Leprosy is still a public health concern in Brazil, where more than 30,000 new cases are detected every year. There are few reports of this mycobacteriosis in immunosuppressed patients, despite the increasing number of solid organ transplantation and the use of post-transplant drugs in this country. The authors describe a case of multibacillary leprosy in a renal transplant recipient, detected 12 years after the procedure, and discuss the therapy, adverse effects and management of leprosy reactions in patients immunosuppressed by drugs.