What is the management approach for mucous membrane pemphigoid?

Management Approach for Mucous Membrane Pemphigoid

Treatment of mucous membrane pemphigoid (MMP) requires aggressive immunosuppressive therapy to prevent scarring and organ dysfunction, with therapy selection based on disease severity and affected sites.

Disease Overview

Mucous membrane pemphigoid (MMP) is a chronic autoimmune subepithelial blistering disease characterized by:

• Erosions and scarring of mucous membranes
• Potential involvement of oral cavity, eyes, pharynx, larynx, esophagus, and genital mucosa
• High morbidity due to scarring that can lead to blindness, esophageal/laryngeal stenosis, and strictures 1

Diagnosis

Diagnosis requires:

• Clinical presentation of blisters/erosions on mucous membranes
• Histopathology showing subepithelial blisters with inflammatory infiltrate
• Direct immunofluorescence (DIF) from perilesional tissue showing linear IgG and/or C3 deposits along basement membrane zone
• Indirect immunofluorescence (IIF) on salt-split skin showing autoantibodies binding to epidermal side 2

Treatment Algorithm Based on Disease Severity

1. Mild Disease (Oral Mucosa Only, Limited Lesions)

• First-line: Topical high-potency corticosteroids
  • Clobetasol propionate 0.05% in bioadhesive gel 2-3 times daily 3
  • Combine with chlorhexidine mouthwashes and antifungal prophylaxis (miconazole gel) 3, 4
• Alternative: Dapsone ≤1.0 mg/kg/day (check G6PD before starting) 1

2. Moderate Disease (Extensive Oral Lesions or Multiple Mucosal Sites Without Ocular Involvement)

• First-line: Systemic corticosteroids + adjuvant therapy
  • Prednisone 0.5-0.75 mg/kg/day (not exceeding 52.5 mg daily for 70kg patient) 5
  • Add adjuvant therapy early to allow steroid tapering:
    • Doxycycline 100 mg/day + nicotinamide 500 mg/day 1
    • Azathioprine 1-2.5 mg/kg/day (check TPMT levels before starting) 1, 5
    • Mycophenolate mofetil (starting at 500 mg/day, increasing as needed) 2

3. Severe Disease (Ocular, Laryngeal, Esophageal Involvement or Rapidly Progressive Disease)

• First-line: Aggressive immunosuppression
  • Prednisone 1 mg/kg/day + cyclophosphamide 2
  • OR Rituximab (especially for refractory cases) 2
  • OR Intravenous immunoglobulin (IVIG) for refractory cases 6, 2
• Immediate referral to multidisciplinary team including ophthalmology for ocular involvement

Monitoring and Follow-up

• Initial follow-up every 2 weeks until disease control
• Then monthly for 3 months, every 2 months thereafter
• Monitor for:
  • New lesion formation
  • Healing of established lesions
  • Treatment-related side effects
  • Disease progression to other mucosal sites 1

Treatment Goals and Definitions

• Control of disease activity: When new inflammatory lesions cease to form and established lesions begin to heal
• End of consolidation phase: No new lesions for at least 4 weeks and approximately 80% of inflammatory lesions healed
• Minimal therapy: Maintenance on low-dose medications (e.g., dapsone ≤1.0 mg/kg/day, prednisone ≤0.1 mg/kg/day, or minimal adjuvant therapy) 1
• Complete remission: Absence of new or established lesions while on minimal therapy for at least 2 months 1

Important Considerations

• Ocular involvement requires urgent ophthalmology consultation to prevent blindness
• Laryngeal involvement requires ENT evaluation to prevent airway compromise
• Esophageal involvement requires gastroenterology consultation to prevent strictures
• Patients with immune checkpoint inhibitor-associated MMP require permanent discontinuation of the immunotherapy 1
• Regular monitoring of complete blood count, liver and kidney function tests is essential during immunosuppressive therapy 5

Treatment Duration

Treatment typically continues for 4-12 months, with consideration for discontinuation when the patient is symptom-free for 1-6 months on minimal therapy 5. Relapses are common, requiring long-term follow-up.