Multidrug therapy (MDT) causes a decrease in the bacterial burden in leprosy patients. Does the decrease in the antigenic stimulation of the immune system have an effect on cytokine production?Methods
The effect of treatment on serum cytokines was evaluated in 36 leprosy patients and 35 reactional leprosy patients and compared with that in 20 age- and sexmatched healthy individuals. The enzyme-linked immunosorbent assay (ELISA) technique was used to measure serum levels of interleukin-2 receptor (IL-2R), interleukin-10 (IL-10), and interleukin-1beta (IL-1β) before and after treatment. These cytokines represent T-helper 1 (TH1), T-helper 2 (TH2), and macrophage cytokines, respectively.Results
The studied serum cytokines were significantly reduced after 1 year of treatment in leprosy patients. The degrees of reduction were significantly positively correlated with a reduction in the bacterial index (BI) and morphologic index (MI). After 1 year of MDT (but not 6 months), paucibacillary (PB) patients showed a significant reduction in all the studied serum cytokines to levels comparable with those of healthy controls. Multibacillary (MB) patients also showed a significant reduction in all the studied serum cytokines, but the levels were still significantly higher than those of healthy controls. Leprosy patients with high levels of serum IL-1β were more susceptible to the development of reactions after the initiation of treatment. Corticosteroid therapy of reactional patients resulted in a significant reduction in the studied serum cytokines to levels similar or lower than those of nonreactional leprosy patients. The dose of steroids showed a significant positive correlation with the amount of decrease in IL-1β.Conclusions
MDT caused a reduction in serum cytokines correlated with a reduction in the bacterial burden. It is advisable to continue MDT for PB patients for 1 year. Serum IL-1β levels may have a prognostic value for the susceptibility of leprosy patients to the development of reactions.