COPD.[86] It became less common since the 1950s, with the introduction of antibiotics.[10] It is more common among certain ethnic groups such as indigenous people.[10]

An estimated 350,000 to 500,000 adults have bronchiectasis in the United States.[87] Specifically, children of the indigenous populations of Australia, Alaska, Canada and New Zealand have significantly higher rates than other populations.[88] Overall, a shortage of data exists concerning the epidemiology of bronchiectasis in Asia, Africa, and South America.[88]

The prevalence and incidence of bronchiectasis have increased greatly in the 21st century. In a Medicare cohort analysis, consisting of adults 65 years and older in the United States, the annual rates of diagnosis have increased by 8.7% every year between 2000 and 2007.[3][89] This large increase in the diagnosis of bronchiectasis may be due to increased recognition of the disease (including more widespread use of CT scans) or it may be due to an increase in the underlying causes of bronchiectasis.[21]

History

[edit]

René Laennec, the man who invented the stethoscope, used his invention to first discover bronchiectasis in 1819.[90]

The disease was researched in greater detail by Sir William Osler, one of the four founding professors of Johns Hopkins Hospital, in the late 1800s. It is suspected that Osler himself died of complications from undiagnosed bronchiectasis. His biographies mention that he had frequent, severe chest infections for many years.[91]

The term "bronchiectasis" comes from the Greek words bronkhia (meaning "airway") and ektasis (meaning "widening").[92]

Society and culture

[edit]

Judith Durham of the Australian band The Seekers died of bronchiectasis on 5 August 2022, at the age of 79.[93]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Bronchiectasis

View on Grokipedia
from Grokipedia
Bronchiectasis is a chronic respiratory condition characterized by irreversible widening and damage to the bronchi, the airways that carry air to and from the lungs, resulting in impaired , mucus accumulation, and recurrent infections. This structural abnormality leads to a cycle of and further bronchial destruction, distinguishing it from reversible airway diseases like . The condition often develops following severe or repeated lung infections, such as those caused by bacteria, viruses, or fungi, or due to underlying disorders including , , , or aspiration. Post-infectious bronchiectasis is a common form, particularly in regions with high tuberculosis prevalence, while non-cystic fibrosis bronchiectasis accounts for the majority of cases in adults. Risk factors include childhood respiratory infections, environmental exposures like or , and autoimmune diseases such as . Symptoms typically include a persistent productive with copious (often yellow or green), , dyspnea, fatigue, and recurrent exacerbations marked by increased and fever. In advanced stages, patients may experience , wheezing, or digital clubbing, and complications such as , lung abscesses, or can arise. Diagnosis relies on clinical history, chest —particularly high-resolution computed tomography (HRCT) revealing bronchial dilation, lack of tapering, or cystic changes—and exclusion of other conditions via pulmonary function tests or . Management aims to control symptoms, prevent exacerbations, and improve , as there is no cure for the structural damage. Core treatments include airway clearance therapies (e.g., , ), long-term antibiotics for infection control, mucolytics to thin secretions, and vaccinations against and pneumococcus. For those with underlying causes, targeted therapies like immunoglobulin replacement for immunodeficiencies or CFTR modulators for are employed; bronchodilators, inhaled corticosteroids, or surgical resection may be used in select cases. Recent guidelines emphasize multidisciplinary care, including , to address the growing global burden, with prevalence estimated at approximately 680 per 100,000 adults as of 2024.

Overview

Definition and Classification

Bronchiectasis is a chronic respiratory condition characterized by the irreversible dilatation of the bronchi, resulting from the destruction of the elastic and muscular components of the bronchial walls, which impairs and predisposes to recurrent infections. This structural damage distinguishes it from reversible airway narrowing seen in other conditions and leads to a vicious cycle of and further bronchial remodeling. The condition can occur as a primary or secondary to underlying disorders, such as , though detailed etiologies are addressed elsewhere. Classifications of bronchiectasis primarily focus on morphological patterns and extent of involvement, aiding in clinical assessment and prognosis. Morphologically, the condition is categorized into three main types based on Reid's seminal pathological classification: cylindrical (or tubular), featuring uniform, smooth dilatation resembling a tramline; varicose, with irregular, beaded contours due to focal constrictions; and cystic (or saccular), involving severe balloon-like expansions often filled with , representing the most advanced form. These patterns, originally described via bronchography, are now evaluated using (HRCT). Regarding extent, bronchiectasis is classified as focal if confined to one lobe or segment, typically post-infectious or localized, or diffuse if involving multiple lobes bilaterally, often indicating systemic or genetic underpinnings. Historically, classification systems have evolved from descriptive to multidimensional severity scoring for better prognostic utility. Reid's work in the mid-20th century laid the foundation for morphological typing, correlating gross with bronchographic findings. In the 1990s, the Reiff score introduced a radiological severity metric, assigning points (1-3 per lobe) based on dilatation degree across up to six lobes (maximum score 18), with higher scores indicating greater extent and severity. More recent advancements, endorsed by the European Respiratory Society (ERS), include comprehensive tools like the FACED score (2014) and Bronchiectasis Severity Index (BSI, 2014), which integrate clinical, radiological, and microbiological factors to stratify mortality risk beyond mere morphology. These systems have shifted focus from isolated anatomical features to holistic assessment. Bronchiectasis must be differentiated from chronic bronchitis, a component of defined by productive cough for at least three months in two consecutive years without permanent bronchial dilatation or structural destruction. While both involve chronic airway inflammation, chronic bronchitis lacks the irreversible dilation central to bronchiectasis, often resolving with or management of reversible factors.

