Abstract: TH-PO406

Oxidative Stress after Intravenous Iron in Dialysis Patients – A Real Phenomenon or an In Vitro Artifact?

Session Information

Category: Nutrition, Inflammation, and Metabolism

  • 1401 Nutrition, Inflammation, Metabolism

Authors

  • Eiselt, Jaromir, Charles University, Faculty of Medicine in Pilsen, Pilsen, Czechia
  • Rajdl, Daniel, Charles Univversity, Faculty of Medicine in Pilsen, Pilsen, Czechia
  • Kielberger, Lukas, Charles University, Faculty of Medicine in Pilsen, Pilsen, Czechia
  • Trefil, Ladislav, Charles Univversity, Faculty of Medicine in Pilsen, Pilsen, Czechia
Background

Intravenous iron can aggravate oxidative stress. However, the presence of the iron preparation in the serum sample may interfere with the determination of oxidative stress markers. The aim of the study was to measure markers of oxidative stress and serum iron after administration of i.v. iron.

Methods

A total of 10 patients on chronic hemodiafiltration (HDF) received in a random order physiological solution (CONTR), 200 mg of ferric carboxymaltose (FC) and 200 mg of iron succrose (IS). Infusions were given from min. 60 to min. 90 of 4 h HDF. In minutes 60, 90, 150 and 240 were measured thiobarbituric acid reacting substances (TBARS), 8-isoprostane (8-iso) and iron in serum. Iron was determined by a routine photometric method (Fe-PHOT) and by an atomic absorption spectrometry (Fe-AAS).

Results

We detected increase of TBARS after both FC and IS, while 8-iso rose only after administration of IS. Levels of serum iron were dramatically higher when using Fe-AAS, than Fe-PHOT. The Fe-AAS method, unlike Fe-PHOT, detects all plasmatic iron, including the one bound in iron-sugar complexes. Results are summarized in table. Changes in TBARS strongly correlated with serum iron measured by Fe-AAS after infusion of both IS (r=0.92, p<0.001) and FC (r=0.79, p<0.0001), but not after CONTR (r=0.23, p=0.133). On the other hand, 8-isoprostane did not correlate with Fe-AAS in any of the three tested treatments.

Conclusion

Immediate effect of i.v. administration of ferric carboxymaltose and iron succrose on oxidative stress of dialysis patients is probably small and difficult to prove with the respect to artifacts in analyses. Measurement of 8-isoprostane does not seem to be affected, compared to TBARS, by a false in vitro interference with intravenously administered iron-sugar complexes.

 Ferric carboxymaltoseIron succrosePhysiol. sol.P (AUC by ANOVA)
8-iso [ng.h/L]62 (57-68)a87 (79-99)b69 (52-86)<0.001
TBARS [µmol.h/L]4.0 (3.5-4.5)a,b3.1 (2.8-3.5)b2.2 (1.7-2.5)<0.001
Fe(PHOT) [µmol.h/L]73 (56-93)a,b139 (107-165)b27 (19-42)<0.001
Fe(AAS) [µmol.h/L]1984 (1704-2141)a,b1610 (1214-1729)b59 (44-70)<0.001

Values are medians (95 % CI) of serial measurements in serum; groups were compared using area under the curve (AUC) by ANOVA; Student-Newman-Keuls test was used for post-hoc pairwise comparisons; a P<0.05 vs. iron suc., b P<0.05 vs. physiol. sol.

Funding

  • Government Support - Non-U.S.