Curso clínico de 822 crianças com diagnóstico pré-natal de nefrouropatias: desenvolvimento de um modelo de predição clínica de doença renal crônica

Abstract

Introduction and Purpose: The prenatal detection of congenital anomalies of the kidney and urinary tract (CAKUT) has permitted early management of these conditions. This study aims to analyse the clinical course of a large cohort of patients with prenatally detected nephrouropathies. In addition, a risk score that might predict the chance of CKD was also proposed. Patients and Methods: In this retrospective cohort study, 822 patients were prenatally diagnosed with CAKUT and were systematically followed up at a tertiary Renal Unit for a median time of 43 months. Variables included in the analysis: gender, laterality, fetal US findings (isolated vs. associated hydronephrosis), and presence/absence of nephrouropathies. Events of interest: urinary tract infection (UTI), surgical interventions, hypertension, chronic kidney disease (CKD), and death. Survival analyses were performed toevaluate time until occurrence of the events of interest. Predictive model was developed using Cox proportional hazards model and evaluated using C statistics. A prognostic weighting was derived for each variable and a total prognostic risk score was calculated by the sum of these weightings. Results: UTI occurred in 245 (29.8%) children, with higher risk in females [hazard ratio (HR) = 1.3, confidence interval (CI) 95%, 1.02 1.7, P = 0.047]. Twenty-two patients (2.7%) had hypertension. Twelve patients (1.5%) died during follow-up. Forty-nine (6%) patients developed CKD. The risk of CKD was greater in patients with associated hydronephrosis (HR = 5.2, CI95%, 2.9 9.3, P < 0.001). The most accurate model included bilateral hydronephrosis, oligohydramnios, baseline serum creatinine, and postnatal diagnosis as hypodysplasia and obstructive uropathy in the development cohort. By survival analysis itwas estimated that at 10 years of age, the probability of renal survival was about 98%, 86% and 52% for those patients assigned to low-risk, medium and high-risk groups, respectively. Conclusions: The clinical course of prenatally detected CAKUT was heterogeneous. Thepredictive risk model of CKD may contribute to early identification of a subgroup of CAKUT patients at high risk for the development of CKD.