Mycobacterial Tuberculosis Epidemiology and Pathogenesis

Mycobacterium tuberculosis (MTB) is an acid fast bacterium (AFB); it has tough cell wall and circular chromosome. It is transmitted through the airborne route and cause tuberculosis (TB). The distribution of tuberculosis is not uniform across the globe; about 80% of the population in many Asian and African countries and it is the second most common cause of death from infectious disease after HIV. Organisms deposited mainly in the upper lung zones, kidneys and bones. In persons with intact cell-mediated immunity (CMI), collections of activated T cells and macrophages form granulomas that limit multiplication and spread of the organism. The Status of CMI will determine if the patient will get active or latent TB infection.