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Catarrh
Catarrh
Catarrh
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Catarrh
Other namesCatarrhal inflammation
Pronunciation
SpecialtyPulmonology

Catarrh (/kəˈtɑːr/ kə-TAR) is an inflammation of mucous membranes in one of the airways or cavities of the body,[1][2] usually with reference to the throat and paranasal sinuses. It can result in a thick exudate of mucus and white blood cells caused by the swelling of the mucous membranes in the head in response to an infection. It is a symptom usually associated with the common cold, pharyngitis, and chesty coughs, but it can also be found in patients with adenoiditis, otitis media, sinusitis or tonsillitis. The phlegm produced by catarrh may either discharge or cause a blockage that may become chronic.

An 1896 ad for Elys Cream Balm, a catarrh remedy

The word "catarrh" was widely used in medicine since before the era of medical science, which explains why it has various senses and in older texts may be synonymous with, or vaguely indistinguishable from, common cold, nasopharyngitis, pharyngitis, rhinitis, or sinusitis. The word is no longer as widely used in American medical practice, mostly because more precise words are available for any particular disease. Indeed, to the extent that it is still used, it is no longer viewed nosologically as a disease entity but instead as a symptom, a sign, or a syndrome of both. The term "catarrh" is found in medical sources from the United Kingdom.[3] The word has also been common in the folk medicine of Appalachia, where medicinal plants have been used to treat the inflammation and drainage associated with the condition.[4]

Clinical relevance

[edit]

Because of the human ear's function of regulating the pressure within the head region, catarrh blockage may also cause discomfort during changes in atmospheric pressure.

Etymology

[edit]

The word "catarrh" comes from 15th-century French catarrhe, Latin catarrhus, and Greek Ancient Greek: καταρρεῖν[5] (katarrhein): kata- meaning "down" and rhein meaning "to flow." The Oxford English Dictionary quotes Thomas Bowes' translation of Pierre de la Primaudaye's The [second part of the] French academic (1594): "Sodainely choked by catarrhs, which like to floods of waters, runner downwards."[6]

See also

[edit]
  • Allergy – Immune system response to a substance that most people tolerate well
  • Allergic rhinitis, also known as Hay fever – Nasal inflammation due to allergens in the air
  • Rhinitis – Irritation and inflammation of the mucous membrane inside the nose
  • Rheum – Mucus naturally discharged from eyes, nose, or mouth during sleep

References

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

Catarrh

View on Grokipedia
from Grokipedia
Catarrh is a common medical condition involving the excessive production and accumulation of in the mucous membranes of the , particularly affecting the , , and sinuses, often leading to a sensation of . The term originates from the phrase meaning "to flow down," reflecting the dripping sensation of from the nasal passages into the . While typically a temporary response to irritation or , chronic catarrh can persist for weeks or longer, impacting daily comfort and breathing. Symptoms of catarrh include a blocked or runny , frequent throat clearing, a persistent , a feeling of a lump in the , and crackling sounds in the ears due to buildup. In acute cases, it often accompanies the or flu, lasting a few days to a week, whereas chronic forms may involve ongoing without fever or other acute signs. The condition can vary in severity, with ranging from clear and thin to thicker and discolored if an is present. Common causes of catarrh encompass viral infections such as the or , allergic reactions to , , or pet dander, and environmental irritants like cigarette smoke or . Other contributing factors include bacterial , nasal polyps, gastroesophageal reflux disease (GERD), and in children, foreign objects lodged in the nose. Hormonal changes or consumption of spicy foods can also trigger episodes by stimulating production. Treatment for catarrh primarily focuses on symptom relief and addressing underlying causes, as it often resolves without intervention. Home remedies include staying hydrated to thin , using a to moisten the air, saline nasal rinses to clear passages, and with salt water to soothe the . Over-the-counter options such as decongestants, antihistamines for allergy-related cases, and nasal sprays can provide additional relief. If symptoms persist beyond a few weeks or are accompanied by severe , fever, or difficulties, medical evaluation is recommended to rule out complications like polyps or infections requiring prescription treatments or .

