Kidney Week

Abstract: TH-PO356

Intracellular ATP and Inorganic Phosphate Depletion During Maintenance Hemodialysis

Session Information

• Dialysis: Dialysate and Clearance
  October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Dialysis

• 701 Dialysis: Hemodialysis and Frequent Dialysis

Authors

• Chazot, Guillaume, Hospices Civils de Lyon, Lyon, France

Guillaume Chazot,

• Lemoine, Sandrine, Hospices Civils de Lyon, Lyon, France

Sandrine Lemoine,

• Kocevar, Gabriel, CREATIS (UMR 5220 CNRS & U 1044 INSERM), Université Claude Bernard Lyon 1, France, Villeurbanne, France

Gabriel Kocevar,

• Kalbacher, Emilie, Hospices Civils de Lyon, Lyon, France

Emilie Kalbacher,

• Normand, Gabrielle Laetitia, Hospices Civils de Lyon, Lyon, France

Gabrielle Laetitia Normand,

• Sappey-Marinier, Dominique, University of Lyon, Lyon, France

Dominique Sappey-Marinier,

• Rouviere, Olivier, Hospices Civils de Lyon, Department of Urinary and Vascular Imaging, Hôpital E. Herriot, Lyon, France; Université de Lyon, Lyon, France; Université Ly, Lyon, France

Olivier Rouviere,

• Juillard, Laurent, University of Lyon, Lyon, France

Laurent Juillard,

Background

The origin of depurated phosphate during hemodialysis (HD) remains unknown. Using phosphorus magnetic resonance spectroscopy (³¹P-MRS), we previously showed in an acute kidney failure model in pig, an increase of intracellular inorganic phosphate (Pi) concentration during hemodialysis associated with a decrease in ATP. This result strongly supports the hypothesis that depurated phosphate could come from the intracellular space. The aim of this study was to measure intracellular Pi in patients during maintenance HD using ³¹P-MRS.

Methods

Eleven maintenance HD patients were included in the CIPHEMO (Intracellular ATP and Pi Concentrations measurements in HEMOdialysis patients) study, a single-center prospective trial. They underwent a ³¹P-MRS exam using a 3-Tesla system and a surface coil placed over the calf muscle region for measuring Pi and ATP contents during a standard hemodialysis session (4 hours). ³¹P-MR spectra were acquired before, during (every 152 seconds) and after the HD session. Phosphatemia, depurated phosphate and calcemia were monitored during HD and parathyroid hormone levels were measured at the beginning and at the end of the session. Calcium balance was also measured.

Results

Intracellular Pi and βATP kinetics can be described in 2 phases. During the first hour of HD, phosphatemia decreased rapidly (-41%, p<0.001) whereas intracellular Pi didn’t change (p=0.9) and intracellular βATP decreased (-17%, p=0.038). After 1 hour of HD, phosphatemia decreased slowly, intracellular Pi decreased (p=0.001) and βATP remained constant until the end of the session (p=0.46). Depurated phosphate is nearly constant during the session. Calcemia increased (p<0.01) and parathyroid hormone decreased (p<0.05) during HD. Calcium balance is positive (mean of 17.1 mmol).

Conclusion

This study showed a significant decrease in both intracellular ATP and Pi during hemodialysis. These findings, reported for the first time in HD patients, support the hypothesis that a large part of depurated phosphate could come from the intracellular space in patients on maintenance hemodialysis.