Prognostic value of serum creatinine levels in children with posterior urethral valves treated by primary valve ablation

Abstract

We evaluated the prognostic value of serum creatinine level at presentation and nadir creatinine during follow up for future renal function (RF) in children with posterior urethral valves (PUV). Between 1987 and 2004, 120 cases of PUV were treated initially at our hospital with valve ablation. Initial assessment included serum creatinine measurement, urine analysis and culture, renal ultrasonography and voiding cystourethrography. After valve ablation, renal ultrasound and serum creatinine measurement were repeated and thereafter during visits until the end of follow up. Follow up ranged from 2 to 12 years (mean=4.4). Renal insufficiency (RI) developed at the end of follow up in 44 patients (36.5%). The mean initial and nadir serum creatinine in the RI group was higher than in the normal RF group (P<0.05). With a cut-off value of 1mg/dl for initial and nadir serum creatinine, the incidence of RI was significantly different (P<0.05). Our data confirm the high prognostic value of nadir serum creatinine after relief of valvular obstruction. Further, the serum creatinine level before valve ablation correlates significantly with long-term RF in children with PUV.