A forgotten and hidden disease

A 50 year old man presented to a clinic with a two year history of multiple hypopigmented patches spread over the trunk and all four limbs (fig 1⇓). The patches were variable in size with central clearing; some margins were well defined and some poorly. Hair growth over the lesions was sparse, and he had loss of sensation over some of the patches. The peripheral nerves—ulnar, lateral popliteal, and posterior tibial—were thickened, with mild weakness in the muscles they supplied, but there was no loss of sensation in the hands and feet. A slit-skin smear …