Analysis of human leukocyte antigens in patients with internal derangement of the temporomandibular joint.

PURPOSE: Spondyloarthropathy includes the subcategory of reactive arthritis (ReA). Spondyloarthropathies are commonly associated with certain human leukocyte antigen (HLA) alleles. Because we identified bacteria associated with ReA within the temporomandibular joint (TMJ), we now evaluate the frequency of HLA alleles in patients with TMJ pathology. PATIENTS AND METHODS: HLA typing of 129 patients (121 females and 8 males) performed by standard microcytotoxicity technique. Thirty patients had only class I (HLA-A and -B loci) evaluated. Ninety-nine patients had both class I and class II (HLA-DR loci) evaluated. Identification of alleles at the C locus was not performed. The antigenic frequency in the study group was compared to US white control subjects using a 2-tailed Fisher's exact test with a Bonferroni multiple comparison adjustment. RESULTS: The following class I HLA alleles, -A1 (32%), -A2 (50%), -A3 (33%), -B7 (23%), -B14 (14%), -B35 (20%), and -B44 (36%), including the B7 cross-reactive group (CREG) (49%) and class II alleles -DR1 (25%) and -DR4 (34%), were found to have an increased frequency in our patient group. CONCLUSIONS: Our study shows an increased frequency of several alleles that have been previously associated with arthropathy, and the alleles of the B7 CREG, in patients with TMJ pathology. Patients with these alleles may have an increased risk for the development of internal derangement of the TMJ as a consequence of the bacterial/infectious agents and host interactions with the subsequent cytokine/inflammatory response being influenced by their HLA phenotype.