Leukocytosis: Overview, Causes, Symptoms, and Treatment
Leukocytosis means high white blood cell count, often due to infection, stress, or inflammation. Learn its causes, symptoms, diagnosis, and treatment options.
Written by Dr. Siri Nallapu
Reviewed by Dr. Rohinipriyanka Pondugula MBBS
Last updated on 21st Aug, 2025
If you’ve recently had a blood test and your doctor mentioned that you have leukocytosis, you might be wondering what it means and whether it’s something to worry about. Leukocytosis is a condition where your white blood cell (WBC) count is higher than normal. While it can sometimes indicate an underlying health issue, it’s not always a cause for alarm.
In this article, we’ll break down leukocytosis in simple terms—what it is, what causes it, common symptoms, and how it’s treated—so you can better understand your health and take the right steps if needed.
What Is Leukocytosis?
White blood cells (WBCs) are an essential part of your immune system. They help your body fight infections, diseases, and foreign invaders. A normal WBC count ranges between 4,000 and 11,000 cells per microliter of blood. When this count goes beyond 11,000, it’s called leukocytosis.
There are different types of white blood cells, and the kind that’s elevated can give clues about the underlying cause.
The major types include:
- Neutrophils (fight bacterial infections)
- Lymphocytes (fight viral infections and help with immunity)
- Monocytes (clean up dead cells and fight chronic infections)
- Eosinophils (respond to allergies and parasites)
- Basophils (involved in inflammatory responses)
Depending on which type is high, your doctor can determine what might be causing the increase.
Common Causes of Leukocytosis
Leukocytosis isn’t a disease itself but rather a sign that your body is responding to something. Some common causes include:
1. Infections
- Bacterial infections (like pneumonia or urinary tract infections) often raise neutrophil counts.
- Viral infections (such as flu or COVID-19) may increase lymphocytes.
- Parasitic or allergic reactions can elevate eosinophils.
2. Inflammation or Injury
- Conditions like arthritis, inflammatory bowel disease (IBD), or tissue damage (after surgery or burns) can trigger a high WBC count.
3. Stress or Physical Strain
- Emotional stress, intense exercise, or even pregnancy can temporarily increase WBCs.
4. Medications
- Certain drugs, like steroids (prednisone) or epinephrine, can lead to leukocytosis.
5. Bone Marrow Disorders
- In rare cases, conditions like leukemia, myelofibrosis, or polycythemia vera cause abnormal white blood cell production.
If your WBC count is high, your doctor may order further tests to pinpoint the exact cause.
Consult Top General Practitioner
Symptoms of Leukocytosis
Leukocytosis itself doesn’t always cause symptoms—it’s usually the underlying condition that leads to noticeable signs. However, some possible symptoms include:
- Fever or chills (if due to infection)
- Fatigue or weakness
- Frequent infections
- Unexplained weight loss
- Easy bruising or bleeding (if related to blood disorders)
- Swollen lymph nodes
If you experience any of these along with a high WBC count, consult your doctor for further evaluation.
How Is Leukocytosis Diagnosed?
A simple complete blood count (CBC) test can detect leukocytosis. If your WBC count is high, your doctor may recommend:
- Peripheral blood smear (to examine blood cells under a microscope)
- Bone marrow biopsy (if a blood disorder is suspected)
- Infection tests (like cultures or viral panels)
- Imaging tests (X-rays, CT scans) if inflammation or tumors are possible
These tests help determine the exact reason behind the elevated WBCs.
Treatment and Management
Since leukocytosis is a symptom rather than a disease, treatment focuses on addressing the underlying cause:
1. Treating Infections
- Antibiotics for bacterial infections
- Antivirals or supportive care for viral infections
2. Managing Inflammation
- Anti-inflammatory medications for conditions like arthritis
3. Adjusting Medications
- If a drug is causing high WBCs, your doctor may change your prescription.
4. Addressing Blood Disorders
- Chemotherapy, radiation, or targeted therapy may be needed for leukemia or other bone marrow conditions.
Lifestyle Tips to Support Immune Health
- Eat a balanced diet (rich in fruits, vegetables, and lean proteins)
- Stay hydrated to help flush out toxins
- Exercise moderately (avoid extreme physical stress)
- Get enough sleep (7-9 hours per night)
- Manage stress (through yoga, meditation, or deep breathing.
When to See a Doctor
Most cases of leukocytosis are temporary and resolve once the underlying issue (like an infection) is treated. However, consult your doctor if you notice:
- Persistent high WBC counts without an obvious cause
- Unexplained fatigue, weight loss, or night sweats
- Frequent infections or unusual bruising
If needed, you can book a consultation or schedule a CBC test through Apollo 24|7 for a quick and convenient check-up.
Final Thoughts
Leukocytosis is usually a sign that your body is fighting something—whether it’s an infection, inflammation, or stress. While it can sometimes indicate a more serious condition, most cases are harmless and manageable.
If you’ve been diagnosed with a high WBC count, don’t panic. Work with your doctor to find the cause and follow their recommended treatment plan.
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Consult Top General Practitioner
Dr Syed Mateen Pasha
General Physician
2 Years • MBBS
Bengaluru
PRESTIGE SHANTHINIKETAN - SOCIETY CLINIC, Bengaluru
Dr. Gaddam Manoj
General Practitioner
1 Years • MBBS
Hyderabad
Aaradhya clinic, Hyderabad
Dr. Anand Ravi
General Physician
2 Years • MBBS
Bengaluru
PRESTIGE SHANTHINIKETAN - SOCIETY CLINIC, Bengaluru
Dr. Ikram
General Practitioner
1 Years • MBBS
Hyderabad
Badar clinic, Hyderabad
Dr. Karanam Kondalamma
General Practitioner
4 Years • MBBS
Hyderabad
KK Clinic, Hyderabad