Clinical Importance

Bronchiectasis represents a significant burden, with a pooled estimated at 680 per 100,000 adults based on a 2024 of 15 studies encompassing over 437 million individuals. This condition imposes substantial morbidity through recurrent exacerbations, reduced , and increased risk of , particularly in aging populations where rises sharply with age. The incidence has been increasing worldwide, driven by improved diagnostic capabilities such as (HRCT) and demographic shifts toward older age groups, as evidenced by a Chinese cohort study showing a significant rise in urban adult cases from 2013 to 2017. The economic impact of bronchiectasis is profound, primarily due to frequent hospitalizations for acute exacerbations and chronic needs. A 2023 systematic review of healthcare costs reported annual per-patient expenditures ranging from $3,579 to $82,545 USD in adults, with hospitalizations accounting for the majority of expenses across multiple studies. These costs highlight the strain on healthcare systems, especially in regions with limited access to specialized care. Non-cystic fibrosis bronchiectasis (NCFB) constitutes the majority of cases in adults, often underrecognized and misdiagnosed as (COPD), leading to delayed appropriate management. Comprehensive reviews indicate that NCFB accounts for the bulk of bronchiectasis diagnoses beyond childhood, with symptoms like and production frequently attributed to COPD in settings. This diagnostic overlap exacerbates the disease burden by postponing interventions that could mitigate progression. Emerging trends since 2020 have further amplified the clinical relevance of bronchiectasis, with post-COVID-19 sequelae contributing to new or worsened cases through mechanisms like persistent inflammation and traction bronchiectasis observed on HRCT imaging. Enhanced HRCT utilization during and after the pandemic has also facilitated earlier detection, underscoring ongoing gaps in awareness and the need for targeted research to address underdiagnosis in non-CF populations. In 2025, the U.S. FDA approved brensocatib (BRINSUPRI), the first targeted therapy for non-cystic fibrosis bronchiectasis, reducing pulmonary exacerbations, alongside updated ERS and CHEST guidelines incorporating these advances.

Signs and Symptoms

Respiratory Symptoms

The primary respiratory symptom of bronchiectasis is a chronic productive , affecting up to 98% of patients and often present for years. This typically involves daily production exceeding 30 mL, which is frequently purulent and results from bacterial in the dilated bronchi. The purulence arises from ongoing and impaired , leading to persistent mucus retention in the airways. Hemoptysis, or coughing up blood, occurs in 56% to 92% of individuals with bronchiectasis and can range from mild streaking of sputum to massive, life-threatening bleeding. It stems from erosion of the bronchial vasculature due to chronic infection and inflammation. While most episodes are minor, severe cases may require urgent intervention. Dyspnea, reported in approximately 62% of patients, and wheezing, in about 22%, are common exertional symptoms caused by airflow obstruction from accumulated secretions and bronchial narrowing. These manifestations worsen progressively in advanced disease, sometimes accompanied by digital clubbing, a sign of chronic hypoxemia though uncommon in bronchiectasis. Wheezing often presents intermittently, mimicking asthmatic patterns due to reversible airway components. Exacerbations represent acute worsenings of respiratory symptoms, characterized by increased volume and purulence, alongside heightened , dyspnea, and wheezing, often triggered by bacterial infections. These episodes, which occur in a majority of patients annually, reflect intensified retention and responses in the damaged airways.

Systemic Manifestations

Bronchiectasis, as a chronic condition, often leads to systemic effects beyond the , primarily through sustained and . is a prominent manifestation, resulting from the increased energy demands of labored and the catabolic effects of ongoing , which elevate resting energy expenditure. frequently accompanies this, driven by heightened metabolic needs and reduced caloric intake due to anorexia associated with chronic illness. These symptoms contribute to overall debility and diminished in affected individuals. Digital changes such as finger clubbing and arise from chronic hypoxia and vascular alterations in severe cases. Clubbing, characterized by bulbous enlargement of the fingertips, occurs in approximately 2-3% of patients overall but can be observed in up to 50% of pediatric cases or those with advanced disease severity. Cyanosis, a bluish discoloration of the skin and mucous membranes, reflects inadequate oxygenation and is more common in advanced bronchiectasis with significant ventilatory impairment. Secondary systemic complications further compound the burden of bronchiectasis. develops from persistent anorexia and secondary to chronic inflammation, exacerbating and frailty. is common, stemming from inflammatory cytokines that suppress and iron utilization. is prevalent, particularly in males with low and severe bronchial involvement, worsened by immobility from dyspnea and potential use of corticosteroids in management. The psychological toll of bronchiectasis is substantial, with anxiety and depression reported in 20% to 65% of patients across studies, attributable to the unrelenting burden of symptoms, frequent hospitalizations, and restrictions imposed by the chronic illness. These issues can perpetuate a cycle of reduced adherence to and worsened physical outcomes.

Causes and Risk Factors

Acquired Causes

Acquired causes of bronchiectasis encompass a range of environmental, infectious, and systemic factors that lead to bronchial damage in individuals without inherent genetic predispositions. These etiologies often involve recurrent or severe insults to the airways, resulting in irreversible dilatation and impaired . Post-infectious processes represent the predominant acquired mechanism, accounting for approximately 30-40% of cases globally, though varies by region and population. Other contributors include mechanical obstructions, immunodeficiencies, toxic exposures, and autoimmune conditions, each predisposing the lungs to chronic inflammation and . Post-infectious bronchiectasis is the most common acquired form, arising from severe or repeated respiratory infections that damage bronchial walls and promote persistent microbial colonization. In childhood, infections such as measles or pertussis can initiate this process, while in adults, bacterial pneumonia—particularly from pathogens like Pseudomonas aeruginosa or Haemophilus influenzae—or nontuberculous mycobacterial infections are frequent triggers. Studies indicate that post-infectious etiologies comprise 19-40% of bronchiectasis cases, with higher rates in regions where tuberculosis remains endemic, such as parts of Asia. These infections disrupt normal airway defenses, leading to a cycle of inflammation and structural remodeling that culminates in bronchiectasis. Airway obstruction contributes to acquired bronchiectasis by causing distal bronchial collapse, mucus stasis, and secondary infections. Common culprits include aspirated foreign bodies, endobronchial tumors, or extrinsic compression from enlarged nodes due to or granulomatous disease. This mechanical impediment impairs ventilation and clearance, fostering and recurrent in affected segments. While less prevalent than post-infectious causes, obstruction accounts for a notable subset of cases, particularly in pediatric or oncologic populations, and early removal of the obstructing lesion can mitigate progression. Acquired immunodeficiencies heighten susceptibility to recurrent pulmonary infections, thereby promoting bronchiectasis through chronic airway insult. Conditions such as or secondary —often linked to medications, malignancies, or protein-losing enteropathies—compromise and mucociliary function. For instance, in HIV patients, opportunistic infections exacerbate bronchial damage, with bronchiectasis prevalence rising as counts decline. Immunoglobulin replacement therapy in hypogammaglobulinemia cases has shown potential to reduce infection frequency and slow structural lung changes. Secondary immunodeficiencies underlie about 5-12% of bronchiectasis etiologies in adults. Toxic exposures represent another key acquired pathway, where irritants directly injure bronchial or indirectly worsen infection susceptibility. Chronic aspiration, often associated with (GERD) or , introduces gastric contents into the airways, causing and subsequent . Inhalational injuries from smoke, , or other chemicals can induce acute and long-term dilatation, as seen in cases of hydrocarbon aspiration or industrial accidents. Cigarette smoking acts as a disease modifier, accelerating severity by impairing ciliary function and increasing , with smokers exhibiting higher exacerbation rates and worse lung function in bronchiectasis cohorts. Autoimmune diseases, particularly (RA), are significant acquired contributors, with pulmonary involvement manifesting as or immune-mediated bronchial destruction. Up to 20% of RA patients develop bronchiectasis, often independently of rheumatoid nodules or , due to systemic inflammation targeting airway walls. Prevalence estimates from high-resolution CT studies range from 15-29%, with risk factors including longer disease duration and seropositivity for . Other autoimmune conditions, such as Sjögren's syndrome, may similarly predispose through lymphocytic infiltration, though RA remains the most strongly associated. Disease-modifying antirheumatic drugs can influence outcomes, but screening for bronchiectasis is recommended in at-risk RA populations.

