RESUMO
OBJECTIVE: The aim of this study was to test the utility of serum alkaline phosphatase isoenzymes determination from patients with renal insufficiency. MATERIAL AND METHODS: Serum levels of alkaline phosphatase isoenzymes were determined in a group of 58 patients: 22 of them suffering acute renal insufficiency (ARI) and 36 with chronic renal failure (CRF) undergoing regular hemodialysis, results obtained were compared from a population of 30 healthy adults. Intestinal, bone, liver, macromolecular and intestinal variant isoenzymes, were separated by electrophoresis on agarose gel and quantified using a densitometer. RESULTS: Were found a significant increase the total alkaline phosphatase activity in both pathologic groups (p < 0.05 in ARI and p < 0.01 in CRF). Isoenzymatic profiles showed: increase of the bone fraction (p < 0.05 in ARI and p < 0.001 in CRF), decrease of the liver isoenzyme (p < 0.001) in both groups, macromolecular fraction elevated in acute patients (p < 0.05) and a significant increase of the intestinal and intestinal variant isoenzyme in the chronic patients (p < 0.001). CONCLUSION: The renal insufficiency modified the normal distribution of alkaline phosphatase isoenzymes and the study of their serum levels could be an effective non-invasive marker, for the evaluation of bone disease and intestinal disorders associated with renal failure.