Genotype-Clinical Correlations in Polycystic Kidney Disease with No Apparent Family History

Abstract

Background: Genetic characteristics of polycystic kidney disease (PKD) patients without apparent family history were reported to be different from those with a positive family history. However, the clinical course of PKD patients with no apparent family history is not well documented in the literature. Methods: We evaluated the relationship between genotype and the clinical course of 62 PKD patients with no apparent family history. Results: The annual decline of renal function was faster in the patients with PKD1/PKD2 mutation (PKD1 truncating [–3.08; 95% CI –5.30 to –0.87, p = 0.007], PKD1 nontruncating [–2.10; –3.82 to –0.38, p = 0.02], and PKD2 [–2.31; –4.40 to –0.23, p = 0.03]) than in the other patients without PKD1/PKD2 mutation. Similar results were obtained after adjustment for gender, age, estimated glomerular filtration rate (eGFR), height-adjusted total kidney volume (TKV), and mean arterial pressure (MAP). There was no significant difference in the annual decline of renal function among the different PKD1/PKD2 groups, but Kaplan-Meier analysis showed that progression to eGFR < 15 mL/min/1.73 m2 was significantly faster in PKD1 truncating group (p = 0.05). The annual rate of TKV increase was larger in the patients with PKD1/PKD2 mutation (PKD1 truncating [4.63; 95% CI 0.62–8.64, p = 0.03], PKD1 nontruncating [3.79; 0.55–7.03, p = 0.02], and PKD2 [2.11; –1.90 to 6.12, p = 0.29]) than in the other patients without PKD1/PKD2 mutation. Similar results were obtained after adjustment for gender, age, eGFR, and MAP. Conclusion: Detection of PKD1/PKD2 mutation, especially PKD1 truncating, is useful for predicting the renal outcome and rate of TKV increase in PKD patients with no apparent family history.