The relation of anti-CCP positivity to HLA-DRB1 alleles and clinical state in rheumatoid arthritis patients

60 RA patients and 60 healthy volunteers were enrolled in the study to search the relation of anti-CCP positivity to shared epitope (SE) by HLA-DRB1 alleles and clinical state in rheumatoid arthritis patients in our society and to compare frequency of anti-CCP in healthy patients and RA patients.Patients enrolled in this study were heterogeneous with regard to age, duration of disease, age at diagnosis and received treatments. Patients? duration of disease, VAS pain, morning stiffness, swollen and tender joints were evaluated. Physical function of the patients was studied using HAQ. DAS-28 scores were calculated by transferring VAS pain, CRP and swollen and tender joint values to a special software program. Anteroposterior radiographs of both hands were obtained, and Larsen scores were determined by a radiology physician using Larsen-Dale method. ESH, CRP, RF, HLA-DRB1 typing and shared epitope were detected on the blood samples of the patients. In RA patients and in healthy volunteers, anti-CCP levels were measured using 2nd generation assay.Although anti-CCP was frequently observed in RA patients, none of the healthy individuals were found to have anti-CCP positivity. Sensitivity and specificity of anti-CCP were 73,3% and 100% respectively for RA. In 50% of RA patients, SE was positive. The most frequently observed HLA gene was HLA-DR4 for SE positive patients (60%) and 30% of these had 2 copies of SE allele.We found that presence of shared epitope increased anti-CCP positivity (TRR=4,33, 95% [95]) and its titre. Anti-CCP positivity had a significant relation with RF positivity. In 86,7% of RA patients, at least one of the autoantibodies was positive. Thus, it was concluded that using both antibodies in clinical practice may increase diagnostic potential.We found that presence of SE causes a significant increase in HAQ score and statistically insignificant increase in average Larsen score. HAQ score had a clear and significant relation to disease activity parameters and Larsen score. Anti-CCP positivity had no significant relation to disease activity and Larsen score.We concluded that longitudinal studies on patient groups having relative homogeneous disease durations would be of useful to determine the relation of these markers to disease activity, joint erosion and severity of disease.