title: Intestinal disease in Hermansky-Pudlak syndrome: occurrence of colitis and relation to genotype.
abstract: OBJECTIVE
  Hermansky-Pudlak syndrome (HPS), a rare autosomal recessive disorder characterized by oculocutaneous albinism and platelet dysfunction, results from mutations in 1 of at least 7 different genes. Some patients develop a fatal pulmonary fibrosis and others a disabling colitis. This study aimed to document the occurrence of colitis among HPS patients, characterize gastrointestinal tract involvement in HPS, and analyze the distribution of colitis among HPS genotypes.
  
  
  METHODS
  Of the 122 HPS patients followed at the National Institutes of Health Clinical Center between 1993 and 2005, 24 were evaluated by endoscopy for gastrointestinal complaints. The histology of gastrointestinal biopsies was retrospectively examined to assess for inflammatory changes, granulomata, and pigmented macrophages. These data were compared with symptoms and HPS genetic subtypes.
  
  
  RESULTS
  At colonoscopy, 7 of 23 patients (30%) had endoscopic mucosal abnormalities, including nodularity, erythema, petechiae, or erosions. Six of these 7 patients (86%) had findings of colitis on biopsy. Of the 16 patients with normal-appearing colonic mucosa, 2 patients (12%) had colitis on biopsy. Pigmented macrophages were also observed in the colonic lamina propria in 16 of the 23 patients (70%). Of the 8 patients with confirmed colitis, 7 had the HPS-1 subtype, and 1 had the HPS-4 subtype.
  
  
  CONCLUSIONS
  There is an increased frequency of colitis in our population of 122 HPS patients (8/122, 7%) and in HPS patients referred specifically for symptom evaluation (8/24, 33%). Colitis was found in patients with HPS-1 and HPS-4 genotypes.
authors.affiliation: National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-1851, USA.
authors.forename: Nadeem
authors.initials: N
authors.lastname: Hussain
authors.forename: Martha
authors.initials: M
authors.lastname: Quezado
authors.forename: Marjan
authors.initials: M
authors.lastname: Huizing
authors.forename: David
authors.initials: D
authors.lastname: Geho
authors.forename: James G
authors.initials: JG
authors.lastname: White
authors.forename: William
authors.initials: W
authors.lastname: Gahl
authors.forename: Peter
authors.initials: P
authors.lastname: Mannon
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003092:Colitis / Q000235:genetics* / Q000473:pathology; D003113:Colonoscopy; D005260:Female; D005838:Genotype; D022861:Hermanski-Pudlak Syndrome / Q000145:classification / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies