Atypical cutaneous leishmaniasis in a patient under tumour necrosis factor alpha inhibitor for psoriasis

Tumor necrosis factor (TNF) inhibitors are associated with a higher risk of infection. Cases of cutaneous leishmaniasis have been rarely reported in this population, mostly with those taking adalimumab and infliximab.A man in his 60s with chronic plaque psoriasis developed a cutaneous lesion on his leg after 2 years of adalimumab therapy. It was initially misdiagnosed and unsuccessfully treated as a bacterial ulcer, but a skin biopsy later confirmed Leishmania donovani complex infection. Adalimumab was discontinued, and the patient was treated with intravenous liposomal amphotericin B, leading to the resolution of the ulcers. His psoriasis worsened post-treatment but was managed with risankizumab, and 2 years later, no evidence of leishmaniasis relapse was noted.This case highlights the importance of vigilance for leishmaniasis in patients taking TNF inhibitors, especially in endemic regions, as diagnosis can be challenging. Although there is no consensus on managing leishmaniasis in this population, treatment often involves discontinuing TNF inhibitors and using systemic antileishmanial drugs.