Lymphopenia, also known as lymphocytopenia, describes low lymphocyte counts. The severity varies significantly from case-to-case, and particularly low lymphocyte counts can have serious repercussions. Symptoms may also change depending on what type of lymphocyte is diminishing. Lymphopenia is usually the result of an underlying condition that has somehow hindered lymphocyte health.
Lymphocytes
To understand lymphopenia, it is necessary to first understand lymphocytes and their functions. A lymphocyte is a type of white blood cell that performs various functions in the immune system. There are threetypes of lymphocytes. Natural killer cells are part of the innate immune system and defend against tumors and viral infections. T cells and B cells are the major cellular parts of the adaptive immune response. B cells enable the antibody immune response while T cells are involved with cell-mediated immunity.
General Causes
Lymphopenia occurs because of three general causes:
- The body does not produce enough lymphocytes
- The body produces enough lymphocytes, but something destroys them
- The lymphocytes become stuck in the lymph nodes or spleen
A combination of these issues may also cause lymphopenia. Recognizing the general causes is essential because it is often unclear how an underlying cause directly triggers these issues.
Symptoms
Having a low lymphocyte count may not cause any noticeable signs or symptoms. Because of the importance of lymphocytes in the immune system, a person may find they get sick more often or easier. Additionally, certain infections may recur. Because an underlying condition usually triggers lymphopenia, they will likely eventually notice symptoms of that condition. Such symptoms include an enlarged spleen, skin abnormalities, and mouth ulcers.
Classification
In certain cases, it is helpful to classify lymphopenia by determining which type of lymphocyte is impacted. T lymphopenia — a low T cell count — can be seen in HIV or other viral infections, cancer, during radiation therapy, associated with steroid treatments or inherited disorders. B lymphopenia results from medications that suppress the immune system, certain cancers, or a disease that weakens the immune system. NK lymphopenia is rare and lacks research.
Specific Triggers
Lymphopenia causes fall into two categories: acquired and inherited. Acquired causes result in lymphopenia developed after birth. These include infectious diseases like HIV, autoimmune disorders like lupus, radiation, and chemotherapy, or cancer. Inherited causes include Wiskott-Aldrich syndrome, DiGeorge syndrome, or severe combined immunodeficiency disorder. A person is born with these conditions.
Risk Factors
Certain factors indicate a higher risk of developing lymphopenia. These include
- HIV, AIDS, or similar infectious diseases
- Autoimmune disorders
- Blood cancers or other blood conditions
- Undergoing certain surgeries, such as cardiac bypass
- History of alcoholism or excessive drinking
- History of genital ulcers
- Advanced age
- Undernutrition or poor diet
Diagnosis
The diagnosis of lymphopenia is based on lymphocyte count, which shows lower than normal levels for the patient’s age group. Doctors typically suspect lymphopenia if a patient presents with repeating or unusual infections. They may then order a complete blood count with differential, as well as a measurement of lymphocyte subpopulations. Some doctors will test immunoglobulin levels to evaluate antibody production. If there are recurring infections, medical practitioners often test for immunodeficiency regardless of the lymphopenia test results.
Screening and Prevention
It is impossible to prevent inherited lymphopenia, making management the main goal. With certain lifestyle changes, a person may be able to reduce their risk for acquired lymphopenia. Undernutrition is a major risk factor, so maintaining a healthy diet is the easiest way to prevent a low lymphocyte count.
Treatment
Not every person with lymphopenia needs treatment. When treatment is required, doctors target the underlying cause, such as the cancer or infection. Some people with lymphopenia require IV or subcutaneous immune globulin because they have chronic immunoglobulin G deficiency. Current research focuses on artificially increasing lymphocyte production. Some methods rely on blood and marrow stem cell transplants, while others are medication-based.
Outlook
Ultimately, lymphopenia is an extremely variable condition and its outlook often depends on its underlying cause. Many people have no symptoms or issues, while others may experience debilitating health problems stemming from the original condition. Individuals with lymphopenia should stay away from people who are sick and avoid large crowds. They should also practice proper hygiene, frequent handwashing, and regularly visit their doctor.