A 23-year-old male with an over 10-year history of chronic iron-deficiency anemia and gastroschisis at birth was initially evaluated at an outpatient Gastroenterology clinic with complaints of generalized malaise and fatigue lasting for several days. Although he denied abdominal pain, he had experienced intermittent bloating and epigastric discomfort for several years. He also reported chronic diarrhea, which he described as foul smelling, loose stools that occurred three to six times per day for several years. He denied fevers, chills, nausea, vomiting, hematemesis, or rectal bleeding. Additionally, he denied dyspnea on exertion or chest discomfort. On examination, tachycardia and normotension were noted. A hemoglobin of 4.4 g/dL prompted admission for further evaluation. His past medical history included asthma. The patient had been hospitalized for 3 months after birth (at 36 weeks gestation), largely due to an inability to tolerate oral intake, having received total parenteral nutrition prior to being discharged tolerating oral feeds. Charts from that time noted that he ‘‘...had gastroschisis with intestine, spleen and stomach outside of the abdomen.’’ A few days after birth, he underwent non-resective surgical repair. Intraoperatively, there was no evidence of intestinal atresia. At the age of five, he had one episode of a small bowel obstruction that resolved with medical management. An upper gastrointestinal series (UGIS) with small bowel follow through (SBFT) at that time showed slightly dilated small bowel segments with normal transit time throughout. In 1994, at the age of six, his hemoglobin and mean corpuscular volume (MCV) were within normal limits. Nevertheless, even in 2001, the patient had a history of heme-positive stool, along with bloating, diarrhea, and anemia (hemoglobin 9.1 g/dL and MCV 60). His anemia was evaluated at that time with panendoscopy without abnormal findings. The duodenum was reported as being ‘‘patulous.’’ Biopsies revealed mild chronic active gastritis (antral biopsies were negative for Helicobacter pylori), mild reflux esophagitis, and a normal duodenum. Biopsies throughout the right and left colon were normal. Overall, his endoscopic evaluation did not reveal any abnormalities that explained his anemia. He was prescribed oral iron replacement therapy, which, however, was not tolerated and thus not taken regularly. Given his history of asthma and poor growth as a child, he was evaluated for cystic fibrosis (CF) with sweat chloride and genetic testing which were normal. In 2001 another UGIS with SBFT showed a somewhat dilated distal jejunum. Pancreatic enzyme supplements were prescribed for unclear reasons, which, however, initially improved his bloating and diarrhea. By 2004, the diarrhea recurred with non-bloody, loose stools reported two to three times a week. There was no clear explanation for the patient’s diarrhea, anemia, or hemepositive stools; he was lost to follow-up until being seen at our institution. The patient’s social history was unremarkable in that he denied any drug, alcohol, or tobacco use. He also denied foreign travel or unusual environmental exposures. He did not have any pertinent family history; his three siblings S. R. Sinha (&) G. Triadafilopoulos N. Shah Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University Medical Center, 300 Pasteur Dr., Always Bldg. M211, Stanford, CA 94305-5187, USA e-mail: sidsinha@stanford.edu