Role of IgE in Bullous Pemphigoid: A Case Report

Abstract

Background: Bullous pemphigoid is an autoimmune subepidermal blistering disorder that may be preceded by a non-bullous phase characterised by intense pruritus and urticarial lesions. Immunoglobulin E and eosinophils have been implicated in its inflammatory response and may contribute to pruritus and tissue injury. Case Presentation: A 64-year-old man with systemic arterial hypertension and heart failure who was receiving bisoprolol, furosemide, spironolactone, and empagliflozin developed generalised pruritus and urticarial plaques, followed by tense bullae and extensive erosive lesions predominantly involving the trunk and upper limbs. Serum IgE was elevated at 570 IU/mL. Histopathological examination demonstrated a subepidermal blister containing fibrin and inflammatory cells, including eosinophils, together with a mixed dermal inflammatory infiltrate. The clinical and histopathological findings supported a diagnosis of bullous pemphigoid. Treatment with systemic prednisone and azathioprine was initiated, with partial clinical improvement after two months and a reduction in serum IgE to 234 IU/mL. Diuretic therapy was referred for cardiological reassessment. One week after the follow-up evaluation, the patient experienced a massive myocardial infarction and died. Conclusion: This case illustrates the diagnostic difficulty posed by the pruritic and urticarial phase that may precede blister formation in bullous pemphigoid. An elevation and subsequent reduction in total serum IgE were observed during the clinical course; however, these findings should be interpreted alongside clinical and histopathological features rather than as disease-specific diagnostic evidence.