A 30 year-old female laboratory technician under immunosuppressive treatment because of systemic lupus erythematosus (SLE) developed cutaneous leishmaniasis 8 months after accidental percutaneous inoculation of amastigote culture forms of Leishmania mexicana. Leishmania-specific PCR and restriction analysis patterns were identical for both the laboratory strain and the clinical specimen. The lesion was resistant to local paromomycin and oral ketoconazole, but responded to local application of meglumine antimonate. No signs of dissemination or visceralization occurred during the 5-month period of observation. However, a future recurrence cannot be excluded since a persistent infection even after clinical cure has always to be considered in leishmaniasis. Patients under immunosuppressive therapy are possibly at risk of clinical relapse or disseminating infection although there is no experience with regard to leishmaniasis mexicana. Serious infection may require interferon gamma as part of the treatment which may contribute to deterioration of concomitant diseases like SLE. In any case, the exposure of immunodeficient laboratory workers to Leishmania spp. should be avoided.