Leprosy (Hansen's disease)

For a lay person:

Leprosy, or Hansen's disease, is a long-term bacterial infection of the skin and nerves. It spreads only with prolonged close contact, is curable with antibiotics, and early treatment prevents the nerve damage that causes disability.

For a trained medical person:

Caused by Mycobacterium leprae (and M. lepromatosis), with a spectrum from tuberculoid to lepromatous disease depending on host immunity; immune reactions (type 1 reversal and erythema nodosum leprosum) can cause acute nerve damage. Diagnosis is clinical, with anaesthetic skin lesions and enlarged peripheral nerves, supported by slit-skin smears and biopsy. Treatment is WHO multidrug therapy with rifampicin, dapsone and clofazimine, plus corticosteroids for reactions and care to protect insensate limbs and eyes.

In Chinese medicine:

Liu and Tseng's textbook differentiates this condition into these patterns: Blood-Heat, Blood Stasis; Damp-Heat Obstruction; Yin Deficiency and Blood Heat; Liver Qi Stagnation and Blood Stasis; Qi and Blood Deficiency; Qi Stagnation and Blood Stasis. Treatment follows the pattern a patient presents with, not the Western diagnosis alone.

When to get help: Leprosy needs multidrug antibiotic treatment through a medical or public-health programme, and Chinese medicine is adjunctive at most; it is notifiable in many countries. Get prompt care for new numbness, weakness, painful nerves or red eyes.