PREDICTIVE VALUE OF TUBULAR MARKERS FOR THE DEVELOPMENT OF MICROALBUMINURIA IN ADOLESCENTS WITH DIABETES

The predictive value of tubular proteinuria and/or enzyme excretion fo r the development of microalbuminuria in patients with diabetes mellit us was investigated over a period of 7.5 years in 64 children and adol escents without microalbuminuria at baseline. An abnormal urinary excr etion of N-acetyl-beta-D-glucosaminidase (NAG) preceded the increase o f albumin excretion in all 8 patients (12.5%) developing microalbuminu ria during this period (positive/negative predictive value 0.2 and 1.0 , respectively). Also both, the actual as well as the long-term glycem ic control (HbAlc) up to the onset of abnormal NAG excretion were pred ictive for the development of microalbuminuria. Fifty percent of those patients with both an elevated NAG excretion and an HbAlc greater tha n or equal to 9% developed micro-albuminuria within the next 5 years. Therefore, periodic monitoring of urinary NAG excretion should be inco rporated into the follow-up of patients with type 1 diabetes mellitus.