Non-Pemphigoid Subepidermal Blistering Disorders: Practice Pearls to Maximize Direct Immunofluorescence Yield

Conclusions

• Epidermolysis Bullosa Acquisita (EBA) is a rare autoimmune blistering disorder characterized by autoantibodies against collagen 7.
• Direct immunofluorescence (DIF) is critical in diagnosing EBA, highlighting IgG and C3 deposits along the basement membrane zone.
• Identifying a U-shaped serration pattern on DIF can enhance diagnostic yield for EBA.
• Bullous systemic lupus erythematosus can present similarly to EBA and is diagnosed mostly through serological studies rather than histological findings.
• Linear IgA bullous disease is another autoimmune blistering disorder with distinct clinical forms including chronic and drug-induced variants.
• Dermatitis herpetiformis is linked to celiac disease and shows characteristic IgA deposits in a granular pattern on DIF.
• Broad shave biopsies and salt-split studies can increase diagnostic yields in cases of autoimmune blistering disorders.
• Clinical presentations can vary in pediatric EBA, often mimicking other conditions like linear IgA bullous disease, necessitating careful DIF evaluation.
• In autoimmune blistering disorders, eosinophilic infiltrates may occur, indicating that clinical and histological features must be interpreted together.