Definition and Overview

Definition

Catarrh is defined as an of the , particularly those lining the airways of the , typically characterized by excessive production and secretion of . Catarrh is typically a descriptive term for the inflammatory process rather than a specific diagnosis. The term originates from the Greek word katarrhous, meaning "flowing down," reflecting the downward flow of associated with the condition. While often used interchangeably in common parlance, catarrh differs from , which specifically describes the posterior drainage of from the nasal passages into the as a symptom rather than the underlying inflammatory process. Similarly, refers to the that is expectorated, particularly from the , whereas catarrh encompasses the broader and accumulation before expulsion. Catarrh is generally a self-limiting condition that primarily affects the upper , though it may involve adjacent areas such as the sinuses, , or bronchi. Common sites include the and , where the inflamed membranes lead to increased to protect against irritants.

Classification

Catarrh is classified into acute and chronic forms based on the duration of symptoms. Acute catarrh typically lasts a few days to a few weeks and is frequently associated with viral infections, such as those causing the . In contrast, chronic catarrh persists for months or longer and is commonly linked to allergies or environmental irritants, leading to ongoing production. Classification by location distinguishes catarrh affecting different parts of the respiratory tract. Nasal catarrh resembles rhinitis, involving excess mucus in the nasal passages. Sinus catarrh is associated with sinusitis, where inflammation leads to mucus accumulation in the paranasal sinuses. Pharyngeal catarrh manifests as mucus buildup in the throat, often resulting in a sensation of postnasal drip. Bronchial catarrh involves the lower airways, akin to catarrhal bronchitis with inflammation and mucus in the bronchi.

Pathophysiology

Mechanisms of Inflammation

Catarrh involves an inflammatory cascade in the mucous membranes, primarily triggered by exposure to irritants or pathogens, which activates resident immune cells such as mast cells and macrophages. This activation leads to the degranulation of mast cells and the release of pro-inflammatory mediators, including , leukotrienes, and cytokines like TNF-α, IL-6, IL-1β, and IL-8. These cytokines orchestrate the recruitment of additional immune cells, such as and neutrophils, through the upregulation of adhesion molecules like and on endothelial cells. The resulting and increased cause plasma exudation into the tissues, culminating in mucosal and congestion characteristic of catarrhal . A key aspect of this inflammatory response is the hypersecretion of , driven by the and proliferation of specialized cells. , which are mucin-secreting cells embedded in the mucosal , undergo in response to inflammatory signals, leading to excessive production of mucins such as MUC5AC. This process is amplified by cytokines and other mediators that stimulate goblet cell differentiation from precursor cells. Concurrently, submucosal glands, located beneath the in larger airways and nasal passages, increase their secretory activity, contributing to the overall hypersecretion that aims to trap and clear irritants but often results in obstruction. Inflammation further disrupts the epithelial , exacerbating the catarrhal process. Pro-inflammatory and proteases degrade proteins, including , claudins, and zonula occludens-1, which normally seal the paracellular spaces between epithelial cells. This compromise increases mucosal permeability, facilitating the entry of additional antigens and pathogens into the submucosal layers, which in turn amplifies immune cell activation and release, perpetuating a cycle of chronic or recurrent inflammation. Such barrier dysfunction is a central feature in upper respiratory catarrh, linking initial triggers to sustained mucosal responses.

