An Interesting Case of Subacute Hypersensitivity Pneumonitis

Hypersensitivity pneumonitis (HSP) is the paradigm of lung response to inhaled organic and inorganic substances. It is a relatively rare disease, constituting 2% of cases of interstitial lung diseases. We describe a case of a 55-year-old female with a history of breathlessness, fever, and cough with expectoration for 1 month. She gave a history of similar such episodes on and off for the past 7 years. She was diagnosed with pulmonary tuberculosis 6 years back and was treated, but her breathlessness continued to occur despite treatment. Further workup was suggestive of HSP. The later history of exposure to poultry dust was elicited. She was started on steroid pulse therapy along with maintenance dose, which resulted in symptomatic improvement. She underwent a bronchoscopy and the bronchoalveolar lavage, and a diagnosis of subacute HSP was made. HSP can be mistaken for pulmonary tuberculosis and wrongly treated with antitubercular therapy unless the patient is probed about exposure to various inciting antigens.