高齢者非腫瘍性疾患の特徴―急性出血性直腸潰瘍

The Clinical Features of Non-neoplastic Disease on the Elderly─Acute Hemorrhagic Rectal Ulcer

要旨　急性出血性直腸潰瘍は，寝たきり状態の高齢者が突然に無痛性の大量出血を呈し，下部直腸に全周性の潰瘍が確認される特徴的な臨床像を示す救急疾患である．直腸の病変は，内視鏡を直腸内で反転しないと全体像が観察困難な歯状線直上に局在し，動脈硬化を背景に，仰臥位寝たきり状態となることで下部直腸粘膜血流量が減少し惹起される．治療では主に内視鏡的止血術が行われるが，側臥位への体位変換も再出血予防や治癒期間の短縮に有用である．代表的な鑑別疾患として宿便性潰瘍とNSAID坐剤起因性直腸病変が挙げられるが，サイトメガロウイルス直腸炎にも注意が必要である．

　Acute hemorrhagic rectal ulcer is one of emergency diseases in lower digestive tract. The clinical features is the sudden indolent massive bleeding on bed-ridden elderly patients. The endoscopic findings are characterized by the circumferential ulcer which was situated in the terminal rectum immediately proximal to the dentate line. The etiology of the rectal ulcer is the significant decrease of the mucosal blood flow in the lower rectum caused by changing lying position. The endoscopic hemostasis is the first selection of medical therapy for AHRU. The lateral position is also helpful for the avoidance of re-bleeding and the shortening of ulcer healing. Stercoral ulcer, rectal lesions induced by NSAID suppositories and CMV rectal ulcers are important as the differential diagnosis for AHRU.