Mucus Production and Clearance

In normal physiological conditions, the mucus layer in the consists primarily of a thin, that protects epithelial surfaces while allowing efficient clearance through coordinated ciliary action. This is predominantly composed of (approximately 95%), electrolytes, and low concentrations of mucins such as MUC5B, maintaining low for optimal mucociliary . During catarrh, triggers and , shifting production from thin serous to thick, mucoid secretions characterized by elevated levels of glycoproteins, particularly MUC5AC. This change is driven by viral or irritant-induced signaling, where MUC5AC expression increases up to several-fold, contributing to hypersecretion and altered gel-forming properties that impede normal flow. Inflammatory mediators, including IL-13 and TNF-α, activate pathways such as and EGFR to upregulate MUC5AC synthesis in response to epithelial injury. Mucus clearance in catarrh is further compromised by ciliary dysfunction, where and direct damage ciliated epithelial cells, reducing beat frequency and coordination essential for mucociliary . This impairment results in mucus stasis, creating an environment conducive to secondary bacterial overgrowth and perpetuating . exacerbates these issues by reducing mucus hydration, increasing its viscosity and promoting persistent as thicker secretions accumulate and resist clearance. In inflamed states, deranged pathways, such as those involving CFTR, lead to hyperconcentrated mucus, further hindering expulsion and amplifying catarrhal symptoms.

Causes

Infectious Etiologies

Catarrh, characterized by inflammation of the mucous membranes in the upper , is most frequently induced by viral infections that target the nasal and pharyngeal epithelia. Among these, rhinoviruses represent the predominant , accounting for 30-50% of cases, which are a primary manifestation of catarrh. These non-enveloped viruses replicate optimally at cooler temperatures in the nasal passages, leading to symptoms such as and . Other significant viral contributors include endemic coronaviruses, which cause approximately 10-30% of upper respiratory infections in adults, often presenting with milder catarrhal symptoms compared to rhinovirus. viruses, while typically associated with more systemic illness, can also initiate catarrh in 5-15% of cases by affecting the upper airways early in infection. Transmission of these viruses primarily occurs through respiratory droplets generated by coughing, sneezing, or talking, which deposit infectious particles onto mucosal surfaces of susceptible individuals. Bacterial involvement in catarrh is generally secondary, arising as superinfections that complicate initial viral insults, particularly in chronic or recurrent cases involving the sinuses. is a common culprit in acute bacterial , a condition often evolving from unresolved viral catarrh, where it invades the and exacerbates production. Similarly, nontypeable frequently contributes to bacterial superinfections, especially in persistent upper respiratory inflammation, by adhering to damaged epithelial cells and promoting further purulent discharge. These pathogens thrive in the nutrient-rich environment created by viral-induced tissue damage, leading to prolonged catarrhal symptoms in vulnerable populations such as children or those with anatomical predispositions. Fungal and parasitic etiologies of catarrh are exceedingly rare and predominantly affect immunocompromised individuals, where opportunistic pathogens exploit impaired host defenses. species, for instance, can cause in patients with or prolonged use, resulting in necrotizing inflammation of the and thick, mucopurulent discharge. Parasitic infections, such as those from like in rare sinonasal cases, similarly manifest in severely immunocompromised hosts but lack widespread documentation in typical catarrh presentations.

