Blood test

High lymphocyte count in the blood

Blood test
High lymphocyte count in the blood
Last update: 23/02/2021

What is a high count of lymphocytes in the blood called?

  • Lymphocytosis

What is the normal count of lymphocytes in the blood?

If you need to know which are the lymphocytes reference ranges or you require more information about the role of lymphocytes in the blood you can visit: Normal lymphocytes count in the blood

What does a high count of lymphocytes in the blood mean?

Lymphocytosis is the increase in the total count of lymphocytes in the blood. Lymphocytes are a type of WBC (White Blood Cell).

The elevation of the total lymphocyte count is usually correlated to an increase in the percentage of lymphocytes. Lymphocyte % will be above the 40%. It is better to make the study with the total count of lymphocyte and not with the percentage.

A high lymphocyte count is usually due to an infection. The role of lymphocytes is to stop and remove foreign invaders such as bacteria, viruses and parasites. For that reason, there is a high count in the active phase of an infection.

The common causes of a lymphocytosis are:

  • Virus infection (mononucleosis, cytomegalovirus, viral hepatitis, etc.).
  • Bacterial infection (whooping cough, brucellosis, syphilis, etc.).

In elderly people, a lymphocytosis with no sign of infection may be due to leukemia (chronic lymphocytic leukemia or acute lymphoblastic leukemia). In children, it may be due to viral infection (rubella, mumps, chickenpox, measles, etc.).

Lymphocytosis or a high lymphocyte count in the blood means:

  • Mild lymphocytosis (4 - 6 x 103/µl in adults):

    Lymphocyte count is a bit higher than normal. In middle-age people under 40 years old, the most common cause is a viral infection. The values will return to normal range in a few weeks.

    A mid lymphocytosis with swollen lymph nodes and fatigue may be a sign mononucleosis or cytomegalovirus infection.

    In children, it may be a consequence of suffering from mumps, chickenpox or other viral infections.

    In elderly people (over 55 years old), if there is anemia (hemoglobin low), thrombocytopenia (low platelet count) or neutropenia (low neutrophil count) it may be a sign of malignant cancer such as a lymphocytic leukemia.

  • Moderate lymphocytosis (6 - 20 x 103/µl in adults):

    A moderate lymphocytosis may be due to:

    • In children it is necessary to study a possible whooping cough, a bacterial infection.
    • In young people (under 40 years old) a moderate lymphocytosis after a week or more may be a sign of mononucleosis or cytomegalovirus infection.
    • In elderly people (over 50 years old) it is necessary to study a possible lymphocytic leukemia.

    In any case, a visit to your doctor is recommended. He will study your case and he will give you an appropriate diagnosis.

  • Severe lymphocytosis (> 20 x 103/µl in adults):

    A severe lymphocytosis is usually related to a leukemia (blood cancer) such as chronic or acute lymphoblastic leukemia). A lymphocyte count above 100 is a possibility in this type of leukemia but such a high value it does not seem to be related to the severity of the disease.

    There is also a disease called acute infectious lymphocytosis that runs with a severe lymphocytosis (between 40 and 80) but with a good prognosis.

Which factors can increase the lymphocyte count in the blood?

There are some health circumstances or drugs than can raise your lymphocyte count:

  • Vigorous exercise
  • Stress
  • Tobacco
  • Drugs
    • Antiasthmatic drugs
      • Isoprenaline
      • Salbutamol
    • Antibiotics
      • Cephalosporin
      • Minocycline
    • Antiepileptic drugs
      • Valproate
      • Carbamazepine
      • Phenytoin
      • Phenobarbital
      • Lamotrigine
    • Antifungal
      • Griseofulvin
    • Antipsychotics
      • Haloperidol
    • Antituberculars
      • 4-Aminosalicylic acid
    • Catecholamine
      • Epinephrine
    • L-DOPA
    • Niacinamide
    • Opiate
      • Morphine
    • Uricosuric
      • Allopurinol

Which diseases can increase your lymphocyte count in the blood?

A lymphocyte count higher than normal may be a sign of the following diseases:

  • Mononucleosis
  • Cytomegalovirus
  • Whooping cough
  • Viral hepatitis
  • Brucellosis
  • Mumps
  • Varicella
  • Measles
  • Rubella
  • Syphilis
  • Toxoplasmosis
  • Rickettsiosis
  • Tuberculosis
  • Herpes
  • Chronic lymphocytic leukemia
  • Acute lymphoblastic leukemia
  • Acute infectious lymphocytosis
  • Heavy chain disease
  • Thyrotoxicosis
  • Cat-scratch disease
  • Hyperthyroidism
  • Hypothyroidism
  • Addison's disease

What can I do to lower the lymphocyte count in the blood?

