Pemphigoid, Cicatricial

Description

• Cicatricial pemphigoid (CP) is a rare, chronic, acquired autoimmune subepithelial blistering disorder that mainly affects mucous membranes.
• In descending order of involvement, CP affects the oral cavity (85%), conjunctivae (65%), skin (20%), nasal cavity (15%), anogenital region (20%), pharynx (20%), larynx (10%), and esophagus (5%).
• Clinical hallmark of CP is scarring, which may result in serious functional impairment.
• Synonym(s): Brunsting-Perry CP (1); mucous membrane pemphigoid; oral pemphigoid; desquamative gingivitis; ocular CP; ocular pemphigus (incorrect nomenclature)

Epidemiology

• Average onset at age 60 to 80 years
• Rarely children can be affected, youngest found to be 10 months old (1).
• Female to male ratio of 2:1
• No racial or geographic predilection

Incidence
1/1 million annually

Etiology and Pathophysiology

• Autoantibodies binding to specific epithelial basement membrane components:
  • Type XVII collagen (bullous pemphigoid antigen 2), type VII collagen, laminin-5, laminin-6, α-6 and β-4 integrin subunits, 120-kDa undefined epithelial antigen
    • Exclusive ocular mucosal involvement: autoantibodies to β-4 subunit of integrin
    • Exclusive oral mucosal involvement: autoantibodies to α-6 subunit of integrin
    • Mucosal and skin involvement: autoantibodies to BP180
    • Association with internal malignancy: autoantibodies to anti–laminin-332 (1)
• “Epitope spreading”: Previous inflammatory events may predispose epithelial basement membrane components to autoreactive T cells.
  • Several patients with Stevens-Johnson syndrome developed CP.
  • Association with Sjögren syndrome and ocular CP
• Mechanism linking the binding of the antibodies to the epithelial basement membrane zone and subsequent scarring process yet to be defined

Genetics
Association with HLA DQB1*0301

General Prevention

None identified

Commonly Associated Conditions

Anti–laminin-332 autoantibody–positive (previously anti–laminin-5/epiligrin) patients have a higher risk of internal malignancy.