Background: A 22-year-old female presented with edema, diarrhea, hypoalbuminemia and pancytopenia. She had previously been diagnosed with congenital disorder of glycosylation type Ib, and had a history of congenital hepatic fibrosis, portal hypertension and esophageal varices. In the past she had refused mannose therapy because of associated diarrhea and abdominal pain. Investigations: Laboratory examinations, abdominal ultrasonography, bacterial and viral cultures of blood, urine and stools, double-balloon enteroscopy and fecal excretion test using51Cr-labeled albumin. Diagnosis: Protein-losing enteropathy. Management: Infusion of albumin followed by intravenous and subcutaneous therapy with unfractionated heparin.