title: Microvillous atrophy: atypical presentations.
abstract: OBJECTIVE
  Microvillous inclusion disease (MVID) is a cause of intractable diarrhea in infancy. In its classic form, the disease is characterized by a severe persistent watery diarrhea starting within the first days of life. Parenteral nutrition and small bowel transplantation are the only known treatments for the affected children. Histologically, periodic acid-Schiff (PAS) staining shows accumulation of periodic acid-Schiff-positive staining material along the apical pole of enterocytes, whereas transmission electron microscopy exhibits microvillus inclusion bodies within the cytoplasm of enterocytes with rarefied and shortened microvilli and secretory granules. The objective of this work was to explore clinical, morphological, and genetic findings in cases of MVID with unusual presentations.
  
  
  METHODS
  Clinical, histological, and genetic findings are reported for 8 cases of MVID with atypical presentation.
  
  
  RESULTS
  The diarrhea started after several months in 3 cases. It was usually less abundant and 3 patients were weaned off parenteral nutrition. None required intestinal transplantation. Three patients experienced malformations, dysmorphy, sensory disabilities, and severe mental retardation. One had a hydrocephaly. Three patients had a cholestasis with low γ-glutamyl transferase levels. Light microscopy showed histological abnormalities consistent with MVID in all of the cases, but the lesions were sometimes focal or delayed. Transmission electron microscopy retrieved some criteria of MVID in 4 patients. Finally, 6 patients were homozygotes or compound heterozygotes for MYO5B mutations.
  
  
  CONCLUSIONS
  This study extends the spectrum of MVID to less severe clinical presentations.
authors.affiliation: *Université Paris-Diderot-Sorbonne Paris Cité, UMR 1149 †Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré ‡INSERM, UMR1149, Paris §Department of Electron Microscopy, Université François Rabelais, Tours ||Assistance Publique-Hôpitaux de Paris, Hôpital Necker Enfants-Malades ¶Université Paris Descartes-Sorbonne Paris Cité #Université Paris-Diderot, UMR 698, CHU X. Bichat, Paris, France.
authors.forename: Ariane
authors.initials: A
authors.lastname: Perry
authors.forename: Hayet
authors.initials: H
authors.lastname: Bensallah
authors.forename: Christine
authors.initials: C
authors.lastname: Martinez-Vinson
authors.forename: Dominique
authors.initials: D
authors.lastname: Berrebi
authors.forename: Brigitte
authors.initials: B
authors.lastname: Arbeille
authors.forename: Julie
authors.initials: J
authors.lastname: Salomon
authors.forename: Olivier
authors.initials: O
authors.lastname: Goulet
authors.forename: Evelyne
authors.initials: E
authors.lastname: Marinier
authors.forename: Séverine
authors.initials: S
authors.lastname: Drunat
authors.forename: Marie-Elisabeth
authors.initials: ME
authors.lastname: Samson-Bouma
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Gérard
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Hugot
mesh_terms: D001284:Atrophy; D001706:Biopsy; D003968:Diarrhea, Infantile / Q000473:pathology* / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008286:Malabsorption Syndromes / Q000150:complications / Q000235:genetics / Q000473:pathology*; D008297:Male; D046529:Microscopy, Electron, Transmission; D008871:Microvilli / Q000235:genetics / Q000473:pathology*; D009081:Mucolipidoses / Q000150:complications / Q000235:genetics / Q000473:pathology*; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics; D024701:Myosin Type V / Q000235:genetics; D010288:Parenteral Nutrition
chemical_list: C505832:MYO5B protein, human; D024701:Myosin Type V; D018995:Myosin Heavy Chains