Presentation
Lower abdominal pain. White cell count 11.9 (ref. 4.0-11.0). ?colitis ?diverticulitis.
Patient Data
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There is a saccular aneurysmal dilatation extending anterolaterally on the left side of the infrarenal abdominal aorta, with a neck of 2.2 cm (longitudinal), depth of 2.3 cm (transverse) and longitudinal extension of 3.5 cm. A thick fat stranding surrounds this vascular dilation and, contrasting to the remainder aorta, no atheromatous calcifications are present in its walls. Inferiorly in the abdominal aorta, a intimal flap with atheromatous calcification is identified crossing the center of the opacified aortic lumen and may represent a chronic dissection.
The liver, spleen, pancreas, kidneys and adrenal glands are normal. No abnormality of the bowel is identified. There is no free fluid or free gas.
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Selected images of the previous CT 5 days prior
Exams performed in the community 5 days prior to the presentation to the ED. Non-contrast images demonstrating the same saccular aneurysm, but with significantly smaller dimensions.
Case Discussion
The diagnosis of a mycotic aneurysm was achieved based on the imaging and clinical data. These aneurysms are caused by infection of the arterial wall, usually bacterial. It is a complication of the hematogenous spread of bacterial infection, classically from the heart.