Mycobacterium leprae, Mycobacterium lepraemurium and Non-tuberculosis Mycobacteria

Mycobacterium leprae is the causative agent of leprosy, a chronic granulomatous disease primarily affecting the skin and peripheral nervous system. M. leprae was the first bacterial pathogen associated with a specific human disease and the only mycobacterium known to cause infection of the nervous tissue. The Koch postulates have never been fulfilled for M. leprae because so far, it has not been cultivated in vitro.