Is fetal isolated double renal collecting system an indication for chromosomal microarray?

Area of Science:

• Urology
• Prenatal Diagnosis
• Genetics

Background:

• Duplication of the renal collecting system is a common urinary tract anomaly.
• Prenatal ultrasound often identifies this finding, raising questions about associated genetic risks.

Purpose of the Study:

• To assess the risk of chromosomal aberrations in isolated prenatal diagnosis of duplex renal collecting system.
• To compare chromosomal microarray analysis (CMA) findings in these pregnancies to the general population risk.

Main Methods:

• Retrospective analysis of CMA data from pregnancies with isolated duplex renal collecting system.
• Comparison of CMA results with a systematic review of normal ultrasounds and local data for maternal request CMA.

Main Results:

• 1.4% of pregnancies with isolated duplex renal collecting system had pathogenic CMA findings.
• This rate was not significantly different from the general population risk for abnormal CMA results.

Conclusions:

• Isolated duplex renal collecting system on prenatal ultrasound does not warrant routine invasive CMA testing.
• Current findings suggest CMA is not more beneficial in these cases than in the general population.