A 61-year-old farmer comes to the physician because of a 3-month history of progressively worsening cough and shortness of breath. He has had a 7.5-kg (16.5-lb) weight loss during this period. He smokes occasionally and does not drink alcohol. Physical examination shows clubbing of the fingers. End-inspiratory crackles are heard in both lower lung fields. An x-ray of the chest shows bilateral reticulonodular densities with interstitial fibrosis. Bronchioalveolar lavage reveals 50% of cells being lymphocytes. Which of the following is the most likely diagnosis?

Question

A 61-year-old farmer comes to the physician because of a 3-month history of progressively worsening cough and shortness of breath. He has had a 7.5-kg (16.5-lb) weight loss during this period. He smokes occasionally and does not drink alcohol. Physical examination shows clubbing of the fingers. End-inspiratory crackles are heard in both lower lung fields. An x-ray of the chest shows bilateral reticulonodular densities with interstitial fibrosis. Bronchioalveolar lavage reveals >50% of cells being lymphocytes.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

Eductional Objective: Hypersensitivity pneumonitis results from an exaggerated immunologic response to an inhaled antigen (eg, mold, animal protein), and presents with cough and dyspnea of variable acuity.  Bronchoalveolar lavage typically shows high relative lymphocyte count (eg, >20%), which helps support the diagnosis.

A 61-Year-Old Farmer Comes to the Physician Because of a 3-Month