Which lab value is commonly used to screen for infection or inflammation?

Which lab value is commonly used to screen for infection or inflammation?

• A. Hemoglobin
• B. Platelet count
• C. Erythrocyte sedimentation rate
• D. White blood cell (WBC) count

Answer: (D)

White blood cell count serves as a frontline signal of the body's immune response. When infection or inflammation occurs, the immune system ramps up production and release of leukocytes, often raising the total WBC count. This makes it a quick, broadly useful screen: it’s fast, widely available, and sensitive to acute immune activity. The other values measure different things—hemoglobin looks at anemia, platelets can rise with inflammation but aren’t a direct infection screen, and ESR reflects inflammation more slowly and non-specifically. So the white blood cell count best fits as a common screening test for infection or inflammation.

White blood cell count serves as a frontline signal of the body's immune response. When infection or inflammation occurs, the immune system ramps up production and release of leukocytes, often raising the total WBC count. This makes it a quick, broadly useful screen: it’s fast, widely available, and sensitive to acute immune activity. The other values measure different things—hemoglobin looks at anemia, platelets can rise with inflammation but aren’t a direct infection screen, and ESR reflects inflammation more slowly and non-specifically. So the white blood cell count best fits as a common screening test for infection or inflammation.