Use of methotrexate for leprosy reactions. Experience of a referral center and systematic review of the literature

Background: Patients with leprosy can present with systemic inflammatory complications called leprosy reactions (LR), which can be severe and cause a loss of nerve function. The treatment of choice is prolonged corticosteroid therapy, frequently associated with severe side effects. We have used methotrexate as a corticosteroid-sparing regimen with good results.

Methods: To evaluate the role of methotrexate in managing LR, we performed a systematic review of the literature including our cases. We evaluated studies, prospective and retrospective, in both adults and children, which included any dose/regimen of methotrexate for the treatment of LR type 1 or 2.

Results: The systematic search revealed 261 records that yield 21 patients including our 3 cases (19 adults/two children), who were treated with methotrexate for LR type 1 and 2. There were 14 males. Median age was 35 years (P₂₅-P₇₅ 28 to 52). Patients showed lepromatous (7), borderline lepromatous (9) or borderline tuberculoid (3) leprosy, among the 19 cases in which the type of leprosy was specified. As for the type of LR, 15 patients showed erythema nodosum leprosum (ENL), five showed LR type 1 and one showed polyarthritis and previous ENL. Methotrexate at weekly doses ranging from 7.5 mg to 20 mg (median 15 mg per week), typically administered with low-dose corticosteroids, was effective and safe as a corticosteroid-sparing agent.

Conclusions: Methotrexate could be a suitable ancillary treatment or alternative to corticosteroids, especially in populations who are more prone to its adverse events. However, this evidence is based only on case reports and short clinical series.