A high lymphocyte count is usually due to a viral or bacterial infection. For that reason, the best way to reduce the lymphocyte count is to treat the underlying infection.

Tobacco may increase the lymphocyte count. In case you are a smoker, it is advisable to give up smoking.

Where can I find more information about lymphocyte count in the blood?

You can visit our pages about:

Which values are considered a high lymphocyte count in the blood?

The following values are considered to be above the normal range:

IMPORTANT: These levels are expressed in number of thousands/µl (microliter). They are an example of a healthy white woman of about 45 years old with no known disease and not taking any medication. The ranges can be different depending on the laboratory or on your personal circumstances.

Mild lymphocytosis
4.1 x103/µl4.2 x103/µl4.3 x103/µl4.4 x103/µl4.5 x103/µl4.6 x103/µl4.7 x103/µl4.8 x103/µl
4.9 x103/µl5 x103/µl5.1 x103/µl5.2 x103/µl5.3 x103/µl5.4 x103/µl5.5 x103/µl5.6 x103/µl
5.7 x103/µl5.8 x103/µl5.9 x103/µl6 x103/µl    
Moderate lymphocytosis
6.1 x103/µl6.2 x103/µl6.3 x103/µl6.4 x103/µl6.5 x103/µl6.6 x103/µl6.7 x103/µl6.8 x103/µl
6.9 x103/µl7 x103/µl7.1 x103/µl7.2 x103/µl7.3 x103/µl7.4 x103/µl7.5 x103/µl7.6 x103/µl
7.7 x103/µl7.8 x103/µl7.9 x103/µl8 x103/µl8.1 x103/µl8.2 x103/µl8.3 x103/µl8.4 x103/µl
8.5 x103/µl8.6 x103/µl8.7 x103/µl8.8 x103/µl8.9 x103/µl9 x103/µl9.1 x103/µl9.2 x103/µl
9.3 x103/µl9.4 x103/µl9.5 x103/µl9.6 x103/µl9.7 x103/µl9.8 x103/µl9.9 x103/µl10 x103/µl
10.1 x103/µl10.2 x103/µl10.3 x103/µl10.4 x103/µl10.5 x103/µl10.6 x103/µl10.7 x103/µl10.8 x103/µl
10.9 x103/µl11 x103/µl11.1 x103/µl11.2 x103/µl11.3 x103/µl11.4 x103/µl11.5 x103/µl11.6 x103/µl
11.7 x103/µl11.8 x103/µl11.9 x103/µl12 x103/µl12.1 x103/µl12.2 x103/µl12.3 x103/µl12.4 x103/µl
12.5 x103/µl12.6 x103/µl12.7 x103/µl12.8 x103/µl12.9 x103/µl13 x103/µl13.1 x103/µl13.2 x103/µl
13.3 x103/µl13.4 x103/µl13.5 x103/µl13.6 x103/µl13.7 x103/µl13.8 x103/µl13.9 x103/µl14 x103/µl
14.1 x103/µl14.2 x103/µl14.3 x103/µl14.4 x103/µl14.5 x103/µl14.6 x103/µl14.7 x103/µl14.8 x103/µl
14.9 x103/µl15 x103/µl15.1 x103/µl15.2 x103/µl15.3 x103/µl15.4 x103/µl15.5 x103/µl15.6 x103/µl
15.7 x103/µl15.8 x103/µl15.9 x103/µl16 x103/µl16.1 x103/µl16.2 x103/µl16.3 x103/µl16.4 x103/µl
16.5 x103/µl16.6 x103/µl16.7 x103/µl16.8 x103/µl16.9 x103/µl17 x103/µl17.1 x103/µl17.2 x103/µl
17.3 x103/µl17.4 x103/µl17.5 x103/µl17.6 x103/µl17.7 x103/µl17.8 x103/µl17.9 x103/µl18 x103/µl
