Pneumocystis jiroveci pneumonia in an atypical host

• Pneumocystis jiroveci pneumonia (PCP) commonly manifests in the immunocompromised host with human immunodeficiency virus or hematologic malignancies. PCP infection in the solid tumor population is a rare phenomenon, particularly in patients with breast cancer. We describe a case of PCP in a patient with metastatic breast cancer after treatment with bendamustine, a chemotherapeutic agent associated with profound lymphopenia. • In the solid tumor population, risk factors for PCP include lymphopenia, steroid use, dose intensity of chemotherapy, and certain chemotherapeutic agents (eg, bendamustine), which can cause lymphopenia. • As demonstrated by our patient, those patients with solid tumor malignancy and concurrent PCP present atypically, decompensate rapidly, and have high mortality rates, which underscores the importance of making a timely diagnosis. • We will discuss the need to better characterize those non-human immunodeficiency virus immunocompromised patients who have profound and persistent lymphopenia and who may benefit from prophylaxis.