What is the WBC in the blood test, the norm by age (table), causes of increase and decrease

White blood cells (WBC), also known as leukocytes, are an essential part of our immune system. They play a crucial role in protecting our body from infections and diseases. A WBC count is a standard test included in a complete blood count (CBC) that measures the number of WBCs present in our blood.

Normal WBC Count by Age:

Age Range	Normal WBC Count (per microliter of blood)
Newborns	9,000 - 30,000
0 - 2 years	6,200 - 17,000
2 - 6 years	6,000 - 17,500
6 - 12 years	4,500 - 13,500
12 - 18 years	4,500 - 11,000
Adults	4,500 - 11,000

Causes of High WBC Count:

A high WBC count, also known as leukocytosis, can be caused due to various reasons, including:

• Infections: bacterial, viral, fungal, or parasitic infections can cause an increase in WBC count.
• Inflammatory conditions: autoimmune diseases, such as rheumatoid arthritis or inflammatory bowel disease, can cause high WBC counts.
• Medications: certain medications, such as corticosteroids, can cause an increase in WBC count.
• Leukemia: a type of blood cancer can also cause high WBC count.

Causes of Low WBC Count:

A low WBC count, also known as leukopenia, can be caused due to various reasons, including:

• Bone marrow disorders: bone marrow disorders, such as aplastic anemia or myelodysplastic syndrome, can cause low WBC counts.
• Infections: viral infections, such as HIV or hepatitis, can cause a decrease in WBC count.
• Medications: certain medications, such as chemotherapy or antibiotics, can cause a decrease in WBC count.
• Autoimmune diseases: autoimmune diseases, such as lupus, can cause low WBC counts.

It's important to note that a WBC count is just one component of a complete blood count (CBC) and should be interpreted in conjunction with other components of the CBC and the patient's overall health status. If you have concerns about your WBC count or other components of your blood test, consult your healthcare provider.

In conclusion, understanding your WBC count is essential in maintaining your overall health. A regular blood test can help you keep track of your WBC count and detect any abnormalities early on.