Leprosy Training Module for Medical Officers

Diagnosis of Leprosy
A case of Leprosy is diagnosed by eliciting cardinal signs of Leprosy
through systematic clinical / bacterial examination.
Diagnosis of leprosy can be done on the basis of the following cardinal
signs. Presence of any one of the cardinal signs is sufficient to diagnose a
case as a Leprosy case.
1. Hypo pigmented or reddish colour skin patch(es) with
definite loss of sensation
2. Thickness and / or tenderness of peripheral nerves, resulting
into damage to them, demonstrated by loss of sensation and
weakness of muscles of hands, feet or face .
3. Demonstration of acid-fast bacilli in skin smears .
The Skin Lesion can be single or multiple, usually less pigmented than
the surrounding normal skin. Sometimes, the lesion is reddish or copper –
coloured. A variety of skin lesions may be seen but macules ( flat ),
papules ( raised ) or nodules are common. Sensory loss is a typical feature of
PB Leprosy. The skin lesion may show loss of sensation to pin prick and / or
fine touch.
Nerve Damage, mainly to peripheral nerve trunks, constitutes another
feature of Leprosy. There may be loss of sensation in the skin and weakness
of muscles supplied by the particular peripheral nerve affected. In the absence
9