Ocular Tuberculosis: Biomarkers for Risk Stratification

Mycobacterium tuberculosisMycobacterium tuberculosis (M. tb) can occur in organs other than the lungsLung, including the eyeEye, called ocular tuberculosisTuberculosisocular (TB). This infection causes abnormalities of some eyeEye parts, primarily involving the uveaUvea. About 30–50% of uveitis cases in developing countries are caused by infection, including TB. The clinical manifestation of uveitis associated with M. tb can mimicMimic other causes. Since uveitis is a vision-threatening inflammatory disease, an accurate diagnosis is crucial. Ocular fluidsFluid collected for acid-fast smearSmear, culture, or M. tb polymerase, often do not provide evidence of infection because of its low sensitivity and morbidityMorbidity associated with invasive sampleSample collection. It is essential to know the status of latent or active TBTuberculosisactive to guide in giving proper treatment for the right patient. Biomarkers, the parametersParameter that can be used as an objective measure of a normal or pathogenic biological process, can be helpful to overcome the problems. Several candidate biomarkersBiomarkercandidate being studied, especially hostHost-derived biomarkers, have shown promising results in ocular TBTuberculosisocular diagnosis. These include assessment of geneGene expression, microRNAsMicroRNA, proteinProtein analysis, and cellular immunophenotypingImmunophenotyping. These biomarker candidatesCandidate can be developed further to stratify ocular TBTuberculosisocular and overcome the limitation of finding M. tb in ocular tissuesTissue.