Non-Infectious Triggers

Non-infectious triggers of catarrh primarily involve allergic reactions, environmental irritants, and physiological factors that provoke and excessive production in the nasal and pharyngeal mucosa without microbial involvement. These triggers lead to conditions such as allergic and non-allergic , which manifest as catarrhal symptoms including and congestion. Structural abnormalities, such as nasal polyps—soft, noncancerous growths in the nasal lining—can obstruct , promote chronic , and lead to persistent accumulation and catarrh. Foreign bodies lodged in the , particularly in children, may cause mechanical irritation, unilateral discharge, and secondary catarrhal symptoms. Allergic rhinitis represents a key non-infectious trigger, characterized by an IgE-mediated to environmental allergens that sensitize the . Upon re-exposure, allergens bind to IgE on mast cells, releasing and other mediators that cause immediate , , and mucus hypersecretion. Common allergens include from trees, grasses, and weeds, which drive seasonal allergic rhinitis (often termed hay fever), as well as perennial allergens such as dust mites, mold spores, and animal that persist year-round. Seasonal forms typically peak during spring, summer, or fall depending on regional cycles, while perennial rhinitis occurs continuously in sensitized individuals exposed to indoor triggers. This IgE-driven process amplifies local , contributing to chronic catarrh in susceptible populations. Environmental irritants induce non-allergic rhinitis, a form of catarrh triggered by non-immunologic stimuli that directly irritate the nasal lining, leading to neurogenic inflammation and reflex mucus production. Airborne pollutants like tobacco smoke, vehicle exhaust, and industrial smog activate sensory nerves in the mucosa, causing vasodilation and glandular hyperactivity without IgE involvement. Changes in weather, such as exposure to cold, dry air or sudden temperature shifts, similarly provoke these responses by altering mucosal hydration and blood flow, exacerbating catarrhal symptoms in urban or polluted environments. Occupational exposures to chemicals, perfumes, or dust further contribute, highlighting the role of irritants in perpetuating non-infectious catarrh. Other physiological factors, including gastroesophageal reflux and hormonal fluctuations, can also precipitate catarrh by indirectly irritating the upper airway. Laryngopharyngeal reflux (LPR), a variant of gastroesophageal reflux disease, allows acidic gastric contents to reach the pharynx and larynx, eroding the mucosa and stimulating compensatory mucus secretion perceived as postnasal drip. Hormonal changes, particularly during pregnancy, elevate levels of estrogen and progesterone, which relax vascular smooth muscle and promote nasal congestion independent of allergies. This pregnancy rhinitis affects up to 30% of expectant individuals, often resolving postpartum, and underscores the influence of endocrine shifts on catarrhal inflammation. Consumption of spicy foods can trigger gustatory rhinitis through capsaicin-induced stimulation of sensory nerves, leading to reflexive mucus production and acute catarrhal episodes.

Clinical Presentation

Symptoms

Catarrh manifests primarily through of the mucous membranes in the upper , leading to a range of sensory and functional disturbances. The most common symptom is , characterized by a constantly blocked due to swollen tissues and excess production, which can make difficult and create a sensation of stuffiness. often accompanies this, where slowly drips down the back of the , causing irritation and a feeling of something stuck or a lump in the . Patients frequently experience sore throat and the urge for repeated throat clearing as the mucus irritates the pharyngeal lining, leading to discomfort and a persistent desire to swallow or hawk up phlegm. A cough, which may be dry or productive with mucus expectoration, commonly arises from this irritation, particularly in the context of acute episodes triggered by colds or flu. Associated symptoms include headache from sinus pressure, reduced sense of smell and taste due to nasal obstruction, and ear pressure or crackling sensations resulting from Eustachian tube involvement. The presentation varies by duration: acute catarrh typically involves sudden onset of these symptoms, resolving within a few days to weeks as the underlying or irritant subsides, while chronic catarrh features persistent, low-grade symptoms such as ongoing congestion and throat clearing without clear resolution.

Complications

Catarrh, characterized by excessive mucus production and in the upper , can lead to secondary bacterial s when mucus stasis impairs normal drainage and creates an environment conducive to growth. Common complications include acute , where blocked sinuses become infected, due to obstruction allowing fluid accumulation in the , and from irritating the lower airways. Chronic or recurrent catarrh may result in persistent , as ongoing nasal inflammation prevents proper tube ventilation and equalization of pressure, potentially leading to temporary or prolonged from fluid buildup and structural changes. Additionally, from catarrh can reduce nasal airflow during sleep, exacerbating in susceptible individuals by promoting . In individuals predisposed to respiratory conditions, catarrh can trigger rare but significant systemic effects, such as exacerbations of through airway irritation and increased , or worsening of (COPD) by accelerating airflow limitation and promoting further mucus hypersecretion.

Diagnosis

History and Physical Examination

The of catarrh begins with a thorough to characterize the condition's onset, duration, and potential triggers. Clinicians inquire about the abrupt or gradual onset of symptoms, typically noting a duration of 7-10 days for acute cases, though may persist longer. Triggers such as seasonal allergens, viral exposures in crowded settings, or environmental irritants like smoke are explored, alongside associated symptoms including low-grade fever, , , or a of allergies. For instance, recent contact with ill individuals or attendance at daycare may point to infectious origins. Physical examination focuses on the upper to identify signs of . Nasal inspection or reveals mucosal , congestion, and clear or , while throat examination may show and mild pharyngeal . of the lungs assesses for any lower airway involvement, such as wheezing indicating possible extension beyond the nasopharynx. are generally normal, with fever being uncommon in adults but possible in children. Red flags during history or examination prompt urgent evaluation to rule out serious conditions. Unilateral nasal symptoms, such as persistent drainage or obstruction, may suggest structural issues like tumors, while severe unilateral or foul-smelling discharge warrants specialist referral. These findings guide differentiation from common catarrhal symptoms like bilateral and congestion.

