Chronic Cough

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The common cold is the most common cause of a cough.  It usually subsides spontaneously after 2 to 3 weeks. However, a persistent cough may be the first sign of a more serious disease process.

A chronic cough (defined as lasting for more than 8 weeks in adults and more than 4 weeks in children) is one of the most common presenting complaints in ambulatory medical clinics across the country, according to the Centers for Disease Control (CDC).

Though they are a number of different causes for chronic cough, 4 conditions account for the vast majority of cases:

  1. Upper airway cough syndrome (i.e., UACS, previously called “post-nasal drip syndrome”)
  2. Gastroesophageal reflux disease (i.e., GERD or acid reflux) / Laryngo pharyngeal reflux (i.e., LPR)
  3. Asthma
  4. Eosinophilic bronchitis.

Additional causes may include:

  1. Side effects of medications such as ACE (i.e., angiotensin converting enzyme) inhibitors which are typically utilized to treat high blood pressure
  2. Tobacco use
  3. COPD (i.e., chronic obstructive pulmonary disease) which encompasses both emphysema and chronic bronchitis
  4. Sleep apnea

An excessive or chronic cough can seriously impair the quality of life of an individual and lead to vomiting, muscle pain, rib fractures, urinary incontinence, fatigue, syncope, and/or depression.  Some of the “red flags” indicating a more serious issue may include an association of a cough with fever, weight loss, hoarseness, and/or blood in the sputum. When a cause is not obvious, a chest X-ray is usually obtained to rule out common infections, inflammatory conditions, and/or tumors.

UACS:  It is the most common cause of chronic cough.  The condition is a result of inflammation of the tissues inside the nasal cavity (i.e. allergic or non-allergic rhinitis).  The symptoms may include runny nose, nasal congestion, sneezing, and/or post-nasal drip but their absence does not exclude UACS.  Physical examination may reveal a pale and moist lining of the nasal cavity, swelling of turbinate tissues, redness and/or a cobblestoning appearance in the back of the throat.  Apart from specific treatments of identifiable causes, the symptoms can be relieved by a combination of decongestants, antihistamines, nasal sprays (e.g., saline, corticosteroids, antihistamines, anticholinergics).  Improvement in symptoms can take a few weeks after the initiation of treatment.

Asthma and/or COPD:  Close to one fourth of all cases of a chronic cough may be due to asthma.  The diagnosis is suspected when a cough is associated with chest tightness, shortness of breath, and/or wheezing.  However, a cough may be the only manifestation of asthma in some instances (i.e., cough variant asthma). The diagnosis is established by spirometry before and after the inhalation of a bronchodilator medication.  If inconclusive, asthma can be provoked by inhalation of a medication called methacholine, as part of a diagnostic work-up. Treatments may include inhaled corticosteroids, inhaled bronchodilators, oral anti-inflammatory medications, and rarely short courses of oral corticosteroids.  Cough and other asthma symptoms usually respond to therapy in less than a week.

Signs and symptoms suggestive of asthma may also occur in persons with COPD. Spirometry is diagnostic, and purulent sputum production may also be present. Treatment usually includes an inhaled bronchodilator, inhaled anticholinergic, inhaled corticosteroid, and occasionally a 1-2 week course of oral corticosteroids (with or without antibiotics).

Non-asthmatic eosinophilic bronchitis:  This condition is characterized by a chronic cough without evidence of airflow limitation on pulmonary function tests but the presence of eosinophils in the sputum.  This condition does not respond to inhaled bronchodilators but does respond to inhaled corticosteroids. Avoidance strategies are recommended when the inflammation is due to occupational exposure or inhaled allergens.

GERD/LPR:  Suspicion for these conditions arise when symptoms of heartburn, regurgitation, sour taste, and/or hoarseness are associated with a chronic cough. Consensus guidelines recommend empiric therapy for at least eight weeks in conjunction with lifestyle modifications such as dietary changes and weight loss.

Obstructive sleep apnea:  Obstructive sleep apnea usually presents with night time snoring, restless sleep, and/or daytime somnolence, however, cough can be a manifestation is some cases.  CPAP machines help to relieve the obstruction by forcing air through the upper airways.

ACE inhibitors:  A cough may begin as a side effect in about 10 to 20% of patients receiving these medications and is more common in women.  The cough may appear several months after beginning an ACE inhibitor which often makes it more difficult to diagnose. The only treatment of a cough caused by an ACE inhibitor is the discontinuation of the ACE inhibitor.  After discontinuing the ACE inhibitor, it may take 1-2 months for the cough to subside.

Children:

The most common causes of a chronic cough in children 6-14 years of age are asthma, protracted bacterial infections, and UACS.  Bacterial bronchitis generally requires a 2 week course of an antibiotic such as Augmentin in children who are not allergic to penicillins or clavulinic acid, the components of Augmentin.  UACS is rare in children younger than 6 years of age. Exposure to tobacco smoke, pets, and environmental irritants should be minimized. Of note, rarer conditions such as foreign body aspiration, congenital malformations, and certain immune disorders can also cause a chronic cough in children.

The board certified allergists at Black & Kletz Allergy have been diagnosing and treating chronic coughs in both adults and children in patients in the Washington, DC, Northern Virginia, and Maryland metropolitan area for more than 50 years.  Patients are carefully screened for allergies, asthma, GERD, upper respiratory tract infections, medication usage, sinus disease, and other causes of a chronic cough.  Black & Kletz Allergy has 3 offices in the Washington, DC metro area with locations in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. All of our offices have on-site parking and the Washington, DC and McLean, VA offices are Metro accessible.  We offer a free shuttle that runs between our McLean, VA office and the Spring Hill metro station on the silver line.  If you suffer from a chronic or intermittent cough, please call us to make an appointment at one of our conveniently located offices.  Alternatively, you may click Request an Appointment and we will respond within 24 hours by the next business day.  The allergy doctors at Black & Kletz Allergy are confident that we will be able to help you identify the cause of your cough as well as treat the underlying condition in order to terminate your cough.