Etiology of Anterior Uveitis in a Finnish Single-Center Register Study - Differences in Clinical Characteristics, Treatment Outcomes, and Ocular Complications.

Purpose: To evaluate clinical characteristics, treatment outcomes, and complications in anterior uveitis (AU) with idiopathic, systemic disease-associated, infectious, postoperative, and posttraumatic etiology.

Methods: Long-term analysis of a single-center register study from adults with AU in 2009. Etiology, age at onset, sex distribution, course of uveitis, visual outcomes, treatments, and ocular complications were studied during 1998-2018.

Results: A total of 413 patients with AU were included. A total of 195 patients (47%) had idiopathic, 150 (36%) systemic disease-associated, 25 (6%) infectious, 26 (6%) postoperative, and 17 (4%) traumatic AU. Average onset age varied from 38 ± 13 (95% CI, 36.2-40.5) in systemic disease-associated to 59 ± 19 (95% CI, 51.5-66.5) in postoperative AU (p < 0.001). Sex distribution varied between 62% females in postoperative and 29% females in traumatic uveitis. Traumatic AU was predominantly acute (59%), and infectious AU recurrent (44%) or chronic (40%). Idiopathic (58%), systemic disease-associated (65%), and postoperative AU (62%) were commonly chronic (p = 0.036). After the active follow-up, traumatic patients gained +2 ETDRS letters, while vision remained stable in idiopathic (-0.5 letters) and systemic disease-associated (+0.8 letters) AU. Patients with infectious and postoperative AU lost -2 and -10 letters, respectively. Highest frequency of complications occurred in traumatic (50%) and the lowest in postoperative AU (35%). Three patients with idiopathic and two with postoperative AU were blind after the follow-up.

Conclusion: The study underscores significant differences in the onset age, course of uveitis, vision, intraocular pressure, flare, and treatment modalities among the etiological subgroups of AU. However, no substantial differences were observed concerning complications or visual outcomes.