2. Leprosy is caused by Mycobacterium leprae which produces
characteristic lesions in the
skin and the peripheral nerves. M. leprae is an obligate intracellular
acid fast bacilli and
their ability to survive within the macrophages and Schwann cells is a
key feature of their pathogenicity.
Types of leprosy: Clinically, there are four main types of leprosy:
• Lepromatous (LL).
• Tuberculoid (TL).
• Indeterminate (IL); and
• Dimorphic (borderline, BL).
They are determined by the degree of CMI (Cell mediated immunity)
in the host against the lepra bacilli.