Laboratory studies show hemoglobin

A 24-year-old man sees his physician because of abdominal pain and increasing fatigue that has developed over the past 6 months. On physical examination, he is afebrile and appears pale. On palpation, there is mild pain in the right lower quadrant of the abdomen. There are no masses, and bowel sounds are active. Laboratory studies show hemoglobin,
8.9 g/dL; hematocrit, 26.7%; MCV, 74 µm3
; platelet count, 255,000/mm3
; and WBC count, 7780/mm3
. Upper
gastrointestinal endoscopy and colonoscopy showed no lesions. One month later, the patient continues to experience the
same abdominal pain. Which of the following is most likely to cause this patient’s illness?
□ (A) Acute appendicitis
□ (B) Angiodysplasia
□ © Celiac sprue
□ (D) Diverticulosis
□ (E) Giardiasis
□ (F) Meckel diverticulum