Use of antikeratin antibodies to distinguish between rheumatoid arthritis and polyarthritis associated with hepatitis C infection

J Rheumatol. 2000 Mar;27(3):610-2.


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.

Conclusion: AKA is a useful marker to differentiate patients with RA from those with hepatitis C arthritis.

MeSH terms

  • Adult
  • Aged
  • Antibodies / analysis*
  • Arthritis / complications*
  • Arthritis / diagnosis*
  • Arthritis / immunology
  • Arthritis, Rheumatoid / diagnosis*
  • Arthritis, Rheumatoid / immunology
  • Autoimmune Diseases / diagnosis
  • Autoimmune Diseases / immunology
  • Diagnosis, Differential
  • Female
  • Hepatitis C / complications*
  • Humans
  • Immunologic Tests
  • Keratins / immunology*
  • Male
  • Middle Aged


  • Antibodies
  • Keratins