Munchausen syndrome by proxy with massive proteinuria and gastrointestinal hemorrhage

A 5-year-old boy presented with acute abdominal pain. Massive proteinuria of 10 g/1.73 m² per day was detected on standard urinalysis. There was no peripheral edema. Serum concentrations of total proteins, lipids, and creatinine and immunological investigations were normal. Two kidney biopsies revealed no abnormalities. Several weeks later he was admitted for intestinal hemorrhage with significant anemia. Endoscopy of the esophagus, stomach, colon, and small bowel (via laparotomy) were normal. Electrophoresis of urine proteins revealed the unusual finding of an albumin fraction of 99.4%. During a routine check-up in the outpatient clinic fresh urine samples were obtained while the boy’s mother was absent. These were all negative for protein. The mother, who was a nurse, finally confessed to adding human albumin to the urine samples.