SAFA test as an aid to the diagnosis of ocular tuberculosis

A prospective double blind study was carried out to evaluate the role of soluble antigen fluorescent antibody (SAFA) test to detect ocular Tuberculosis. The study material comprised 39 patients with suspected ocular tuberculosis suffering from interstitial keratitis, sclero keratitis, granulomatous uveitis, phlyctenular keratoconjunctivitis, Eales disease and central serous retinopathy. The cases of proven ocular tuberculosis showed up as 70 percent strong reactors and 30 percent weak reactors to SAFA while none had a negative response to SAFA. Of these cases skin hypersensitivity reaction was positive only in 40 percent of the cases. The control group revealed a strong SAFA reaction in only 4 percent of cases with a weak reaction in 44 percent of cases. It thus appears that SAFA test can provide a useful addition to the routine tests in diagnosing tuberculosis.