Plasma prorenin activity and complications in children with insulin-dependent diabetes mellitus.

Background: Renin, secreted into the blood by the juxtaglomerular cells of the kidneys, is derived from a larger precursor, prorenin. Plasma prorenin activity is increased in patients with insulin-dependent (Type I) diabetes mellitus who have microvascular complications of their disease. We undertook this study to determine prospectively whether rising prorenin activity can predict the development of complications in young patients with Type I diabetes.

Prorenin and vascular complications of diabetes.

A high plasma prorenin is a marker of microvascular complications of diabetes. We have followed 56 adults and 120 children with uncomplicated insulin-dependent (type 1) diabetes. When plasma prorenin rises above the normal range in an adolescent or adult with type 1 diabetes, signs of nephropathy, retinopathy, or neuropathy follow within one to two years.

Plasma prorenin and renin in childhood and adolescence.

We studied 108 subjects (age range, 4 to 76 years) to determine the effect of age on prorenin (inactive renin), active renin, and plasma renin activity in normal children, adolescents, and adults. Children and adolescents had lower prorenin concentrations and higher plasma renin activity and active renin concentrations than did adults. Prorenin concentrations were positively correlated with age over the range of 4 to 76 years, while plasma renin activity and active renin concentration were negatively correlated with age.

Microalbuminuria and increased plasma prorenin. Prevalence in diabetics followed up for four years.

When urinary albumin excretion was measured by radioimmunoassay, most diabetics excreted more albumin than nondiabetic subjects. Microalbuminuria was defined as an albumin excretion greater than 30 mg/g of urinary creatinine, more than twice the upper limit of normal. Intermittent microalbuminuria was found in 20% of patients with insulin-dependent diabetes mellitus (IDDM) or non-insulin-dependent diabetes mellitus (NIDDM).

The long-term course of cyclosporine-associated chronic nephropathy.

We evaluated a chronic renal injury in 37 cardiac transplant recipients treated for 12 to 24 months with cyclosporine (CsA). Twenty-four cardiac transplant recipients treated with azathioprine for more than 24 months served as controls. Despite equivalent cardiac performance, GFR in those treated with CsA was depressed, 47 +/- 3 versus 94 +/- 4 ml/min/1.