18.1 x103/µl18.2 x103/µl18.3 x103/µl18.4 x103/µl18.5 x103/µl18.6 x103/µl18.7 x103/µl18.8 x103/µl
18.9 x103/µl19 x103/µl19.1 x103/µl19.2 x103/µl19.3 x103/µl19.4 x103/µl19.5 x103/µl19.6 x103/µl
19.7 x103/µl19.8 x103/µl19.9 x103/µl20 x103/µl    
Severe lymphocytosis
20.1 x103/µl20.2 x103/µl20.3 x103/µl20.4 x103/µl20.5 x103/µl20.6 x103/µl20.7 x103/µl20.8 x103/µl
20.9 x103/µl21 x103/µl21.1 x103/µl21.2 x103/µl21.3 x103/µl21.4 x103/µl21.5 x103/µl21.6 x103/µl
21.7 x103/µl21.8 x103/µl21.9 x103/µl22 x103/µl22.1 x103/µl22.2 x103/µl22.3 x103/µl22.4 x103/µl
22.5 x103/µl22.6 x103/µl22.7 x103/µl22.8 x103/µl22.9 x103/µl23 x103/µl23.1 x103/µl23.2 x103/µl
23.3 x103/µl23.4 x103/µl23.5 x103/µl23.6 x103/µl23.7 x103/µl23.8 x103/µl23.9 x103/µl24 x103/µl
24.1 x103/µl24.2 x103/µl24.3 x103/µl24.4 x103/µl24.5 x103/µl24.6 x103/µl24.7 x103/µl24.8 x103/µl
24.9 x103/µl25 x103/µl25.1 x103/µl25.2 x103/µl25.3 x103/µl25.4 x103/µl25.5 x103/µl25.6 x103/µl
25.7 x103/µl25.8 x103/µl25.9 x103/µl26 x103/µl26.1 x103/µl26.2 x103/µl26.3 x103/µl26.4 x103/µl
26.5 x103/µl26.6 x103/µl26.7 x103/µl26.8 x103/µl26.9 x103/µl27 x103/µl27.1 x103/µl27.2 x103/µl
27.3 x103/µl27.4 x103/µl27.5 x103/µl27.6 x103/µl27.7 x103/µl27.8 x103/µl27.9 x103/µl28 x103/µl
28.1 x103/µl28.2 x103/µl28.3 x103/µl28.4 x103/µl28.5 x103/µl28.6 x103/µl28.7 x103/µl28.8 x103/µl
28.9 x103/µl29 x103/µl29.1 x103/µl29.2 x103/µl29.3 x103/µl29.4 x103/µl29.5 x103/µl29.6 x103/µl
29.7 x103/µl29.8 x103/µl29.9 x103/µl30 x103/µl30.1 x103/µl30.2 x103/µl30.3 x103/µl30.4 x103/µl
30.5 x103/µl30.6 x103/µl30.7 x103/µl30.8 x103/µl30.9 x103/µl31 x103/µl31.1 x103/µl31.2 x103/µl
31.3 x103/µl31.4 x103/µl31.5 x103/µl31.6 x103/µl31.7 x103/µl31.8 x103/µl31.9 x103/µl32 x103/µl
32.1 x103/µl32.2 x103/µl32.3 x103/µl32.4 x103/µl32.5 x103/µl32.6 x103/µl32.7 x103/µl32.8 x103/µl
32.9 x103/µl33 x103/µl33.1 x103/µl33.2 x103/µl33.3 x103/µl33.4 x103/µl33.5 x103/µl33.6 x103/µl
33.7 x103/µl33.8 x103/µl33.9 x103/µl34 x103/µl34.1 x103/µl34.2 x103/µl34.3 x103/µl34.4 x103/µl
34.5 x103/µl34.6 x103/µl34.7 x103/µl34.8 x103/µl34.9 x103/µl35 x103/µl35.1 x103/µl35.2 x103/µl
35.3 x103/µl35.4 x103/µl35.5 x103/µl35.6 x103/µl35.7 x103/µl35.8 x103/µl35.9 x103/µl36 x103/µl
36.1 x103/µl36.2 x103/µl36.3 x103/µl36.4 x103/µl36.5 x103/µl36.6 x103/µl36.7 x103/µl36.8 x103/µl
36.9 x103/µl37 x103/µl37.1 x103/µl37.2 x103/µl37.3 x103/µl37.4 x103/µl37.5 x103/µl37.6 x103/µl
37.7 x103/µl37.8 x103/µl37.9 x103/µl38 x103/µl38.1 x103/µl38.2 x103/µl38.3 x103/µl38.4 x103/µl
