title: Inconsistency of reported uremic toxin concentrations.
abstract: Discrepancies in reported uremic toxin concentrations were evaluated for 78 retention solutes. For this analysis, 378 publications were screened. Up to eight publications per toxin were retained. The highest and the lowest reported concentrations, as well as the median reported concentration were registered. The ratio between the highest and the lowest (H/L) concentrations and, for some solutes, also the ratio between the highest and the median (H/M) concentrations were calculated. The compounds were arbitrarily subdivided into three groups based on their H/L ratio: group A, H/L < 3 (n = 33); group B, 3 < H/L < 8.5 (n = 20); and group C, H/L > 8.5 (n = 25). Solutes of groups A and B showed a low to intermediate scatter, suggesting a homogeneity of reported data. Group C showed a more substantial scatter. For at least 10 compounds of group C, extremely divergent concentrations were registered (H/M > 5.5) using scatter plot analysis. For all solutes of groups A and B, the highest reported concentration could be used as a reference. For some solutes of group C and for the compounds showing a divergent scatter analysis, however, more refined directives should be followed.
authors.affiliation: The Nephrology Section, Department of Internal Medicine, University Hospital, Gent, Belgium.
authors.forename: Natalie
authors.initials: N
authors.lastname: Meert
authors.forename: Eva
authors.initials: E
authors.lastname: Schepers
authors.forename: Rita
authors.initials: R
authors.lastname: De Smet
authors.forename: Angel
authors.initials: A
authors.lastname: Argiles
authors.forename: Gerald
authors.initials: G
authors.lastname: Cohen
authors.forename: Reinhold
authors.initials: R
authors.lastname: Deppisch
authors.forename: Tilman
authors.initials: T
authors.lastname: Drüeke
authors.forename: Ziad
authors.initials: Z
authors.lastname: Massy
authors.forename: Goce
authors.initials: G
authors.lastname: Spasovski
authors.forename: Bernd
authors.initials: B
authors.lastname: Stegmayr
authors.forename: Walter
authors.initials: W
authors.lastname: Zidek
authors.forename: Joachim
authors.initials: J
authors.lastname: Jankowski
authors.forename: Raymond
authors.initials: R
authors.lastname: Vanholder
mesh_terms: D015415:Biomarkers / Q000097:blood; D006801:Humans; D014511:Uremia / Q000097:blood*
chemical_list: D015415:Biomarkers