Patients with rheumatoid arthritis and gold-induced pneumonitis express two high-risk major histocompatibility complex patterns.
Gold salt therapy-induced pneumonitis is a rare complication in patients with rheumatoid arthritis (RA). We studied HLA-A, B, C, D/DR, and complement factor B (Bf) and C4 alleles in 17 patients with RA and gold-induced pneumonitis and found that these patients had strikingly homogeneous major histocompatibility complex (MHC) markers. Eight of them (47 percent) had the alleles HLA-A3 B35 Dwl BfF C4A3,2 (BO), which were shown by family studies of some patients to be inherited as an extended MHC-haplotype with an apparent gene duplication in the C4A locus. The other high-risk phenotype, HLA-B40 with a C4 null allele, was found in eight patients (47 percent). All but three of the 17 patients had at least one of the two high-risk markers, the frequency of these combinations being clearly higher than in the two control groups: patients with RA but with no gold-induced side effects and healthy individuals. Our study shows that use of several MHC markers together results in a strong association between the markers and the disease.
D000328:Adult; D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology*; D003181:Complement C4 / Q000276:immunology; D005260:Female; D006052:Gold Sodium Thiomalate / Q000009:adverse effects* / Q000627:therapeutic use; D006680:HLA Antigens / Q000276:immunology*; D015235:HLA-B Antigens; D015797:HLA-B35 Antigen; D059947:HLA-B40 Antigen; D006650:Histocompatibility Testing; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011658:Pulmonary Fibrosis / Q000139:chemically induced* / Q000276:immunology; D012306:Risk
D003181:Complement C4; D006680:HLA Antigens; D015235:HLA-B Antigens; D015797:HLA-B35 Antigen; D059947:HLA-B40 Antigen; C048259:HLA-Bf antigen; D006052:Gold Sodium Thiomalate