A 37 yo male, with no prior medical illness, presented with…
A 37 yo male, with no prior medical illness, presented with a 6-month history of episodes of coughing, shortness of breath, and intermittent fever. He suffered from dyspnea on minor exertion. The patient worked in a cattle feed factory and noticed that he had more complaints after his working hours. Bilateral basal lung crackles were noted on physical examination. Pulmonary function tests showed a restrictive pattern. Radiographic imaging showed a diffuse distribution of ill–defined nodules. Photomicrographs of a lung biopsy are shown below: These findings are most consistent with the diagnosis of