What are the causes of elevated neutrophil (white blood cell) count, also known as neutrophilia?

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From the Guidelines

Elevated neutrophils are a symptom of an underlying condition, such as infection, inflammation, or stress, and treatment should focus on addressing the cause rather than the elevated neutrophil count itself. When considering the management of elevated neutrophils, it is crucial to understand that neutrophilia can be a response to various stimuli, including bacterial infections, which are a significant concern in patients with neutropenia, as highlighted in a study on the prevention and treatment of cancer-related infections 1. Key points to consider in the context of elevated neutrophils include:

  • The body's immune response: Neutrophils are a type of white blood cell that plays a critical role in fighting infections, particularly those caused by bacteria.
  • Underlying causes: These can range from infections (bacterial, viral, or fungal) to inflammatory conditions, physical or emotional stress, certain medications, and rarely, blood disorders or cancer.
  • Diagnostic approach: A healthcare provider may perform additional tests, such as a complete blood count with differential, blood cultures, or imaging studies, to determine the underlying cause of elevated neutrophils.
  • Treatment strategy: The focus should be on treating the underlying condition, which may involve antibiotics for bacterial infections, supportive care for viral infections, or management of inflammatory conditions and stress. Given the information from the study on cancer-related infections 1, it's essential to recognize that while elevated neutrophils indicate a response to an underlying issue, the management of neutropenia (low neutrophil count) involves understanding the risks of infection and the importance of the neutrophil count in determining these risks. However, in the context of elevated neutrophils, the primary concern is identifying and treating the cause, rather than the neutrophil count itself, to prevent potential complications and improve patient outcomes.

From the Research

Elevated Neutrophils: Causes and Associations

  • Neutrophilia refers to an increase in the number of circulating neutrophils in the peripheral blood, with common etiologies including infection, inflammatory conditions, myeloproliferative disorders, malignancies, endocrinopathies, drugs, and anemia 2
  • Certain conditions such as stress, exercise, smoking, obesity, and obstructive sleep apnea have been associated with chronic idiopathic neutrophilia (CIN) and may provide explanations for neutrophilia previously thought to be idiopathic 2
  • Neutrophils are immune cells with potent antimicrobial properties, and their activation can contribute to autoimmune and inflammatory disease 3

Neutrophil Count Reduction

  • Intravenous treatment with ceftriaxone is associated with a risk of reduced neutrophil count, and this reduction can be predicted by routine baseline blood indices 4
  • A multifactor linear regression model can be used to predict the reduction in neutrophil count based on baseline haematological and biochemical parameters 4

Neutrophils in Disease Prevention and Treatment

  • Ciprofloxacin with erythromycin is effective prophylaxis against Gram-negative bacteraemia in neutropenic patients, but may select for erythromycin-resistant viridans streptococci 5
  • Neutrophils play a crucial role in preventing or aggravating infections, cardiovascular events, and cancer, and understanding their biology is essential for developing new therapeutic strategies 6
  • Neutrophils can promote health by favoring tissue repair, and their basic biology informs the development of new therapeutic strategies 6

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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