What is the primary hematologic change in equine piroplasmosis?

What is the primary hematologic change in equine piroplasmosis?

• A. Hemolytic anemia
• B. Leukocytosis
• C. Thrombocytopenia
• D. Eosinophilia

Answer: (A)

In equine piroplasmosis, parasites live inside red blood cells and destroy them, so the main hematologic change is hemolytic anemia. The parasites cause rupture of infected erythrocytes and prompt removal of these cells by the spleen and other reticuloendothelial tissues, leading to a drop in circulating red blood cells and resulting anemia. Clinically this shows up as pallor, weakness, and possibly tachycardia; in more severe cases you may see signs related to intravascular hemolysis such as hemoglobinuria or icterus due to increased bilirubin from red cell breakdown. While inflammation can yield mild leukocytosis and there can be thrombocytopenia from various disease processes, these are not the defining hematologic feature of piroplasmosis. Eosinophilia is not typical. For confirmation, one would look for piroplasms inside red blood cells on a blood smear or use molecular tests like PCR.

In equine piroplasmosis, parasites live inside red blood cells and destroy them, so the main hematologic change is hemolytic anemia. The parasites cause rupture of infected erythrocytes and prompt removal of these cells by the spleen and other reticuloendothelial tissues, leading to a drop in circulating red blood cells and resulting anemia. Clinically this shows up as pallor, weakness, and possibly tachycardia; in more severe cases you may see signs related to intravascular hemolysis such as hemoglobinuria or icterus due to increased bilirubin from red cell breakdown. While inflammation can yield mild leukocytosis and there can be thrombocytopenia from various disease processes, these are not the defining hematologic feature of piroplasmosis. Eosinophilia is not typical. For confirmation, one would look for piroplasms inside red blood cells on a blood smear or use molecular tests like PCR.