・ TAKAHASHI Shin-ichi 3 ) ・ KATAKURA Akira 4 ) : Herein we describe the case of a 59-year-old woman with a history of pemphigus foliaceus (PF) , but no skin lesions. She was referred to our department for further evaluation of gingival erosion. A histopathological examination of the areas of erosion showed basal cells with cleft formation and acantholysis. Direct immunofluorescence of the affected regions revealed deposition of IgG and C3 between epithelial cells. These findings were consistent with those of mucosal dominant pemphigus vulgaris. However, only desmoglein (Dsg) 1 was positive, and Dsg 3 was negative on immunoserological testing, which are atypical results. The erosion in the oral cavity was associated with only slight pain, and corticosteroid ointment was prescribed. Approximately 5 months after the treatment, the oral cavity symptoms had disappeared, but several small blisters appeared on the skin of the back. At this point, anti-Dsg 1 Ab levels were elevated. Histopathological and direct immunofluorescence findings suggested recurrent PF. The skin symptoms continued to recur and abate, but the oral cavity symptoms have not recurred. We described a case of anti-Dsg 1 Ab-positive pemphigus in which oral lesions appeared after skin symptoms had disappeared, followed by the reappearance of skin lesion. This case demonstrates that patients with pemphigus sometimes, albeit rarely, exhibit autoantibody profiles that do not reflect the Dsg compensation theory. In such cases, macroscopic, histopathological, and direct immunofluorescence findings are considered important for diagnosis. : pemphigus vulgaris (尋常性天疱瘡) ， anti-desmoglein antibodies (抗デスモグレイン抗体) ， direct immunofluorescence (蛍光抗体直接法) 1) 東京歯科大学オーラルメディシン・口腔外科学講座 (主任：野村武史教授) 2) 東京歯科大学市川総合病院臨床検査科病理 (主任：田中陽一教授) 3) 東京歯科大学市川総合病院皮膚科 (主任：高橋愼一教授) 4) 東京歯科大学口腔病態外科学講座 (主任：片倉 朗教授) 1)
