clinical features

Last reviewed 11/2023

The patient's immune response influences the incubation period and the course of the disease. An effective immune response causes the disease to be tuberculoid with granulomata containing epitheloid cells and lymphocytes, but few or no demonstratible bacilli. An ineffective immune response will lead to lepromatous disease with a histological picture dominated by histiocytes (epithelioid cells) full of bacilli, but few lymphocytes.

The tuberculoid and the lepromatous forms of the disease represent the two poles of the disease. Patients who develop forms that are intermediate between these two forms are described as borderline.

The disease is characterised by cutaneous hypopigmented macules, papules or annular lesions associated with loss of sensation, especially to touch or temperature, and nerve lesions. Damage to larger nerves can cause glove-and- stocking type anaesthesia, with traumatic ulcers in painless areas. The onset is generally insidious.