Leprosy and its reactional episodes: Serum levels and possible roles of omega-3 and omega-6-derived lipid mediators

The disease leprosy is caused by Mycobacterium leprae. The disease displays a spectrum of clinical manifestations relating to the stage of the infection and the pathogen-specific immune response. The most frequent M. leprae-specific hypersensitivity reactions are erythema nodosum leprosum (ENL) and type-1 (reversal) reaction (T1R). Omega-3 and omega-6 fatty acid-derived lipid mediators are involved in the regulation of these M. leprae-specific inflammatory and immune responses. Studies on lipid mediators showed their presence during different manifestations of leprosy-before and after multidrug therapy (MDT) and during T1R. This review aims to compare the lipid mediators at different stages of the disease. This review also presents new data on the significance of lipid mediators (cysteinyl leukotrienes and leukotriene B4, prostaglandin E2 and D2, lipoxin A4 and resolvin D1) on ENL.