Conservative treatment of antenatally diagnosed obstructive megaureters: long-term follow up

Abstract

Purpose We retrospectively evaluated our 17 years of experience with the antenatal diagnosis of hydronephrosis, which led to a postnatal diagnosis of an obstructive megaureter and tried to determine the criteria for those who are at risk of surgery. Material and methods 79 children (64 boys and 15 girls) with an antenatal diagnosis of hydronephrosis, which led to a postnatal diagnosis of obstructive megaureter were followed for a period of 17 years (1988-2005). Rt ureterohydronephrosis was seen in 23 children, left in 30 and 26 had bilateral ureterohydronephrosis comprising 105 renal units (RU). According to the SFU classification of hydronephrosis 8 RU were with grade1, 57 with grade 2, 29 grade 3 and 11 with grade 4 postnatal hydronephrosis. Mean ureteral diameter was 1.2 cm. Relative renal function (RRF) was in 82 RU more than 40%, in 18 between 30-40% and in 5 RU less than 30%. Results 25 (31%) children required surgical correction. Mean age at surgery was 14.3 months (range 3-60 months). Univariate analysis revealed that child sex and side of obstruction are not significant predictive factors for surgery. However SFU grade 3-4 of postnatal hydronephrosis (p=0.0057 Odds ratio 0.2892), RRF less than 40% (p=0.0076, Odds ratio 0.2786) and ureteral diameter more than 1.33 cm. (p=0.0188) were significant independent risk factors leading to reimplantation. Conclusions Our data showed that only 30% of children with an antenatal diagnosis of obstructive megaureter required surgical correction. Renal function less than 40%, grade 3 and 4 hydronephrosis and ureteric diameter more than 1.33 cm are statistically significant independent predictive factors for surgery.