Table of ContentsView AllTable of ContentsPrevalenceSymptomsDiagnosisTreatmentMonitoring
Table of ContentsView All
View All
Table of Contents
Prevalence
Symptoms
Diagnosis
Treatment
Monitoring
Eosinophilic asthma, also known as e-asthma, is one of the most common subtypes ofasthmadiagnosed in adulthood. Eosinophilic asthma occurs when a high number of eosinophils, a type of white blood cell, inflame the lungs. Why this occurs is unknown. Because lung samples can be difficult to obtain, elevated numbers of blood eosinophils are often used a surrogate for diagnosis in patients with difficult to control asthma.Allergic asthmais not the same as eosinophilic asthma. Eosinophilic asthma can occur in some atopic patients (meaning those patients that have a tendency toward allergies) but it can also occur without atopic predisposition.
Inflammation from eosinophilic asthma occurs as part of an allergic or immune system response, which releases a specific white blood cell calledeosinophils. When you have an increase in white blood cells, you will typically have an inflammatory response, which leads to thickening of your airways. The fluid andmucusthat results may lead to spasms in your airways (bronchioles) and cause your asthma symptoms.
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Asthma is an inflammatory disorder of the airways that can make it difficult to breathe. About one out of 13 people suffer from this chronic illness, and poor control of asthma can lead to risk for life-threatening asthma attacks.
Know that most of these exacerbations are preventable if the asthma is properly managed. While originally thought to be a single disorder, asthma actually has many subtypes that can alter how your asthma can best be controlled.
About 5% to 10% of people with asthma have severe asthma.While the prevalence of having eosinophilic asthma is relatively unknown, studies suggest that around 50% percent of cases of severe asthma are eosinophilic asthma.
If you are older than 35 when you are diagnosed with severe asthma you have a higher risk of being diagnosed with eosinophilic asthma. Your risk is the same regardless of your gender, and you have a lower risk of being diagnosed with eosinophilic asthma in your childhood and teenage years.
Many of the symptoms of eosinophilic asthma are the same as other forms of asthma, including:
Signs and Symptoms of Asthma
There are a few symptoms that may also be present that are not typically associated with asthma including:
While eosinophilic asthma is an immune response related to allergies, many people diagnosed with it do not suffer from allergies to mold, mildew, or other common allergens.
Eosinophilic asthma is under-diagnosed. It is not considered common even though the prevalence is thought to be higher than previously believed.
If eosinophilic asthma is the cause of your asthma and is not diagnosed, you may struggle to get your severe asthma under control.
Eosinophil Cell Count
Performing a cell count of eosinophils from an induced sputum sample is considered the gold standard measure of inflammatory cell counts, but it is difficult to obtain, time-consuming, and observer-dependent. It often requires the use of a specific lab staffed with experts.
When collecting the specimen, you want to ensure that you are not spitting saliva, but coughing up sputum from your airways. The coughed up specimen can then be analyzed in a lab to see if the sputum eosinophil count is equal to or great than 3%.
Airway Biopsy
Another way to determine whether you have e-asthma is with an airway biopsy, which is performed during a bronchoscopy. This procedure can be used to identify abnormal cells in the diagnosis of several different lung diseases.
However, this method is not recommended as the first step in identifying eosinophilic asthma unless a sufficient sputum sample can’t be obtained since it is an invasive procedure that requires some sedation and can have complications.
Other Methods
Other methods have been developed to help diagnose e-asthma. Your healthcare provider may check a complete blood count (CBC) to check for eosinophilia (increased eosinophil count).
Other diagnoses that may be considered if you have an elevated eosinophil count in your blood include parasitic infection, hypereosinophilic syndrome, autoimmune disorders, adrenal insufficiency, some cancers, and medication reactions.
What Your CBC Test Results Say About Your Health
Other tests may be used to help diagnose asthma. One of these is the fractional exhaled nitric oxide (FeNO) breathing test,which measures the amount of nitric oxide in your breath when you exhale. High levels are a possible indication of lung inflammation that may be a response to an allergen.
Many factors can affect the results of a FeNO test, including the use of steroids, age, sex, atopy (tendency to develop allergies), and smoking status.Although FeNO can play a useful role in determining if someone has asthma, it should not be relied on alone—either to diagnose the condition or to predict how it might progress, according to updated recommendations for asthma management issued in December 2020.