Genetic and Congenital Causes

Bronchiectasis can arise from genetic mutations that impair airway clearance or structural integrity, with representing the most prominent monogenic cause. Caused by biallelic mutations in the CFTR gene on , leads to defective chloride transport, resulting in viscous accumulation in the airways that predisposes to recurrent infections and progressive bronchial dilation. Genotype-phenotype correlations are well-established; for instance, patients with at least one ΔF508 mutation often exhibit severe pulmonary involvement, including early-onset bronchiectasis, while milder alleles like R117H may present with later, less aggressive disease. In cohorts of bronchiectasis patients, accounts for approximately 3-10% of cases in adults, though this proportion rises to 10-15% in pediatric populations where screening is routine. Augmentation therapies targeting CFTR function, such as for specific mutations, can mitigate mucus-related damage and slow bronchiectasis progression. Primary ciliary dyskinesia (PCD), another key genetic etiology, stems from autosomal recessive mutations disrupting motile cilia structure and function, thereby abolishing effective mucociliary clearance and fostering chronic airway inflammation and bronchiectasis. Common defects involve dynein arms, as seen in mutations of DNAH5 (encoding an outer dynein arm heavy chain) or DNAI1, which together account for 15-30% of PCD cases; more recent identifications include CCDC39 and CCDC40 variants affecting inner dynein arms, discovered around 2010 but with expanded clinical correlations post-2015 through next-generation sequencing. Approximately 50% of PCD patients develop situs inversus, defining Kartagener syndrome, a subtype where bronchiectasis often manifests in the upper lobes due to impaired embryonic nodal cilia. PCD underlies 1-5% of non-cystic fibrosis bronchiectasis in adults, with whole-genome sequencing revealing underdiagnosis in up to 20% of unexplained cases through detection of biallelic variants in over 40 ciliopathy genes. Additional genetic conditions contribute less frequently but distinctly to bronchiectasis pathogenesis. Alpha-1 antitrypsin deficiency (AATD), resulting from SERPINA1 gene mutations (notably PiZ and PiS alleles), diminishes protease inhibition in the , promoting unchecked activity that erodes bronchial walls and induces dilatation, observed in 25-30% of severe AATD patients. In bronchiectasis cohorts, AATD prevalence ranges from 1-2%, with augmentation therapy using purified potentially stabilizing function in affected individuals. , caused by FBN1 mutations disrupting , rarely associates with bronchiectasis (prevalence <5% in Marfan cohorts), likely via weakened bronchial cartilage or chest wall deformities impairing ventilation. Congenital malformations represent developmental origins of bronchiectasis, independent of ciliary or mucus defects. Mounier-Kuhn syndrome, or congenital tracheobronchomegaly, features atrophy of elastic and smooth muscle in the trachea and proximal bronchi due to unknown genetic factors, leading to flaccid airways prone to collapse and secondary infections with bronchiectasis in 70-90% of cases. Williams-Campbell syndrome involves deficient cartilage in fourth- to sixth-order bronchi, a rare autosomal recessive or sporadic condition causing expiratory collapse and cystic bronchiectasis predominantly in the mid-lung zones.

Pathophysiology

Mechanisms of Bronchial Damage

Bronchiectasis is characterized by a self-perpetuating "vicious cycle" of airway damage, first proposed by Cole in 1986, wherein initial insults such as infection or inflammation impair mucociliary clearance, leading to recurrent bacterial colonization and persistent neutrophilic inflammation that further exacerbates bronchial dilation and tissue destruction. This model has been updated in recent years to a "vicious vortex" framework that emphasizes four interconnected drivers: chronic infection, inflammation, impaired mucociliary clearance, and structural lung damage. This cycle involves the release of neutrophil elastase (NE), a serine protease from activated neutrophils, which degrades elastin in the airway wall, compromising structural integrity and promoting irreversible dilatation. Elevated sputum NE levels in stable bronchiectasis patients correlate with disease severity, underscoring its role in perpetuating the inflammatory loop. Airway wall remodeling in bronchiectasis manifests as profound structural alterations, including loss of ciliated epithelium, squamous metaplasia, and hypertrophy of airway smooth muscle, which collectively impair normal airway function and contribute to dilation. The reduction in ciliated cells disrupts mucociliary transport, while squamous metaplasia replaces functional epithelium with stratified squamous cells, further hindering clearance and fostering a pro-inflammatory environment. Smooth muscle hypertrophy thickens the airway wall, potentially exacerbating obstruction and remodeling through mechanical stress and cytokine-mediated pathways. Mucus hypersecretion arises from goblet cell hyperplasia and a diminished periciliary layer, leading to viscous mucus accumulation that stagnates in dilated bronchi and amplifies infection risk. This process is driven by elevated proinflammatory cytokines such as interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α), which promote goblet cell differentiation and mucus production while recruiting additional neutrophils. Sputum levels of IL-8 and TNF-α are markedly increased in bronchiectasis, correlating with neutrophil influx and hypersecretion severity. Vascular changes in bronchiectasis include hypertrophy of bronchial arteries, a compensatory response to chronic hypoxia and inflammation that increases blood flow to damaged areas but heightens the risk of hemoptysis. Dilated bronchial arteries, often exceeding 2 mm in diameter, become fragile and prone to rupture, particularly in severe disease, making them a primary source of life-threatening bleeding. This neovascularization is linked to ongoing tissue repair but contributes to the overall pathology by promoting edema and further airway instability.

