Patterns of Psoriatic Arthritis

Objective: To describe the clinical patterns of arthritis in psoriasis. Study Design: Cross-sectional, observational study. Place and Duration of Study: Combined Military Hospital, Kharian Cantonment, Pakistan, from January to December 2007. Methodology: One hundred consecutive patients with psoriasis reporting to dermatology outpatient department were included. Pregnant ladies (due to X-ray hazard) and rheumatoid factor positive patients were excluded. The demographic profile of patients was recorded. Psoriatic arthritis was diagnosed on the basis of Moll and Wright criteria. Standardized examination of axial and peripheral joints was made. The severity of psoriasis was assessed by PASI score. The presence of a clinical type of psoriatic arthritis, enthesitis, dactylitis, and nail changes were noted. X-ray films of involved joints were taken. A statistical analysis using chi-square test and student's t-test were done where applicable. Results: The mean age of patients was 39.8+/-15.8 years. Seventy one percent were males and 29% were females. Forty six percent of the patients gave a history of joint involvement and fulfilled the Moll and Wright criteria. The mean PASI score in non-arthritic patients was 26.8+/-34.8 and in psoriatic arthritis patients it was 28.4+/-41.2, p=0.08. Thirteen patients (28.2%) had predominantly axial disease, while the rest had predominantly peripheral disease. Single joint involvement (monoarthritis) was the commonest clinical presentation. Nail involvement was seen in 29% of the patients without arthritis while in patients having arthritis, nail involvement was 74% (P=0.001). Conclusion: Joint involvement is common in psoriatic patients. However, the criteria of diagnosis lack consensus.