A 77-year-old white woman presented with the chief complaint of constipation. She reported 1 week of urinary frequency, urgency, and dysuria before constipation developed. The patient denied any fever, chills, nausea, or vomiting. Her past medical history was significant for hypertension; she had no history of diabetes mellitus. Physical examination revealed some mild suprapubic tenderness, but findings were otherwise normal. The serum white blood cell count was 14,200/μL. Her serum glucose was 82 mg/dL. An abdominal radiograph demonstrated curvilinear areas of radiolucency of the bladder wall (arrow). Urinalysis was positive for nitrite and leukocyte esterase with 85 white blood cells per high-power field. Urine culture was positive for Escherichia coli, the most commonly identified organism for emphysematous cystitis. The patient was treated with piperacillin/tazobactam administered intravenously, 3.375 g every 6 hours for 4 days, followed by oral cepha lexin, 500 mg every 12 hours for 10 days. Clinical and radiologic improvement was observed.