Information on the Test Items

Interferon-gamma releasing assay (IGRA)

Latent tuberculosis infection (LTBI) refers to a condition where an individual is infected with the tuberculosis bacterium but remains asymptomatic, with no outward signs of tuberculosis and no risk of transmitting the infection to others. It affects approximately 30% of close contacts of tuberculosis patients. Among those infected, approximately 10% progress to active tuberculosis disease, with 5% developing active disease within 2 years and the remaining 5% over the course of their lifetime, particularly during periods of significant immunosuppression.​