Inflammatory and Infectious Processes

Chronic infection plays a central role in the progression of bronchiectasis, with Pseudomonas aeruginosa being a predominant pathogen responsible for 20-40% of bacterial infections. This bacterium forms biofilms within the dilated airways, which are facilitated by bronchial structural damage, enhancing its persistence and resistance to host defenses and antibiotics. Biofilm formation involves quorum sensing mechanisms, where P. aeruginosa coordinates gene expression through signaling molecules like acyl-homoserine lactones, promoting the production of extracellular polymeric substances that shield bacterial communities. The host immune response in bronchiectasis is characterized by dysregulated inflammation, including exaggerated Th2-mediated pathways that contribute to eosinophilic infiltration alongside dominant neutrophilic responses. Alveolar macrophages exhibit impaired phagocytosis, particularly against common respiratory pathogens like nontypeable Haemophilus influenzae, leading to reduced clearance of apoptotic cells and bacteria, which perpetuates inflammation and microbial colonization. Emerging research as of 2025 explores targeted therapies for neutrophil dysfunction, such as dipeptidyl peptidase 1 (DPP-1) inhibitors, to interrupt these inflammatory pathways. Biomarkers of disease activity include elevated sputum neutrophil counts, often exceeding thresholds indicative of active inflammation, and high levels of free DNA derived from neutrophil extracellular traps, both correlating with exacerbation risk and lung function decline. These markers reflect the intensity of ongoing neutrophilic inflammation and can guide monitoring of inflammatory burden. Recent post-2022 research highlights microbiome dysbiosis in bronchiectasis, characterized by reduced microbial diversity and dominance of pathogens like P. aeruginosa, which is strongly linked to increased exacerbation frequency and poorer clinical outcomes. This dysbiosis disrupts ecological balance in the airways, fostering chronic infection cycles that amplify inflammatory processes.

Diagnosis

Clinical Evaluation

The clinical evaluation of suspected bronchiectasis begins with a detailed history to identify characteristic features and potential etiologies. Patients typically report a chronic cough lasting months to years, often productive of daily sputum that may be mucopurulent or purulent, with volumes exceeding 30 mL per day in moderate to severe cases. Inquiry should focus on the frequency and severity of exacerbations, defined as worsening respiratory symptoms requiring antibiotics or hospitalization, as recurrent episodes (e.g., two or more per year) are common and inform disease severity. A family history of (CF) or (PCD) is crucial to screen for genetic causes, prompting targeted testing if present. Physical examination may reveal signs of chronic airway disease, though findings can be normal in mild cases. Auscultation frequently detects crackles, present in approximately 75% of patients and often bibasilar, reflecting mucus accumulation and bronchial dilation; wheezes occur in about 22% due to airflow limitation. Digital clubbing is observed in variable degrees, particularly in advanced disease or with hypoxemia, while rhonchi may indicate underlying airway obstruction from causes like foreign body aspiration or tumors. Additional findings, such as signs of systemic involvement (e.g., weight loss or fatigue), help assess overall impact. Risk stratification during evaluation employs validated scoring tools like the Bronchiectasis Severity Index (BSI), which integrates clinical variables including age (>70 years scoring higher risk), forced expiratory volume in 1 second (FEV1 <30% predicted indicating severe impairment), and history of exacerbations or hospitalizations to predict mortality, future exacerbations, and healthcare needs. The BSI categorizes patients into low (0-4 points), intermediate (5-8 points), or high (≥9 points) risk groups, guiding management intensity without requiring imaging. Differential diagnosis emphasizes distinguishing bronchiectasis from conditions like asthma or chronic obstructive pulmonary disease (COPD), where persistent daily sputum production and recurrent infections predominate, unlike the episodic symptoms and reversible airflow obstruction in asthma or fixed obstruction in COPD. Symptoms such as chronic cough and sputum production often prompt this evaluation.

Imaging and Laboratory Tests

High-resolution computed tomography (HRCT) of the chest serves as the gold standard for diagnosing bronchiectasis, providing detailed visualization of bronchial abnormalities that confirm the condition. Key radiographic signs include bronchial dilatation, where the internal diameter of the bronchus exceeds that of the adjacent pulmonary artery (bronchoarterial ratio >1), often manifesting as the classic signet ring sign on axial images; lack of normal bronchial tapering toward the periphery; and bronchial wall thickening, typically exceeding 1.5 mm in adults. These features are most evident in the lower lobes, particularly the left lower lobe, as the left lung is more commonly affected than the right, and allow differentiation from other airway diseases, with HRCT sensitivity approaching 95% for detecting bronchiectasis when performed with thin-section slices (1-2 mm). To assess disease severity and extent, the Bhalla scoring system is widely used, originally developed for but adapted for non-cystic fibrosis bronchiectasis; it evaluates multiple parameters including the degree of bronchiectasis, bronchial wall thickening, plugging, and associated changes like sacculation or generations of bronchial involvement, yielding a total score from 3 to 25, where lower scores indicate more severe structural damage. Laboratory tests support the diagnosis by identifying underlying etiologies and infectious contributors. and are essential to detect common pathogens such as and , guiding targeted antimicrobial therapy and revealing chronic colonization patterns in up to 70% of cases. For suspected as a cause, quantitative sweat testing remains the gold standard, with levels >60 mmol/L diagnostic in most contexts, often confirmed by genetic analysis of CFTR mutations. Serum immunoglobulin levels (IgG, IgA, IgM, and subclasses) are routinely measured to screen for immunodeficiencies, as underlies approximately 10-15% of non-cystic fibrosis bronchiectasis cases. Pulmonary function tests typically reveal an obstructive ventilatory defect, characterized by a reduced forced expiratory volume in 1 second to forced vital capacity ratio (FEV1/FVC <70%), reflecting airflow limitation due to bronchial distortion. Hyperinflation is common, evidenced by elevated residual volume (>120% predicted) and total lung capacity (>120% predicted), indicating air trapping from impaired mucociliary clearance. In cases of focal or localized bronchiectasis, flexible bronchoscopy may be employed for direct visualization, , or targeted cultures to exclude endobronchial obstructions like tumors or foreign bodies, particularly when HRCT suggests asymmetry without an evident infectious trigger. Recent advances in imaging incorporate (AI) enhancements to HRCT for earlier detection, such as automated quantification of bronchiectasis severity via airway-to-artery ratios and texture analysis, improving sensitivity for subclinical changes in at-risk populations like those with COPD.

