The Importance of QuantiFERON Gold Plus Test for the Diagnosis of Presumed Ocular Tuberculosis

In 2021, the World Health Organization (WHO) estimated 10.6 million new cases of active tuberculosis (TB) [1]. A TB infection results from the inhalation of small droplets contaminated with Mycobacterium tuberculosis (Mtb). Within 4 to 12 weeks after inhalation, a local tissue response and, in some cases, a hematogenous dissemination of Mtb occurs. Although the lung is the primary site of infection and pulmonary TB can be easily diagnosed by chest X-ray, extrapulmonary manifestations are not uncommon. After primary infection, patients may completely clear the Mtb, develop TB disease, or enter a latent stage (latent tuberculosis infection, LTBI) [2]. Reactivation of TB may occur without systemic symptoms and in extrapulmonary localization. In LTBI and in some extrapulmonary reactivations, diagnosis relies on indirect methods that assess the presence of sensitized lymphocytes capable of releasing cytokines when stimulated by mycobacterial antigens [3].