• Horse;
  • Hypercoagulation;
  • Hyperfibrinolysis;
  • Neonate;
  • Sepsis;
  • Systemic inflammatory response syndrome

Background: Septicemia is associated with a systemic inflammatory response, hemostatic activation, and disseminated intravascular coagulopathy (DIC).

Hypothesis: Increased plasma d-dimer concentration occurs in septic neonates and can reliably detect sepsis or DIC, and predict death in ill neonatal foals.

Animals: 40 septic, 41 nonseptic hospitalized foals, and 22 healthy neonates.

Methods: Prospective observational clinical study. Blood samples were collected on admission, at 24–48 hours after admission, and at the time of discharge or euthanasia. Plasma d-dimer concentration, clotting times, antithrombin activity, and fibrinogen concentration were determined.

Results: On admission, d-dimer concentration values were significantly higher in septic foals (median, 25–75th percentiles; 568, 245–2013 ng/mL) compared with the nonseptic and healthy groups (386, 175–559 and 313, 152–495 ng/mL, respectively), and in septic foals at the age of 2–7 days compared with similar-age nonseptic foals. By means of samples taken at 24–48 hours of hospitalization and a cut-off value of > 2000 ng/mL, D dimer concentration was significantly associated with the diagnosis of septicemia (odds ratio [OR] = 19.6, 95% confidence interval [95% CI] 1.9–203) and death (OR = 8.7, 95% CI 1.8–43). Owing to a high false-positive prediction rate (71%), a normal d-dimer concentration is better at eliminating the diagnosis of sepsis than an increased d-dimer concentration at predicting sepsis. Fifty percent of septic foals had a diagnosis of DIC, but d-dimer concentration was not significantly associated with the diagnosis of DIC.

Conclusions and clinical importance: Septic foals showed a marked activation of coagulation and fibrinolytic systems and a high prevalence of DIC. Increased plasma d-dimer concentration is significantly associated with the diagnosis of sepsis.