直腸カルチノイド腫瘍（NET）ESD後に診断された梅毒性直腸炎の1例

A Case of Syphilitic Proctitis Diagnosed after Endoscopic Submucosal Dissection for a Rectal Neuroendocrine Tumor

要旨●患者は40歳代，男性．肛門部周囲の違和感精査で下部直腸（Rb）のカルチノイド腫瘍/神経内分泌腫瘍（NET）と診断され，内視鏡治療目的に当科紹介となった．内視鏡所見ではRbにびらんを伴う粘膜下腫瘍様隆起が多発しており，NETに対するESDと同時に施行された同部位からの生検および血清学的検査にて梅毒性直腸炎と診断した．梅毒性直腸炎に対してはベンジルペニシリンによる薬物療法を行った．梅毒性直腸炎の内視鏡像は多彩であり診断難易度が高い．直腸の非特異的な炎症や隆起性病変の鑑別において，本症を念頭に置くことが重要である．

　A man in his 40s was referred for endoscopic treatment of a rectal neuroendocrine tumor（NET）detected during evaluation of anal discomfort. Colonoscopy revealed multiple submucosal tumor-like elevations accompanied by erosions in the lower rectum. Based on endoscopic biopsy of these lesions and serological testing, the patient was diagnosed with syphilitic proctitis. He subsequently underwent endoscopic submucosal dissection for the rectal NET and received antibiotic（intravenous penicillin G）therapy for syphilitic proctitis. Endoscopically, syphilitic proctitis can present with diverse and nonspecific findings, making diagnosis challenging. Therefore, syphilitic proctitis should be considered in the differential diagnosis of nonspecific inflammatory or elevated rectal lesions.