Congenital solitary kidney size at birth could predict reduced eGFR levels later in life.

Abstract

To evaluate the impact of congenital solitary functioning kidney (CSFK) length, measured early in life, on the eGFR levels during the follow-up. We retrospectively selected 162 CSFK patients undergoing, within 60 days of life, renal length (RL) measurement by ultrasound. We divided the population in: Group 1 = RL ≥ 2 standard deviation score (SDS). Group 2 = RL < 2 SDS and showing RL ≥ 2 SDS during the follow-up. Group 3 = RL < 2 SDS and showing RL < 2 SDS during the follow-up. development of eGFR below the range of normality. The median follow-up period of the overall population was 6.2 years (range 2-21.5 years). The cumulative proportion of patients free of primary outcome at 15 years of age was 96.4% in group 1, 64.6% in group 2, and 45.6% in group 3 (p = 0.03). The RL > 2 SDS within 60 days of life was a significant protective factor (hazard ratio = 0.13; 95% C.I. 0.02-0.97) against development of primary outcome. RL ≥ 2 SDS within 60 days of life could identify a population of CSFK with reduced risk of presenting reduced eGFR levels later in life.