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What is Leukocytosis?
Leukocytosis is a medical condition characterized by an elevated number of white blood cells (leukocytes) in the blood, often abbreviated as WBC in blood tests. Medically, leukocytosis is defined as a WBC value above 11×109/L. White blood cells are an important part of the body's immune system and help fight infections and other diseases.
The increase can be divided by degree:
- Mild leukocytosis: 11 to 15×109/L
- Moderate leukocytosis: 15 to 30×109/L
- Severe leukocytosis: Over 30×109/L
Diagnosis of Leukocytosis
The diagnosis of leukocytosis is made through a blood test that measures the amount of white blood cells in the blood. If the values are above the reference range, further investigation is often done with a differential white blood cell count. It provides a detailed picture of which specific cell types are elevated, which helps identify the underlying cause, such as infection, inflammation, or other medical conditions.
Causes of Leukocytosis
There are several different reasons why a person may develop leukocytosis. Here are some of the most common:
- Infections: The most common cause. When the body fights an infection (caused by bacteria or viruses, for example), the bone marrow produces more white blood cells.
- Inflammation: Chronic or acute inflammatory diseases, such as rheumatoid arthritis or inflammatory bowel disease, can lead to an increase in white blood cells.
- Stress: Physical or severe emotional stress (such as major surgery, trauma, or acute illness) can trigger a temporary increase in white blood cells.
- Medications: Certain medications, especially corticosteroids (cortisone) and NSAIDs, can cause an increase in white blood cells.
- Bone marrow diseases: Diseases that affect the bone marrow where blood cells are formed can lead to leukocytosis. This includes various types of leukemia and other myeloproliferative conditions.
Symptoms of Leukocytosis
Leukocytosis itself usually does not cause any specific symptoms, but is often discovered as an incidental finding during testing. However, the underlying cause can cause symptoms.
There are certain alarm symptoms associated with elevated white blood cells that should always prompt further medical assessment:
- Unexplained fever
- Extreme fatigue or malaise
- Involuntary weight loss
- Heavy night sweats
- Easy bruising or bleeding
Treatment of Leukocytosis
The treatment of leukocytosis is completely tailored to the underlying cause. If an infection is behind the condition, antibiotics or antiviral drugs can be used. In inflammatory diseases, anti-inflammatory or immunomodulatory drugs may be used to reduce inflammation. If the leukocytosis is caused by medication, the doctor may need to adjust the dosage or evaluate alternative treatment options.
