Assessment of anti-cyclic citrullinated peptide in psoriatic arthritis

BACKGROUND: Anti-cyclic citrullinated peptides (anti-CCP) are highly specific diagnostic and prognostic markers for rheumatoid arthritis (RA). They have been also found in psoriatic arthritis (PsA), with controversies as regards clinical and radiological associations. The current study assessed anti-CCP in PsA and determined its clinical and radiological associations. METHODS: Four groups contributed to this study. 40 PsA, 40 psoriasis without arthritis, 40 RA and 40 healthy controls. They were tested for anti-CCP. Clinical and radiological data were collected and statistically compared between anti-CCP-positive and -negative PsA patients. RESULTS: Seven PsA (17.5%) and 34 RA (85%) were seropositive for anti-CCP. Patients of other groups were anti-CCP-negative. Regarding anti-CCP concentrations, highly significant difference existed between different groups and between anti-CCP-positive and -negative PsA. Significantly higher numbers of involved, swollen and tender joints, deformities and functional impairment of peripheral joints and radiological changes were found in anti-CCP-positive PsA. CONCLUSION: Anti-CCP may be found in PsA and are associated with higher number of involved, swollen and tender joints, with deformities and functional impairment of peripheral joints and with erosive arthritis.