You may have a lymphocyte count that is higher than would normally be expected but have few, if any, symptoms. It's usually a harmless, temporary situation, as can occur after an illness. But it may represent something more serious, such as a blood cancer or a chronic infection. Your doctor may need to 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 may 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
  5. Mononucleosis
  6. Other viral infections
  7. Tuberculosis
  8. Vasculitis (blood vessel inflammation)
  9. Whooping cough

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

Jan. 11, 2018