Real-Time, Noninvasive Diagnosis of Bullous Pemphigoid: Diagnostic Performance of Line-Field Confocal Optical Coherence Tomography.

backgroundBullous pemphigoid (BP) is a common autoimmune blistering dermatosis often difficult to distinguish from other inflammatory conditions. Timely diagnosis is crucial for appropriate management. Line-field confocal optical coherence tomography (LC-OCT), a noninvasive imaging technique that uses an 800nm laser to generate high-resolution vertical and horizontal cross-sectional images of the skin, is evaluated as a diagnostic tool for BP. MATERIALS AND

methodsA prospective, single-center study was conducted on 26 patients with suspected BP. LC-OCT imaging, histopathology, and direct immunofluorescence (DIF) were performed. LC-OCT images were assessed for the presence of key diagnostic features, including subepidermal cleavage and eczema criteria.

resultsBased on histopathology, DIF, indirect immunofluorescence (IIF), and ELISA, the final diagnoses were 15 BP cases and 11 non-BP cases. LC-OCT correctly identified 12 of 15 BP cases and all 11 non-BP cases, demonstrating a sensitivity of 0.8 and a specificity of 1.0. The presence of subepidermal cleavage was a key diagnostic criterion for BP (p = 0.000). The absence of alternating hypo- and hyper-reflective layers (p = 0.000), thickened and disrupted stratum corneum (p = 0.014), spongiosis (p = 0.036), and thickened epidermis (p = 0.043), which occurred significantly less frequently in BP cases, further supported the diagnosis.

conclusionLC-OCT demonstrates high sensitivity and specificity in diagnosing BP, offering a rapid, point-of-care diagnostic approach. LC-OCT can be used to evaluate unclear inflammatory skin conditions and guide further investigations. However, LC-OCT has limitations in diagnosing non-bullous stages of BP; thus, histology and DIF remain the gold standard for definitive diagnosis.