title: MHC class I and class II genes in Tunisian patients with reactive and undifferentiated arthritis.
abstract: OBJECTIVE
  To study HLA class I and class II association in Tunisian patients with reactive (ReA) and undifferentiated arthritis (UA).
  
  
  METHODS
  The study included 17 patients with ReA defined according to the European Spondylarthropathy Study Group criteria for spondylarthropathy (SpA), 11 patients classified as having undifferentiated arthritis and 100 unrelated healthy controls. HLA class I antigens were typed serologically and HLA class II alleles were genotyped molecularly by the polymerase chain reaction with sequence-specific primers technique.
  
  
  RESULTS
  There was a major difference between HLA alleles in ReA and UA patients when compared separately with controls. Increased frequencies of HLA-B27 (p=7.76 10-12, OR=59.30), HLA-B51 (p=0.015, OR=4.91) and HLA-DRB1*04 (p=0.033, OR=2.90) alleles were found in patients with ReA but not in patients with UA. HLA-B27 was not expressed totally in our cohort of UA patients. A significant increase of HLA-B15 (p=0.002, OR=18.40) and a moderate increase of HLA-B7 (p=0.043, OR=5.15) was found in patients with UA, but not in patients with ReA. In the B27 negative patients, HLA-DRB1*04 association with ReA was found independently of B27.
  
  
  CONCLUSIONS
  Our data confirmed a significant association of HLA-B27 with ReA in the Tunisian population. Our results also suggested that some of the additional HLA antigens were associated with ReA including HLA-B51 and HLA-DRB1*04 alleles. UA seemed to have a genetic background different from ReA in Tunisian patients.
authors.affiliation: Laboratoire de recherche "Micro-organismes et Pathologie Humaine", EPS Habib Bourguiba de Sfax, Tunisia.
authors.forename: M
authors.initials: M
authors.lastname: Siala
authors.forename: N
authors.initials: N
authors.lastname: Mahfoudh
authors.forename: H
authors.initials: H
authors.lastname: Fourati
authors.forename: R
authors.initials: R
authors.lastname: Gdoura
authors.forename: M
authors.initials: M
authors.lastname: Younes
authors.forename: A
authors.initials: A
authors.lastname: Kammoun
authors.forename: I
authors.initials: I
authors.lastname: Chour
authors.forename: N
authors.initials: N
authors.lastname: Meddeb
authors.forename: L
authors.initials: L
authors.lastname: Gaddour
authors.forename: F
authors.initials: F
authors.lastname: Hakim
authors.forename: S
authors.initials: S
authors.lastname: Baklouti
authors.forename: N
authors.initials: N
authors.lastname: Bargaoui
authors.forename: S
authors.initials: S
authors.lastname: Sellami
authors.forename: A
authors.initials: A
authors.lastname: Hammami
authors.forename: H
authors.initials: H
authors.lastname: Makni
mesh_terms: D000328:Adult; D001168:Arthritis / Q000235:genetics*; D016918:Arthritis, Reactive / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D005805:Genes, MHC Class I / Q000235:genetics*; D005802:Genes, MHC Class II / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D015235:HLA-B Antigens / Q000235:genetics; D059910:HLA-B15 Antigen; D015796:HLA-B27 Antigen / Q000235:genetics; D059949:HLA-B51 Antigen; D015793:HLA-B7 Antigen / Q000235:genetics; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006801:Humans; D008297:Male; D008875:Middle Aged; D000091402:Prohibitins; D014416:Tunisia; D055815:Young Adult
chemical_list: D015235:HLA-B Antigens; D059910:HLA-B15 Antigen; D015796:HLA-B27 Antigen; D059949:HLA-B51 Antigen; D015793:HLA-B7 Antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C527195:HLA-DRB1*04 antigen; C000717331:PHB2 protein, human; D000091402:Prohibitins