Prediction of Renal Prognosis in Patients with Autosomal Dominant Polycystic Kidney Disease Using PKD1/PKD2 Mutations

Autosomal dominant polycystic kidney disease (ADPKD) patients with PKD1 mutations, particularly those with truncating mutations, show poor prognosis. However, the differences in disease progression with different mutation types are unclear. Here, a comparative study was conducted on the renal prognosis of patients with ADPKD who were categorized based on genotype (PKD1 versus PKD2 mutation), mutation type (truncating mutation: nonsense, frameshift, splicing mutation, and large deletion; non-truncating mutation: substitution and in-frame deletion), and mutation position. A total of 123 patients visiting our hospital were enrolled. Renal prognosis was poor for those with PKD1 splicing, PKD1 frameshift, and PKD2 splicing mutations. Despite the truncating mutation, the renal prognosis was relatively favorable for patients with nonsense mutations. Three out of five patients with PKD2 mutation required renal replacement therapy before 58 years of age. In conclusion, we showed that renal prognosis differs according to mutation types in both PKD1 and PKD2, and that it was favorable for those with nonsense mutations among patients with PKD1 truncating mutations. It was also confirmed that renal prognosis was not always favorable in patients with PKD2 mutations. A detailed assessment of mutation types may be useful for predicting the renal prognosis of patients with ADPKD.