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What Causes Lymphocytosis?

Lymphocytosis is a medical condition characterized by elevated amounts of lymphocytes, which are a type of white blood cell, in the body. There are three main types of lymphocytes: natural killer cells, T cells, and B cells. Each is important when it comes to defending the body from illness and disease. Therefore, lymphocytosis itself is not an illness. Rather, it is caused by an illness or other problem.

In order to be diagnosed with lymphocytosis, an adult must have a lymphocyte count over 4,000 per microliter. Typically, lymphocytosis does not have any symptoms, which means the only way to diagnosis it is to perform a blood test.

A variety of infections and diseases can cause lymphocytosis. Viral infections are the most common cause of lymphocytosis, with glandular fever being one of the main causes. Infection mononucleosis, also known simply as mono or glandular fever, generally affects adolescents and young adults and is spread through blood and saliva. Common systems include sore throat, fever, and fatigue.

Bacterial infections such as tuberculosis can also cause lymphocytosis. Tuberculosis is one of the most deadly modern day infectious diseases. It usually effects the lungs, though it may also effect the circulatory system, central nervous system, genitourinary system, lymphatic system, genitourinary system, and the bones and joints.

Blood diseases such as chronic lymphocytic leukemia and other forms of leukemia are also possible causes of lymphocytosis. All forms of leukemia are a type of cancer, though the cancer may be located either in the blood or in the bone marrow. These types of cancer are often identified after diagnosing lymphocytosis.

In order to cure lymphocytosis, it is necessary to address the underlying health issue that has caused it to develop in the first place. Curing or treating the underlying cause of lymphocytosis will decrease the body’s need to produce more lymphocytes in order to protect the body from the illness, disease, or infection. Treating the problem to the point where lymphocytosis is cured does not, however, necessarily mean the underlying cause is completely eradicated from the body.

Written by Shannon Kietzman