Uveitis of Unknown Etiology: Clinical and Outcome features. A Retrospective Analysis of 355 Patients.

Purpose: Despite the huge advance in diagnostic technics, about one-third of uveitis is still considered of unknown etiology. In this study, we aimed to report their clinical features and to describe how a diagnosis has been finally reached for some patients.

Methods

We retrospectively reviewed all patients with uveitis referred to our tertiary center between 2002 and 2016. The unknown etiology was admitted after a new ophthalmologic examination and a full work-up in internal medicine in our tertiary center.

Results

Among 957 patients with uveitis, 355 had uveitis of unknown etiology. The clinical and epidemiological characteristics of this subgroup were no different from those with a known etiology. Out of 104 patients who were followed-up for more than 1 year, a diagnosis was finally achieved in 20 patients. The diagnosis was determined either because of the occurrence of a new clinical symptom (n = 10), a new/repeated non-ophthalmologic investigation (n = 7), or a new/repeated ophthalmic exam (n = 3).

Conclusion

A prolonged follow-up, with repeated exams, may allow the determination of an etiology in about one-fifth of uveitis initially considered as idiopathic.