Abstract
Pneumocystis jiroveci is a fungus that is a common opportunistic infection in immunocompromised patients, especially acquired immunodeficiency syndrome (AIDS) patients. First-line treatment is trimethoprim-sulfamethoxazole (TMP-SMX). We present the case of a 68-year-old male patient found to have AIDS after being non-compliant with human immunodeficiency virus (HIV) medications for 15 years. He had bilateral pneumonia that was found to be Pneumocystis pneumonia (PCP) caused by Pneumocystis jiroveci. He was treated with TMP-SMX and supportive therapy such as supplemental oxygenation and vasopressors. As his oxygen requirements decreased, he was weaned off vasopressors, his mentation improved, and he was subsequently downgraded from the ICU. PCP should be suspected in immunocompromised individuals with pneumonia. In AIDS patients with PCP, TMP-SMX is the treatment of choice. TMP-SMX should be continued prophylactically until CD4 counts improve.