Esophageal intramural pseudodiverticulosis in mucous membrane pemphigoid: Potential diagnostic utility of C4d immunohistochemistry

摘要

Dear Editor: A 55-year-old man presented for re-evaluation of an undetermined cervical esophageal stricture. The patient had undergone Savary bougienage 4 years and 1 month before. Upper endoscopy revealed tubular narrowing in the proximal esophagus, however, without circumscript strictures. Yet, tiny erythematous maculae and some flask-like outpouchings characteristic of intramural pseudodiverticulosis (EIPD) were observed (Fig. 1A). Moreover, discrete scarring and patchy erosions, in part, accompanied by mucosal desquamation were detected throughout the esophagus (Fig. IB), raising suspicion of underlying autoimmune blistering disease. Specialized der-matopathological evaluation demonstrated smooth subepithelial detachment along with a non-specific inflammatory infiltrate, consistent with mucous membrane pemphigoid (MMP) (Fig. lC).This was supported by direct immunofluorescence demonstrating linear basal immunoglobulin G and complement 3c depositions. Of interest, immunohistochemistry against complement fragment d4 (C4d) likewise confirmed aberrant complement activation(Fig. 1D). Consistently, serological evaluation was positivefor the 180-kD bullous pemphigoid antigen (BP180) with negative findings for BP230, laminin 5 and α6β4 integrin. Comprehensive clinical work-up yielded no indication of other organ involvement. Given the final diagnosis of esophageal MMP, immunosuppressive therapy with azathioprine resulted in complete endoscopic and histopathological remission (Fig. 1E,F).