Progression to end-stage renal disease (ESRD) was noted in all patients with missense mutations (median age, 2.6 months; interquartile range [IQR], 0.8 months to 1.7 years) and in 5 patients with KTS splicing mutations (median, 9.3 years; IQR, 3.3-16.5 years).
Patients with KTS mutations presented at a significantly older age and with a slower progression toward chronic kidney disease (CKD) stage 5, compared with missense mutations.