Basophilia, or basophilic disorder, is when your body produces too many basophils. Basophils are a white blood cell type that protects your body from infections. Basophilia may be a sign you have an infection, or it may be a sign of serious medical conditions like leukemia or autoimmune disease.


What is basophilia?

Basophilia, or basophilic disorder, is a sign your body is producing too many basophils. Basophils are one of the five white blood cell types that protect your body from infections or respond to intruders like parasites, fungi and cancer cells. Basophils drive your body’s reaction to allergens. They’re why you sneeze, cough or have a runny nose during allergy season or anytime you encounter an allergen. If your basophil count is unusually high, it is called basophilia. Basophilia may be a sign you have an infection, or it may be a sign of serious medical conditions like leukemia or autoimmune disease.


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Symptoms and Causes

What causes basophilia?

Basophilia happens when you have too many basophils. Several things can cause your basophil count to increase. Sometimes, basophilia symptoms are a sign your body is fighting a serious medical condition like hyperthyroidism or cancer. Other times, these symptoms indicate your body is battling a persistent infection or fending off an allergen.

What are the symptoms of basophilia?

Basophilia symptoms are similar to many medical conditions. Generally speaking, symptoms may include:

  • A temperature of 100.4 degrees Fahrenheit (33 ֯Celsius).
  • Feeling weak or tired.
  • Recurring or frequent infections.
  • Severe itching.
  • Skin rashes.
  • Swollen or painful joints.

What medical conditions are linked to basophilia?

Basophilia is linked to the following conditions, some more serious than others:

  • Acute myeloid leukemia (AML). This blood cancer typically affects adults. Chemotherapy is the top treatment for AML.
  • Chronic myelogenous leukemia. (CML). This blood cancer starts in the blood-forming cells in your bone marrow. Healthcare providers treat CML with targeted therapy or a bone marrow transplant.
  • Autoimmune diseases. Autoimmune diseases such as rheumatoid arthritis or multiple sclerosis happen when your immune system malfunctions and attacks your body instead of its intended targets. Healthcare providers manage autoimmune disease symptoms using a wide variety of treatments.
  • Polycythemia vera (PV). This is a blood disorder that happens when your body makes too many red blood cells. Healthcare providers treat PV with phlebotomy to remove iron from your blood or medication to thin your blood.
  • Myelofibrosis. This is a rare blood cancer that’s a form of chronic leukemia. It’s treated with targeted therapy and treatments for anemia.
  • Hypothyroidism. This condition happens when your thyroid gland doesn’t release enough of the thyroid hormone. Healthcare providers use hormone therapy to treat hypothyroidism.
  • Inflammatory bowel disease (IBD). People with IBD have chronic intestinal inflammation.
  • Crohn’s disease is an IBD. Providers treat IBDs with medications and surgery.


Diagnosis and Tests

How do healthcare providers diagnose basophilia?

Healthcare providers typically diagnose basophilia by taking samples of your blood so they can perform a test called a complete blood count (CBC). This test shows the number and condition of your white blood cells, your red blood cells and your platelets.

Since basophils are a type of white blood cell, your provider may opt for CBC with differential. This test details how many basophils and other white blood cells you have.

What does basophilia mean in a blood test?

Basophilia is more of a sign that something else is going on than it is a diagnosis. If your tests show a high basophil count, your provider might perform a physical examination and additional tests to find out what’s causing basophilia.

What is a normal basophil count?

A normal basophil count is .5% to 1% of your white blood cell count. This equals about zero to 300 basophils per microliter of blood in healthy adults. Basophil counts that fall outside this range may be a sign you have basophilia. Providers use your basophil count, along with other information such as your medical history and your symptoms, to treat the underlying condition causing your basophilia.


Management and Treatment

How do healthcare providers treat basophilia?

Basophilia can be a sign your body is reacting to allergens or overcoming an infection. It also can indicate more serious medical conditions. Regardless, healthcare providers treat basophilia by treating the underlying medical condition.


How can I prevent basophilia?

Basophilia is typically linked to an underlying medical condition that’s causing your basophil count to be too high. Since you may not be able to prevent the underlying condition, you likely can’t prevent basophilia.

Outlook / Prognosis

What can I expect if I have basophilia?

Basophilia is a symptom of underlying medical conditions that cause your basophil count to be too high or too low. Your healthcare provider will perform tests to learn more about your individual situation so they can treat any underlying medical condition.

Living With

How do I take care of myself?

Basophilia is a sign of underlying problems. Once you know what’s causing your basophilia, you can take steps to manage the underlying condition.

When should I see my healthcare provider?

You should contact your healthcare provider any time your basophilia symptoms or other conditions’ symptoms worsen or you develop new symptoms.

What questions should I ask my healthcare provider?

Basophilia happens when your body produces too many basophils, the white blood cell type that manages your body’s reactions to allergens. But an abnormal basophil count, or basophilia, may be a sign of more serious medical conditions like leukemia or autoimmune disease. You may want to ask your healthcare provider about basophilia. Here are some questions to consider:

  • What is basophilia?
  • How do you know I have basophilia?
  • How do you test for basophilia?
  • What do basophils mean in a blood count?
  • What is my basophil count and what is the range for a normal basophil count?
  • Does a high basophil count mean I have a serious illness?
  • Will I need more tests to find out why my basophil count is too high?

Additional Common Questions

What are the other white blood cell types?

White blood cells are a part of your immune system. There are five total white blood cell types. Each type is responsible for protecting your body from various intruders. In addition to basophils, white blood cells include:

  • Neutrophils. They target fungi, bacteria and foreign objects. If you have too many neutrophils, you have neutrophilia. If you don’t have enough neutrophils, you have neutropenia.
  • Eosinophils. They help basophils respond to allergens. Eosinophils also identify and destroy parasites and cancer cells. If you have too many eosinophils, you have eosinophila.
  • Lymphocytes. These cells protect against viral infections and produce proteins to help you fight infections.
  • Monocytes. These cells defend against infection by cleaning up damaged cells.

A note from Cleveland Clinic

Basophils — a type of white blood cell — are a part of the chain reaction to allergens that causes allergy symptoms like sneezing and coughing. Basophilia or basophilic disorder is a sign your body is producing too many basophils. A basophil count that’s too high may be a sign you have an infection or a more serious medical condition like leukemia or autoimmune disease. Basophilia symptoms include recurring or frequent infections, feeling feverish, weak and tired, or you have skin rashes, severe itching or swollen joints that don’t get better over time. If you have these symptoms and they don’t go away, contact your healthcare provider. They may recommend tests to check your basophil count so they can diagnose and treat any underlying medical conditions.

Medically Reviewed

Last reviewed on 11/17/2021.

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