Recent studies suggest that approximately 10% of patients with chronic kidney disease (CKD) have disease-causing genetic variants, an observation relevant to evaluation of kidney transplant candidates. We retrospectively investigated the diagnostic yield of genetic testing in kidney transplant candidates evaluated at our program (January 1, 2021-December 8, 2022). Inclusion criteria were as follows: first-degree relative(s) with CKD/end-stage kidney disease (ESKD), early-onset CKD, focal segmental glomerulosclerosis, cystic kidney disease, alternative complement pathway-associated diseases, or ESKD of unknown cause. One hundred eleven patients underwent genetic kidney disease testing. The most common indication for testing was early-onset CKD (34.2%), followed by a family history of CKD (23.4%), focal segmental glomerulosclerosis (18.0%), cystic kidney disease (9.0%), alternative complement pathway diseases (3.6%), and ESKD of unknown cause (11.7%). Overall diagnostic yield was 46.9% (52/111), and yield was highest among candidates with a family history of CKD (61.5%; 16/26). Among cases with positive testing, the most common diagnostic variant was APOL1, with 2 renal risk variants identified in 57.7% (30/52), while monogenic causes of CKD were identified in 42.3% (22/52). Genetic testing led to further evaluation or to a different diagnosis than the initial clinical diagnosis in 8.1% (9/111) of the cohort. For 24 transplant candidates, their identified diagnostic variants indicated the need for genetic testing of related living donor candidates; of these, 6 living donor candidates were evaluated and underwent testing, of whom donation was excluded in 1 candidate. Pretransplant genetic testing increases understanding of CKD cause, and provides information for living donor evaluation and risk assessment of posttransplant disease recurrence.
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