上腸間膜動脈のmycotic aneurysmによって回腸出血性梗塞を惹起した1剖検例

Ileal Hemorrhagic Infarction Due to Complete Obstruction of Superior Mesenteric Artery Associated with Mycotic Aneurysm, Report of an Autopsy Case

　腸循環障害性病変は近年，増加の傾向にある．特に慢性腎不全や敗血症のごとく全身状態の不良な患者に原因不明の消化管出血が，ときに認められるが，その原因の1つにmycotic aneurysmがある．

　われわれは慢性腎不全患者で消化管出血を来し，上腸間膜動脈のmycotic aneurysmによって惹起された区域性の腸循環障害性病変を経験したので報告し，この病態への注意を喚起したい．

　症　例

　患　者：66歳，女．

　主　訴：下血．

　既往歴：15歳および25歳のときに肋膜炎．

　現病歴：1977年（64歳）ごろから眼瞼浮腫が出現し，同年11月には近医にて腎疾愚を指摘されて，1カ月間入院治療を受けた．

　1978年頭初から全身倦怠感，眼瞼浮腫および視力低下が出現し，同年8月に北里大学病院を受診した．

　1978年9月8日には本院で慢性腎不全と診断され，第1回目の入院をした．血液透析を行うも心不全出現のために腹膜透析に変更し，以後の1週間に3回の透析を行った．

　1979年3月17日には某病院へ転院し，透析を週4回行っていたが，同年8月30日ごろから腹膜透析の排液が軽度の混濁を示してきた．そのために，腹膜透析用の溶液に抗生剤を注入し，透析を続けた．

　同年9月4日から赤黒色便が出現し，翌日になっても下血が持続したために，sigmoidoscopyが施行されたが，出血部位は判明せず，9月6日には北里大学病院へ転院となった．

　A 66 year-old housewife suffering from chronic renal failure was admitted to Kitasato Hospital on September 14, 1979, with a history for two days of tarry stools. On admission, physical examination revealed a pale edema of eyelids and cardiac enlargement with systolic murmur. Blood pressure was 118/72, pulse regular, and body temperature was 36.6℃. Pertinent positive physical finding were limited to intestinal hemorrhage. We could not find any cause of intestinal hemorrhage in spite of several endoscopical examination and intestinal barium enema. Intestinal hemorrhage continued.

　On the selective angiography, superior mesenteric artery showed complete obstruction at the base and the vasculature of small intestinal wall was altered and small in size and showed poor blood supply from inferior mesenteric branches and middle colic artery through dorsopancreatic arcade from truncus celiac. The patient became gradually drowsy and got worse because intestinal hemorrhage could not be controlled by conventional therapy.

　Blood pressure was not improved to normal level two weeks before death. Autopsy was performed three hours after death on November 14, 1979, because of massive intestinal hemorrhage and cardiac failure due to digital toxication. Generalized atherosclerosis was marked in the kidneys and abdominal aorta. Especially the orifice of the superior mesenteric artery showed complete obstruction macroscopically.

　Small intestinal wall was moderately thickened and anemic in almost the entire length. It was suggestive of chronic blood insufficiency like angina pectoris of the heart. The surface of the small intestinal mucosa was anemic with focal hemorrhage without edema. New, massive intestinal hemorrhagic necrosis was observed in segmental ileal region about 40 cm in length, beginning from 39 cm proximal from the ileocecal valve. The mesentery of this segment was also strikingly thickened and edematous with petechial hemorrhage and when sectioned, thrombi extruded from the cut ends of the ileal branch but no arterial ballooning. Pathological examination confirmed hemorrhagic infarction of the small bowel and thrombi of the mesenteric artery associated with mycotic aneurysm without rupture.

　We should notice mycotic aneurysm when a patient has a concomitant intestinal hemorrhage with severe renal failure and sepsis.