Linear IgA bullous dermatosis associated with immunotherapy

Area of Science:

• Dermatology
• Immunology
• Oncology

Background:

• Linear IgA bullous dermatosis (LABD) is a rare autoimmune blistering disease.
• Its clinical presentation can mimic bullous pemphigoid (BP).
• Immunotherapy-induced BP is documented, but LABD is rarely associated with immunotherapy.

Observation:

• A 67-year-old woman with metastatic ovarian cancer developed pruritic tense bullae after receiving anti-PD1 and anti-CTLA4 immunotherapy.
• Histopathology revealed subepidermal blisters with neutrophils (H&E) and linear IgA deposition (direct immunofluorescence).
• The patient's condition was diagnosed as LABD.

Findings:

• LABD developed secondary to immunotherapy in this patient.
• Initial prednisone treatment was ineffective.
• Dapsone therapy led to rapid resolution of blisters.

Implications:

• This case underscores the importance of considering LABD in patients on immunotherapy presenting with blistering disorders.
• Accurate diagnosis using H&E histology and direct immunofluorescence is critical.
• Prompt initiation of appropriate treatment, such as dapsone, can effectively manage immunotherapy-induced LABD, potentially avoiding treatment discontinuation.