38.5 x103/µl38.6 x103/µl38.7 x103/µl38.8 x103/µl38.9 x103/µl39 x103/µl39.1 x103/µl39.2 x103/µl
39.3 x103/µl39.4 x103/µl39.5 x103/µl39.6 x103/µl39.7 x103/µl39.8 x103/µl39.9 x103/µl40 x103/µl
40.1 x103/µl40.2 x103/µl40.3 x103/µl40.4 x103/µl40.5 x103/µl40.6 x103/µl40.7 x103/µl40.8 x103/µl
40.9 x103/µl41 x103/µl41.1 x103/µl41.2 x103/µl41.3 x103/µl41.4 x103/µl41.5 x103/µl41.6 x103/µl
41.7 x103/µl41.8 x103/µl41.9 x103/µl42 x103/µl42.1 x103/µl42.2 x103/µl42.3 x103/µl42.4 x103/µl
42.5 x103/µl42.6 x103/µl42.7 x103/µl42.8 x103/µl42.9 x103/µl43 x103/µl43.1 x103/µl43.2 x103/µl
43.3 x103/µl43.4 x103/µl43.5 x103/µl43.6 x103/µl43.7 x103/µl43.8 x103/µl43.9 x103/µl44 x103/µl
44.1 x103/µl44.2 x103/µl44.3 x103/µl44.4 x103/µl44.5 x103/µl44.6 x103/µl44.7 x103/µl44.8 x103/µl
44.9 x103/µl45 x103/µl45.1 x103/µl45.2 x103/µl45.3 x103/µl45.4 x103/µl45.5 x103/µl45.6 x103/µl
45.7 x103/µl45.8 x103/µl45.9 x103/µl46 x103/µl46.1 x103/µl46.2 x103/µl46.3 x103/µl46.4 x103/µl
46.5 x103/µl46.6 x103/µl46.7 x103/µl46.8 x103/µl46.9 x103/µl47 x103/µl47.1 x103/µl47.2 x103/µl
47.3 x103/µl47.4 x103/µl47.5 x103/µl47.6 x103/µl47.7 x103/µl47.8 x103/µl47.9 x103/µl48 x103/µl
48.1 x103/µl48.2 x103/µl48.3 x103/µl48.4 x103/µl48.5 x103/µl48.6 x103/µl48.7 x103/µl48.8 x103/µl
48.9 x103/µl49 x103/µl49.1 x103/µl49.2 x103/µl49.3 x103/µl49.4 x103/µl49.5 x103/µl49.6 x103/µl
49.7 x103/µl49.8 x103/µl49.9 x103/µl50 x103/µl50.1 x103/µl50.2 x103/µl50.3 x103/µl50.4 x103/µl
50.5 x103/µl50.6 x103/µl50.7 x103/µl50.8 x103/µl50.9 x103/µl51 x103/µl51.1 x103/µl51.2 x103/µl
51.3 x103/µl51.4 x103/µl51.5 x103/µl51.6 x103/µl51.7 x103/µl51.8 x103/µl51.9 x103/µl52 x103/µl
52.1 x103/µl52.2 x103/µl52.3 x103/µl52.4 x103/µl52.5 x103/µl52.6 x103/µl52.7 x103/µl52.8 x103/µl
52.9 x103/µl53 x103/µl53.1 x103/µl53.2 x103/µl53.3 x103/µl53.4 x103/µl53.5 x103/µl53.6 x103/µl
53.7 x103/µl53.8 x103/µl53.9 x103/µl54 x103/µl54.1 x103/µl54.2 x103/µl54.3 x103/µl54.4 x103/µl
54.5 x103/µl54.6 x103/µl54.7 x103/µl54.8 x103/µl54.9 x103/µl55 x103/µl55.1 x103/µl55.2 x103/µl
55.3 x103/µl55.4 x103/µl55.5 x103/µl55.6 x103/µl55.7 x103/µl55.8 x103/µl55.9 x103/µl56 x103/µl
56.1 x103/µl56.2 x103/µl56.3 x103/µl56.4 x103/µl56.5 x103/µl56.6 x103/µl56.7 x103/µl56.8 x103/µl
56.9 x103/µl57 x103/µl57.1 x103/µl57.2 x103/µl57.3 x103/µl57.4 x103/µl57.5 x103/µl57.6 x103/µl
Medically reviewed by our Medical staff on 23/02/2021


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