Anti-cyclic citrullinated peptide antibodies in lung diseases associated with rheumatoid arthritis

Objective Anti-cyclic citrullinated peptide (anti-CCP) antibodies are highly specific markers for rheumatoid arthritis (RA) and useful for predicting RA development and progression. However, it has not been fully determined whether anti-CCP antibodies are associated with pulmonary diseases in RA patients. In the present study, we aimed to elucidate the relationships between anti-CCP antibodies and pulmonary diseases, particularly interstitial lung disease (ILD) and bronchiolitis. Design and methods Using an enzyme-linked immunosorbent assay, the presence of serum anti-CCP antibodies was examined in 18 RA patients with ILD and bronchiolitis who were diagnosed based on pathologic findings. A further 36 RA subjects without any pulmonary diseases served as a reference population. Results No significant differences were found for the prevalences and levels of anti-CCP antibodies between patients with and without ILD and follicular bronchiolitis. Conclusion Detection of serum anti-CCP antibodies has no association with pulmonary diseases in RA patients