What is the treatment approach for Systemic Lupus Erythematosus (SLE) with Interstitial Lung Disease (ILD)?

Treatment Approach for SLE with Interstitial Lung Disease (ILD)

For SLE-associated ILD, mycophenolate mofetil is the preferred first-line treatment, with short-term glucocorticoids as adjunctive therapy for initial management. 1, 2

First-Line Treatment Algorithm

1. Initial Assessment and Therapy:

   • Mycophenolate mofetil: 1000-1500 mg twice daily as the cornerstone therapy 1, 2
   • Short-term glucocorticoids:
     • Oral prednisone 0.5-1 mg/kg/day (maximum 60 mg/day) with taper to ≤10 mg/day over 3 months 1, 2
     • IV pulse methylprednisolone for severe or acute onset ILD 1

2. Alternative First-Line Options (if contraindications to mycophenolate exist):

   • Rituximab 1, 3
   • Azathioprine 1
   • Cyclophosphamide (for severe disease) 1

3. Medications to Avoid as First-Line Therapy:

   • Leflunomide 1
   • Methotrexate 1
   • TNF inhibitors 1
   • Abatacept 1
   • Pirfenidone 1

Management of Progressive Disease

If disease progression occurs despite first-line therapy (defined as >5% decline in FVC over 12 months or meeting INBUILD criteria), consider:

1. Recommended Options for Progressive SLE-ILD 1:

   • Mycophenolate (if not already used)
   • Rituximab
   • Cyclophosphamide
   • Nintedanib

2. Avoid Long-Term Glucocorticoids for progressive disease 1

Management of Rapidly Progressive ILD in SLE

For rapidly progressive ILD (RP-ILD), which represents a medical emergency:

1. First-Line Treatment 1:

   • Pulse IV methylprednisolone
   • Combination therapy with multiple agents:
     • Rituximab
     • Cyclophosphamide
     • IVIG
     • Mycophenolate

2. Early Referral for lung transplantation evaluation 1

Monitoring and Follow-up

• Pulmonary function tests (PFTs) every 3-6 months 2
• High-resolution CT (HRCT) at baseline and as clinically indicated 2
• Monitor for 5% decline in FVC, which is associated with approximately 2-fold increase in mortality 2

Important Considerations and Pitfalls

• Hydroxychloroquine: Should be continued for management of underlying SLE 4, 5
• Comorbidities: Address GERD and pulmonary hypertension, which may exacerbate ILD 2
• Pitfalls to Avoid:
  • Delaying treatment escalation can lead to irreversible fibrosis 2
  • Using monotherapy for rapidly progressive disease 2
  • Inadequate monitoring of pulmonary function 2

Special Considerations for SLE-ILD

• SLE-associated ILD tends to be milder with more favorable prognosis compared to other connective tissue disease-associated ILDs 6, 7
• SLE-ILD is more common in patients with CTD overlap syndromes 6
• B-cell targeted therapies like rituximab may be particularly effective when SLE and ILD coexist 3, 5

The treatment approach for SLE-ILD requires close collaboration between rheumatologists and pulmonologists to optimize outcomes and minimize complications from both the disease and its treatments.