From the Research
Elevated white blood cell (WBC) count after an embolic stroke is a common occurrence, but it is not entirely normal and can be associated with increased morbidity and mortality, as evidenced by a recent study published in 2023 1. This elevation typically occurs within the first 24 hours following a stroke and can persist for several days. The WBC count commonly rises to levels between 10,000-15,000 cells/μL, though it can sometimes go higher. This post-stroke leukocytosis is primarily due to the body's inflammatory response to brain tissue damage. When brain cells are injured during a stroke, they release inflammatory mediators that trigger the immune system, resulting in increased production and mobilization of white blood cells. Some key points to consider include:
- Elevated WBC levels are linked to a higher risk of new vascular events and mortality, as shown in a study published in 2023 1.
- The association between WBC levels and outcomes after acute ischemic stroke has been consistently demonstrated in multiple studies, including those published in 2014 2 and 2018 3.
- While leukocytosis is common after stroke, very high WBC counts may warrant investigation for other causes such as infection.
- Healthcare providers typically monitor WBC counts along with other inflammatory markers during stroke recovery to distinguish between expected inflammatory responses and potential complications. It's essential to note that the interpretation of WBC counts should be done in the context of the individual patient's clinical presentation and other laboratory results. In clinical practice, the focus should be on identifying the underlying cause of the elevated WBC count and managing it accordingly to improve patient outcomes. The most recent and highest-quality study, published in 2023 1, provides the strongest evidence for the association between elevated WBC counts and poor outcomes after embolic stroke.