Single-Center Experience in Establishing a Pediatric Kidney Genetics Clinic

Background: Genetic testing is recommended by KDIGO to establish a cause of chronic kidney disease. However, providing this service requires expertise in kidney genetics and genetic counseling and organizational support for navigating insurance approval. Here we describe our experience in establishing a pediatric kidney genetics clinic (KGC) at a single center. Methods: We performed a retrospective chart review of patients referred over 18 months (11/22-4/24) to the Boston Children’s Hospital KGC (Boston, MA, USA) led by two pediatric nephrologists and a certified genetic counselor with expertise in genetic kidney disease. We analyzed clinical and laboratory characteristics, genetic testing results, and clinical utility. Results: 86 patients were referred to the KGC. 53 (61%) were referred for genetic testing after evaluation and pre-test counseling. 46/53 (87%) patients had renal disease while 7/53 (13%) were asymptomatic individuals referred based on a family history of kidney disease. Glomerular and cystic kidney diseases were the most frequent clinical diagnoses (16/53 and 15/53, respectively). We performed genetic testing in 32/53 (60%) patients while 11 families declined testing after counseling. Kidney phenotype-specific (16) or broad kidney disease panels (11) were most frequently ordered. 20/32 (62%) had a pathogenic/likely pathogenic variant identified. The remaining 33 patients seen in the KGC were referred for counseling for prior testing performed by the primary nephrologist or other subspecialty (26/33 and 4/33, respectively) or for CLIA-confirmation of research results (3/33). Of all testing conducted by our clinic, the majority were through a traditional insurance approval process (22/36 tests) while 14/36 were company-based. All variants (including those of uncertain significance) were manually adjudicated by the KGC team, and KGC reanalysis of uncertain variants led to genetic diagnoses in 3 cases. Ultimately, 50/86 (58%) patients seen in our KGC had a genetic diagnosis in one of 29 genes. Alport Syndrome (COL4A3/4/5) was the most frequent genetic diagnosis (11/50 patients). Overall, genetic testing impacted clinical management in 41/65 cases (63%). Conclusion: A dedicated KGC provides utility in providing genetic counseling and expertise in kidney genetic disease as well as streamlining insurance approval.