Prevention

Primary Prevention Strategies

Primary prevention of bronchiectasis focuses on averting the initial onset by targeting modifiable risk factors, particularly in vulnerable populations such as children and individuals with potential predispositions to severe respiratory infections. plays a central role in this strategy, as post-infectious damage from pathogens like , virus, and is a leading acquired cause. Routine with pneumococcal conjugate vaccines (PCV15, PCV20, or PCV21), annual influenza vaccines, and the pertussis component of DTaP/Tdap has contributed to reducing the incidence of severe lower respiratory infections that can lead to bronchiectasis by reducing severe lower respiratory infections, potentially mitigating risks for its development. For instance, widespread PCV implementation has lowered invasive pneumococcal disease rates by up to 90% in vaccinated children, indirectly mitigating risks for chronic lung sequelae. Environmental controls are essential for minimizing exposure to irritants that exacerbate airway vulnerability, especially in children where indoor air pollution from fuels or heightens susceptibility. Public health programs promoting among adults and prohibiting tobacco exposure around children can significantly lower bronchiectasis risk, as active and impairs and is associated with a small increased risk (adjusted 1.06–1.12 for current smokers) of non-cystic fibrosis bronchiectasis. Similarly, interventions to reduce indoor pollutants—such as improved ventilation, use of clean cooking fuels, and —have been shown to decrease respiratory symptoms and frequency in at-risk households, with studies reporting up to 50% reductions in particulate matter exposure leading to fewer acute events. These measures are particularly impactful in low-resource settings where household air pollution affects approximately 2.6 billion people globally as of 2023. Early intervention for aspiration risks in infants, often linked to (GERD), is critical to prevent recurrent microaspiration that damages airways. Non-pharmacologic strategies like upright positioning after feeds, thickened formula, and smaller, more frequent meals can help reduce reflux episodes in affected infants, thereby lowering the incidence of and subsequent bronchiectasis development. In cases of suspected GERD, timely evaluation and management—guided by pediatric guidelines—help avert chronic lung injury, with conservative therapies often resolving symptoms in many infants without progression to respiratory complications. Public health efforts also include screening for underlying immunodeficiencies in children presenting with recurrent respiratory infections, enabling early immunoglobulin replacement or antimicrobial prophylaxis to halt progression to bronchiectasis. For example, newborn screening for (SCID) has increased early diagnosis rates, enabling early intervention to prevent complications such as bronchiectasis through timely intervention. Targeted testing for antibody deficiencies in those with two or more severe infections per year—such as measuring IgG, IgA, and IgM levels—facilitates proactive care, as untreated primary immunodeficiencies account for 10-20% of pediatric bronchiectasis cases.

Secondary Prevention Measures

Secondary prevention in bronchiectasis focuses on strategies to mitigate disease progression and reduce the frequency of exacerbations in individuals already diagnosed with the condition. A key component is prophylaxis through long-term therapy, particularly for patients experiencing frequent exacerbations (defined as three or more per year). , administered at a dose of 250 mg three times per week, has been shown to significantly decrease the rate of pulmonary exacerbations by approximately 44% compared to , based on moderate-certainty from randomized controlled trials. This regimen is recommended by major guidelines for non-cystic fibrosis bronchiectasis patients without , with treatment typically continued for at least 6 to 12 months and reassessed based on response. Long-term use requires monitoring for side effects such as gastrointestinal upset, hearing changes, and , with dose adjustments (e.g., to 500 mg three times weekly) considered if tolerated. Education on airway hygiene is essential for long-term control, emphasizing techniques that promote mucus clearance and minimize bronchial stasis to prevent recurrent infections. Daily postural drainage, involving specific body positions to use gravity-assisted clearance combined with percussion or vibration, is a cornerstone intervention taught to patients and caregivers. Guidelines strongly endorse regular airway clearance techniques for all bronchiectasis patients, as they improve sputum expectoration, reduce infection risk, and enhance quality of life without significant adverse effects. Patient adherence is supported through structured training programs, often integrated with devices like oscillating positive expiratory pressure masks for added efficacy during stable periods. Managing associated comorbidities plays a critical role in secondary prevention by addressing factors that exacerbate bronchial inflammation or promote aspiration. Treatment of chronic rhinosinusitis, which affects up to 60% of bronchiectasis patients and facilitates of pathogens, involves , topical corticosteroids, and antibiotics as needed to reduce lower airway colonization. Similarly, optimizing (GERD) management with proton pump inhibitors and lifestyle modifications (e.g., elevated head of ) minimizes acid aspiration, a known trigger for exacerbations in susceptible individuals. Routine screening and multidisciplinary care for these conditions are advised to interrupt vicious cycles of inflammation and infection. Ongoing monitoring is vital to detect early progression and adjust preventive measures accordingly. Annual reassessment using the Bronchiectasis Severity Index (BSI), which incorporates clinical, radiological, and microbiological parameters, helps stratify risk and guide therapy intensification. (HRCT) scans may be performed annually or as indicated in moderate-to-severe cases to evaluate structural changes, though limits routine use; alternatives include serial and symptom tracking. This proactive approach enables timely interventions to preserve lung function and avert complications such as .

