Childhood Bullous Pemphigoid with Atypical Immunopathology: A Case Series

Bullous pemphigoid (BP) is a rare autoimmune blistering disorder primarily affecting older adults, with limited occurrences in children. BP in children typically manifests as large, tense blisters on the skin, often on flexural areas. It also more often affects the oromucosal areas and the face in children than in adults. Diagnosis involves histopathological examination revealing eosinophilic spongiosis or subepidermal split, immunofluorescence tests highlighting immunoglobulin G (IgG) and C3 depositions, and immunological assays detecting BP180 and BP230 IgG autoantibodies. This report presents two cases of childhood BP (CBP) with atypical immunopathological findings. Clinically, the two cases had generalized plaques and bullae, including the face. The first case exhibited the characteristic linear deposits of IgG and C3 on the basement membrane through direct immunofluorescence (DIF) and revealed negative anti-BP180 antibodies on enzyme-linked immunosorbent assay (ELISA). In contrast, the second case showed negative DIF results, despite clinical suspicion, but had positive anti-BP180 IgG antibodies on ELISA. It is, therefore, crucial to consider the complete clinical presentation of the patient, in conjunction with the histological findings and immunopathologic assessments to diagnose CBP.