PATIENT
Ms. V is a 45-year-old woman who comes to see you in the office; she complains of 4 days of diarrhea. She reports feeling tired and weak. She is moving her bowels about 6–8 times a day. She says that she has significant abdominal pain. She came in today because she has begun to pass bloody stools.
On physical exam, her vital signs are temperature, 38.3°C; BP, 130/84 mm Hg; pulse, 90 bpm; RR, 12 breaths per minute. She is orthostatic.
Her abdomen has hyperactive bowel sounds. It is diffusely tender, without peritoneal signs. Her stool is a mixture of soft brown stool and blood.
At this point, what is the leading hypothesis, what are the active alternatives, and is there a must not miss diagnosis? Given this differential diagnosis, what tests should be ordered?