What is the treatment for acute eosinophilic asthma?

Treatment for Acute Eosinophilic Asthma

For acute eosinophilic asthma, initiate high-dose inhaled corticosteroids (budesonide or fluticasone) immediately, and add systemic corticosteroids (prednisone 1-2 mg/kg/day, maximum 60 mg) for severe presentations requiring urgent symptom relief, dehydration, significant weight loss, or respiratory compromise. 1, 2

Initial Assessment and Immediate Management

Severity Stratification

• Severe presentations requiring immediate systemic corticosteroids include: patients with severe dysphagia, dehydration, significant weight loss, respiratory distress, or those at risk for respiratory failure 2
• Moderate presentations can be managed with high-dose inhaled corticosteroids alone 1

First-Line Therapy: Inhaled Corticosteroids

Inhaled corticosteroids are the cornerstone of treatment for eosinophilic asthma, significantly reducing sputum eosinophil counts and improving symptoms within 4 weeks. 1

• Budesonide has demonstrated normalization of cough sensitivity after 4 weeks of treatment 1
• These agents are considered very safe for use in both children and adults with asthma and are routinely used as primary management 2
• The same inhaled steroid formulations used for asthma treatment are effective for eosinophilic inflammation 2

Systemic Corticosteroids for Acute/Severe Cases

When urgent symptom relief is required, systemic corticosteroids provide rapid clinical improvement within 7 days and histologic improvement within 4 weeks. 2

• Dosing: Prednisone 1-2 mg/kg/day (maximum 60 mg daily), similar to inflammatory bowel disease protocols 2
• Systemic corticosteroids effectively target multiple elements of the type 2/eosinophilic inflammatory pathway, leading to rapid reduction in eosinophilic inflammation 3
• Clinical improvement typically occurs within 7 days, with histologic improvement by 4 weeks 2
• Blood eosinophil counts decrease by approximately 30-36% within one month of initiation 4

Important caveat: Systemic corticosteroids carry significant side effects including weight gain, cushingoid appearance (40% incidence), growth abnormalities, bone abnormalities, mood disturbances, and adrenal axis suppression 2

Transitioning and Maintenance Strategy

Corticosteroid Tapering

• Never discontinue systemic or inhaled corticosteroids abruptly upon improvement 5, 6
• Taper systemic corticosteroids gradually over 8 weeks once clinical improvement is achieved 2
• Transition to high-dose inhaled corticosteroids for maintenance 1

For Persistent or Refractory Disease

If symptoms persist despite high-dose inhaled corticosteroids, continue oral corticosteroids and consider adding biologics. 1

Biologic Therapy Options (for steroid-refractory cases):

Mepolizumab (anti-IL-5):

• Dosing for severe asthma: 100 mg subcutaneously every 4 weeks for patients ≥12 years; 40 mg every 4 weeks for ages 6-11 years 5
• Reduces exacerbations and allows steroid sparing in severe eosinophilic asthma 7, 8
• Has been successfully used in ICU settings for steroid-refractory acute severe eosinophilic asthma requiring mechanical ventilation 9
• After 12 months, 23% of patients can be weaned off corticosteroids entirely 8

Benralizumab (anti-IL-5 receptor):

• Dosing: 30 mg subcutaneously every 4 weeks for first 3 doses, then every 8 weeks for patients ≥12 years; 10 mg for patients 6-11 years weighing <35 kg 6
• Provides similar steroid-sparing effects and reduces asthma exacerbations 8
• Median eosinophil count reduced from 365 cells/mm³ to 70 cells/mm³ at 12 months 8

Monitoring Response

• Clinical symptoms: Should improve within 7 days with systemic corticosteroids 2
• Blood eosinophil counts: Monitor regularly; expect 30-36% reduction within one month of corticosteroid initiation 4
• Sputum eosinophils: Should decrease significantly with inhaled corticosteroid therapy 1
• Pulmonary function: Assess FEV1 at follow-up visits 8

Critical Pitfalls to Avoid

• Do not use these therapies for acute bronchospasm or status asthmaticus—they are not rescue medications 5, 6
• Blood eosinophil counts remain suppressed for several weeks after corticosteroid discontinuation; timing of discontinuation affects accurate assessment of eosinophilic phenotype 4
• Approximately one-third of patients fail to achieve histologic remission with topical corticosteroids alone 2
• Resistance or insensitivity to corticosteroids is a feature of severe asthma, with persistent type 2 inflammation often occurring despite regular OCS use 3

Special Considerations

• Helminth infections: Treat pre-existing parasitic infections before initiating biologic therapy; discontinue biologics if patients become infected and don't respond to anti-helminth treatment 5, 6
• Herpes zoster: Consider vaccination before initiating mepolizumab if medically appropriate 5
• Hypersensitivity: Discontinue therapy immediately if anaphylaxis, angioedema, bronchospasm, or other hypersensitivity reactions occur 5, 6