A 40-year-old woman complains of mid-abdominal pain that began several hours ago. She has vomited once, and the ride to the hospital was very uncomfortable for her. She has felt hot but has not checked her temperature. She denies any diarrhea or blood in her stools. She has a history of diabetes and hypertension and is on metformin, lisinopril, and hydro-chlorothiazide. She denies trauma or dysuria, and she is currently on her menstrual period. Her surgical history is positive only for a laparoscopic cholecystectomy and tubal ligation. On examination she has a temperature of 38.3°C (101°F), a pulse of 96, clear lungs, normal heart, some right flank tenderness, decreased bowel sounds with voluntary guarding diffusely, and more exquisite tenderness in the right lower quadrant. Her white blood cell count is 16,000 with a left shift. A urinalysis and a pregnancy test are both negative.
What would be the next best step?
A. Obtain an abdominal CT scanThis patient has classic signs and symptoms of acute appendicitis. Appropriate historical and laboratory data leading to this suspicion will lead to the correct diagnosis only 75% of the time in the hands of experienced clinicians. Other potential diagnoses would be mesenteric lymphadenitis, pelvic inflammatory disease, a ruptured graafian follicle, or corpus luteum or gastroenteritis. Abdominal CT is readily available in most emergency departments and is highly accurate (95%). Simple abdominal x-rays are not usually helpful in this situation. Abdominal ultrasound requires the patient to have fasted for 6 hours and to have a full bladder to obtain satisfactory images, and while it can be used to detect appendicitis, it depends on the experience of the technician/radiologist. While surgery will be consulted once the diagnosis is confirmed, they should not be called at this point.