White blood cells are made in bone marrow — the spongy tissue inside some of the larger bones. Conditions that affect the bone marrow are the usual causes of low white blood cell count. Some of these conditions are present at birth, also known as congenital.

Causes of a low white blood cell count include:

  1. Aplastic anemia
  2. Chemotherapy
  3. Radiation therapy
  4. Epstein-Barr virus
  5. Hepatitis A
  6. Hepatitis B
  8. Infections
  9. Leukemia
  10. Lupus
  11. Rheumatoid arthritis
  12. Malaria
  13. Malnutrition and lack of certain vitamins
  14. Medications, such as antibiotics
  15. Sarcoidosis
  16. Sepsis (an overwhelming bloodstream infection)
  17. Tuberculosis

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

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Dec. 10, 2022