Mean platelet component as an indicator of platelet activation in foals and adult horses

Mean platelet component (MPC) is a new platelet variable, measured by modern commercial complete blood count analyzers, that is reduced during platelet activation in humans and small animals.

MPC decreases in horses with clinical conditions that cause platelet activation and disseminated intravascular coagulation (DIC).

We obtained 418 CBCs from 100 sick and 20 healthy neonates and 178 sick and 45 sound adult horses. Sick neonates were classified into septic and nonseptic, and DIC and non-DIC groups. Adults were grouped by diagnoses (systemic inflammatory disorders, gastrointestinal problems, and thrombocytopenia).

MPC together with platelet count, mean platelet volume, platelet distribution width, and platelet component distribution width were measured with a commercial analyzer and compared between the different disease and control groups in neonates and in adults.

MPC values were significantly lower in the septic and nonseptic neonates (24.0 +/- 3.5 g/dL and 26.6 +/- 2.6 g/dL, respectively) than in the control group (28.1 +/- 1.7 g/dL). Neonates with DIC had the lowest MPC values (23.8 +/- 6.3 g/dL). MPC values in adult horses were significantly lower in the inflammatory (23.5 +/- 4.7 g/dL), gastrointestinal obstruction (23.0 +/- 5.0 g/dL), enteritis (23.6 +/- 4.6 g/dL), ischemic (23.9 +/- 5.1 g/dL), and thrombocytopenia (20.2 +/- 5.7 g/dL) groups when compared with control horses (26.2 +/- 3.5 g/dL). Other platelet variables were not different between the control and the disease groups.

MPC might be a useful variable for quickly and easily detecting platelet activation in sick neonates and adult horses.