A 58-year-old white woman was admitted to our hospital with complaints of cough and dyspnea starting 2 weeks previously. Despite a 7-day course of azithromycin, her cough persisted and she developed worsening shortness of breath. Past medical history was significant for recently diagnosed melanoma of the foot with metastasis to the inguinal lymph nodes, cryptogenic cirrhosis, hypertension, hyperlipidemia with a history of stroke, and a positive anticardiolipin antibody. Home medications included ursodiol, citalopram, aspirin, amlodipine, ezetimibe, and metoprolol. Her only cancer treatment to date was ipilimumab, which was started 2 months earlier. She had no known drug allergies or environmental exposures and denied any tobacco, illicit drug, or alcohol use.