Elevated lymphocyte levels, known as lymphocytosis, usually indicate that your body is actively fighting an infection or dealing with another inflammatory condition. This means your immune system, specifically these white blood cells, is ramping up its activity to combat an invader that could make you sick.
Common Causes of High Lymphocytes
A higher-than-normal lymphocyte count can be caused by a variety of factors. Here are some of the most common:
-
Infections:
- Viral infections: Common viral infections like the flu (influenza), mononucleosis (mono), measles, chickenpox, and cytomegalovirus (CMV) can all cause lymphocytosis. These infections trigger the immune system to produce more lymphocytes to fight off the virus.
- Bacterial infections: Certain bacterial infections, such as whooping cough (pertussis) or tuberculosis, can also lead to an elevated lymphocyte count.
-
Inflammatory Conditions:
- Autoimmune diseases: Conditions like rheumatoid arthritis, lupus, and Crohn's disease, where the body's immune system mistakenly attacks its own tissues, can cause chronic inflammation and lead to increased lymphocyte production.
- Allergies: Severe allergic reactions can sometimes trigger a temporary increase in lymphocytes.
-
Certain Cancers:
- Leukemia: Some types of leukemia, particularly chronic lymphocytic leukemia (CLL), directly involve the abnormal production of lymphocytes.
- Lymphoma: Lymphomas, cancers of the lymphatic system, can also lead to increased lymphocyte counts.
-
Other Causes:
- Smoking: Chronic smoking can sometimes elevate lymphocyte levels.
- Stress: Severe stress, both physical and emotional, can temporarily increase lymphocyte counts.
- Splenectomy: Removal of the spleen can sometimes lead to lymphocytosis.
When to See a Doctor
While a slightly elevated lymphocyte count is often nothing to worry about, it's important to consult a doctor if:
- Your lymphocyte count is significantly elevated.
- You have other symptoms, such as fever, fatigue, unexplained weight loss, night sweats, or swollen lymph nodes.
- The elevated lymphocyte count persists for an extended period.
Diagnosis and Treatment
Your doctor will likely perform a physical exam and ask about your medical history and symptoms. They may also order additional tests, such as:
- Complete blood count (CBC): To confirm the lymphocytosis and assess other blood cell counts.
- Peripheral blood smear: To examine the lymphocytes under a microscope.
- Flow cytometry: To identify specific types of lymphocytes.
- Bone marrow biopsy: In some cases, a bone marrow biopsy may be necessary to rule out leukemia or lymphoma.
Treatment for lymphocytosis depends on the underlying cause. For example, bacterial infections are treated with antibiotics, while viral infections usually resolve on their own with rest and supportive care. Autoimmune diseases are managed with medications that suppress the immune system. Cancers may require chemotherapy, radiation therapy, or other treatments.
