In an 83-year-old patient with an infection, which laboratory finding would the nurse expect?

• A. Minimal leukocytosis
• B. Decreased platelet count
• C. Increased hemoglobin and hematocrit levels
• D. Decreased erythrocyte sedimentation rate (ESR)

Answer: (A)

Older adults often have a blunted leukocyte response to infection, so the white blood cell count may rise only slightly or stay near normal. That means minimal leukocytosis is the most likely laboratory finding in an elderly patient with an infection, reflecting this waning immune response rather than a robust rise in WBCs seen in younger individuals.

ESR tends to rise with infection, not decrease, so a decreased ESR wouldn’t fit. Hemoglobin and hematocrit are not expected to be increased during infection (they’re often normal or decreased with age-related anemia or dehydration). Platelets can be variable, but a decreased platelet count is not the typical response to infection and would raise concern for other issues such as DIC or thrombocytopenia.