Systematic review of the effectiveness of antenatal intervention for the treatment of congenital lower urinary tract obstruction

Background Congenital lower urinary tract obstruction is associated with high mortality and morbidity. Antenatal detection has improved with advances in ultrasound technology, and has allowed the option of antenatal intervention. Objectives To systematically review the literature to evaluate the effectiveness of antenatal interventions to improve perinatal survival and postnatal renal function in congenital lower urinary tract obstruction. Search strategy Extensive electronic searches (database inception 2009) using Medical Subject Headings (MeSH) and keywords, without restrictions. Reference lists of included studies were checked, and all authors were contacted. Selection criteria Studies were selected according to a predefined protocol. The included studies were observational or randomised trials, where an intervention was performed in utero to treat congenital lower urinary tract obstruction, compared with another intervention or no treatment. Data collection and analysis Data were extracted on study design, quality and results to construct 2 x 2 tables. Meta-analysis was performed where possible. Peto ORs with 95% CIs were computed. Main results Prenatal bladder drainage improved perinatal survival compared with no treatment (OR 3.86, 95% CI 2.00-7.45). This effect was amplified in a subgroup with poor predicted prognosis (OR 12.85, 95% CI 1.25-153.03). However, although treatment increases survival, it appears that the residual risk of poor long-term postnatal renal function is uncertain (OR 0.50, 95% CI 0.13-1.90). Author's conclusions Antenatal bladder drainage appears to improve perinatal survival in cases of congenital lower urinary tract obstruction, but may confer a high residual risk of poor postnatal renal function, based on observational studies. Randomised research with long-term follow up is necessary to determine the role of antenatal treatment in clinical practice.