Polymerase Chain Reaction and its Correlation with Clinical Features and Treatment Response in Tubercular Uveitis

Correlation of results of polymerase chain reaction for Mycobacterium tuberculosis (MTB PCR) with clinical features and treatment response in tubercular uveitis.

Retrospective case study.

Among 56 patients, 31 (55.3%) had acute and 25 (44.6%) had chronic uveitis. Uveitis was unilateral in 40 (71.4%) and bilateral in the remaining 16 (28.6%). Anatomical subtypes of uveitis were: anterior in 10 (13.9%) eyes, intermediate in 9 (12.5%), posterior in 17 (23.6%), and pan uveitis in 36 (50%) eyes. MTB PCR was positive in 24 patients. There was an 80% correlation between clinical response to antitubercular therapy (ATT) and PCR results. Twenty-two patients with positive PCR had a good clinical response. The sensitivity and specificity was 73.3% and 92.3%, respectively.

The diagnosis of intraocular TB requires strong clinical suspicion with corroborative laboratory and radiological evidence. A positive PCR is reliable whereas negative results should be correlated with clinical features. An adequate response to ATT supports PCR results.