Management and Treatment

Airway Clearance Techniques

Airway clearance techniques (ACTs) form a of non-pharmacological for bronchiectasis, aiming to mobilize and remove retained secretions from the airways to reduce risk, improve lung function, and enhance . These techniques address the viscous hypersecretion characteristic of the condition, which impairs and perpetuates a cycle of and damage. Regular use of ACTs has been shown to increase expectoration and decrease frequency in stable patients. Physiotherapy-based ACTs, such as the active cycle of technique (ACBT), involve a sequence of control, thoracic expansion exercises, and forced expiration to facilitate mobilization without mechanical aids. ACBT is effective in increasing expectorated volume, reducing viscoelasticity, and alleviating symptoms like dyspnea in adults with bronchiectasis. It outperforms techniques like timed incentive in single sessions by enhancing clearance during treatment. Positive expiratory pressure (PEP) therapy, another physiotherapy approach, uses devices to generate resistance during , preventing airway collapse and promoting collateral ventilation to loosen secretions. PEP devices have demonstrated benefits in improving efficacy and expectoration compared to no treatment, with studies showing significant increases in volume post-session. Specialized devices enhance the efficacy of ACTs for patients with limited mobility or severe disease. Oscillatory PEP devices, such as the , combine PEP with high-frequency s to vibrate and shear from airway walls, improving secretion transport more effectively than standard PEP in some cases. These handheld tools are portable and user-friendly, leading to better clearance and quality-of-life scores in stable non-cystic bronchiectasis. High-frequency chest wall (HFCWO), delivered via an inflatable vest connected to a generator, applies external vibrations to the at frequencies of 5-25 Hz, dislodging and aiding its expulsion through coughing. HFCWO has been associated with reduced hospitalizations, antibiotic use, and improved self-reported outcomes in real-world bronchiectasis cohorts. Postural drainage leverages gravity to drain secretions from specific lobes by positioning the patient with the affected area uppermost, often combined with percussion or for enhanced effect. Positions are tailored to bronchiectasis distribution, such as side-lying with the upper lobe elevated for apical involvement or prone with hips raised for basal segments; the is particularly effective for lower lobe clearance. This technique is simple, cost-free, and suitable for home use, though it requires instruction to avoid discomfort. Patient education is essential for optimizing ACT adherence, which remains low at approximately 41% for airway clearance in bronchiectasis, influenced by factors like perceived burden and lack of tailored training. Structured programs emphasizing technique demonstration, of sputum volume, and integration into daily routines improve compliance and long-term outcomes, with video consultations showing high satisfaction and in remote settings. Adherence is higher among those with more severe symptoms, underscoring the need for personalized to empower self-management.

Pharmacological Therapies

Pharmacological therapies for bronchiectasis primarily target chronic airway , , mucus hypersecretion, and airflow obstruction to reduce exacerbations, improve lung function, and enhance . Antibiotics form the cornerstone, with choices guided by and exacerbation frequency. Long-term antibiotic therapy is recommended for patients with frequent (≥3 per year) or chronic bacterial colonization, particularly . Inhaled antibiotics, such as tobramycin inhalation solution (300 mg twice daily for 28 days on/off cycles), reduce bacterial load in and have shown a 30% reduction in exacerbations in patients with chronic P. aeruginosa , based on pooled data from randomized trials. The RESPIRE trials demonstrated sustained reductions in Pseudomonas density without significant overall exacerbation benefit in broader non-CF bronchiectasis populations, but guidelines endorse their use in pathogen-specific cases due to improved symptom control and fewer hospitalizations. Treatment of exacerbations in bronchiectasis, including the dry variant characterized by little to no sputum production, follows standard bronchiectasis guidelines in both the US and UK, with no specific separate protocols identified for the "dry" subtype. Exacerbations are treated with antibiotics (oral or IV depending on severity) if bacterial infection is suspected, based on worsening symptoms such as cough, dyspnea, or fatigue; duration is typically 10-14 days. In the UK, the British Thoracic Society (BTS) guidelines (2018) emphasize prompt antibiotics for acute deteriorations. In the US, management aligns with international standards, often referencing European Respiratory Society (ERS) guidelines recommending 14 days of antibiotics. Airway clearance techniques are recommended even in dry cases during exacerbations, along with supportive care like bronchodilators if needed. For acute requiring hospitalization, intravenous antibiotics like ceftazidime or piperacillin-tazobactam are standard, targeting isolated pathogens and typically administered for 10-14 days to resolve symptoms and prevent progression. Anti-inflammatory agents address persistent airway inflammation beyond infection control. Low-dose macrolides, such as erythromycin (250 mg daily), exert immunomodulatory effects and are recommended for adults with ≥2 exacerbations per year; the BLESS trial reported a 35% reduction in exacerbation frequency over 12 months compared to , alongside improved scores. Emerging biologics target eosinophilic subsets; (anti-IL-5 , 100 mg subcutaneously every 4 weeks) has shown symptom improvement and reduced infectious exacerbations in small cohorts of patients with severe and comorbid bronchiectasis. Brensocatib, a dipeptidyl peptidase 1 inhibitor (10-25 mg daily oral), inhibits serine proteases and reduced pulmonary exacerbations by 18.3% (25 mg dose) versus in the phase 3 ASPEN trial (n=1681), with additional slowing of function decline; it received FDA approval in 2025 as the first specific therapy for non-CF bronchiectasis. Bronchodilators and mucoactive agents alleviate airflow limitation and facilitate clearance. Inhaled short-acting beta-agonists (e.g., 2.5-5 mg nebulized) or long-acting muscarinic antagonists (e.g., tiotropium 18 mcg daily) are used in patients with reversible obstruction (≥12% FEV1 improvement post-bronchodilator), improving exercise tolerance per ERS guidelines. Nebulized hypertonic saline (7%, 4 mL twice daily) hydrates airway surfaces and enhances ; older randomized trials report 10-15% absolute improvements in FEV1, but a large phase 3 trial in 2025 found no significant reduction in exacerbation rates over 52 weeks in non-CF bronchiectasis. In bronchiectasis associated with (CF), CFTR modulators address underlying ion channel defects in patients with eligible mutations. Elexacaftor-tezacaftor-ivacaftor (150/100/75 mg oral twice daily, known as Trikafta) improves CFTR function, leading to 10-14% mean FEV1 gains and 63% reduction in exacerbations in CF populations; recent 2025 data extend benefits to non-CF bronchiectasis with amenable CFTR variants (e.g., F508del), showing enhanced function, symptom relief, and fewer annual exacerbations in small cohorts. Pathogen-specific targeting complements these therapies, as detailed in inflammatory processes.