Sometimes a blood test is performed as part of an asthma workup to measure levels of periostin, a biomarker in the epithelial cells of the airways. Periostin levels tend to be elevated in response to asthma that activates certain immune cells (TH2).
However, while in some studies periostin testing has been shown to be an excellent substitute for testing sputum, in others results have been variable. Induced sputum and blood eosinophil counts are still preferable to FeNO and periostin according to most clinicians and guidelines.
Periostin is a biomarker in your airway epithelial cells. Periostin levels tend to be elevated in asthma that activates certain immune cells (TH2) and in some studies has been shown to be an excellent surrogate for testing sputum.
But results are variable in other studies and the test is not easily available. Induced sputum and blood eosinophil counts are still preferable to FeNO and periostin according to most clinicians and guidelines.
First-line treatment of eosinophilic asthma should include your standard asthma treatment regimen. Often you will experience good results from inhaled corticosteroids (ICS) that are used as part of the standard asthma treatment guidelines.
If your healthcare provider has diagnosed you with eosinophilic asthma, they may alter the standard approach used with inhaled corticosteroids. Corticosteroid medications include:
While inhaled corticosteroids often have beneficial effects, some people have steroid-refractory eosinophilic asthma, which simply means that your asthma does not have symptomatic or clinical benefit from taking inhaled corticosteroids.
If you have tried one or more inhaled corticosteroids without benefit, your physician will likely step up your asthma care to include additional treatment options like long-acting bronchodilators (included in combination inhalers like Advair HFA and Symbicort) and/or leukotriene modifiers like Singulair (montelukast). If standard step-up therapies are insufficient for controlling your asthma, you may discuss some of the more recently discovered medications used to target eosinophils in eosinophilic asthma specifically.
There are five targeted therapies that have received approval from the U.S. Food and Drug Administration (FDA) for the treatment of allergic asthma:
The five medications listed above have shown favorable results if you are still symptomatic despite good adherence to your prescribed corticosteroid regimen. Of these, omalizumab tends to be the least successful, as it affects allergies more specifically than mepolizumab and reslizumab.
These medications are also generally well tolerated with minimal side-effects with the likelihood that you will also be able to decrease your use of corticosteroids. Minimizing use of steroids also brings a reduction in side effects that can increase your quality of life.
A standard follow-up appointment is about two to six weeks after starting a new medication. If you have experienced positive results, you will continue on the medication prescribed and follow up in one to six months. Even if you are not on one of the newer asthma medications targeting eosinophils, most should see a physician approximately once every three months for evaluation and management of chronic persistent asthma.
A Word From Verywell
While eosinophilic asthma is often associated with severe asthma, treatment is possible if diagnosed properly. Untreated eosinophilic asthma will likely result in difficulty controlling asthma exacerbations—which not only worsens your quality of life but can be life-threatening. Working with your pulmonologist or allergist/immunologist with targeted therapies can help you get back the quality of life that you deserve and may reduce the frequency of your asthma exacerbations.
