ABSTRACT
Objective: To distinguish between rheumatoid arthritis [RA] and polyarthritis associated with hepatitis C virus infection [HCV] using a marker more specific to RA than the rheumatoid factor [RF] such as antikeratin antibody [AKA]
Methodology: Fifty rheumatoid factor [RF] positive patients were selected from those fulfilling the American College of Rheumatology [ACR] revised criteria. They were classified into two groups. Group I: 25 patients who were anti HCV antibodies seropositive. Group II: 25 patients who were anti HCV antibodies seronegative. In addition, 15 healthy individuals acted as controls. Investigations were done for all groups such as: Complete blood count [C.B.C], erythrocyte sedimentation rate [ESRO, C reactive protein [CRP], Antinuclear antibody [ANA] and [AKA]. Plain X- rays of both hands were done for all patients to exclude the patients with bone erosions
Results: Seropositive AKA was found in a high percentage in group [II] 60% whereas it was found in lower percentage in group [I] 12% and not found at all in control group. The specificity and sensitivity of AKA in group I was 91.1%, 60% respectively. Also, we found that the presence of AKA is associated with raised both ESR and CRP
Conclusion: Anti-Keratin Antibodies are a relatively simple means, which may help in discrimination of patients with HCV related arthritis from those with true RA