Early prognostic factors of infants with chronic renal failure caused by renal dysplasia

Renal dysplasia (RD) is a common cause of chronic renal failure (CRF) in children. The evolution towards end-stage renal failure is unpredictable due to the paucity of early prognostic factors. In order to identify early prognostic clinical criteria, we have retrospectively analyzed renal function and growth in 11 infants with RD and CRF from birth up to 4 years of age. Children with obstructive RD were not included. Glomerular filtration rate (GFR) was estimated from Schwartz formula. In infants with a GFR below 15 ml/min per 1.73 m2 at 6 months of age (group A, n=5), kidney function did not further improve; 4 reached end-stage renal failure between 8 months and 6 years of age. In contrast, infants with a GFR above 15 ml/min per 1.73 m2 at 6 months of age (group B, n=6) experienced a significant improvement in renal function during follow-up, and none required renal replacement therapy. During the first 3 months of life all infants with RD and CRF developed severe growth retardation. Between 6 months and 4 years of age, children from group B grew significantly better than those from group A. In conclusion, our experience suggests that GFR, estimated from Schwartz formula at 6 months of age, is a useful prognostic factor in infants with RD and CRF. Infants with a GFR below 15 ml/min per 1.73 m2 are at risk of severe growth delay and the need for early renal replacement therapy, whereas those with a GFR above 15 ml/min per 1.73 m2 have a relatively favorable long-term prognosis.