title: Ultradian variation in serum phosphate concentration in patients on haemodialysis.
abstract: To study how much the serum phosphate concentration could vary on the day before scheduled dialysis we obtained 24-37 timed measurements during 24 h in nine patients on maintenance haemodialysis. During the observation there was an increase in serum phosphate concentration of 0.239 +/- 0.022, P < 0.01). Surprisingly six of the nine patients exhibited nine statistically and clinically significant nadirs with decrements of 0.21 +/- 0.04 mmol/l against an intra-assay standard deviation of about 0.05 mmol/l. Five of the nadirs occurred at 11.40-14.50, mean 12.59, and three at 19.00-21.30, mean 20.00. We found no coinciding changes in the serum calcium concentration. These findings indicate that serum phosphate concentrations do not always reflect phosphorus balance or intake.
authors.affiliation: Medical Department C, Aalborg Hospital Syd, Denmark.
authors.forename: T
authors.initials: T
authors.lastname: Ring
authors.forename: A K
authors.initials: AK
authors.lastname: Sanden
authors.forename: H H
authors.initials: HH
authors.lastname: Hansen
authors.forename: P
authors.initials: P
authors.lastname: Halkier
authors.forename: C
authors.initials: C
authors.lastname: Nielsen
authors.forename: L
authors.initials: L
authors.lastname: Fog
mesh_terms: D000204:Activity Cycles / Q000502:physiology*; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood*; D006435:Renal Dialysis
chemical_list: D010710:Phosphates