21 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Katz LE, Gleich GJ, Hartley BF, Yancey SW, Ortega HG.Blood eosinophil count is a useful biomarker to identify patients with severe eosinophilic asthma.Annals ATS. 2014;11(4):531-536. doi:10.1513/AnnalsATS.201310-354OCPoletti, V.Eosinophilic bronchiolitis: is it a new syndrome?Eur Respir J. 2013;41(5):1012-1013. doi:10.1183/09031936.00041813Asthma and Allergy Foundation of America.Asthma facts and figures.Hekking PW, Wener RR, Amelink M, Zwinderman AH, Bouvy ML, Bel EH.The prevalence of severe refractory asthma.Journal of Allergy and Clinical Immunology. 2015;135(4):896-902. doi:10.1016/j.jaci.2014.08.042Skolnik, N. and Carnahan, S.,Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion.2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966American Partnership for Eosinophilic Disorders.Eosinophilic asthma.de Groot JC, ten Brinke A, Bel EH.Management of the patient with eosinophilic asthma: a new era begins.ERJ Open Res. 2015;1(1):00024-2015-. doi:10.1183/23120541.00024-2015Doherty T, Walford H.Diagnosis and management of eosinophilic asthma: a US perspective.JAA. 2014;7:53–65. doi:10.2147/JAA.S39119Saha K, Saha D, Bandyopadhyay A, Roy P, Chakraborty S, Jash D.Usefulness of induced sputum eosinophil count to assess severity and treatment outcome in asthma patients.Lung India. 2013;30(2):117-. doi:10.4103/0970-2113.110419American Lung Association.Bronchoscopy.Mount Sinai.Eosinophil count - absolute.Scott M, Raza A, Karmaus W, et al.Influence of atopy and asthma on exhaled nitric oxide in an unselected birth cohort study.Thorax. 2010;65(3):258-262. doi:10.1136/thx.2009.125443Cloutier MM, Baptist AP, Blake KV, et al.2020 focused updates to the asthma management guidelines: A report from the national asthma education and prevention program coordinating committee expert panel working group.Journal of Allergy and Clinical Immunology. 2020;146(6):1217-1270. doi:10.1016/j.jaci.2020.10.003American Academy of Allergy, Asthma, & Immunology.Corticosteroids defined.Humbert M, Taillé C, Mala L, Le Gros V, Just J, Molimard M.Omalizumab effectiveness in patients with severe allergic asthma according to blood eosinophil count: the STELLAIR study.Eur Respir J. 2018;51(5):1702523-. doi:10.1183/13993003.02523-2017Choy MS, Dixit D, Bridgeman MB.Mepolizumab (Nucala) for severe eosinophilic asthma.P & T: A Peer-Reviewed Journal for Formulary Management. 2016;41(10):619-622.Hom S, Pisano M.Reslizumab (Cinqair): an interleukin-5 antagonist for severe asthma of the eosinophilic phenotype.P & T : a peer-reviewed journal for formulary management. 2017;42(9):564-568.Food And Drug Administration.Xolair label.Bleecker ER, Wechsler ME, FitzGerald JM, et al.Baseline patient factors impact on the clinical efficacy of benralizumab for severe asthma.Eur Respir J. 2018;52(4):1800936-. doi:10.1183/13993003.00936-2018FDA.Dupixent label.NIH National Heart, Lung, and Blood Institute.Asthma care quick reference.Additional ReadingAmerican College of Allergy, Asthma, & Immunology.Asthma facts.Skolnik NS, Carnahan SP.Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion. 2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966
21 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Katz LE, Gleich GJ, Hartley BF, Yancey SW, Ortega HG.Blood eosinophil count is a useful biomarker to identify patients with severe eosinophilic asthma.Annals ATS. 2014;11(4):531-536. doi:10.1513/AnnalsATS.201310-354OCPoletti, V.Eosinophilic bronchiolitis: is it a new syndrome?Eur Respir J. 2013;41(5):1012-1013. doi:10.1183/09031936.00041813Asthma and Allergy Foundation of America.Asthma facts and figures.Hekking PW, Wener RR, Amelink M, Zwinderman AH, Bouvy ML, Bel EH.The prevalence of severe refractory asthma.Journal of Allergy and Clinical Immunology. 2015;135(4):896-902. doi:10.1016/j.jaci.2014.08.042Skolnik, N. and Carnahan, S.,Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion.2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966American Partnership for Eosinophilic Disorders.Eosinophilic asthma.de Groot JC, ten Brinke A, Bel EH.Management of the patient with eosinophilic asthma: a new era begins.ERJ Open Res. 2015;1(1):00024-2015-. doi:10.1183/23120541.00024-2015Doherty T, Walford H.Diagnosis and management of eosinophilic asthma: a US perspective.JAA. 2014;7:53–65. doi:10.2147/JAA.S39119Saha K, Saha D, Bandyopadhyay A, Roy P, Chakraborty S, Jash D.Usefulness of induced sputum eosinophil count to assess severity and treatment outcome in asthma patients.Lung India. 2013;30(2):117-. doi:10.4103/0970-2113.110419American Lung Association.Bronchoscopy.Mount Sinai.Eosinophil count - absolute.Scott M, Raza A, Karmaus W, et al.Influence of atopy and asthma on exhaled nitric oxide in an unselected birth cohort study.Thorax. 