[Terminal renal failure of pediatric urologic origin according to cause and inverted morphometry]

An age-specific renal reaction becomes evident on comparison of pediatric and adult urology. Reduction of the renal parenchyma by 80% of its bilateral substance because of renal disease can be survived by an adult for some decades with normal blood urea and creatinine, providing the residual parenchyma is histologically normal. Loss of the same proportion of the parenchyma in infancy leads to end-stage renal failure in spite of the better compensatory hypertrophy of the residual renal tissue. This is because the limit of 20% residual substance is only true for a fully developed adult body. While the body is still in the biological growth phase in the second decade of life, a markedly reduced kidney that is no longer growing with the rest of the body is incapable providing the enhancement of renal function needed at this time. The histological implication is glomerulo-sclerotic changes--possibly as a result of hyperfiltration--and the clinical implications, renal failure requiring dialysis or transplantation, the only alternative being a fatal outcome. In a few cases reduced renal work can be compensated function for some years. In all, 46 cases of end-stage renal disease and 13 of chronic retention are detailed according to primary diagnosis.