de novo Histoid leprosy: an expatriate case recently diagnosed in Johannesburg.

Histoid leprosy (HL) is a rare variant of lepromatous leprosy with unique clinical, histopathological, and microbiological features. A 32-year-old man from Malawi who immigrated to Johannesburg 1-year-ago, presented with a 4-month history of flesh-colored nodules on the face and trunk and hyperpigmented plaques on the chest and limbs. Skin slit smears confirmed multibacillary leprosy, and skin punch biopsies showed proliferation of spindled cells containing a large number of acid-fast bacilli. The prevalence of de novo HL is increasing in the era of leprosy elimination. HL cases may act as reservoirs and negatively affect the global control of leprosy.