Aluminium-induced, reversible microcytic anemia in chronic renal failure: clinical and experimental studies

Ten chronic hemodialysis patients with severe aluminium (Al) intoxication developed a microcytic anemia despite oral iron supplementation. Their microcytosis was reversible after deionization of the dialysis water. Ten age and sex matched hemodialysis patients who were not Al intoxicated but who had a comparable treatment schedule and time on dialysis had no such microcytosis. In order to investigate a possible direct role of Al we intoxicated uremic rats by daily (6/7 days a week) intraperitoneal injections of 30 nmoles/day of aluminium. After 3 months, the Al-intoxicated uremic rats had a significantly lower hematocrit (34.7%), hemoglobin (12.0 g/dl), and MCV (52.5 fl) than the control, vehicle-injected uremic animals (37.4%, 13.1 g/dl and 60.4 fl., respectively). The reticulocyte counts of the intoxicated rats were increased. Serum iron and transferrin iron binding capacity were unchanged. Thus aluminium intoxication of the uremic organism leads to a microcytic anemia possibly by interfering directly with normal hemoglobin synthesis.