Absence of antibodies to cyclic citrullinated peptide in sera of patients with hepatitis C virus infection and cryoglobulinemia

✍ Scribed by Mark H. Wener; Kathleen Hutchinson; Chihiro Morishima; David R. Gretch

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 61 KB
• Volume: 50
• Category: Article
• ISSN: 0004-3591
• DOI: 10.1002/art.20355

✦ Synopsis

Abstract

Objective

To determine if antibodies to cyclic citrullinated peptide (anti‐CCP) are found in chronic hepatitis C virus (HCV) infection.

Methods

Rheumatoid factor (RF) and anti‐CCP were measured in sera from 50 patients with HCV infection but without cryoglobulinemia, sera from 29 patients with mixed cryoglobulinemia (including 13 with rheumatic symptoms and 5 with arthritis), and sera from 20 normal blood donors. Anti‐CCP was measured by second‐generation enzyme‐linked immunosorbent assay (ELISA).

Results

No sera with elevated anti‐CCP were found in patients with HCV infection without cryoglobulinemia, and in that population, the maximum anti‐CCP was 10 units, well below the positive cutoff of 20 units. Positive findings on RF testing >13 IU/ml were present in 22 (44%) of the HCV patients, with RF >50 IU/ml in 8 (16%) and a maximum RF of 526 IU/ml. Of the cryoglobulinemia patients, 22 (76%) had positive results on tests for RF, including 18 (62%) with RF >50 IU/ml and a maximum RF of 5,540 IU/ml. Two (6.9%) of the cryoglobulinemia patients had borderline‐positive findings on tests for anti‐CCP (25 units and 37 units), which were false‐positive results caused by nonspecific binding in the ELISA. No association between the RF and the anti‐CCP concentrations was found.

Conclusion

Whereas RF was frequent in patients with HCV infection with and without cryoglobulinemia, anti‐CCP was not observed in patients with uncomplicated HCV infection. Borderline‐positive anti‐CCP results were observed infrequently in patients with mixed cryoglobulinemia and were caused by nonspecific binding to plastic. Measurement of anti‐CCP may help in diagnosing RA in patients with chronic HCV infection.