Steroids in leprosy type 1 (reversal) reactions: mechanisms of action and effectiveness

Steroids are widely used for the treatment of leprosy reactions. The effect iveness of steroid treatment is variable, with only 60% of patients regaini ng nerve function. Sequential skin biopsy specimens, obtained from 15 patie nts with type 1 (reversal) reactions, have been studied to document the cyt okine profile and cellularity of the lesions. All of the patients were plac ed on a standard course of steroids after the first biopsy. Subsequent biop sies were performed seven, 28 and 180 days later. The specimens were staine d for interferon-gamma (IFN gamma), interleukin-12 (IL-12) and inducible ni tric oxide synthase (iNOS). After the first biopsy, all patients were place d on a standard reducing course of steroids beginning at 30 mg daily. By day 7, treatment with prednisolone showed little effect on the cellulari ty and cytokine profiles. However, by day 28, significant decreases of IFN- gamma, IL-12 and iNOS were found for most patients. Some patients maintaine d cytokine production at day 28 and even at day 180. These data illustrate the strong Th1 profile of type I reactional lesions, the relatively slow re sponse to therapy, and the continuing activity after treatment with steroid s for 180 days. The variation of individual responses emphasizes their impo rtance. Additional prospective studies will be required to determine whethe r patients with high intra-lesional levels of cytokine are at risk of recur rent reactions. The need for studies both of different glucocorticoids and of other non-steroidal immunosuppressants for the treatment of reactions is discussed.