Histopathological Patterns in Bullous Dermatitis Artefacta: A Retrospective Case Series

Background: Dermatitis artefacta (DA) is associated with self-harming behaviors, which can be conscious or unconscious. It is characterized by lesions with atypical distributions and geometric patterns, produced by manipulation of the skin through friction, suction, heat, cold, electric current, or chemicals. Diagnosis is challenging, and there are no confirmatory tests, but histology can provide important clues for identifying artificial causes. Objective: Our aim was to retrospectively review histological characteristics and anatomopathological patterns in patients with bullous DA. Methods: We performed a retrospective chart review of patients with a diagnosis of bullous DA. Patients with self-induced skin diseases related to other psychic causes (such as anxiety, depression, or obsessive-compulsive disorder) were excluded. Fifteen cases were analyzed between 2009 and 2024. Biopsies were submitted to histological analyses using different techniques including hematoxylin–eosin, periodic acid–Schiff, and direct immunofluorescence, with investigation of IgA, IgM, IgG, and C3. Results: Histopathology showed 4 main patterns: subepidermal blisters with neutrophils, spongiotic blisters with sparse necrotic keratinocytes, dermoepidermal or mixed cleavage blisters with follicular compromise, and “erythema-multiforme–like” blisters with extensive necrosis. Conclusions: Dermatologists are uniquely positioned to diagnose and manage DA. Nevertheless, when clinical diagnosis is inconclusive, recognition of these histopathological patterns may provide valuable diagnostic clues for dermatopathologists evaluating biopsies from patients with suspected DA.