Cutaneous leishmaniasis with histopathologic pattern of non-necrotizing granulomatous dermatitis in patients treated with adalimumab.

Human leishmaniasis produced by Leishmania infantum is endemic in Mediterranean countries. In the context of a leishmaniasis outbreak in the town of Fuenlabrada, Madrid, Spain, we had two patients with cutaneous leishmaniasis that developed non-necrotizing cutaneous granulomas. They had both been receiving anti-TNF treatment with adalimumab for rheumatic diseases. Neither of them developed visceral disease and did not require anti-TNF treatment withdrawal to control the cutaneous disease. It is well known that anti-TNF therapy is associated with opportunistic diseases, especially with those in which granuloma formation is an important part of the host defence, as in tuberculosis. We think that granuloma formation through activation of Toll-like receptor-9 and via induction of a Th17 response may be precipitated by the parasites in the dermis.