Posterior Scleritis: Analysis of Epidemiology, Clinical Factors, and Risk of Recurrence in a Cohort of 114 Patients

PURPOSE: To describe the clinical and epidemiological characteristics of patients with posterior scleritis, and to analyze the response to treatment and time to relapse. METHODS: Retrospective study of 114 cases of posterior scleritis from two tertiary care, university-affiliated, referral centers in the United Kingdom and India between 2004 and 2013. Data included sociodemographic factors, medical history, clinical, laboratory and ultrasound findings, therapies, and outcomes. LogMAR visual acuity at presentation and final visit and time to relapse were the main outcome measures. RESULTS: The mean age was 45.9 ± 16.8 years, 71.1% were women, and 18 (15.8%) patients had bilateral disease; 71 (62.3%) cases were idiopathic. Rheumatoid polyarthritis (12.28%), systemic lupus erythematous (4.38%) and pANCA(+) systemic vasculitis (5.26%) were the most frequent systemic associations. VA improved by 0.24 ± 0.36 LogMAR between presentation and last follow up (p < 0.001). The median time to remission was 210 days (95% CI: 184-256 days). Recurrences after remission were observed in 36.63%. The observed incidence rate of posterior scleritis relapse after remission was 15.81% per person-year (95% CI: 11.78-20.77%). Systemic disease was present significantly in patients more than 50 years of age (OR = 2.29; 95% CI: 1.01-5.17; p = 0.044). CONCLUSION: Posterior scleritis is an uncommon disease causing pain and visual loss. In around 40% of the cases, it can be associated with other systemic diseases. Median time to relapse was 210 days. Relapses may occur in around 1 in 3 patients, with an incidence rate of 15.81% per person/year.