Low Lymphocyte Count: Causes, Symptoms and Normal Ranges

Symptoms and Causes of Low Lymphocyte Count and Normal Ranges

Low lymphocyte count (Lymphocytopenia) could indicate that you are at greater risk of developing infections because your lymphocytes are low. Lymphocytes are a type of white blood cells and they are essential to kill off bacteria and viruses and prevent infections from getting worse. A weakened immune system is often caused by a low number of lymphocytes and other types of white blood cells.

There are 3 types of Lymphocytes in your blood

  1. B lymphocytes (B-cells)
  2. T lymphocytes (T-cells)
  3. Natural Killer Cells (NK cells)

Together they help to keep you healthy and free of infection. The normal lymphocyte count range is between 1000 and 4800 per microliter of blood and it will take up about 20% to 40% of your total white blood cell count.

A low level of lymphocytes in the blood can be caused by various factors. For example, nutrient deficiencies, stress, and fasting can all cause your lymphocyte count to drop. If blood tests show a significant drop in the number of lymphocytes then doctors will check for certain diseases like viral infections, autoimmune and inflammatory conditions, or certain cancers.

In many cases, enjoying a healthy diet with plenty of protein, vitamins, and minerals, getting enough rest, and addressing any nutrient deficiencies can help keep your lymphocyte levels normal. However, if doctors suspect a more serious cause of decreased levels of lymphocytes, you will have to treat the underlying medical conditions to get your lymphocyte levels back to normal.

What is Normal Lymphocytes Range?

Low lymphocyte count - Normal Lymphocytes
Low lymphocyte count

In order to check for low lymphocytes in a blood test, doctors will perform a differential blood test to count the number of lymphocytes. If your lymphocyte count is less than 1000/μL then you have lymphocytopenia (low lymphocyte count). Lymphocytopenia can only be found by using differential blood test results that count the number of T-cells and B-cells. In some cases, total white blood count can seem normal even when there is a low lymphocyte count.

What does Low Lymphocytes in Blood Test Mean?

Each type of lymphocyte plays its own role in keeping your immune system strong and your body healthy. A decrease in the number of lymphocyte T-cells and natural killer (NK) cells will mean that it is harder to control certain viral, fungal, and parasitic infections. NK cells also have the ability to identify and kill cancer cells without having to learn that they are abnormal.

Stress: It is known that stress can weaken the immune system and cause you to get more infections.

Fasting: One reason your blood test could show up that you have low lymphocytes is if you have been fasting or been on an extreme diet.

Zinc deficiency: A low lymphocyte count could mean that you have a zinc deficiency. Zinc is an important mineral that is needed for a healthy immune system.

Aplastic anemia: A rare type of anemia can cause a deficiency in white blood cells, red blood cells, and platelets.

Autoimmune disorders: Some autoimmune disorders can affect your T-cells and B-cells causing a drop in lymphocyte count.

AIDS: One of the most common reasons for severe, chronic low levels of lymphocytes is AIDS.

Certain cancers: Cancer can also affect lymphocyte count and cause lymphocytopenia. This can be due to cancer itself or because of chemotherapy or radiation treatment to destroy cancer cells.

How to Treat Low Lymphocytes

To treat low levels of lymphocytes that show up in a blood test, doctors will treat the underlying disorder or infection. This may mean using drugs to kill off serious viral or bacterial infections or treating cancer.
At the same time, doctors will monitor your red blood cell and white blood cell levels to check how any treatments are working.

Natural Ways to Increase Lymphocytes

In many cases, you can prevent acute cases of lymphocytopenia by looking after your health and enjoying a well-balanced diet. Here are some ways to keep your blood healthy and give your immune system a boost to improve your lymphocyte count.

  • Consume enough protein
  • Green tea
  • Turmeric
  • Vitamin A and D
  • Vitamin B6 to prevent low lymphocyte count
  • Get enough zinc
  • Get enough sleep

What happens if lymphocyte count is too high?

If your lymphocyte count is excessively higher than normal levels, then you could have a condition called lymphocytosis.
In some cases, serious conditions like chronic infections or cancer can be a cause of lymphocytosis. Your doctor will check your blood work to monitor levels of white blood cells to help diagnose the reason.

Is more than 3000 lymphocytes (<45%) considered as ‘high’?

If you are an adult, and have more than 3000 lymphocytes (<40%) in one micro-liter of blood, then it is already considered a high lymphocyte count, also known as lymphocytosis. You should know that a low lymphocyte count can also entail consequences, so we advise you to check what is the normal range of lymphocyte count. In children, this threshold may vary with age, but can be as high as 7000 to 9000 lymphocytes in one micro-liter of blood. The exact measurements may even vary from one laboratory to the other.

You should know that there are two types of lymphocytosis:

Monoclonal lymphocytosis: Also known as MBL, the blood test will show a low level of for CLLs (>5000 per micro-liter of blood). Though it is not a genetic disorder, people over 40 years old may have a higher predisposition to it if it has run in the family and increases with age.

Polyclonal lymphocytosis: Also known as PPBL (persistent polyclonal lymphocytosis), will show a stable MBL, which is how it can be told apart from the latter. PPBL does not need to show such a high lymphocyte count as MBL either. Caucasian, young and smoking women are those with a higher risk factor.

When to See a Doctor

Low lymphocyte count-When to See a Doctor
Low lymphocyte count

Usually, a complete blood count test is the first time a person finds out that they have a low lymphocyte count. If doctors suspect an infection or other cause of low lymphocytes, then they will check for other symptoms.
However, there are some signs of low lymphocyte count that may indicate a serious health condition. Some of them include:

  • Enlarged lymph nodes in your armpit, neck, or top of your neck
  • A chronic cough or a runny nose that could indicate a respiratory viral infection
  • Swollen joints and a rash
  • Small tonsils
  • Suffering from recurring infections
Medically Reviewed By
Dr. Kaushal M. Bhavsar (MBBS, MD)Assistant Professor in Pulmonary Medicine, GMERS Medical College, Ahmedabad