A Case of Histoplasmosis Mimicking Primary Lung Cancer With Liver Metastasis.

Histoplasmosis is usually self-limiting in healthy individuals but often fatal in immunocompromised patients. It can mimic primary lung malignancy and liver metastasis, causing a delay in appropriate therapy. We report a case of a 58-year-old male, with a 20 pack-year smoking habit, who presented with a three-week history of persistent fevers and productive cough with night sweats. Computed tomography (CT) scan of chest, abdomen and pelvis showed findings suggestive for primary lung malignancy associated with liver metastasis. Liver biopsy showed budding yeast. Bronchoalveolar lavage (BAL) fluid grew fungal organisms. Urine and serology were positive for histoplasmosis. Patient was pancytopenic, hence, we decided to evaluate further with a bone marrow biopsy which revealed underlying hairy cell leukemia. In the case of disseminated histoplasmosis, a high degree of suspicion towards any immunosuppressive condition should be entertained and any signs should be promptly investigated.