You can have a higher than normal lymphocyte count but have few, if any, symptoms. It usually occurs after an illness and is harmless and temporary.

But it might represent something more serious, such as a blood cancer or a chronic infection. Your doctor might perform other tests to determine if your lymphocyte count is a cause for concern.

If your doctor determines that your lymphocyte count is high, the test result might be evidence of one of the following conditions:

  1. Infection (bacterial, viral, other)
  2. Cancer of the blood or lymphatic system
  3. An autoimmune disorder causing ongoing (chronic) inflammation

Specific causes of lymphocytosis include:

  1. Acute lymphocytic leukemia
  2. Chronic lymphocytic leukemia
  3. Cytomegalovirus (CMV) infection
  4. Hepatitis A
  5. Hepatitis B
  6. Hepatitis C
  7. HIV/AIDS
  8. Hypothyroidism (underactive thyroid)
  9. Lymphoma
  10. Mononucleosis
  11. Other viral infections
  12. Syphilis
  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.

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July 22, 2021