Determination of anti-cyclic citrullinated peptide antibodies in the sera of patients with liver diseases.
OBJECTIVE
To determine the frequency of anti-cyclic citrullinated peptide (anti-CCP) antibodies in patients with HCV infection, primary biliary cirrhosis (PBC) and type-I autoimmune hepatitis (AIH) to assess the specificity of anti-CCP antibodies.


METHODS
Rheumatoid factor (RF) and anti-CCP antibodies were measured in the sera from patients with HCV infection (n=45), PBC (n=73), AIH (n=55) and rheumatoid arthritis (n=48), and also from the sera of healthy subjects (n=23). Anti-CCP antibodies were measured using a second generation enzyme-linked immunosorbent assay (ELISA).


RESULTS
No sera with elevated anti-CCP were found in the patients with HCV infection. Two PBC patients (2.7%) and six AIH patients (10.5%) had anti-CCP antibodies. The seropositivity for anti-CCP in these autoimmune disease patients was associated with a high frequency of RA association [PBC; 100% (2/2), AIH; 86.4% (5/6)].


CONCLUSIONS
Although anti-CCP antibodies may be present in patients with autoimmune liver diseases, almost seropositive patients had concomitant RA. As a result, the measurement of anti-CCP antibodies may therefore be helpful for accurately diagnosing RA in patients with these liver diseases.
Koga
T
T
Clinical Research Center and Clinical Laboratory, NHO Nagasaki Medical Center, Omura, Japan.
Migita
K
K
Miyashita
T
T
Maeda
Y
Y
Nakamura
M
M
Abiru
S
S
Myoji
M
M
Komori
A
A
Yano
K
K
Yatsuhashi
H
H
Eguchi
K
K
Ishibashi
H
H
D000918:Antibody Specificity; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D006526:Hepatitis C / Q000276:immunology; D019693:Hepatitis, Autoimmune / Q000276:immunology; D006801:Humans; D008105:Liver Cirrhosis, Biliary / Q000276:immunology; D008107:Liver Diseases / Q000150:complications / Q000276:immunology*; D010456:Peptides, Cyclic / Q000276:immunology*; D012217:Rheumatoid Factor / Q000032:analysis
D001323:Autoantibodies; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor