Clinical value of urinary excretion of N-acetyl-beta-glucosaminidase in diabetic retinopathy]

To test N-acetyl-beta-glucosaminidase (NAG) urinary excretion, early renal damage biochemical marker, in patients with non-insulin-dependent diabetes mellitus grouped according to the degree of retinopathy, establishing its relationships to retinal involvement.We make a prospective study of 144 type 2 diabetic patients and 94 healthy subjects. We realized an ocular exploration that included fluorescein angiography and a biochemical study that included the determination of NAG urinary excretion in all of them. The patients were grouped depending on their retinal disease. 76 subjects without retinal abnormalities (40 men and 36 women), 30 with early nonproliferative diabetic retinopathy (13 men and 17 women) and 21 subjects with proliferative diabetic retinopathy (10 men and 11 women). Results were analyzed by using statistical analyses.Our results showed that there exist an increase in the urinary excretion of NAG according to the degree of diabetic retinopathy advance. We also highlight the biggest urinary excretion of NAG in the diabetic patients without retinal involvement regarding healthy subjects.There is a parallelism between renal and retinal complications in type 2 diabetes mellitus as other authors had demonstrated previously for the type 1 diabetes mellitus.