['The aim of this study is to test the utility os serum isoamylases and isolipases as determined from patients with renal insufficiency.', 'Serum levels of isoamylases and isolipases were determined in a group of sixty-eight patients with renal disease, 32 of them suffering acute insufficiency and 36 with chronic renal failure undergoing regular hemodialysis, results obtained were compared from a population of 44 healthy adults. We used a new method for isolipases determination in serum based on its separation on agarose gel. Two forms of lipase, L1 and L2, were identified by this method and quantitated by densitometry.', 'Were found a significant increase of pancreatic isoamylase P2 and P/S isoenzymatic ratio in acute patients (p < 0.001) as chronic (p < 0.05). In both groups, the isolipase L1 activity and L1/L2 isoform ratio were showed significantly elevated (p < 0.01). We studied the relationship between isoamylases and isolipases establishing the P2/L2 ratio (normal range < 0.6) showing, in the two pathologic groups, significantly elevated values compared with the control group (p < 0.001) and a positive and significant correlation between the P2/L2 and P/S isoform ratios (r = 0.76, p < 0.05 in acute patients; r = 0.58, p < 0.05 in chronic patients).'] Do [ Isoamylases and isolipases values in the serum from patients wtih renal insufficiency ]?