Frequency of iridocyclitis in patients with early psoriatic arthritis: a prospective, follow up study

Objective The occurrence of iridocyclitis (IC) in early psoriatic arthritis (PsA) has been rarely assessed. The primary end-point of this study was to evaluate the frequency of IC at onset in patients with early PsA. Methods We evaluated the frequency of IC in a clinical series of consecutive, new outpatients with early PsA observed between January 2000 and December 2009. All patients met the Classification Criteria for Psoriatic Arthritis (CASPAR) criteria for PsA and had a disease duration ≤12 months. The following clinical patterns were considered: peripheral PsA (oligoarthritis ≤4 and polyarthritis ≥5 involved joints), axial PsA and mixed. IC diagnosis was made by the ophthalmologist. Follow-up visits were scheduled at baseline and every 4 months with interval shortening in the case of urgent clinical problems. Results Two hundred and forty-two patients, 137 (57%) women and 105 (43%) men (mean age 50.33 ± 11.7 years; mean symptom duration 9.38 ± 3.1 months) were studied. One hundred and thirty-two (51%) patients had peripheral PsA, 41 (17%) axial and 69 (28%) mixed. Twenty-six episodes of IC were recorded at diagnosis in 22 (9%) patients, 17 (77.3%) female and five (22.7%) male; 11 (50%) patients had peripheral PsA, two (9.1%) axial, and nine (40.9%) mixed; 5/22 (22.7%) patients were B27-positive. IC recurred in 2/22 (9%) patients over the follow-up period. Mean follow-up duration was 51 ± 23.2 months. Dactylitis was significantly more frequent in patients with IC compared to those without this feature (P = 0.032). Conclusion IC occurred in 9% of 242 patients with early PsA with no association with the clinical pattern and B27 positivity. This frequency is higher than previously reported.