title: Polymorphism at codon 469 of the intercellular adhesion molecule-1 locus is associated with protection against severe gastrointestinal complications in Henoch-Schönlein purpura.
abstract: OBJECTIVE
  Henoch-Schonlein purpura (HSP) is a small sized vasculitis affecting mainly children. Intercellular adhesion molecule-1 (ICAM-1) gene polymorphisms have recently been implicated in the susceptibility to some vasculitides. To further investigate the clinical implication of ICAM-1 polymorphisms in HSP, we examined their potential association and influence in the development of severe complications in an unselected series of patients with HSP.
  
  
  METHODS
  Fifty-two patients, of which 41 were children, were diagnosed with HSP using classification criteria of Michel, et al at the Hospital Xeral-Calde (Lugo, Spain); 129 ethnically matched controls were included. Patients had at least one year of followup. Patients and controls were genotyped by allelic oligonucleotide techniques for ICAM-I polymorphism at codon 241 and 469.
  
  
  RESULTS
  The frequency distribution of the alleles and genotypes for each ICAM-1 polymorphism did not show significant differences between HSP patients and controls. Also, no differences between patients with or without renal manifestations were found. However, the frequency of the codon 469 K/E genotype was significantly decreased in patients without severe gastrointestinal manifestations compared to those with them (22.29 vs 65%, OR 0.1, p = 0.02, after correction for age, sex, and disease duration). None of the 11 adults exhibited the R/G genotype at codon 241 compared with 7 of 41 children (OR 0.0, 95% CI 0.0-2.9, p = 0.14). Patients with the R/G genotype were associated with low incidence of renal manifestations and none developed permanent renal involvement (renal sequelae); however, this finding did not achieve statistical significance.
  
  
  CONCLUSIONS
  ICAM-1 polymorphisms alone are not associated with development of HSP, but patients not carrying the codon 469 K/E genotype are at decreased risk of developing severe gastrointestinal complications. The R/G polymorphism at codon 241 may reduce the risk of renal sequelae in the development of HSP in adulthood.
authors.affiliation: ARC Epidemiology Unit, Manchester University Medical School, UK.
authors.forename: M M
authors.initials: MM
authors.lastname: Amoli
authors.forename: D L
authors.initials: DL
authors.lastname: Mattey
authors.forename: M C
authors.initials: MC
authors.lastname: Calviño
authors.forename: C
authors.initials: C
authors.lastname: Garcia-Porrua
authors.forename: W
authors.initials: W
authors.lastname: Thomson
authors.forename: A H
authors.initials: AH
authors.lastname: Hajeer
authors.forename: W E
authors.initials: WE
authors.lastname: Ollier
authors.forename: M A
authors.initials: MA
authors.lastname: Gonzalez-Gay
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004198:Disease Susceptibility; D005260:Female; D005500:Follow-Up Studies; D006471:Gastrointestinal Hemorrhage / Q000453:epidemiology / Q000209:etiology*; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D011695:IgA Vasculitis / Q000150:complications* / Q000453:epidemiology / Q000235:genetics*; D015994:Incidence; D018799:Intercellular Adhesion Molecule-1 / Q000235:genetics*; D007674:Kidney Diseases / Q000453:epidemiology / Q000209:etiology; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D014657:Vasculitis / Q000235:genetics
chemical_list: D018799:Intercellular Adhesion Molecule-1