Monitoring and Steroid-Sparing Agents for EGPA Patients on Prednisolone 10mg Daily
For a patient with Eosinophilic Granulomatosis with Polyangiitis (EGPA) who is stable on prednisolone 10mg daily, mepolizumab should be offered as the first-line steroid-sparing agent, with a recommended dose of 300mg subcutaneously every 4 weeks. 1, 2
Monitoring Instructions for GP
Regular Clinical Assessment
- Monitor disease activity using Birmingham Vasculitis Activity Score (BVAS) at each visit
- Assess for signs of relapse: new or worsening respiratory symptoms, neurological symptoms, skin manifestations, or other organ involvement 1
- Define remission as BVAS of zero with prednisolone dose ≤7.5mg daily 1
Laboratory Monitoring
- Complete blood count with differential (focus on eosinophil count) every 3 months
- Renal function tests and urinalysis every 3-6 months
- Inflammatory markers (ESR, CRP) every 3 months
- ANCA testing in patients who were initially MPO-ANCA positive 1
Organ-Specific Monitoring
- Pulmonary function tests every 6-12 months (more frequently with respiratory symptoms)
- Echocardiography annually (more frequently with cardiac symptoms)
- Electrocardiography annually
- Neurological assessment if symptoms of neuropathy develop or worsen 1
Comorbidity Monitoring
- Bone density assessment annually for patients on long-term steroids
- Blood pressure and blood glucose monitoring
- Screen for infections, particularly if on immunosuppressive therapy
- Consider Pneumocystis jirovecii prophylaxis if additional immunosuppressants are used 1
Steroid-Sparing Agents
First-Line Option: Mepolizumab
- FDA-approved for EGPA at 300mg subcutaneously every 4 weeks 2
- Demonstrated efficacy in:
- Particularly effective for respiratory manifestations and peripheral neuropathy 3
- Administration: Three separate 100mg injections at least 5cm apart 2
Alternative Options Based on Disease Severity and ANCA Status
For Severe EGPA (with organ-threatening manifestations):
- Rituximab - particularly effective in ANCA-positive patients 1
- Cyclophosphamide - for induction in severe disease 1
- Traditional DMARDs (in combination with glucocorticoids):
For Non-Severe EGPA:
- Mepolizumab (preferred) 1, 5
- Lower dose mepolizumab (100mg every 4 weeks) may be sufficient in some patients, particularly those with predominantly respiratory manifestations 6
Practical Considerations
Steroid Tapering
- Once steroid-sparing agent is initiated, aim to gradually reduce prednisolone to ≤4mg daily
- Typical tapering schedule: reduce by 1-2.5mg every 2-4 weeks as tolerated
- Monitor closely for disease flares during tapering 1
Monitoring Treatment Response
- Assess clinical response within 3-6 months of initiating steroid-sparing therapy
- Evaluate steroid-sparing effect (ability to reduce prednisolone dose)
- Monitor eosinophil counts, though they don't always correlate with disease activity 1
Special Considerations
- ANCA-positive patients (30-40% of EGPA cases) may respond differently to therapy than ANCA-negative patients
- ANCA-positive patients more frequently have glomerulonephritis, neuropathy, and purpura
- ANCA-negative patients more frequently have cardiac and lung involvement 1
Pitfalls and Caveats
- Eosinophil count alone is not a reliable marker of disease activity; relapses can occur without increased eosinophils 1
- Distinguish between systemic vasculitis relapse and isolated respiratory symptom exacerbation 1
- Cardiac involvement may be subclinical but carries poor prognosis; consider cardiac MRI in patients with suspected cardiac involvement 1, 7
- Standard cardiac tests may miss early cardiac involvement; cardiac ECT has higher sensitivity 7
By implementing these monitoring protocols and considering mepolizumab as the primary steroid-sparing agent, you can help maintain disease remission while minimizing the long-term complications of corticosteroid therapy in your patient with EGPA.