[Aluminum poisoning in renal dialysis patients: bone histology. Value of quantitative bone biopsy]

Four patients under maintenance dialysis for chronic renal failure were suffering from aluminium toxicity. One showed evidence of encephalopathy, two presented with fractures and one was asymptomatic. Hypercalcaemia was constant, whereas high serum aluminium levels were present in only 2 patients. In all cases, iliac bone biopsy specimens, non-decalcified and stained with Aluminium , were found to contain aluminium deposits along the mineralization fronts, thus confirming the diagnosis of aluminium overload. In addition, biopsies revealed an excess of osteoid tissue with morphological and dynamic signs of osteomalacia (2 cases) or strongly depressed bone formation (2 cases). Histomorphometric bone biopsy appears to be the best mean of diagnosing aluminium intoxication and analyzing its effects on bone remodeling and mineralization. It is also very useful to monitor the treatment.