You may have a lymphocyte count that is higher than would normally be expected but have few, if any, symptoms. Your doctor must then decide if this is a harmless, temporary situation, as can occur after an illness, or if it represents something more serious, such as a blood cancer or a chronic infection. Before deciding if a lymphocyte count is "too high" or is a cause of concern, your doctor may need to perform other tests.

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

  • Infection (bacterial, viral, other)
  • Cancer of the blood or lymphatic system
  • 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. HIV/AIDS
  5. Mononucleosis
  6. Multiple myeloma
  7. Other viral infections
  8. Tuberculosis
  9. Vasculitis
  10. Whooping cough

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

Jul. 30, 2013