A man with progressive abdominal distension

A 77-year-old man with a history of benign prostate hypertrophy and ischemic heart disease was referred to our emergency department because of progressive abdominal distension, constipation, and leg edema for 1 week. There was no abdominal pain, fever, nausea, vomiting, body weight loss, or dyspnea. The patient had poor appetite and decreased urine output in the past week. On physical examination, the body temperature was 36.6 C. The bowel sound was hyperactive. Distended abdomen without tenderness was detected. Digital examination revealed an enlarged prostate. A kidney ureter bladder radiograph (Fig.