pcr in the diagnosis of intraocular tuberculosis; a report of 13 cases

purpose: to evaluate the diagnosis of intraocular tuberculosis (tb) with polymerase chain reaction (pcr) and to report 13 cases of presumed intraocular tb. methods: of 168 patients with uveitis, 13 patients (7.74%) had criteria for intraocular tb (tb group). thirteen patients with non-tb uveitis were randomly selected as the control group. samples for pcr were obtained from the aqueous humor. systemic evaluations, tuberculin skin test, and aqueous pcr were performed in all patients. the clinical and paraclinical findings and the treatment of patients with presumed intraocular tb were evaluated. results: mean age of the tb group was 42.6±14y, 9 patients were female and 4 were male. mean age of the control group was 37.15±15.32, 7 patients were male and 6 were female. tuberculin skin test was positive in 11 patients of the tb group vs 2 patients in the control group (p=0.001). three patients in the tb group (23%) and none of the control group had positive pcr test. posterior segment findings in the tb group included multifocal choroiditis in 4 patients (30.77%), single choroidal nodule (tuberculoma) in 1, retinal perivasculitis in 1, macular edema in 1, and intermediate uveitis in 1. in 5 other patients, no findings were observed in the posterior segment. coexistant lung or other organ disease was found only in one patient and positive family history for tb was found in another. conclusion: use of the tuberculin skin test is advisable and if results are above 19 mm of induration, the possibility of intraocular tb is reinforced, but negative tests are not sufficient for exclusion. pcr-positive patients must be treated with complete anti-tb treatment for eradication of bacilli.