From the Guidelines
Persistently elevated white blood cell (WBC) counts are most commonly caused by hematologic malignancies, such as leukemia, which can directly affect white blood cell production, as seen in chronic myeloid leukemia (CML) where WBC counts can be persistently elevated (> 10 x 10^9/L) unresponsive to therapy 1.
Causes of Elevated WBC Counts
The causes of persistently elevated WBC counts can be multifactorial, including:
- Chronic infections, such as tuberculosis, endocarditis, or osteomyelitis, which can trigger ongoing immune responses
- Inflammatory conditions like rheumatoid arthritis, inflammatory bowel disease, and vasculitis, which often present with elevated WBCs due to persistent inflammation
- Certain medications, including corticosteroids, lithium, and epinephrine, which can stimulate WBC production or release from bone marrow
- Hematologic malignancies, such as leukemia, lymphoma, and myeloproliferative disorders, which directly affect white blood cell production
- Physiological stress, smoking, obesity, and chronic stress, which can contribute to higher baseline WBC counts
- Genetic disorders, like hereditary leukocytosis, which may cause lifelong elevation
Evaluation and Treatment
When evaluating persistent leukocytosis, it's essential to consider the patient's complete clinical picture, including specific WBC subtypes affected (neutrophils, lymphocytes, etc.), as this often provides clues to the underlying cause 1. Treatment should target the underlying condition rather than the elevated count itself, as the leukocytosis is typically a symptom rather than a primary disorder. In cases of hematologic malignancies, such as CML, treatment with tyrosine kinase inhibitors (TKIs) can help reduce WBC counts and manage the disease 1. For other conditions, such as chronic infections or inflammatory disorders, treatment should focus on resolving the underlying cause of the elevated WBC count.
Risk Stratification
Patient stratification by risk is crucial in managing tumor lysis syndrome, which can occur in patients with high-risk cancers, such as Burkitt’s lymphoma or acute lymphoblastic leukemia (ALL) with a WBC count of 100,000 or higher 1. In these cases, prompt institution of definitive therapy and measures to rapidly reduce the WBC count, such as apheresis or hydroxyurea, are essential to prevent tumor lysis and organ dysfunction.
Conclusion is not allowed, so the response is ended here.
From the Research
Causes of Persistently Elevated WBCs
The causes of persistently elevated White Blood Cell (WBC) counts can be categorized into several groups, including:
- Malignant causes, such as leukemia 2, 3, 4
- Nonmalignant causes, such as:
- Infections, particularly bacterial 2, 3
- Inflammatory conditions, such as chronic inflammatory diseases 2
- Physical stress, such as surgery, exercise, trauma, and emotional stress 2, 3
- Medications, such as corticosteroids, lithium, and beta agonists 2, 3
- Other conditions, such as asplenia, smoking, and obesity 2
- Other potential causes, such as:
Malignant Causes
Malignant causes of elevated WBC counts include various types of leukemia, such as acute myeloid leukemia (AML) 4 and chronic leukemia 3. These conditions can lead to an overproduction of WBCs, resulting in elevated counts.
Nonmalignant Causes
Nonmalignant causes of elevated WBC counts are more common and can be caused by a variety of factors, including infections, inflammatory conditions, physical stress, and medications. For example, a study found that patients with sepsis, major trauma, and cerebrovascular accident had elevated WBC counts 5.
Diagnosis and Treatment
Diagnosis of the underlying cause of elevated WBC counts is crucial for effective treatment. A repeat complete blood count with peripheral smear may provide helpful information, such as types and maturity of WBCs, uniformity of WBCs, and toxic granulations 2. Treatment depends on the underlying cause and may include antibiotics, anti-inflammatory medications, and supportive care. In some cases, referral to a hematologist/oncologist may be necessary 2.