Aluminium mobilization following renal allograft transplantation may have an immunomodulatory role by reducing the incidence of graft rejection.

Urinary aluminium excretion was prospectively monitored during the first year following first cadaver renal allograft transplantation in 79 consecutive patients. Plasma and urinary aluminium concentrations steadily declined with time. Thirty-five patients had 0-1 episodes of acute graft rejection compared to 44 with two or more rejections; more of the former group had been prescribed aluminium-containing phosphate binders (74% versus 56%, P < 0.02), and following transplantation this group had a persistently greater urinary aluminium excretion, suggesting a greater aluminium body burden. There were no significant differences in terms of gender distribution, blood transfusion, or HLA matching between the groups, thus suggesting that either the subsequent mobilization of aluminium body stores following transplantation and/or the accumulation of aluminium in the reticulo-endothelial system prior to transplantation may have had an immunomodulatory effect in reducing the incidence of renal allograft rejection.