Initial decline in eGFR to predict tolvaptan response in autosomal-dominant polycystic kidney disease.

The initial eGFR decline might be caused by suppressing glomerular hyperfiltration, due to the pharmacological effect of tolvaptan, and/or by reducing renal plasma flow, due to potential volume depletion. The initial eGFR change reflects the tolvaptan effect, can be easily evaluated in clinical practice, and may be useful as one of the clinical indicator for predicting renal prognosis in patients under tolvaptan.