Polymerase chain reaction confirmed mycobacterium tuberculosis intermediate uveitis – analysis of 22 eyes of 14 cases from a tertiary care centre in South India: a retrospective study

BACKGROUND: To report the role of Polymerase Chain Reaction in confirming the diagnosis of presumed Mycobacterium Tuberculosis (MTB) Intermediate Uveitis. METHOD: Retrospective analysis of 22 eyes of 14 cases of presumed tubercular intermediate uveitis wherein intraocular fluid was tested for MTB DNA by Nested & Real-time PCR, based on clinical suspicion of tubercular aetiology. QuantiFERON TB gold test and High-Resolution CT Chest were done. Patients were treated with anti-tubercular therapy with oral steroids & immunomodulators. In the study, eleven were male (79%) and three female (21%). The median age was 34 years. Nested PCR for both IS 6110 & MPB 64 was positive in 64% of the cases, IS 6110 positive in 23% and MPB 64 positive in 15%. Real-time PCR was positive in 48% of the cases. Vision improved in 33% of cases, maintained in 57%, and worsened in 10% of cases. CONCLUSION: Presumed Tubercular intermediate uveitis can be confirmed by PCR of intraocular fluids. Anti-tubercular therapy with immunosuppression can improve vision and prevent recurrences in such cases.