Serum Iron and Plasma Fibrinogen Concentrations as Indicators of Systemic Inflammatory Diseases in Horses

Abstract

Detection of systemic inflammation, which is important for proper diagnosis and prompt treatment, can be challenging. Measurement of plasma iron concentration is a sensitive method for detecting systemic inflammation in horses compared with measurements of plasma fibrinogen concentration, a traditional marker for inflammation in the horse. Ninety-seven horses hospitalized with diseases causing systemic inflammation, 22 horses with localized inflammation, and 12 clinically normal horses were included in this study. A retrospective study was made on hospitalized horses that had both plasma iron and fibrinogen concentrations measured on hospital admission. Plasma iron concentration was lower in horses with systemic inflammation (64 +/- 45 microg/dL) than the reference interval minimum (105 microg/dL) and were significantly lower (P = .001) than the value in a group of horses with local inflammation (123 +/- 45 microg/dL) and in healthy transported horses (143 +/- 29 microg/dL). Low plasma iron and high fibrinogen concentrations were both sensitive indicators of systemic inflammation in horses with sensitivity of 90 and 82%, respectively. There was a similar correlation between either continued decreases in iron concentration (Rsp of 0.239) or increases in fibrinogen concentration (Rsp of 0.280) during hospitalization and a worse prognosis. Measurement of plasma iron concentration better reflected acute inflammation than did fibrinogen concentration.