Surgical and Interventional Options

Surgical resection remains a for managing localized bronchiectasis refractory to conservative measures, particularly in cases involving recurrent s or significant . , which involves removal of the affected lobe, is the preferred procedure when is confined to one or two lobes, allowing preservation of functional tissue. Complete resection of bronchiectatic areas achieves symptom relief or cure in 70-80% of patients, with lower rates of recurrence and improved compared to incomplete resections. Operative mortality is low (0-2%), though morbidity from complications such as prolonged air leak or occurs in 10-20% of cases, emphasizing the need for careful patient selection based on preoperative and pulmonary function. For patients with end-stage diffuse bronchiectasis and advanced , lung offers a definitive treatment option after failure of maximal medical therapy. Bilateral lung is typically performed, with indications including severe airflow obstruction, frequent exacerbations, and . Five-year post-transplant survival in adults with non-cystic fibrosis bronchiectasis reaches approximately 61%, comparable to outcomes in other chronic lung diseases, though early mortality from remains a concern. Long-term success depends on multidisciplinary care to manage rejection and infections, with many recipients experiencing substantial improvements in exercise capacity and quality of life.30064-6/fulltext) Bronchoscopic therapies provide less invasive alternatives for targeted intervention in bronchiectasis, especially for localized or structural abnormalities contributing to symptoms. Endobronchial valve placement involves deploying one-way valves to isolate hyperinflated segments, promoting and redistribution of ventilation, while coils compress diseased tissue to achieve volume reduction. These approaches are suitable for patients with comorbid or heterogeneous disease distribution. Recent studies from 2023-2025 demonstrate that endobronchial valves can reduce frequency by up to 50% in selected cases with complete lobar occlusion, alongside improvements in dyspnea and function. Complications such as (up to 25%) or valve migration are manageable bronchoscopically, making this a bridge to transplantation in advanced disease. Palliative interventional procedures are crucial for life-threatening complications like massive , which arises from hypertrophied bronchial arteries in bronchiectasis. Bronchial artery (BAE) entails catheter-directed occlusion of aberrant vessels using particles or coils, achieving immediate in over 90% of cases. For bronchiectasis-related , BAE controls massive bleeding effectively with low procedural mortality (<1%), though recurrence occurs in 10-30% within the first year, often necessitating repeat interventions. This technique is preferred over in unstable patients due to its minimally invasive nature and rapid recovery.

Prognosis and Complications

Factors Affecting Outcomes

Several validated prognostic scores assist in predicting mortality and disease progression in patients with bronchiectasis, enabling stratification for personalized management. The FACED score, which incorporates forced expiratory volume in 1 second (FEV1), age, chronic colonization, radiological extension of , and dyspnea severity, stratifies patients into mild, moderate, and severe categories with 5-year mortality rates of approximately 3.7%, 20.7%, and 48.5%, respectively. Similarly, the Bronchiectasis Severity Index (BSI) integrates nine factors including age, FEV1, dyspnea, sputum purulence, exacerbations, , colonization, hospitalization history, and lung function to predict 1-year mortality (ranging from 0-2.8% in mild cases to higher rates in severe ) and overall 5-year mortality of 3-40%. Modifiable factors significantly influence outcomes, with chronic isolation of approximately doubling the risk of hospitalization for acute exacerbations compared to non-colonized patients. exacerbates disease progression by promoting airway . Demographic characteristics also play a key role, as patients over 65 years exhibit roughly twice the mortality risk compared to younger adults, driven by comorbidities and reduced physiological reserve. Long-term survival has improved markedly in contemporary cohorts, reflecting advances in care. Co-infection with (NTM) is associated with poorer prognosis, including higher mortality and rates, affecting up to 20% of patients in some cohorts as of 2023.

Common Complications

One of the most common complications of bronchiectasis is recurrent , which arises from the structural damage to the airways that impairs and fosters persistent bacterial colonization, facilitating repeated infectious episodes that manifest as lobar consolidation and contribute to progressive . This vulnerability leads to frequent requiring antibiotic therapy, with patients often experiencing multiple episodes annually due to the cycle of inflammation and infection. Hemoptysis and represent significant pulmonary complications, where results from the erosion of hypertrophied bronchial arteries and mucosal vessels amid chronic inflammation and within the dilated bronchi. Massive , defined as life-threatening bleeding exceeding 100-600 mL in 24 hours, affects approximately 16% of patients with bronchiectasis and can lead to acute airway compromise or if untreated. develops through localized tissue from severe, untreated , often involving anaerobic , and is recognized by symptoms of foul-smelling , fever, and showing cavitary lesions. Respiratory failure is a severe end-stage complication in advanced bronchiectasis, driven by progressive airflow obstruction, ventilation-perfusion mismatch, and chronic that culminates in hypercapnic or requiring . This often coexists with cor pulmonale, where sustained from hypoxic and vascular remodeling imposes right ventricular strain, leading to ; recognition involves showing right ventricular hypertrophy and dilation alongside clinical signs of and exertional dyspnea. Extrapulmonary complications include secondary , which emerges from prolonged depositing amyloid A protein in organs like the kidneys, resulting in with and renal dysfunction; though now less common due to improved management, it affects a subset of patients with longstanding, severe . Recent observations highlight rising post-viral complications, such as organizing following infections like , characterized by intra-alveolar fibroblastic plugs and patchy consolidation on imaging, particularly in those with preexisting bronchial vulnerability.

Epidemiology

Global Prevalence and Distribution

Bronchiectasis exhibits significant global variability in prevalence, with estimates ranging from 50 to 1000 cases per 100,000 individuals due to differences in diagnostic practices and reporting. In high-income regions such as Europe and Australia, reported prevalence is higher, typically between 67 and 566 per 100,000, reflecting improved access to high-resolution computed tomography (HRCT) imaging; for instance, rates reach 566 per 100,000 in the United Kingdom, while lower figures like 67 per 100,000 are noted in Germany. In contrast, prevalence appears underreported in low- and middle-income regions like parts of Asia and Africa, with estimates varying widely (e.g., below 50 per 100,000 in some areas to over 400 per 100,000 in others in Asia), attributed to limited diagnostic resources and underrecognition of the condition despite high burdens from post-infectious etiologies such as tuberculosis. A 2024 meta-analysis pooling data from multiple countries estimated a global adult prevalence of 680 per 100,000 (95% CI: 634–727), underscoring the disease's commonality but highlighting regional disparities. A 2025 narrative review notes declining prevalence in certain high-income cohorts born after the 1970s (e.g., 11.0 per 1,000 born in the 1980s in the US), while pediatric registries highlight increasing recognition in children globally. Incidence rates for bronchiectasis also vary geographically, ranging from 8 to 29 new cases per 100,000 adults annually, with higher figures in (29 per 100,000 ) and more stable but lower rates in (around 19 per 100,000 in ). Overall, incidence has been increasing worldwide at approximately 2-3% per year, driven by aging populations, better detection through imaging, and rising awareness, though rates have shown steeper annual growth of about 8%. Geographic variations are pronounced in indigenous populations, where prevalence is substantially elevated due to factors like recurrent childhood infections and environmental exposures; for example, Native children in the experience rates up to four times higher than the general population, with approximately 1 in 63 affected. Similar disparities occur among Australian Aboriginal and Māori communities, where bronchiectasis is more common and presents earlier in life. Recent trends indicate a post-2020 surge in bronchiectasis cases associated with , with approximately 16.8% (95% CI: 9.1–26.1%) of survivors showing bronchiectasis on post-infection imaging, contributing to the global rise in non-cystic fibrosis bronchiectasis diagnoses.

