Exploring Water-free Sodium Storage

This study is investigating how the body stores sodium (salt) in ways that are not detectable in regular blood tests — called water-free sodium storage — in people with end-stage kidney disease who are on peritoneal dialysis (a type of home dialysis using the lining of the abdomen). **You may be eligible if...** - You have end-stage kidney disease and are actively doing peritoneal dialysis at home with a working catheter - Your blood pressure is above 130 mmHg (systolic) - Your sodium level in the blood is normal or above (greater than 135 mmol/L) - Your urine output is very low (less than 400 mL per day) - You have been on a stable dialysis prescription for at least 2 months - You have been on peritoneal dialysis for at least 6 months - You are at your target dry weight without signs of fluid overload **You may NOT be eligible if...** - You have poorly controlled diabetes (A1C above 9%) - You have had peritonitis (dialysis-related infection) in the past 6 months or have an active catheter infection - You have significant anemia (hemoglobin below 8 g/dL) - You weigh less than 60 kg - You have bowel conditions causing diarrhea - You have used amiodarone (a heart medication) in the past 6 months Talk to your doctor to see if this trial is right for you.