From the Guidelines
Hemolytic crisis in sickle cell disease patients is associated with an elevated white blood cell (WBC) count, which can range from 12,000 to 30,000 cells/μL or even higher due to the body's inflammatory response and other mechanisms. During a sickle cell crisis, the inflammatory response triggered by vaso-occlusion and tissue ischemia stimulates bone marrow to release more white blood cells 1. Additionally, the spleen, which normally filters and removes some white blood cells, may function poorly in sickle cell patients due to repeated infarction (autosplenectomy), contributing to higher circulating WBC levels. The body also responds to hemolysis by increasing white cell production as part of the systemic inflammatory response. Some key points to consider include:
- The elevation of WBC count is a common finding during hemolytic crisis in sickle cell disease patients
- Very high WBC levels may indicate concurrent infection, which requires careful evaluation since infection can both trigger and complicate sickle cell crises
- Clinicians should interpret elevated WBC counts in the context of other clinical findings to distinguish between crisis-related leukocytosis and infection. It's worth noting that while the study by 1 provides guidance on transfusion support for patients with sickle cell disease, the relationship between hemolytic crisis and WBC count elevation is well-established in the medical literature, and this association is a key consideration in the management of sickle cell disease patients.
From the Research
Hemolytic Crisis and White Blood Cell Count in Sickle Cell Disease
- Hemolytic crisis in sickle cell disease patients can lead to various complications, including acute anemia and organ failure 2.
- The relationship between hemolytic crisis and white blood cell (WBC) count is not directly addressed in the provided studies, but it is known that an abnormal leukocyte count is associated with a worse clinical picture in sickle cell disease 3.
- Elevated leukocyte counts can contribute to vaso-occlusion and worsen clinical manifestations in sickle cell patients, including clinical stroke, acute chest syndrome, end organ damage, and infarction pain 3.
- Hydroxyurea therapy has been shown to inhibit the recruitment and invasion of neutrophils, which can help lower vaso-occlusion and improve outcomes in sickle cell patients 3.
- There is no direct evidence in the provided studies to suggest that hemolytic crisis specifically elevates WBC count, but it is clear that an abnormal leukocyte count plays a significant role in the pathophysiology of sickle cell disease 3.
Sickle Cell Disease and Blood Transfusions
- Blood transfusions are sometimes necessary in sickle cell disease patients, particularly in cases of acute hemolytic, aplastic, or sequestration crises 4.
- Hemolytic transfusion reactions are a rare but serious complication of blood transfusion in sickle cell disease patients, and can be difficult to diagnose 5, 6.
- Alloimmunization against red blood cell antigens is a major trigger of hemolytic transfusion reactions, but abnormal complement activation and the underlying condition of chronic hemolysis can also contribute to the reaction 5.