Risk Factors in Populations

Bronchiectasis predominantly affects older adults, with peak onset occurring between the ages of 50 and 70 years, as evidenced by cohort studies showing a median age of 67 years at . rates rise substantially with advancing age, from approximately 7 per 100,000 in individuals aged 18–34 years to over 800 per 100,000 in those aged 75 years and older, reflecting cumulative exposures to respiratory insults over time. In non-cystic fibrosis cases, there is a slight female predominance, with a female-to-male of about 1.5:1; estimates indicate 566 cases per 100,000 women compared to 485 per 100,000 men in certain populations, potentially linked to factors such as longer endogenous exposure or differences in immune responses to infections. Socioeconomic status significantly influences bronchiectasis susceptibility, with higher rates observed in low-income settings where barriers to exacerbate risks. In urban poor communities, inadequate coverage against childhood respiratory pathogens, such as type b and pneumococcus, contributes to recurrent infections that can lead to bronchiectasis; studies in low- and middle-income countries report prevalence up to three times higher among disadvantaged groups due to these gaps. Environmental pollution, including indoor smoke and outdoor particulate matter, further amplifies vulnerability in these populations, as short-term exposures have been associated with increased mortality and disease progression in resource-limited urban areas. Comorbidities like (COPD) substantially elevate bronchiectasis risk through shared etiological pathways. Overlap occurs in approximately 30% of COPD patients, driven by common exposures such as and , which impair and promote chronic inflammation in the airways. This bronchiectasis-COPD overlap syndrome heightens susceptibility to exacerbations and severe airflow limitation, underscoring the need for targeted screening in at-risk individuals with . Ethnic variations also play a role in bronchiectasis distribution, with elevated rates among indigenous populations such as Maori and Pacific Islanders. Hospital admission rates for bronchiectasis are 3.5 to 5 times higher in Maori compared to non-Maori , and similarly disproportionate among Pacific Islanders, who represent 20–26% of cases despite comprising smaller population shares. These disparities arise from intertwined genetic predispositions—such as variations in genes—and environmental factors, including , poor , and limited access to early interventions in these communities. These population-specific risks contribute to the heterogeneous global prevalence patterns of bronchiectasis.

History

Early Descriptions

The earliest clinical recognition of what is now known as bronchiectasis dates to the , when French physician René-Théophile-Hyacinthe Laënnec provided the first detailed description based on findings and using his newly invented . In his 1819 treatise Traité de l'Auscultation Médiate, Laënnec coined the term "bronchiectasis," derived from the Greek words bronchi (airways) and ektasis (dilation), to describe the irreversible widening of the bronchi associated with chronic suppuration and foul-smelling . He observed these changes in patients with recurrent pulmonary infections, noting the pathological dilation as a consequence of prolonged , often linked to prior respiratory illnesses. Throughout the , bronchiectasis was increasingly documented as a complication of (TB) and other destructive lung conditions, with high mortality rates in the pre-antibiotic era. Physicians like further elaborated on its clinical features in the late 1800s, describing , copious purulent , and as hallmarks, often leading to or secondary infections. A 1940 study of 400 patients reported a mortality rate higher than 30%, with most dying within 2 years of symptom onset and before age 40, primarily from overwhelming infections or cor pulmonale, underscoring the condition's severity before antimicrobial therapies emerged. In the mid-20th century, pathologist Lynne advanced the understanding through histological examinations, establishing definitive criteria for bronchiectasis in by classifying it into cylindrical, varicose, and saccular subtypes based on bronchial dilation severity and loss of muscular and elastic components. Reid's work, correlating gross with bronchographic , highlighted the role of recurrent infections in perpetuating airway destruction, particularly as a of inadequately treated TB, which was a leading cause in that era. These descriptions laid the foundation for recognizing bronchiectasis as a distinct entity beyond mere post-infectious scarring.

Modern Understanding and Advances

The introduction of antibiotics in the 1940s marked a pivotal advancement in bronchiectasis management, dramatically reducing mortality rates from over 30% in untreated cases to significantly lower levels by controlling bacterial infections and preventing exacerbations. Inhaled antibiotics, first explored during this era for chronic airway infections, laid the groundwork for targeted strategies that improved patient survival and . By the 1950s, the association between (CF) and bronchiectasis was firmly established through pathological studies, such as those by Lynne , which characterized the bronchial dilation and mucus plugging in CF as a primary driver of bronchiectasis progression. This recognition shifted focus toward identifying underlying genetic causes, distinguishing CF-related bronchiectasis from other forms and enabling earlier interventions. Advancements in imaging further transformed diagnosis throughout the 20th century. Bronchography, introduced in the 1930s using iodized oil contrasts like Lipiodol, allowed direct visualization of bronchial abnormalities, confirming bronchiectasis in cases previously reliant on clinical symptoms alone. However, its invasiveness limited widespread use until the 1980s, when high-resolution computed tomography (HRCT) emerged as a non-invasive gold standard, providing detailed cross-sectional images that revolutionized accurate detection and extent assessment of bronchiectasis with high sensitivity. Seminal studies in 1986 demonstrated HRCT's superiority over conventional radiography, enabling precise classification of cylindrical, varicose, and cystic subtypes and facilitating timely treatment. In the , real-world data initiatives like the European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) registry, launched in 2012, have provided comprehensive insights into disease characteristics, exacerbations, and management across diverse populations, informing guidelines and highlighting gaps in non-CF bronchiectasis (NCFB) care. For CF-related bronchiectasis, CFTR modulator therapies since 2012 have offered transformative benefits; the triple combination of elexacaftor, tezacaftor, and , approved in 2019, improved percent predicted forced expiratory volume in 1 second (ppFEV1) by approximately 14% in clinical trials and sustained lung function gains in real-world settings through 2025. Recent efforts in 2024–2025 have addressed longstanding unmet needs in NCFB through targeted trials, culminating in the FDA approval of brensocatib, a dipeptidyl peptidase 1 inhibitor, as the first specific to reduce pulmonary exacerbations by up to 20% and slow function decline in phase 3 studies. This milestone, based on the ASPEN trial results, represents a shift toward disease-modifying agents that inhibit neutrophilic , filling critical gaps in therapeutic options beyond antibiotics and airway clearance. Ongoing investigations into biologics, such as anti-IL-33 monoclonal antibodies, continue to explore anti-inflammatory pathways to further mitigate and structural damage in NCFB.

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