Global variation and pattern changes in epidemiology of uveitis.

Uveitis, a complex intraocular inflammatory disease results from several etiological entities. Causes of uveitis are known to vary in different populations depending upon the ecological, racial and socioeconomic variations of the population studied. Tropical countries are unique in their climate, prevailing pathogens and in the existing diseases, which further influence the epidemiological and geographical distribution of specific entities. We provide an overview of the pattern of uveitis of 15221 cases in 24 case series reported from several countries over 35 years (1972-2007) and we integrate it with our experience of an additional 8759 cases seen over six years (1996-2001) at a large community-based eye hospital. Uveitis accounted for 0.8% of our hospital-based outpatient visits. The uveitis was idiopathic in 44.6%, the most commonly identified entities in the cohort included leptospiral uveitis (9.7%), tuberculous uveitis (5.6%) and herpetic uveitis (4.9%). The most common uveitis in children below 16 years (616 patients; 7.0% of the total cohort) was pediatric parasitic anterior uveitis, (182 children, 29.5% of the pediatric cohort), whereas the most common uveitis in patients above 60 years (642 patients; 7.3% of the total cohort) was herpetic anterior uveitis, (78 patients, 12.1% of the elderly cohort). Etiologies varied with the age group of the patients. As in other tropical countries, a high prevalence of infectious uveitis was seen in this population.