Tuberculosis is one of the oldest diseases known to humankind and it is currently a worldwide threat with 8-9 million new active disease being reported every year. Among patients with
co-infection of the human immunodeficiency virus (HIV),
tuberculosis is ultimately responsible for the most deaths.
Cutaneous tuberculosis (CTB) is uncommon, comprising 1-1.5% of all
extra-pulmonary tuberculosis manifestations, which manifests only in 8.4-13.7% of all
tuberculosis cases. A more accurate classification of CTB includes inoculation
tuberculosis,
tuberculosis from an endogenous source and haematogenous
tuberculosis. There is furthermore a definite distinction between true CTB caused by Mycobacterium tuberculosis and CTB caused by atypical mycobacterium species. The lesions caused by mycobacterium species vary from small papules (e.g. primary inoculation
tuberculosis) and warty lesions (e.g.
tuberculosis verrucosa cutis) to massive
ulcers (e.g.
Buruli ulcer) and plaques (e.g.
lupus vulgaris) that can be highly deformative. Treatment options for CTB are currently limited to conventional oral
therapy and occasional surgical intervention in cases that require it. True CTB is treated with a combination of
rifampicin,
ethambutol,
pyrazinamide,
isoniazid and
streptomycin that is tailored to individual needs.
Atypical mycobacterium infections are mostly resistant to anti-tuberculous drugs and only respond to certain
antibiotics. As in the case of pulmonary TB, various and relatively wide-ranging treatment regimens are available, although patient compliance is poor. The development of multi-
drug and extremely
drug-resistant strains has also threatened treatment outcomes. To date, no topical
therapy for CTB has been identified and although conventional
therapy has mostly shown positive results, there is a lack of other treatment regimens.