The Effects of Patiromer on Serum Potassium Level and Gut Microbiome of ESRD Patients With Hyperkalemia

Inclusion Criteria: * Subjects on stable hemodialysis for more than 90 days. * Age 18-85 years. * Persistent hyperkalemia, defined as elevated serum potassium \> 5.0 mEq/L in more than 2 occasions during the previous 3 months. Exclusion Criteria: * Use of pre- or probiotics during the past 2 months * Use of antibiotics within the past 2 months, if the patient received a single course of antibiotic. * Presence of chronic wound infection and osteomyelitis * Inflammatory bowel disease, chronic diarrhea, current C. difficile infection * Liver cirrhosis or chronic active hepatitis * Treatment with immunosuppressive medications in the past 6 months or more than a week of treatment with prednisone \> 10 mg in the last 3 months * Anticipated kidney transplant within 9 months * Expected survival \< 9 months * Pregnancy, anticipated pregnancy, or breastfeeding * Incarceration * Participation in another intervention study * severe anemia defined as hemoglobin \< 8.0 g/dl any time during the last 2 months