Chromosomal Microarray Analysis in Fetuses with Congenital Anomalies of the Kidney and Urinary Tract: A Prospective Cohort Study and Meta-analysis

Objective: To evaluate the usefulness and incremental diagnostic yield of chromosomal microarray analysis (CMA) compared with standard karyotyping in fetuses with congenital anomalies of the kidney and urinary tract (CAKUT).

Methods: A prospective cohort study and systematic review of the literature were conducted. In the prospective cohort study, 123 fetuses with CAKUT, as detected by prenatal ultrasound at our center, were enrolled and evaluated using karyotyping and CMA. In the meta-analysis, articles in PubMed and ISI Web of Knowledge databases describing copy number variations (CNVs) in prenatal cases of CAKUT were included.

Results: Among the 123 fetuses in our prospective cohort study, 13 fetuses were detected with chromosomal abnormalities or submicroscopic chromosomal abnormalities by both karyotyping and CMA. In the remaining 110 fetuses, four pathogenic CNVs in four fetuses were only detected by CMA, indicating an excess diagnostic yield of 3.6%. Six publications and our own study met the inclusion criteria for the meta-analysis. In total, 615 fetuses with CAKUT were included. The pooled data from all of the reviewed studies indicate that the incremental yield of CMA over karyotyping was 3.8%.

Conclusion: The use of CMA provides a 3.8% incremental yield of detecting pathogenic CNVs in fetuses with CAKUT and normal karyotype.