Cough

Cough, a common symptom in general practice, can be caused by a variety of conditions, ranging from benign to serious. It’s classified as:

  • acute (lasting less than three weeks)
  • subacute (three to eight weeks)
  • chronic (more than eight weeks).

Effective management relies on identifying and treating the underlying cause.

Causes

  • Infectious:
    • Acute: Viral upper respiratory infections (common cold), pneumonia, acute bronchitis.
    • Chronic: Tuberculosis, fungal infections.
  • Non-Infectious:
    • Asthma, especially cough-variant asthma.
    • Gastroesophageal reflux disease (GORD).
    • Chronic obstructive pulmonary disease (COPD).
    • Allergic rhinitis and postnasal drip syndrome.
    • Medications, particularly ACE inhibitors.
    • Environmental irritants like smoke or pollutants.
    • Pulmonary conditions like interstitial lung disease, bronchiectasis.
    • Heart failure causing fluid buildup in lungs.
    • Psychogenic cough, often a diagnosis of exclusion.

Diagnosis

  • Clinical History: Duration, nature (dry or productive), associated symptoms (fever, dyspnea, wheezing, heartburn), exposure history, and current medications.
  • Physical Examination: Auscultation of the lungs, examination of the throat and sinuses, and cardiac examination.
  • Investigations:
    • Chest X-ray for suspected pneumonia, bronchitis, or other lung conditions.
    • Pulmonary function tests for asthma or COPD.
    • CT scan of the chest if there is suspicion of more complex lung pathology.
    • Laboratory tests for specific infections or inflammatory markers.

Differential Diagnosis

  • Upper Respiratory Infections: Including viral and bacterial infections.
  • Asthma or COPD: Especially in the presence of wheezing and shortness of breath.
  • GORD: Consider in patients with heartburn or regurgitation symptoms.
  • Heart Failure: Especially in older patients with a history of cardiac issues.
  • Medication-Induced: ACE inhibitors are a common cause.
  • Pulmonary Embolism: Particularly in cases with sudden onset and risk factors for thromboembolism.

Management

  • Addressing Underlying Cause: Key to effective management (e.g., antibiotics for bacterial pneumonia, inhaled corticosteroids for asthma).
  • Symptomatic Treatment:
    • Cough suppressants (e.g., dextromethorphan) for a dry cough.
    • Expectorants (e.g., guaifenesin) for a productive cough.
    • Mucolytics (eg, bromhexine)
  • Home Remedies and Lifestyle Modifications: Adequate hydration, humidifiers, and avoiding irritants.
  • Managing Comorbid Conditions: Like asthma, GORD, or heart failure.
  • Stop ACE Inhibitors: If cough is associated with their use.
  • Referral: To a specialist for chronic or unexplained cough, or if serious underlying pathology is suspected.

Conclusion

Cough is a symptom with a broad differential diagnosis. Management should focus on the underlying cause, with symptomatic treatment as needed. In cases where the diagnosis is unclear, or the cough is persistent, further investigation and specialist referral may be required.