Renal function and albumin excretion during exercise in children during remission of the minimal change nephrotic syndrome.

Six patients with the minimal change nephrotic syndrome in remission and seven healthy controls were investigated with regard to renal haemodynamics and albumin excretion before, during and after exercise. The glomerular filtration rate and effective renal plasma flow were determined by a standard clearance method, employing continuous infusion of inulin and para-aminohippuric acid. Microalbuminuria was measured by an immunoturbidimetric method. The work load was standardized at 70% of the maximal working capacity and was applied for 20 min. During exercise there was a significant fall in the glomerular filtration rate and effective renal plasma flow and a significant rise in the filtration fraction. The pattern of renal haemodynamic changes did not differ between the groups. Nor was there any statistically significant difference in urinary albumin excretion, although the exercise-induced increase in albumin excretion of the controls did not reach statistical significance. It is concluded that the renal haemodynamics and urinary albumin excretion of children having long remissions of the minimal change nephrotic syndrome are normal at rest as well as during and after a submaximal exercise test.