What is a T cell count?
A T cell count is a blood test that measures the number of T cells in your body. T cells are a type of white blood cell called lymphocytes.
These cells fight off diseases. The two categories oflymphocytesare T cells and B cells. The T cells respond to viral infections and boost immune function of other cells, while the B cells fight bacterial infections.
Your body sometimes has too many or too few T cells. This may be a sign that yourimmune systemisn’t functioning properly.
A T cell count may also be known as a thymus-derived lymphocyte count or a T lymphocyte count. If you’re being treated forHIV, this test may be known as aCD4 cell count. Some T cells contain a CD4 receptor. This receptor is where HIV attaches to the T cell.
Your doctor may order a T cell count if you’re having symptoms of animmunodeficiency disorder, such asHIV. Symptoms associated with other conditions, such asleukemiaor othercancers, may also prompt a T cell count.
The symptoms of an immunodeficiency disorder include:
- frequently recurring infections
- severe infections from bacteria or other organisms that don’t usually cause severe infections
- trouble recovering from illnesses
- infections that don’t respond to treatments
- recurringfungal infections, such asyeast infections
- recurringparasitic infections
A T cell count requires only a small sample of your blood. There’s little you need to do to prepare for it.
Before your test, be sure to tell your doctor about all the medications you’re taking. This includes any over-the-counter (OTC) and prescription medications or herbal supplements.
Certain medications can impact your T cell count, which will alter the results of your test. Your doctor may ask you to stop taking your medications for a little while, or they may change the dosage before your test.
Medications that may affect your T cell count include:
- chemotherapy drugs
- radiation therapy
- corticosteroids
- immunosuppressive drugs, such as anti-rejection drugs
矩形ent surgery orhighly stressful experiencescan also affect your T cell count. You should tell your doctor if any of these situations apply to you.
Remember, your doctor only needs a small sample of your blood to get a T cell count. This procedure is also known as a blood draw or venipuncture. You may have the test in a medical laboratory or a doctor’s office.
- A healthcare provider will begin by cleaning an area of skin on your arm or hand withantisepticto help prevent infection.
- They’ll tie an elastic band around your upper arm so that blood collects in your vein.
- Next, they’ll insert a sterile needle into your vein and draw blood into a tube. The amount of blood drawn depends on the number of tests that your doctor ordered. It should take no longer than a couple of minutes to collect the blood sample needed.
- You may feel some pain while having your blood drawn. This usually feels like a pricking or stinging sensation. You can help ease this pain by relaxing your arm.
- When the technician finishes drawing blood, they’ll remove the elastic band and the needle and apply a bandage to thepuncture wound. You should apply pressure to the wound tostop bleedingandprevent bruising.
You’ll be free to go about your day following the blood draw. Your sample will go to a laboratory, where technicians will count the number and type of white blood cells present.
There are very few risks associated with a T cell count. However, people with compromised immune systems often have this test. They may be at greater risk for developing an infection than the rest of the population.
其他可能的T细胞的风险测试包括:
- multiple puncture wounds if the technician has trouble finding a vein
- excessivebleeding
- lightheadednessorfainting
- hematoma, which is a collection of blood under the skin
- aninfectionat the puncture site
According toHIV.gov, a healthy T cell count should be between 500 and 1,600 T cells per cubic millimeter of blood (cells/mm3).
Low T cell count
A low T cell count is more common than a high T cell count. Low T cell counts usually indicate problems with your immune system orlymphnodes. Low T cell counts may be due to:
- viral infections, such asinfluenza
- aging
- immunodeficiency disorders
- exposure to radiation
- HIV and AIDS
- cancers that affect the blood or lymph nodes, such asWaldenstrom’s macroglobulinemia,leukemia, andHodgkin’s disease
- congenital T cell deficiency, in some rare cases
High T cell count
Less often, you might have a T cell count that’s higher than normal. A high T cell count can be due to:
- infectious mononucleosis, also known as mono or “the kissing disease”
- acute lymphocytic leukemia (ALL), a type of cancer that affects the WBCs
- multiple myeloma, a type of cancer that affects the plasma cells in bone marrow
- genetic disorders, such as in autoimmune lymphoproliferative syndrome
Your doctor will discuss any further tests you need for a diagnosis. They’ll also provide you with treatment options if your results are above or below this range.
Medications may be prescribed to increase your T cell count. No specific foods have been shown to increase the number of WBCs or T cells in the body. However, a healthy diet can help to boost theimmune systemoverall.
