title: Inorganic phosphorus homeostasis during the first hour of dialysis.
abstract: OBJECTIVE
  Hyperphosphatemia is a well-recognized complication of chronic kidney disease, and phosphorus kinetics during hemodialysis (HD) remains a vague area of investigation. We studied the inorganic phosphorus homeostasis during the first hour of an HD session.
  
  
  METHODS
  Twelve patients were studied twice, in two consecutive HD sessions. Total (TPR), extracellular (EPR), and intracellular (IPR) phosphorus mass removal was determined using the direct dialysate quantification (DDQ) method. Alterations of serum inorganic phosphorus (sP), erythrocyte intracellular phosphorus (P(ERY)), and 2,3-diphosphoglycerate (2,3-DPG) concentrations were measured before HD initiation and at 1, 2, 3, 4, 5, 10, 30, and 60 min.
  
  
  RESULTS
  The contribution of IPR to TPR was negative in the first 10 min of both HD sessions (-27.2 ± 6.5 and -26.4 ± 58 mmol, respectively, p = ns) while the contribution of the IPR to TPR increased as the time elapsed. Intracellular phosphorus and 2,3-DPG remained almost unchanged during the 60 min of HD session.
  
  
  CONCLUSIONS
  Unchanged P(ERY) concentration during the first hour of an HD session does not reject the hypothesis of a simultaneous efflux and influx of phosphorus from/to intracellular compartment.
authors.affiliation: Division of Nephrology, Section of Internal Medicine, School of Medicine, University of Ioannina, Ioannina, Greece.
authors.forename: Konstantinos P
authors.initials: KP
authors.lastname: Katopodis
authors.forename: Evangelia C
authors.initials: EC
authors.lastname: Dounousi
authors.forename: Anna S
authors.initials: AS
authors.lastname: Challa
authors.forename: Ioanna A
authors.initials: IA
authors.lastname: Vlachou
authors.forename: Despina P
authors.initials: DP
authors.lastname: Karasavvidou
mesh_terms: D019794:2,3-Diphosphoglycerate / Q000097:blood; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D054559:Hyperphosphatemia / Q000097:blood* / Q000209:etiology; D007424:Intracellular Fluid / Q000378:metabolism; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood*; D010758:Phosphorus / Q000097:blood*; D006435:Renal Dialysis; D013997:Time Factors
chemical_list: D015415:Biomarkers; D010710:Phosphates; D019794:2,3-Diphosphoglycerate; D010758:Phosphorus