Fundamentals of Nursing Q 280
Which of the following white blood cell (WBC) counts clearly indicates leukocytosis?
A. 4,500/mm³
B. 7,000/mm³
C. 10,000/mm³
D. 25,000/mm³
Correct Answer: D. 25,000/mm³
Leukocytosis is any transient increase in the number of white blood cells (leukocytes) in the blood. The normal number of WBCs in the blood is 4,500 to 11,000 WBCs per microliter (4.5 to 11.0 × 109/L). Normal value ranges may vary slightly among different labs. Thus, a count of 25,000/mm3 indicates leukocytosis.
Option A: A WBC count is a blood test to measure the number of white blood cells (WBCs) in the blood. WBCs are also called leukocytes. They help fight infections. A higher than normal WBC count is called leukocytosis. Leukocytosis is the broad term for an elevated white blood cell (WBC) count, typically above 11.0×10^9/L, on a peripheral blood smear collection. The exact value of WBC elevation can vary slightly between laboratories depending on their ‘upper limits of normal’ as identified by their reference ranges.
Option B: The WBC value represents the sum-total of white blood cell subtypes, including neutrophils, eosinophils, lymphocytes, monocytes, atypical leukocytes that are not normally present on a peripheral blood smear (e.g., lymphoblasts), or any combination of these. The clinician should properly characterize the leukocytosis and determine if further evaluation and workup are indicated.
Option C: Leukocytosis can occur acutely and often transiently or chronically, either in response to an inflammatory stressor/cytokine cascade or as part of an autonomous myeloproliferative neoplasm. Neutrophilia is the most common presentation, but clinicians should be aware of the other cell lines that can be involved in acute and chronic presentations. A detailed history, physical examination, medication reconciliation, full evaluation of a CBC with differential, and comparison to prior CBCs can help clinicians elucidate the underlying cause of leukocytosis and guide appropriate treatment.