Effect of immunomodulator pyrimethamine and cimetidine on immunosuppression induced by burn blister fluid.

Despite recent advances in burn wound management, sepsis remains the main cause of death in patients resuscitated after major thermal injury. Increased susceptibility to infections has been related to severe suppression of the immune system.The aim of this study was to induce immune suppression with blister fluid injection, and to modulate immune response by use of cimetidine and pyrimethamine in animal model.Male Balb/c mice were injected with blister fluid intrapritoneally (ip). Fluids were collected from parital-thickness burn blisters and then the delayed type hypersensitivity (DTH) to sheep red blood cell (SRBC) and the effects of different doses of immunomodulators (Cimetidine and Pyrimethamine) on this response were quantitated.A marked suppression of DTH was observed in mice injected with blister fluid. Pyrimethamine and Cimetidine at all three doses caused a significant enhancement of DTH response to SRBC compared with blister fluid injected in control group.This finding represents evidence of a host defense defect within the burn wound and also indicates the blister fluid exhibit immunosuppressor factor that can modulate with immunomadulatory drugs like cimetidine and pyrimethamine.