2010;65(3):258-262. doi:10.1136/thx.2009.125443Cloutier MM, Baptist AP, Blake KV, et al.2020 focused updates to the asthma management guidelines: A report from the national asthma education and prevention program coordinating committee expert panel working group.Journal of Allergy and Clinical Immunology. 2020;146(6):1217-1270. doi:10.1016/j.jaci.2020.10.003American Academy of Allergy, Asthma, & Immunology.Corticosteroids defined.Humbert M, Taillé C, Mala L, Le Gros V, Just J, Molimard M.Omalizumab effectiveness in patients with severe allergic asthma according to blood eosinophil count: the STELLAIR study.Eur Respir J. 2018;51(5):1702523-. doi:10.1183/13993003.02523-2017Choy MS, Dixit D, Bridgeman MB.Mepolizumab (Nucala) for severe eosinophilic asthma.P & T: A Peer-Reviewed Journal for Formulary Management. 2016;41(10):619-622.Hom S, Pisano M.Reslizumab (Cinqair): an interleukin-5 antagonist for severe asthma of the eosinophilic phenotype.P & T : a peer-reviewed journal for formulary management. 2017;42(9):564-568.Food And Drug Administration.Xolair label.Bleecker ER, Wechsler ME, FitzGerald JM, et al.Baseline patient factors impact on the clinical efficacy of benralizumab for severe asthma.Eur Respir J. 2018;52(4):1800936-. doi:10.1183/13993003.00936-2018FDA.Dupixent label.NIH National Heart, Lung, and Blood Institute.Asthma care quick reference.Additional ReadingAmerican College of Allergy, Asthma, & Immunology.Asthma facts.Skolnik NS, Carnahan SP.Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion. 2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Katz LE, Gleich GJ, Hartley BF, Yancey SW, Ortega HG.Blood eosinophil count is a useful biomarker to identify patients with severe eosinophilic asthma.Annals ATS. 2014;11(4):531-536. doi:10.1513/AnnalsATS.201310-354OCPoletti, V.Eosinophilic bronchiolitis: is it a new syndrome?Eur Respir J. 2013;41(5):1012-1013. doi:10.1183/09031936.00041813Asthma and Allergy Foundation of America.Asthma facts and figures.Hekking PW, Wener RR, Amelink M, Zwinderman AH, Bouvy ML, Bel EH.The prevalence of severe refractory asthma.Journal of Allergy and Clinical Immunology. 2015;135(4):896-902. doi:10.1016/j.jaci.2014.08.042Skolnik, N. and Carnahan, S.,Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion.2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966American Partnership for Eosinophilic Disorders.Eosinophilic asthma.de Groot JC, ten Brinke A, Bel EH.Management of the patient with eosinophilic asthma: a new era begins.ERJ Open Res. 2015;1(1):00024-2015-. doi:10.1183/23120541.00024-2015Doherty T, Walford H.Diagnosis and management of eosinophilic asthma: a US perspective.JAA. 2014;7:53–65. doi:10.2147/JAA.S39119Saha K, Saha D, Bandyopadhyay A, Roy P, Chakraborty S, Jash D.Usefulness of induced sputum eosinophil count to assess severity and treatment outcome in asthma patients.Lung India. 2013;30(2):117-. doi:10.4103/0970-2113.110419American Lung Association.Bronchoscopy.Mount Sinai.Eosinophil count - absolute.Scott M, Raza A, Karmaus W, et al.Influence of atopy and asthma on exhaled nitric oxide in an unselected birth cohort study.Thorax. 2010;65(3):258-262. doi:10.1136/thx.2009.125443Cloutier MM, Baptist AP, Blake KV, et al.2020 focused updates to the asthma management guidelines: A report from the national asthma education and prevention program coordinating committee expert panel working group.Journal of Allergy and Clinical Immunology. 2020;146(6):1217-1270. doi:10.1016/j.jaci.2020.10.003American Academy of Allergy, Asthma, & Immunology.Corticosteroids defined.Humbert M, Taillé C, Mala L, Le Gros V, Just J, Molimard M.Omalizumab effectiveness in patients with severe allergic asthma according to blood eosinophil count: the STELLAIR study.Eur Respir J. 2018;51(5):1702523-. doi:10.1183/13993003.02523-2017Choy MS, Dixit D, Bridgeman MB.Mepolizumab (Nucala) for severe eosinophilic asthma.P & T: A Peer-Reviewed Journal for Formulary Management. 2016;41(10):619-622.Hom S, Pisano M.Reslizumab (Cinqair): an interleukin-5 antagonist for severe asthma of the eosinophilic phenotype.P & T : a peer-reviewed journal for formulary management. 2017;42(9):564-568.Food And Drug Administration.Xolair label.Bleecker ER, Wechsler ME, FitzGerald JM, et al.Baseline patient factors impact on the clinical efficacy of benralizumab for severe asthma.Eur Respir J. 2018;52(4):1800936-. doi:10.1183/13993003.00936-2018FDA.Dupixent label.NIH National Heart, Lung, and Blood Institute.Asthma care quick reference.
