Diagnosis Diagnosis

Leprosy is an important global health concern. Contrary to popular folklore, it is NOT highly contagious, and very effective treatment is available However, early diagnosis and treatment are necessary to minimize the likelihood of disability involving the eyes, hands and feet due to neuropathy as these are often not reversible

Clinical Evaluation

(as the first step in the y)

WHO experts list 3 main diagnostic criteria: 1 2 3

Hypo-pigmented or erythematous skin lesions with loss of sensation

An enlarged peripheral nerve with loss of sensation and/or weakness of muscle supplied by the nerve

A positive acid-fast skin smear or bacilli observed in a smear/biopsy.

The preferred slits for sample collection are active lesions or lesions with altered sensitivity

A negative result does not rule out a clinical diagnosis of Leprosy.

Skin Biopsy and Histopathological Examination

Slit Skin Smear Test

A biopsy is obtained from the leading margin of an active lesion.

It is an intradermal injection of the lepromin antigen (inactivated M. leprae extracted from lepromas) into the flexor surface of the forearm.

The delayed-type hypersensitivity reaction is read at two-time points

It has poor accuracy in diagnosing Leprosy in children and lacks adequate sensitivity and specificity but is still useful for confirming classification and prognosis.

PCR Test

Lepromin Test

They are usually used to support the clinical diagnosis of Leprosy.

Phenolic glycolipid (PLG-1) is the most frequently studied antigen

This test is usually used to monitor the effectiveness of therapy.