Plasma iron concentrations and systemic inflammatory response syndrome in neonatal foals

Background: Sparse information regarding plasma iron concentration in neonatal foals and its utility as an inflammatory marker in this population has been published. Objectives: To determine the physiologic plasma iron concentration in neonatal foals. To assess its utility as an inflammatory marker to predict systemic inflammatory response syndrome (SIRS) and as a prognostic marker. Animals: Forty-seven ill neonatal foals admitted to a referral equine hospital were divided in 2 groups based on the SIRS criteria (24 SIRS and 23 non-SIRS). Two control groups of 43 hospital and 135 stud farm healthy neonatal foals were also included. Methods: Observational prospective study. Data were summarized by mean and its 95% confidence interval and absolute frequency and percentage for quantitative andqualitative variables. One-way ANOVA, ANCOVA (group and age effects) and Dunnett as posthoc analysis were used to compare plasma iron concentration among groups. Results: Neonatal foals with SIRS did not have had any statistically significant different plasma iron concentrations compared to non-SIRS (P =.56) and stud farm control group (P =.99), 172.8 μg/dL (95% CI; 126.0-219.6), 193.1 μg/dL (139.1-247.2), and 181.8 μg/dL (171.3-192.4), respectively. Plasma iron concentration had a large variability in healthy neonatal foals, and was negatively correlated with age in hospital controls (rho = −0.387) and sick neonatal foals (rho = −0.598) (P <.001). Conclusions and Clinical Importance: Plasma iron was not a useful marker of SIRS in neonatal foals and was not associated with outcome.