Biochemical and hematological changes in low-level aluminum intoxication

The aim of this study was to investigate the biochemical and hematological changes in patients on routine hemodialysis treatment when they were accidentally exposed to moderately high serum aluminum concentrations during a period of time of less than four months. We studied the changes in biochemical and hematological measurements in 33 patients on dialysis in our hospital before and during the exposure to about 0.85 pmol/l of aluminum in dialysis water due to a malfunction of the reverse osmosis system of water purification. Patients showed a decrease in the hemoglobin concentration from 115+/-12.4 g/l to 108+/-12.2 g/l (p=0.026) and in the mean corpuscular hemoglobin concentration from 5.15+/-0.22 to 5.02+/-0.30 mmol/l (p=0.014). Ferritin was decreased from 243+/-192 microg/l to 196+/-163 microg/l (p=0.047) and transferrin saturation from 0.20+/-0.06 to 0.15+/-0.07 (p=0.004). Biochemical measurements related to calcium-phosphate metabolism did not change. Otherwise, all patients showed an increase in serum aluminum from 0.56+/-0.44 to 1.63+/-0.52 micromol/l (p<0.001). No differences were detected in serum aluminum between patients receiving and not receiving oral aluminum salts. Even moderately high aluminum concentrations maintained during a short period of time could produce significant hematological alterations and a depletion of body iron stores before clinical manifestations were evident.