Plasma prorenin levels may predict persistent microalbuminuria in children with diabetes

Diabetic microangiopathy is characterized by increased prorenin concentrations. In the present study, we evaluated plasma prorenin concentrations in a large group of adolescents with onset of diabetes during childhood to determine whether increasing prorenin levels may predict the development of persistent microalbuminuria. Ninety-seven young diabetic patients were studied; they were divided according to the presence of persistent microalbuminuria, at the end of follow-up, into group A and group B (patients who did not develop and who developed persistent microalbuminuria, respectively). One hundred and two healthy subjects, matched for age and sex, were also selected. Patients were followed up for at least 10 years. At the beginning of the study there were no significant differences in prorenin levels between either the two diabetic groups or the healthy controls. During follow-up, an increase in plasma prorenin started at 4 years and became statistically significant (P<0.01) 3 years before the onset of persistent microalbuminuria. No correlation was found between plasma prorenin levels and HbA1c percentages. In conclusion, an increased concentration of prorenin in plasma precedes the elevation of albumin excretion rate (AER) and, therefore, can be useful for identifying patients with onset of diabetes during childhood at risk of developing incipient nephropathy later in life. Received: 16 March 2000 / Revised: 21 September 2000 / Accepted: 23 September 2000