図１〜図８の脾臓の病変↑は造影されない，すなわち血流のない部分で，中心部の図５で脾門部を頂点とする楔形となっており梗塞である．38度の発熱，心臓に収縮期雑音があり，不整脈がないことから細菌性心内膜炎からの感染性塞栓症（septic emboli）を疑うべきである．心エコーにて僧帽弁にvegetation形成，血培でブドウ球菌が検出され細菌性心内膜炎と診断された．3週間後に右腎梗塞を併発したので僧帽弁置換術が行われた．

参考症例（脾動脈瘤血栓による脾梗塞）：67歳男性．約15時間前急に心窩部痛があり，まもなく嘔気と数回の嘔吐を伴った．近医受診し鎮痛剤を筋注してもらったが腹痛は軽減せず救急搬送された．体温：36.0℃，腹部は心窩部に軽度の圧痛があるのみ．心電図で心房細動はない．　
脾梗塞（↑）の診断は容易であるが，発熱がなく，心房細動もないからその原因を脾臓の支配動脈にないか検索する．図３と図４の▲が脾門部の脾動脈瘤であり，造影されないので動脈瘤が血栓を起こし，その末梢が閉塞した結果梗塞を招いたと診断できればＥｘｐｅｒｔである．

文献考察１）：脾梗塞，病因は表１．
Hepatogastroenterology. 2001 Sep-Oct;48(41):1333-6.
A rare cause of acute abdomen: splenic infarction.
Hatipoglu AR, Karakaya K, Karagulle E, Turgut B.

Splenic infarction is a rare disorder. We have treated 4 patients during the last year. Abdominal pain in the left upper quadrant was the common complaint. Other complaints were fever, nausea and vomiting. Computed tomography showed infarcted areas in the spleen in all of the patients. Splenectomy was applied to three of the patients with recurring symptoms. The other patient had the first episode treated medically. Pulmonary embolism in one and surgical wound infection occurred in another patient during postoperative follow-up for nine (range: 4-14) months.PMID: 11677957
要旨：脾梗塞の病因は塞栓症（embolism）が最も多く38％，次いで血液疾患（hematological disorders）が29％．67％が腹痛で発症する．7〜14日で症状が消失する場合が多いが，20％に脾臓壊死，膿瘍形成，出血，破裂や嚢胞形成などの合併症を伴う．

文献考察２）：発熱を伴う脾臓の限局性病変（表２〜表４）
Singapore Med J. 2006 Jan;47(1):37-41.
Computed tomography of focal splenic lesions in patients presenting with fever.
Joazlina ZY, Wastie ML, Ariffin N.

INTRODUCTION: There is an awareness of the increased incidence of splenic abscess in Southeast Asia giving rise to unexplained fever. This study looks at the role of computed tomography (CT) in evaluating focal splenic lesions in patients presenting with fever. METHODS: 37 patients presenting with fever of unknown origin underwent CT and this study retrospectively analyses the findings in these patients. 13 patients also had associated abdominal pain. Patients with conditions at high risk for splenic infection include: diabetes mellitus in ten patients, leukaemia in seven patients, human immunodeficiency virus infection in five patients, intravenous drug abuse in six patients, and steroid therapy in two patients. No risk factors could be identified in seven patients. RESULTS: Splenic abscess was diagnosed in 28 patients. A range of infecting organisms was isolated but the most frequent were Staphylococcus aureus (eight), tuberculosis (four), Streptococcus (four), fungal (four) and melioidosis (four). No infecting organism could be identified in ten cases though in patients with leukaemia with multiple low attenuation areas, the cause was presumed to be fungal. Six patients were diagnosed to have splenic infarcts though differentiation from splenic abscess could be difficult; these patients were treated for an abscess and all had endocarditis. Three patients were subsequently diagnosed with lymphoma. Percutaneous abscess drainage was performed in five patients and splenectomy was carried out in six patients. CONCLUSION: CT proved to be very useful as it not only revealed the size and extent of any splenic abnormality but it assisted with guidance for percutaneous drainage, determined the site for biopsy, and provided follow-up after treatment.PMID: 16397719