Katz LE, Gleich GJ, Hartley BF, Yancey SW, Ortega HG.Blood eosinophil count is a useful biomarker to identify patients with severe eosinophilic asthma.Annals ATS. 2014;11(4):531-536. doi:10.1513/AnnalsATS.201310-354OC
Poletti, V.Eosinophilic bronchiolitis: is it a new syndrome?Eur Respir J. 2013;41(5):1012-1013. doi:10.1183/09031936.00041813
Asthma and Allergy Foundation of America.Asthma facts and figures.
Hekking PW, Wener RR, Amelink M, Zwinderman AH, Bouvy ML, Bel EH.The prevalence of severe refractory asthma.Journal of Allergy and Clinical Immunology. 2015;135(4):896-902. doi:10.1016/j.jaci.2014.08.042
Skolnik, N. and Carnahan, S.,Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion.2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966
American Partnership for Eosinophilic Disorders.Eosinophilic asthma.
de Groot JC, ten Brinke A, Bel EH.Management of the patient with eosinophilic asthma: a new era begins.ERJ Open Res. 2015;1(1):00024-2015-. doi:10.1183/23120541.00024-2015
Doherty T, Walford H.Diagnosis and management of eosinophilic asthma: a US perspective.JAA. 2014;7:53–65. doi:10.2147/JAA.S39119
Saha K, Saha D, Bandyopadhyay A, Roy P, Chakraborty S, Jash D.Usefulness of induced sputum eosinophil count to assess severity and treatment outcome in asthma patients.Lung India. 2013;30(2):117-. doi:10.4103/0970-2113.110419
American Lung Association.Bronchoscopy.
Mount Sinai.Eosinophil count - absolute.
Scott M, Raza A, Karmaus W, et al.Influence of atopy and asthma on exhaled nitric oxide in an unselected birth cohort study.Thorax. 2010;65(3):258-262. doi:10.1136/thx.2009.125443
Cloutier MM, Baptist AP, Blake KV, et al.2020 focused updates to the asthma management guidelines: A report from the national asthma education and prevention program coordinating committee expert panel working group.Journal of Allergy and Clinical Immunology. 2020;146(6):1217-1270. doi:10.1016/j.jaci.2020.10.003
American Academy of Allergy, Asthma, & Immunology.Corticosteroids defined.
Humbert M, Taillé C, Mala L, Le Gros V, Just J, Molimard M.Omalizumab effectiveness in patients with severe allergic asthma according to blood eosinophil count: the STELLAIR study.Eur Respir J. 2018;51(5):1702523-. doi:10.1183/13993003.02523-2017
Choy MS, Dixit D, Bridgeman MB.Mepolizumab (Nucala) for severe eosinophilic asthma.P & T: A Peer-Reviewed Journal for Formulary Management. 2016;41(10):619-622.
Hom S, Pisano M.Reslizumab (Cinqair): an interleukin-5 antagonist for severe asthma of the eosinophilic phenotype.P & T : a peer-reviewed journal for formulary management. 2017;42(9):564-568.
Food And Drug Administration.Xolair label.
Bleecker ER, Wechsler ME, FitzGerald JM, et al.Baseline patient factors impact on the clinical efficacy of benralizumab for severe asthma.Eur Respir J. 2018;52(4):1800936-. doi:10.1183/13993003.00936-2018
FDA.Dupixent label.
NIH National Heart, Lung, and Blood Institute.Asthma care quick reference.
American College of Allergy, Asthma, & Immunology.Asthma facts.Skolnik NS, Carnahan SP.Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion. 2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966
American College of Allergy, Asthma, & Immunology.Asthma facts.
Skolnik NS, Carnahan SP.Primary care of asthma: new options for severe eosinophilic asthma.Current Medical Research and Opinion. 2019;35(7):1309-1318. doi:10.1080/03007995.2019.1595966
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