CLINICAL HISTORY.—This 7-month-old girl was well until four days prior to admission, when mild diarrhea and symptoms of upper-respiratory tract infection developed; her hemoglobin level was 5.9 gm/100 ml. Her history was unremarkable and there had been no hematochezia or melena, and no bruising, or other bleeding problems. A dietary history revealed that the patient had ingested large amounts of milk (more than 1 qt) daily. She ate few solid foods other than mashed potatoes and gravy. She had been hospitalized in her home community for evaluation of anemia. On several occasions, occult blood had been detected in the stool. A barium double contrast study of the colon was performed (Figure).
Physical Examination.—On admission to our institution, the girl was markedly pale, but physical examination did not reveal any other abnormalities. The hemoglobin level was 5.9 gm/100 ml, the serum iron level 23μg/100 ml, and the total iron-binding capacity