Low dose heparin: efficacious treatment for chronic renal allograft rejection.

Recent data indicate that aside from its anti-coagulant action heparin has potent immunobiological activities inhibiting cell trafficking to a site of antigen. In addition, heparin inhibits smooth muscle cell proliferation and decreases the synthesis of the extracellular matrix proteins. As those phenomena are thought to play a major role in the pathogenesis of chronic allograft rejection, we performed a trial evaluating the efficacy of low dose heparin (5 U/kg/day) in 23 recipients of renal allografts with biopsy-proven rejection. In 16 patients (70%) a tendency for improvement was seen which in 57% was statistically significant. Our data suggest that low dose non-anticoagulant heparin may be an efficacious means for treatment of chronic rejection.