- We will enroll adult subjects (greater than or equal to 18 years of age), male or female, and of all racial backgrounds/ethnicities. In this cohort, we will include subjects with kidney disease or without kidney disease (healthy volunteers). We will start with subjects with preserved glomerular filtration rate (eGFR-Cr greater than or equal to 60 ml/min/1.73m2) but may expand to include individuals with lower GFR in a later study. We will estimate glomerular filtration rate (eGFR) using the 2009 CKD-EPI creatinine equation.