Low Lymphocyte Levels

Lymphocytes are an integral part of our immune system. These white blood cells are present in the blood and lymphatic system and organs of the immune system.

Lymphocytes, along with the other white blood cells that are found in the blood, act against microorganisms such as bacteria, virus and fungi (yeast) to nullify them and to protect the body from infectious diseases.

Lymphocytes are of many types and the organ where some of these mature also differs. They can be distinguished as large granular lymphocytes and small lymphocytes on the basis of their appearance.

Large granular ones are termed as natural killer cells. They are present in the body from birth. These blood cells guard the body against cancerous cells which may cause tumors and the cells infected by bacteria or viruses.

These white blood cell depend on the change in the level of a molecule found in the surface of the cells to distinguish between normal and infected cells. Interferon is a chemical substance (cytokine family) that activates the large granular lymphocytes and release cytotoxic granules to eliminate the diseased cells.

Lymphocytes are produced in the bone marrow, however, not all them mature there. Because of this fact, they are named differently. This is especially true for small lymphocytes which are of two types; T cells and B cells.

T cells (Thymus cells) are produced in the bone marrow and travel all the way to the thymus gland, that is present at the base of the neck, to mature. Natural killer cells and helper cells are the main types which make up almost 80 percent of the lymphocytes.

B cells are produced and mature in the bone marrow and constitutes approximately, 10 percent of lymphocytes in total. This pair of cell works in tandem to fight against microbes. B cells produces and uses a chemical substance called antibodies to mark pathogens and infected body cells.

On the other hand, T cells that detect presence of this marked target, get activated and tries to eliminate them. All these lymphocytes are distributed throughout the lymph nodes of the lymphatic system.

Of all the white blood cells, which are also called leukocytes, lymphocytes account for 25-33 percent. The normal count when converted to more understandable numbers, comes to 1,000-4,800 and 3,000-9,500 of lymphocytes per microliter of blood in adults and children respectively.

In Adults and Children: Low levels of lymphocytes in adults and children differs considerably. If, in adults, this count falls to 1,000 lymphocytes per microliter it is said to be low count. Whereas in children, a count below 3,000 is taken to be low and is a worrisome condition.

Now, it is easy to see that low lymphocyte levels lead to two interpretations. Low levels of lymphocytes (large granular) can lead to conditions such as cancer or an infection in a person. On the other hand, low levels of lymphocytes (T cell or B cells) can indicate a less threatening condition (than cancer) of infection. Of course, these conditions must be handled thoroughly and with every precaution under the guidance of qualified doctor.

The type of the lymphocyte that is found low in count helps a doctor in deducing few things which help him in arriving at the diagnosis of the disease and in planning treatment for it.

Low CD4+, CD8+ Lymphocyte Count
A low CD4+ lymphocyte count (CD4+, a type of helper cell), CD8+ lymphocyte count (Cytotoxic T Lymphocyte) or CD4/CD8 ratio reveals to a doctor the extent of the proliferation of the human immunodeficiency virus. Less the number of CD4+ lymphocytes, greater is the proliferation of the virus.

Low B cell Count
Low B cells count states that something is not right with thymus gland (where they mature) or the bone marrow which produce these cells. The low count may be due to decreased presence of bone marrow affecting the production. After further tests the doctor may find, not necessarily in every case, that it is because of bone cancer.

The condition of low lymphocyte count is termed as lymphocytopenia which can have many causes associated with it.

A list of causes includes:

• Lymphocytopenia can be due to the body's inability to produce enough lymphocytes which may happen because of some immune system diseases like lymphoma, leukemia, etc.

• Body produces enough of them, but a majority of them are abnormal and are destroyed leading to a shortage.
• They cannot pass through the spleen or lymph nodes into the blood and are trapped and localized.
• A person may even suffer from a combination or all the above conditions leading to lymphocytopenia.

Low level of lymphocytes, that can leave our immune system under-prepared to fight against infections, is a cause of worry to any person. This condition must be seen into and brought to a satisfactory result under medical guidance.