Clinical implications of apolipoprotein L1 testing in patients with focal segmental glomerulosclerosis: a review of diagnostic and prognostic implications.

Focal segmental glomerulosclerosis (FSGS) is a leading cause of nephrotic syndrome, contributing to 40% of adult and 20% of pediatric cases globally. Apolipoprotein L1 (APOL1) genetic variants, particularly G1 and G2 alleles, play a pivotal role in FSGS pathogenesis, particularly among African-Americans, where 30-40% carry these risk alleles.