Microvillus inclusion disease in two Korean infants

We report two cases of microvillus inclusion disease and these are the first cases in Korea. The two babies (one baby had a sibling who died of diarrhea in the neonatal period) had excreted their stools up to 200 ml/kg per day since several days after birth. Workup's included extensive infectious, immunologic, hormonal and rheumatologic studies, all of which were negative or normal. Diagnosis rested on the ultrastructural finding of intracytoplasmic inclusions that contained intact microvilli on electron microscopy. We tried somatostatin analogue (octreotide, 4 micrograms/kg/day), cholestyramine (up to 4g t.i.d.), steroid (prednisone, 2 mg/kg/day) and intravenous epidermal growth factor (100 ng/kg/hr for 2 weeks), but there was mild improvement with cholestyramine (decrease stool volume) and epidermal growth factor (increase the number of microvilli per cell) but no improvement was noted with the other treatments. Although it is a rare disorder and the prognosis of microvillus inclusion disease is poor, it must be considered if an infant has chronic secretory diarrhea.