Diagnostic and clinical utility of genetic testing in children with kidney failure

Background Genetic kidney disease is well established as an important cause of pediatric kidney failure, and genetic testing might increase diagnostic accuracy, but evidence is limited. This study was conducted to determine the diagnostic yield and clinical impact of genetic testing for children with kidney failure. Methods Patients who were diagnosed with kidney failure before 19 years of age at Children’s Hospital of Fudan University from 2009 to 2018 and received next-generation sequencing (NGS) were enrolled. The results for likely pathogenic variants in genes known to cause chronic kidney disease (CKD) were analyzed. Results A molecular diagnosis was identified in 39.9% (75/188) of children with kidney failure. Specific subtype of clinical category was discerned in 54 (72.0%) patients, kidney disease was reclassified in 7 (9.3%) patients, the unknown etiology of 5 (6.7%) patients was molecularly diagnosed, and the clinical diagnoses of the other 9 (12.0%) patients were confirmed. In addition, genetic diagnosis was considered to have contributed to clinical management, including negating the need for kidney biopsy (26/75, 34.7%), avoiding immunosuppressive therapy (24/75, 32.0%), changing surveillance (48/75, 64.0%), guiding specific treatment (21/75, 28.0%), and guiding peri-transplant management and options for kidney transplantation (12/75, 16.0%). Furthermore, cascade testing was subsequently offered to 34.7% (26/75) of families. Conclusions Genetic testing identified a molecular diagnosis in nearly 40% of children with kidney failure. Our results confirm that in children with kidney failure, genetic testing can not only establish a specific molecular diagnosis, but has a significant impact on clinical management. Graphical abstract