Leukocytes or white blood cells play an important role in helping the body fight infection or other diseases. A high leukocyte count can be caused by an infection, but it can also indicate certain diseases to watch out for, such as blood disorders or cancer.
Leukocytes or white blood cells are produced by the bone marrow and circulated throughout the body through the bloodstream. Leukocytes are an important part of the immune system that functions to produce antibodies that can fight viruses, fungi, bacteria, and disease-causing parasites that enter the body.
Normal Leukocyte Count
Newborns generally have a leukocyte count between 9,000–30,000 per microliter (mcL) of blood. This range of normal leukocyte counts will change with age to only 5,000–10,000 mcL in adulthood.
In adults, the white blood cell or leukocyte count is said to be high if it reaches more than 11,000 mcL.
Various Causes of High Leukocyte Count
There are five types of white blood cells or leukocytes, namely neutrophils, lymphocytes, monocytes, eosinophils, and basophils. When calculated by percentage, leukocytes are called normal if they consist of 40–60% neutrophils, 20–40% lymphocytes, 2–8% monocytes, 1–4% eosinophils, and 0.5%–1% basophils. However, sometimes the number of leukocytes can increase.
The following are some of the causes of high leukocytes based on the type of leukocyte:
1. Neutrophils
Neutrophils are the most abundant type of white blood cell in the body. Neutrophils can move freely through the walls of blood vessels and into body tissues to fight all bacteria, viruses, and parasites that cause infection.
Your neutrophil count may increase if you have any of the following conditions:
- Bacterial, viral, or fungal infection
- Injuries or injuries, for example during postoperative recovery
- Inflammation, for example in inflammatory bowel disease, rheumatoid arthritis, or rheumatic fever
- Blood cancer or leukemia
- Pregnancy, especially when the gestational age has reached the last trimester or before delivery
- Excessive stress or exercise
2. Lymphocytes
There are 2 types of leukocytes, namely B cell lymphocytes which are responsible for producing antibodies and T lymphocytes which play a role in recognizing and capturing foreign organisms or objects in the body.
A high leukocyte count can cause an increase in the number of lymphocytes. This condition can be caused by several things, such as:
- Viral infections, such as measles, smallpox, herpes, rubella, cytomegalovirus, and hantavirus
- Bacterial infections, such as whooping cough (pertussis) and tuberculosis
- Cancers, such as multiple myeloma, leukemia, and lymphoma.
- Glandular fever or mononucleosis
- Hepatitis due to viral or bacterial infection
3. Monocytes
Among other types of leukocytes, monocytes are the white blood cells with the largest size. This type of leukocyte plays a role in capturing and fighting bacteria, parasites, and fungi that enter the body.
An increased number of monocytes can be caused by several things, namely:
- Viral infections, such as measles, mumps, and mononucleosis
- Bacterial infections, such as tuberculosis, brucellosis, and syphilis
- Parasitic infections, such as worms and malaria
- Endocarditis
- Leukemia
- Hodgkin's disease
- Chronic inflammation, such as lupus, vasculitis, and rheumatoid arthritis
4. Eosinophils
Eosinophils are a type of leukocyte or white blood cell that functions to destroy viruses, bacteria, and parasites, and trigger an inflammatory response, such as in allergic reactions, eczema, and asthma.
A high eosinophil count can be caused by the following conditions:
- Worm infection
- Drug side effects
- Hypereosinophilia syndrome
- Celiac Disease
- Cancer
- Allergic reactions, such as eczema or asthma
- Autoimmune diseases, such as lupus, Crohn's disease, and ulcerative colitis
5. Basophils
Basophils are white blood cells that play a role in fighting worm parasites, stopping blood clotting, and producing allergic reactions. A high basophil count can be caused by:
- Hypothyroidism
- Myeloproliferative disease, which is a disease of the bone marrow
- Chronic inflammation, as in rheumatoid arthritis and ulcerative colitis
- Leukemia
- Recovery from spleen removal surgery or splenectomy
So, in conclusion, the number of white blood cells or leukocytes can increase when a person's body experiences the following conditions:
- Increased production of white blood cells to fight infection
- Immune system disorders that make white blood cell production increase
- Side effects of drugs that increase the production of white blood cells
- Bone marrow disease that causes the production of white blood cells to rise abnormally
Symptoms of High Leukocytes or Leukocytosis
High leukocytes or leukocytosis do not always cause symptoms. However, people with high WBCs may experience the following signs and symptoms:
- Fever
- Bleeding or easy bruising
- The body feels tired and weak
- Dizziness or headache
- Arm, leg, or stomach pain or tingling
- Difficulty breathing, concentrating, or impaired vision
- Losing weight for no reason
- No appetite
- Swollen lymph nodes
Because it can be caused by many diseases, high WBC is a condition that needs to be treated immediately. If you experience the above symptoms, consult a doctor immediately.
To determine the diagnosis of high leukocytes and determine the cause, the doctor will perform a physical examination and supporting examinations in the form of a complete blood test. After the cause of high leukocytes is known, the doctor will provide appropriate treatment to treat the cause.