A high white blood cell count usually indicates:

  • An increased production of white blood cells to fight an infection
  • A reaction to a drug that increases white blood cell production
  • A disease of bone marrow, causing abnormally high production of white blood cells
  • An immune system disorder that increases white blood cell production

Specific causes of a high white blood cell count include:

  1. Acute lymphocytic leukemia
  2. Acute myelogenous leukemia (AML)
  3. Allergy, especially severe allergic reactions
  4. Chronic lymphocytic leukemia
  5. Chronic myelogenous leukemia
  6. Drugs, such as corticosteroids and epinephrine
  7. Infections, bacterial or viral
  8. Myelofibrosis
  9. Polycythemia vera
  10. Rheumatoid arthritis
  11. Smoking
  12. Stress, such as severe emotional or physical stress
  13. Tuberculosis
  14. Whooping cough

Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.

Dec. 17, 2015