Two autosomal dominant polycystic kidney (ADPKD) cases with advanced renal dysfunction, effectively treated with tolvaptan.

We report here two cases of autosomal dominant polycystic kidney disease (ADPKD) with renal dysfunction that were treated with tolvaptan. Case 1 was a 47-year-old man with a glomerular filtration rate (GFR) of 17.0 ml/min/1.73 m who received tolvaptan treatment (30 mg/day). After treatment, kidney pain was alleviated, and the estimated GFR (eGFR) decline improved from -9.84 ml/min/1.73 m per year to -4.08 ml/min/1.73 m per year, respectively. The rate of increase in total kidney volume was reduced from 18 % per year before treatment to 4 % per year following tolvaptan administration. Case 2 was a 44-year-old man with a GFR of 22.6 ml/min/1.73 m, and the eGFR decline improved from -5.76 ml/min/1.73 m per year before treatment to -3.12 ml/min/1.73 m per year following tolvaptan treatment (30 mg/day). The rate of increase in total kidney volume was also decreased from 10 % per year before treatment to -7 % per year following tolvaptan administration. These results suggested that tolvaptan may be effective in impeding kidney function aggravation and kidney volume increase in ADPKD patients with advanced renal dysfunction.