Background: Psoriatic arthritis is defined as an inflammatory arthritis associated with psoriasis and is classified as a seronegative HLA-B27-associated spondyloarthropathy. We aimed to study the clinical and paraclinical presentations of psoriatic arthritis in 150 Iranian patients.
Methods: Demographic, clinical, and paraclinical data obtained from 150 patients enrolled in a retro- and introspective study were analyzed.
Results: The female:male ratio was 1.11:1. The mean age at the onset of arthritis was 33.3 years. Arthritis occurred after psoriasis in 73%, preceded it in 17%, and simultaneously in 10% of the patients. The patterns of joint involvement were asymmetric oligoarthritis (46%), polyarthritis (5%), axial involvement (16%), distal interphalangeal joint involvement (23%), and mutilating arthritis (2.2%). There was no correlation between distal interphalangeal joint involvement and nail disease (P=0.33). Polyarthritis was more common in women (P=0.03) and axial involvement was more in men (P=0.02). Patients with spondylitis were younger at the disease onset (P<0.02). Dactylitis was seen in 12% of the patients. Enthesopathy (20.7%) was more common in patients with axial involvement (P=0.008) and joint deformity (15%) was more common in patients with polyarthritis or distal interphalangeal joint involvement (P<0.0002). Four patients had ocular inflammation. Anemia was detected in 24%, high erythrocyte sedimentation rate in 79%, and abnormal urinary indices in 9% of the patients. There was a significant correlation between HLA-B27 (16%) and axial involvement (P=0.01) as well as joint erosions (16%) and distal interphalangeal joint involvement (P<0.0001). Thirty-four patients (26.8%) showed radiographic findings of sacroiliitis, while only 14 of them had axial involvement.
Conclusion: Oligoarthritis was the most common type of joint involvement in these Iranian patients. We found no correlation between distal interphalangeal joint involvement and nail changes, although it was seen with more erosive changes and joint deformity. In comparison with other studies, extra-articular manifestations were not common in our patients.