Investigative Procedures

Investigative procedures are typically used in cases of chronic, persistent, or catarrh, where the clinical and suggest a need to identify underlying etiologies such as chronic rhinosinusitis or . Diagnosis of catarrh is usually clinical, but if symptoms persist beyond a few weeks, referral to an specialist may be warranted for further evaluation. These tests help confirm infectious, allergic, or structural causes of mucosal inflammation. Imaging modalities play a key role in evaluating chronic catarrh, particularly when symptoms persist beyond 12 weeks. Computed tomography (CT) scans of the sinuses are the preferred method, revealing mucosal thickening, which indicates inflammation of the sinus linings, as well as potential obstructions or polyps. For instance, CT findings in chronic cases often show soft-tissue opacities along sinus walls without air-fluid levels typical of acute infections. Plain X-rays of the sinuses are rarely utilized due to their lower sensitivity but may be employed in select scenarios to detect complications like orbital or intracranial extension in severe cases. Laboratory tests aid in pinpointing specific triggers of catarrh. Allergy testing, including skin prick tests or measurement of serum (IgE) levels, is recommended when is suspected, as it identifies to common aeroallergens like or dust mites. Nasal swabs, obtained via or molecular methods, detect bacterial or viral pathogens in infectious catarrh, guiding targeted antimicrobial therapy if needed. Nasal cytology, involving microscopic examination of scraped or swabbed , is particularly useful for allergic forms, where elevated signify . This test differentiates allergic from non-allergic catarrh by quantifying cell types such as , neutrophils, or mast cells. Endoscopy provides direct visualization of the nasal passages and sinuses. Flexible nasendoscopy, using a thin, fiberoptic scope, allows assessment of inflammatory sites, mucosal , polyps, or discharge, often performed in outpatient settings to evaluate chronic or catarrh. This procedure is minimally invasive, typically lasting 5-10 minutes, and can guide if neoplastic changes are suspected.

Management and Treatment

Acute Management

Acute management of catarrh focuses on providing symptomatic relief during short-term episodes, which typically involve sudden , , and hypersecretion. Over-the-counter oral decongestants such as can help reduce by constricting blood vessels in the ; use is recommended for short-term relief (up to 7 days) to minimize side effects like or elevated . Topical nasal decongestants should be limited to 3-5 days to prevent rebound congestion or . For cases with an allergic component, first-generation antihistamines like diphenhydramine or second-generation options such as loratadine may alleviate symptoms including sneezing and itchy eyes by blocking effects. Saline , using a neti pot or with isotonic saline solution, effectively clears and irritants from the nasal passages, reducing symptom severity in acute upper respiratory infections. Supportive measures play a crucial role in easing discomfort and promoting recovery. Adequate hydration through increased fluid intake thins secretions, facilitating easier clearance from the airways. Using a cool-mist adds moisture to the air, which can soothe irritated nasal membranes and alleviate congestion, though regular cleaning is essential to prevent microbial growth. Rest is recommended to conserve energy and support the , while avoiding environmental irritants such as tobacco smoke helps prevent exacerbation of . Medical attention should be sought if symptoms persist beyond 10 days, as this may indicate a secondary bacterial or other complication. Similarly, a fever exceeding 101°F (38.3°C) warrants evaluation to rule out more serious underlying conditions.

