LTBI initiation: It’s time to be more lenient

S4A - Tuberculosis
LTBI INITIATION: IT’S TIME TO BE MORE LENIENT

Muhammad Khairul Taufiq Rosli
Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia

The “End TB Strategy” of the World Health Organization (WHO) seeks to reduce TB incidence to fewer than 10 cases per 105 people per year by 2035. The primary approach for achieving this goal is to improve efforts to find and treat people with active TB disease, conduct universal screening of individuals at high risk, and provide preventive therapy for those at risk of progressing to active TB disease. A longstanding tenet of TB pathogenesis has been that M. tuberculosis exists (MTB) in either a metabolically inactive latent state or a metabolically active disease state. In this framework, about 5% of people infected with TB progress rapidly to active disease, while the vast majority of people develop a latent infection and remain at risk for progression to active disease. Individuals with LTBI represent a major reservoir for new active TB cases. In recent years, the concept of the tuberculosis (TB) disease spectrum has emerged, recognising that TB exists along a continuum ranging from latent infection through incipient and subclinical disease to active TB disease. Depending on immune status, genetic factors and the presence of comorbidities, individuals can progress or regress along this spectrum . After exposure to Mycobacterium tuberculosis, some individuals may present with TB infection in a quiescent state that is asymptomatic and noncontagious and can be detected using tuberculin skin tests or interferon-gamma release assays (IGRAs). Preventive treatment can be given to eliminate the bacteria and prevent the progression to active TB disease. At the other end of the spectrum, TB disease is characterised by symptoms such as cough, fever, weight loss and night sweats. TB disease diagnosis can usually be confirmed using sputum smear microscopy, mycobacterial culture or molecular tests. Untreated TB disease can be lethal and is a leading cause of morbidity and mortality worldwide