Leprosy characteristics

Characteristics
The clinical manifestations of leprosy vary but primarily affect the skin, nerves, and mucous membranes. Patients with this chronic infectious disease are classified as having paucibacillary (tuberculoid leprosy), multibacillary Hansen's disease (lepromatous leprosy), or borderline leprosy.

Borderline leprosy (also termed multibacillary), of intermediate severity, is the most common form. Skin lesions resemble tuberculoid leprosy but are more numerous and irregular; large patches may affect a whole limb, and peripheral nerve involvement with weakness and loss of sensation is common. This type is unstable and may become more like lepromatous leprosy or may undergo a reversal reaction, becoming more like the tuberculoid form.

Paucibacillary Hansen's disease is characterized by one or more hypopigmented skin macules and anaesthetic patches, i.e., damaged peripheral nerves that have been attacked by the human host's immune cells.

Multibacillary Hansen's disease is associated with symmetric skin lesions, nodules, plaques, thickened dermis, and frequent involvement of the nasal mucosa resulting in nasal congestion and epistaxis (nose bleeds) but typically detectable nerve damage is late.

Contrary to popular belief, Hansen's bacillus does not cause rotting of the flesh; rather, a long investigation by Paul Brand yielded that insensitivity in the limbs extremities was the reason why unfelt wounds or lesions, however minute, lead to undetected deterioration of the tissues, the lack of pain not triggering an immediate response as in a fully functioning body. Recently, leprosy has also emerged as a problem in HIV patients on antiretroviral drugs.