Chronic Management

For persistent catarrh, often manifesting as chronic with ongoing production and nasal , prescription medications target underlying and viscosity. Intranasal corticosteroids, such as fluticasone propionate, are first-line therapies that reduce , , and by suppressing inflammatory responses in the . Clinical trials have demonstrated their efficacy in improving symptoms of chronic nonallergic and allergic over extended periods, with once-daily dosing minimizing systemic side effects. For allergic etiologies, leukotriene receptor antagonists like provide adjunctive relief by blocking -mediated , particularly in patients with coexisting or seasonal exacerbations. Mucolytics, including guaifenesin, help thin excessive to facilitate clearance, showing objective improvements in pediatric chronic cases through enhanced expectoration and reduced . Lifestyle modifications form the cornerstone of long-term management, emphasizing prevention of triggers and maintenance of nasal health. avoidance strategies, such as using air purifiers, encasing mattresses in covers, and minimizing exposure to or dust mites, significantly alleviate symptoms in allergic chronic rhinitis by reducing antigenic stimulation. Regular nasal routines, particularly saline with neti pots or squeeze bottles, promote , dilute allergens, and decrease inflammation without medication risks; guidelines recommend daily use for chronic cases to sustain symptom control. is crucial, as exposure exacerbates mucosal irritation and hypersecretion; studies indicate that quitting leads to progressive reversal of symptoms, with notable improvements in sinonasal within years of abstinence. When symptoms persist despite optimized and measures, specialist referral is warranted to address potential structural issues or refractory allergies. Patients with chronic sinus involvement, such as recurrent infections or nasal polyps, should be referred to an ear, nose, and throat () specialist for evaluation, including or , to rule out complications like obstructive . For severe allergic catarrh unresponsive to standard treatments, referral to an allergist for —via subcutaneous injections or sublingual tablets—is recommended, as it induces long-term tolerance and reduces reliance on daily medications.

Historical and Etymological Context

Etymology

The term "catarrh" originates from the katárrhoos, a compound of kata- ("down") and rhein ("to flow"), literally meaning "a flowing down." This etymology reflects the early medical concept of humors descending from the head, as first described by around 400 BCE in his writings on humoral , where katárrhoos denoted a non-technical flux of bodily fluids causing respiratory symptoms. The word evolved through as catarrhus, adopting a more precise technical sense under the influence of (c. 129–216 CE), who defined it as a specific downward flow of altered humors from the to the lungs, often triggered by and resulting in inflammation-like conditions such as hoarseness and . By the Middle French period, it appeared as catarrhe, entering English in the early via medical texts, where it retained its humoral connotations of mucous discharge from colds or chest ailments. In the , as humoral theory waned with advances in and , "catarrh" shifted in from a broad description of humoral to a specific term for of mucous membranes, often associated with infectious processes and excessive , as seen in updated lexicons like Robert Hooper's Medical Dictionary (1848).

Historical Perspectives

In ancient medicine, the concept of catarrh originated with Hippocratic writings, where the term "katarrhoos" described a downward flow of humors from the head, reflecting the of four bodily humors—blood, , yellow bile, and black bile—that needed to remain balanced for health. This view positioned catarrh as a symptom of humoral imbalance rather than a distinct disease. , in the 2nd century CE, expanded on this by linking catarrh to cold and damp environmental influences that affected the , causing it to produce excessive, unbalanced that descended into the , leading to symptoms like coughing and hoarseness. By the 18th and 19th centuries, catarrh had evolved into "catarrhal fever," a term applied to outbreaks resembling , characterized by fever, , and nasal discharge. Treatments during this period often included to restore humoral balance and reduce , as well as to combat feverish symptoms, though these were applied broadly to febrile conditions without specific targeting of catarrh's underlying causes. By the early 1800s, medical observers increasingly recognized contagion as a mechanism for its spread, marking a shift from purely environmental or humoral explanations toward infectious theories, particularly in descriptions of waves in Britain. In the , the understanding of catarrh transformed with the identification of viral pathogens; human rhinoviruses, discovered in the through efforts to pinpoint the cause of the , established a microbial for many cases previously labeled as catarrh. This breakthrough, along with advances in , led to a decline in the broad use of "catarrh" as a diagnostic term, with medical literature favoring more precise classifications like for inflammatory nasal conditions.

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