Background: We evaluated the significance of the genes, defined as DRB1*04 or DRB1*01, in
rheumatoid arthritis (RA) patients. We focused on the role of genetic and serologic markers to
predict disease activity and destructive process of joints.
Methods: Sixty patients with RA were examined. Radiographic changes were evaluated by (Larsen
score) and disease activity was measured by disease activity score 28 (DAS28). The markers
analyzed were: erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor
(RF), anti-cyclic citrullinated peptides (anti-CCP2) and HLA-DRB1 alleles typed by PCR.
Results: In this study, anti-CCP antibodies, CRP, RF and AKA were detected in 83.3%, 56.7%,
71.7% and 52% of patients respectively. HLA-DRB1*01 was found in 45% of patients and 35% of
them had one or two HLA-DRB1*04 alleles. According to DRB1*04 subtypes, (DRB1* 0405) was
present in of 80% them. For prediction of grade of activity, the independent predictors were anti-
CCP (OR 19.6), and DRB1*04 positive allele (OR 5.1). The combination of DRB1*04 + anti-CCP
antibodies gave increase in the specificity and positive predictive value to 92% and 90 respectively.
As regards to the prediction of radiological joint damage, the independent predictors were HLADRB1*
04, HLA-DRB1*01, RF, and CRP > 18 (OR 5.5, 4.5, 2.5, 2.0 respectively).
Conclusion: Our findings suggest that anti-CCP2 is superior to RF for the detection of RA and
provided predictive information on joint destruction and disease activity. The presence of RA
associated antibodies (ACCP or RF) and/or the SE genes are indicative for a poorer radiological
outcome and higher grade of activity.