Histoid leprosy is a skin condition, a rare form of multibacillary

leprosy Leprosy, also known as Hansen's disease (HD), is a long-term infection by the bacteria ''Mycobacterium leprae'' or ''Mycobacterium lepromatosis''. Infection can lead to damage of the nerves, respiratory tract, skin, and eyes. This nerve damag ...

. It can occur in those with relapsing leprosy after undergoing antibiotic therapy with

dapsone Dapsone, also known as 4,4'-sulfonyldianiline (SDA) or diaminodiphenyl sulfone (DDS), is an antibiotic commonly used in combination with rifampicin and clofazimine for the treatment of leprosy. It is a second-line medication for the treatment a ...

, or less frequently in the first infection (termed ''de novo''). Leprosy can appear in two forms,

tuberculoid leprosy Tuberculoid leprosy is a form of leprosy characterized by solitary skin lesions that are asymmetrically distributed with few lesions and well demarcated edges. There is also early and marked nerve damage. It tends to heal spontaneously. Tuberculoid ...

and

lepromatous leprosy Lepromatous leprosy is a form of leprosy characterized by pale macules in the skin. It results from the failure of Th1 cell activation which is necessary to eradicate the mycobacteria (Th1 response is required to activate macrophages that engulf ...

, and histoid leprosy is a variant of lepromatous leprosy. It appears as "cutaneous and/or subcutaneous

nodules Nodule may refer to: *Nodule (geology), a small rock or mineral cluster *Manganese nodule, a metallic concretion found on the seafloor *Nodule (medicine), a small aggregation of cells *Root nodule Root nodules are found on the roots of plants, p ...

and papules, which are painless, succulent, discrete, smooth, globular, skin-colored to yellowish-brown, with apparently normal skin surrounding it." In India, histoid leprosy is estimated to compose 2.79%-3.6% of all leprosy cases. The male to female ratio in most parts of the world is 2:1. It is treated with antimycobacterial chemotherapy and multibacillary multidrug therapy.

References

Bacterium-related cutaneous conditions {{Cutaneous-infection-stub

See also

References