Eosinophil quantification from a Complete Blood Count (CBC) involves determining the absolute number of eosinophils present in a microliter (L) or liter (L) of blood. The process relies on the automated hematology analyzer within a clinical laboratory, which counts different types of white blood cells, including eosinophils. The instrument reports this count, typically expressed as cells/L or cells/L. For instance, a report might indicate an eosinophil count of 300 cells/L.
Accurate determination of eosinophil numbers is crucial for diagnosing and managing various medical conditions. Elevated eosinophil levels, known as eosinophilia, can indicate parasitic infections, allergic reactions, asthma, certain skin disorders, and some types of cancer. Conversely, low eosinophil counts (eosinopenia) can occur in conditions like Cushing’s syndrome or during acute infections. Monitoring eosinophil levels helps clinicians assess disease activity, guide treatment decisions, and evaluate treatment efficacy. Historically, manual counting methods were used, but automated analyzers have significantly improved accuracy and efficiency.