ARF in children with minimal change nephrotic syndrome may be related to functional changes of the glomerular basal membrane.
BACKGROUND
Acute renal failure (ARF) is a rare complication in children with minimal change nephrotic syndrome (MCNS). Several etiologic factors (renal vein thrombosis, side effect of such drugs as nonsteroidal anti-inflammatory drugs, and infections) have been described, but often such conditions are lacking, and hemodynamic derangements or changes in glomerular permeability are suspected.


METHODS
We assessed the role of alterations in renal perfusion and glomerular permeability by measuring clearances of inulin and para-aminohippurate before and during intravenous administration of a 20% albumin solution in patients with MCNS and oliguric ARF (serum creatinine > 1 mg/dL [88 micromol/L], urine output < 0.5 mL/kg body weight/h).


RESULTS
Eleven patients aged 2.5 to 15 years with biopsy-proven MCNS were studied. Before albumin administration, all patients had a significantly decreased glomerular filtration rate (GFR), whereas most renal plasma flow (RPF) values were within the normal range. This resulted in a significantly decreased filtration fraction (FF; GFR/RPF x 100), which was extremely low (<7%) in 4 patients. There was a heterogeneous response to albumin administration. Albumin infusion tended to increase RPF, but changes did not reach statistical significance. Some patients showed an increase in glomerular filtration, whereas in others, it decreased. In 7 patients, FF remained unchanged or decreased even further.


CONCLUSIONS
Our data suggest that, although in some patients decreased intravascular volume may contribute to reduced renal function, changes in glomerular permeability may have a major role in ARF occurring in uncomplicated MCNS.
Department of Pediatric Nephrology, University of Gent, Belgium.
Johan
J
Vande Walle
Reiner
R
Mauel
Ann
A
Raes
Kristof
K
Vandekerckhove
Raymond
R
Donckerwolcke
D058186:Acute Kidney Injury / Q000209:etiology*; D000293:Adolescent; D002463:Cell Membrane Permeability; D002648:Child; D002675:Child, Preschool; D005919:Glomerular Filtration Rate; D005920:Glomerular Mesangium; D006801:Humans; D007444:Inulin; D007677:Kidney Function Tests; D009402:Nephrosis, Lipoid / Q000150:complications / Q000503:physiopathology*; D017596:Renal Plasma Flow, Effective; D010130:p-Aminohippuric Acid
D007444:Inulin; D010130:p-Aminohippuric Acid