RESUMO
BACKGROUND: The recommended dose of desferrioxamine for the treatment of aluminium intoxication is 5 mg/kg/week. However, there are no data about the efficiency of lower doses. The objective of this study was to investigate the capacity of very low doses of desferrioxamine in the generation of ultrafiltrable aluminium. METHODS: Five patients undergoing haemodialysis with a similar biochemical profile and serum aluminium levels >40 microg/l were studied. The three different doses of desferrioxamine used (0.5, 2.5 and 5.0 mg/kg) were administered randomly to each patient at 1 week intervals. Total and ultrafiltrable serum aluminium was measured before and 44 h after the administration of desferrioxamine. RESULTS: All doses of desferrioxamine significantly increased the total serum aluminium; no differences were found between 2.5 and 5.0 mg/kg. The total serum aluminium levels doubled with the 2.5 and 5.0 mg/kg doses, while the increase with 0.5 mg/kg was lower (32.6%, P<0.05). Ultrafiltrable aluminium increased with the three doses; from 7.1+/-2.8, 3.9+/-0.6 and 7.5+/-4.1 to 25.7+/-7.3, 44.3+/-10.1 and 59.1+/-19.8 microg/l, respectively (P<0.05). The efficiency of each dose was calculated using the ratio between the increase in ultrafiltrable aluminium and the dose of desferrioxamine administered. The efficiency ranged from 10.3+/-3.9 for the higher dose (5 mg/kg) to 37.2+/-10.3 for the lower dose (0.5 mg/kg). CONCLUSIONS: Our results suggest that very low-dose desferrioxamine (>5 mg/kg) increases the ultrafiltrable (potentially dialysable) aluminium.
