RE-EVALUATION OF THE ORAL ALUMINIUM PHOSPHATE BINDERS IN NEPHROLOGY PRACTICE

INTRODUCTION

Aluminium (Al) toxicity may lead to mainly three disorders in haemodialysis (HD) patients: aluminium-related bone disease (osteomalacia), microcytic anemia and neurological dysfunction (Sandhu G-2011 [1]). This toxicity is associated with exposure to contaminated water of dialysate preparations or ingestion of aluminum-containing binders used for the treatment of hyperphosphatemia (Willhite CC-2012 [2]). The aim of this study was to determine the risk of Al toxicity in HD patients receiving aluminium hydroxide without the confounding factor of aluminium-contaminated dialysis (Pepper R-2011 [3] (full text); Mudge DW-2011 [4] (full text)).

METHODS

We studied 82 current haemodialysis patients. Serum aluminium concentrations are monitored every six months in our unit. For the correct sampling of aluminium all the precautions were taken: fasting for at least eight hours, upright for at least 30 minutes, prohibition of drinks contained in aluminium cans.

RESULTS

15 patients received sevelamer in an average dose of 6,4 grams daily; 28 patients received lanthanum (average dose 2,5 grams daily); 12 patients received calcium acetate/magnesium carbonate (average dose 1,5 grams daily); 15 patients received sevelamer carbonato (average dose of 4,8 grams daily) and 12 patients received aluminium hydroxide (average dose 800 mg daily) (Figura 1). In all patients the mean serum phosphate concentration was 4,9 mg/dl. Serum Al concentrations were low in all patients (mean concentration 7,8 mcg/lt) (Figura 2). Only one patient had concentration over 55 mcg/lt but no clinical evidence of toxicity.

CONCLUSIONS

Although this is a small study, we observed no correlation between serum Al concentration and the total amount of Al ingested. No patient had clinical evidence of Al toxicity despite the administration of aluminium hydroxide. Therefore, with due prudence, although in accord to the K/DOQI and KDIGO guidelines in our hospital we promote the use of the newer phosphate binders, we should re-evaluate the risk of using Al-based phosphate binders in HD population.