leprosy

· discovered by Hansen in 1873

· chronic infection of skin and peripheral nerves

· granulomatous disease

· due to Mycobacterium leprae

epidemiology

· endemic in some tropical regions

· commonest cause of peripheral neuropathy worldwide

Microbiology

· acid-fast bacilli

· unable to be grown on artificial media

pathology

· Virchow cells

· vacuolated macrophages

clinical findings

· insidious onset

· involves

· skin

· superficial nerves

· nose, pharynx and larynx

· eyes

· testicles

· skin lesions are

· pale anaesthetic macular lesions 1-10 cm dia

· diffuse erythematous infiltrated nodules 1-5 cm dia

· diffuse skin infiltration

· neurological disturbances are

· nerve infiltration and thickening

· other

· leonine facies

· resultant

· anaesthesia and parasthesiae

· trophic ulcers and bone absorption

· shortening of digits

· two forms described

1. lepromatous type

· progressive malignant course

· characterised by severely impaired cell-mediated immunity

2. tuberculoid type

· nonprogressive benign course

· characterised by vigorous cell-mediated response

diagnosis

· bacilli seen in scrapings from skin or nasal mucosa

· culture negative

treatment

· sulphone and rifampicin