2. A patient with persistent dry cough.
Case history- A 55 years old male presents with dry cough for 4 months. He gives no history of fever, breathlessness but he suffers from high BP. There is no abnormality on chest examination and chest X-ray.
What D/D would you consider?
ACE inhibitor induced cough
Postnasal drip syndrome
Cough variant asthma
What key questions would you ask?
When is cough more?
more at night- Cough variant asthma
more at daytime, h/o attempt to clear throat- Postnasal drip syndrome
H/O atopy such as allergic rhinitis, eczema- Cough variant asthma
Family history of atopy- Cough variant asthma
Drug history- ACE inhibitor e.g. lisinopril or ARB e.g. losartan taking for his hypertension
What will you examine?
Inspection of posterior pharyngeal wall reveals cobble stone appearance and track of purulent discharge from posterior nares- Postnasal drip syndrome
Otherwise, examination is normal.
ACE inhibitor induced cough- ACE inhibitor or ARB may cause cough in a few percentage of patient taking these drugs by interfering bradykinin metabolism. Cough is typically dry and distressing.
Treatment-
- Cessation of ACE inhibitor or ARB
- Antihistamine may help
- Cough usually improve but may persist for months even after cessasion of drugs.
Postnasal drip syndrome- It occurs due to chronic sinusitis or rhinosinusitis which leads to persistent discharge through posterior nares that irritates the throat producing cough.
Treatment- corticosteroid nasal spray will relieve the symptom.
Cough variant asthma– It occurs usually in atopic person (atopy means excessive production of IgE to naturally encountered antigen). Patient presents with cough but no breathlessness, tightness and wheeze (i.e. features of bronchial asthma). Majority of patients ultimately develop bronchial asthma.
Treatment– Bronchodilator inhaler and/or inhaled corticosteroid.