Use of antikeratin antibodies to distinguish between rheumatoid arthritis and polyarthritis associated with hepatitis C infection.
OBJECTIVE
To investigate whether antikeratin antibodies (AKA) could be useful in the differential diagnosis of patients with rheumatoid arthritis (RA) compared to patients with hepatitis C virus (HCV) associated polyarthritis, who are seropositive for rheumatoid factor (RF).


METHODS
AKA were assayed in 3 different groups of patients; all were RF seropositive: Group 1: 25 patients with HCV associated polyarthralgia or arthritis. Group 2: 33 patients with RA. Group 3: 13 patients with autoimmune disorders other than RA. Fifteen healthy individuals served as controls.


RESULTS
AKA were detected in 20/33 patients with RA (60.6%) compared to only 2/25 patients (8%) with HCV associated arthritis (p < 0.0001). AKA were observed in 2/13 patients of Group 3 (15.3%). These results were also statistically different from those of patients with RA (p = 0.008). AKA were not found in the sera of the healthy controls.


CONCLUSIONS
AKA is a useful marker to differentiate patients with RA from those with hepatitis C arthritis.
Kessel
A
A
Division of Clinical Immunology and Allergy, Bnai Zion Medical Center and Faculty of Medicine, Technion, Haifa, Israel.
Rosner
I
I
Zuckerman
E
E
Golan
T D
TD
Toubi
E
E
D000328:Adult; D000368:Aged; D000906:Antibodies / Q000032:analysis*; D001168:Arthritis / Q000150:complications* / Q000175:diagnosis* / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000276:immunology; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000276:immunology; D003937:Diagnosis, Differential; D005260:Female; D006526:Hepatitis C / Q000150:complications*; D006801:Humans; D007159:Immunologic Tests; D007633:Keratins / Q000276:immunology*; D008297:Male; D008875:Middle Aged
D000906:Antibodies; D007633:Keratins