EXAMINATION OF HLA-DR4 AS A SEVERITY MARKER FOR RHEUMATOID-ARTHRITIS IN GREEK PATIENTS

Objectives-Previous reports have shown that HLA-DR4 may be a severity marker for rheumatoid arthritis (RA) in patients of northern European origin. The aim of the present study was to investigate this relation in Greek patients with RA, as RA in Greece differs from the RA describ ed previously on clinical, serological, and immunological grounds. Met hods-Eighty four patients were studied in whom HLA-DR typing was perfo rmed by restriction fragment length polymorphism and the subtypes of H LA-DR4 were determined by the polymerase chain reaction. The absence o r presence of HLA-DR4 and its subtypes was correlated with the clinica l and serological characteristics of the patients and with the side ef fects due to disease modifying drugs.Results-Twenty one of the 84 (25% ) patients with RA were DR4+. There was no difference between the DR4 and DR4-patients with respect to duration of disease, severity of art hritis, functional grade, and joint erosion score. The DR4+ group were more likely to have side effects due to disease modifying drugs (43%) than DR4- patients (36%), but this difference was not statistically s ignificant. DR4-patients had more extra-articular manifestations, incl uding Sjogren's syndrome (47 v 19%). Analysis of the DR4 subtypes show ed that Dw15 was the most common variant (9/21 patients; 43%). There w as no statistical difference in the clinical manifestations among pati ents with different DR4 subtypes. The same was also true when the clin ical picture was correlated with the 'shared RA epitope' (QKRAA/QRRAA/ RRRAA), which is common to all HLA-DRB1 alleles positively associated with RA. Conclusions-These results suggest that HLA-DR4 is not a sever ity marker in Greek patients with RA and further indicate differences in the clinical expression of RA in Greece.