- Clinically significant renal dysfunction as measured by the estimated glomerular filtration rate (eGFR) of < 40 mL/min/1.73m2 as calculated by the MDRD equation: eGFR = 175 x (Creat / 88.4)-1.154 x (Age)-0.203 x (0.742 if female) x (1.212 if African American) (conventional units);