Unusual trifecta of infections, aspiration, and metastatic prostatic adenocarcinoma in a bronchoalveolar lavage specimen

Bronchoalveolar lavage (BAL) is a useful procedure to evaluate lung infiltrates in order to identify infection, foreign body aspiration, and neoplasms. However, it is indeed unusual to find all three in the same sample. We report such a case in a 68-year-old male with a history of metastatic prostate adenocarcinoma and longstanding chronic obstructive pulmonary disease who presented with features of pneumonia. BAL revealed Aspergillus and parainfluenza infections, food particle aspiration pneumonia, as well as metastatic prostatic adenocarcinoma. The food particles were initially confused for yeast infection, but we finally identified them as nut products. This may be the first documented case of nut product aspiration diagnosed on BAL. The potential pitfalls that may complicate the evaluation are also discussed.