Diagnosis of Ocular Tuberculosis: A Role for New Testing Modalities?

Tuberculosis (TB) is a disease caused by the acid-fast bacillus (AFB) Mycobacterium tuberculosis. TB usually affects the lungs [pulmonary TB (PTB)], but it can also affect any other part of the body [extrapulmonary TB (EPTB)]. EPTB with no evidence of pulmonary involvement accounted for 21.1 % of those with TB in 2005, which represents an increase from 16 % in 1992.1 The increase in the proportion of TB cases that are HIV coinfected has contributed to this increase in EPTB.2 The general symptoms of TB include weakness, weight loss, fever, and night sweats. Symptoms of PTB may also include coughing, chest pain, and hemoptysis. Symptoms of EPTB depend on the area affected. TB is spread from person to person through the air when a person with PTB coughs, sneezes, or speaks. Persons who breathe in the air containing M. tuberculosis can become infected asymptomatically; this is called latent TB infection (LTBI). It is estimated that one-third of the