Receiving abnormal blood test results can be stressful. But if you have hidradenitis suppurativa (HS) — a chronic inflammatory skin disease that causes painful skin lesions — having a high white blood cell (WBC) count, or leukocytosis, may not be surprising.

In this article, we’ll explain what WBCs do, how they’re connected to HS, and what having leukocytosis might mean for you.

What Are White Blood Cells?

WBCs (also called leukocytes) are part of your immune system. WBCs help your body fight infections and certain diseases.

WBCs can be found in your bloodstream and other tissues. There are different types of white blood cells, including granulocytes, monocytes, and lymphocytes (T and B cells).

What’s a Normal White Blood Cell Count?

Your doctor can check your WBC count with a blood test. The normal range for WBCs can be different depending on the lab that tests the blood sample. Most often, the following ranges are considered normal:

• Children — 5,000 to 10,000 WBCs per microliter of blood
• Women — 4,500 to 11,000 WBCs per microliter of blood
• Men — 5,000 to 10,000 WBCs per microliter of blood

What Does a High White Blood Cell Count Mean?

A high WBC count, or leukocytosis, usually means your immune system is fighting an infection or inflammation. This is a normal response.

An elevated WBC count can also be found in healthy pregnant people, people who smoke, those taking certain medications, or even those under a lot of stress —whether physical or emotional. Having a higher body weight can also be linked to a WBC count that’s higher than normal.

Does HS Cause a High White Blood Cell Count?

HS is a chronic inflammatory skin condition that causes painful, recurrent lesions and abscesses in areas where skin rubs together, like the armpits, groin, buttocks, and under the breasts. Over time, tunnels that connect multiple lumps (also called sinus tracts) and scarring may form.

Because HS is an inflammatory condition, it can affect your WBC count. However, HS is not an infection and isn’t caused by one.

A 2016 study found that people with HS often have a higher-than-normal WBC count and elevated levels of C-reactive protein (CRP), a marker of inflammation in the body.

Does Everyone With HS Have a High WBC Count?

It’s unclear how many people with HS have a high WBC count. One study found that people with HS found that half of the people treated at an HS outpatient center had leukocytosis (high WBC count).

However, more research with larger groups is needed to fully understand the connection between HS and high WBC counts.

How Does HS Cause High WBC Counts?

High levels of white blood cells and elevated levels of CRP in people with HS point to systemic inflammation.

Studies suggest that high WBC counts in HS may be linked to immune system activity and possibly infections.

One possible cause of HS could be an abnormal immune response, which could affect the amount of white blood cells found.

Interestingly, some treatments used for HS can also raise WBC counts. Some examples are corticosteroids such as prednisone or prednisolone, which may be used to manage HS flare-ups in the short term, and certain antibiotics prescribed to treat infected lesions.

Should You Worry About a High WBC Count?

A high WBC count is often expected in HS due to the inflammatory nature of the disease, especially during flare-ups or in severe cases.

However, having a high WBC count for a long time without an infection may be linked to other health issues, like high blood pressure or problems with glucose (sugar) tolerance.

HS lesions can sometimes get infected by bacteria from the skin. This is called a secondary infection and can raise your WBC count. If this happens, you may need additional treatment.

Leukocytosis can also be a sign of other health conditions unrelated to HS, which may be both short term (acute) or long term (chronic). These include:

• Bacterial or viral infections
• Allergies
• Blood cancers
• Heart attack (myocardial infarction)
• Certain autoimmune disorders

Your healthcare provider can check for non-HS-related causes of high WBC count. If you have any symptoms of other conditions, they may run additional tests to diagnose or rule out other causes of high WBC count.

How Is a High White Blood Cell Count Treated?

A high WBC count isn’t a medical condition itself, and doesn’t cause any symptoms. Instead, you may experience symptoms of the condition that causes a high WBC count, such as HS.

For people with HS, medications that affect the immune system, like biologics, may help lower WBC counts over time.

If HS sores become infected, treatment includes oral antibiotics (taken by mouth) or topical antibiotics (applied on the skin). After treatment, white blood cell levels usually return to their previous levels.

Treating High WBC Count Due to Other Causes

If something other than HS is causing a high WBC count, treating that condition will help lower the WBC count. Treatment for a high WBC count depends on the cause:

• Bacterial infections (such as pneumonia or urinary tract infections) are treated with antibiotics.
• Viral infections (such as flu or herpes) may need antiviral medications.
• Allergic reactions are managed with antihistamines.
• Autoimmune diseases may be managed with corticosteroids or immunosuppressants.
• Cancer may require chemotherapy, radiotherapy, or other therapies.

If medications you’re taking are causing a high WBC count, your doctor may suggest switching to a different drug. Similarly, if you smoke or have a higher body weight, addressing these factors may help lower your WBC levels.

If stress is causing your leukocytosis, your primary care provider may refer you to a mental health professional.

Mindfulness practices like breathing exercises, yoga, and meditation can also help you manage stress better.

Talk With Others Who Understand

On myHSteam, the social network for people living with hidradenitis suppurativa and their loved ones, more than 46,000 members come together to ask questions, give advice, and share their stories with others who understand life with hidradenitis suppurativa.

Have you had a high white blood cell count? Were you advised to get additional treatment? Share your experience in the comments below or start a conversation by posting on your Activities page.