Mycotic aneurysm of the right iliac artery: imaging diagnosis and correlation with pathological findings

Abstract

Infectious aneurysms are almost invariably of bacterial origin. It is a rare life-threatening disease, with a mortality reaching 67% in the absence of an early treatment (1), due to hemorrhage and uncontrolled sepsis.Clinical and biological findings are not specific and the diagnostic is often delayed. In the presence of fever and sepsis, CT is the imaging method of choice as several features may indicate the infectious origin and distinguish from atherosclerotic aneurysms. Case reportA 55-year-old woman was admitted in our institution because of fever and abdominal pain.Upon admission, she presented with tachycardia (110 bpm) and slightly decreased blood pressure (110/70 mmHg). Infection of the lower urinary tract was suspected at first. Blood tests showed an important inflammatory syndrome with increased C-reactive protein (CRP) levels (34 mg/dL, normal: < 1 mg/dL). However, urine analysis did not disclose any abnormal findings. A CT-scan of the whole abdomen was performed (Fig. 1).CT revealed an important infiltration of the retroperitoneal fat surrounding the distal part of the abdominal aorta as well as the proximal portion of the right iliac artery. The density of the infiltrated fat was evaluated at 20 HU, which was hardly compatible with blood. The infiltration also involved the pelvic retroperitoneal space. After contrast artery and measured 44 x 31 mm in axial view. Based on these clinical and radiological findings, the diagnosis of infected aneurysm of the right iliac artery was rendered. The patient was surgically treated 3 days after admission. She is alive and doing well 2 years after the operation. injection (Fig. 2), CT demonstrated a large aneurysm that was located in the proximal part of the right iliac JBR-BTR, 2012, 95: 350-354. MYCOTIC ANEURYSM OF THE RIGHT ILIAC ARTERY: IMAGING DIAGNOSIS AND CORRELATION WITH PATHOLOGICAL FINDINGSG

Vascular Graft Infections, Mycotic Aneurysms, and Endovascular Infections: A Scientific Statement From the American Heart Association

“…191,219 However, the majority of studies suggest that absence of calcium is more often seen in MA than in atherosclerotic aneurysms. 9,125,163,192 Mural thrombi were reported more frequently with atherosclerotic aneurysms than with MAs.…”

“…Table 5 shows findings on CTA that are helpful for the diagnosis and management of aortic MA. 148,163,191,192,219 The typical appearance is a saccular aneurysm with an by guest on May 9, 2018 http://circ.ahajournals.org/ Downloaded from irregular lobular contour. Absent or minimal calcification is suggestive of MA.…”

“…The average age is >65 years, and there is a strong association with cigarette smoking and diabetes mellitus. Eight-five percent of atherosclerotic aortic aneurysms are located in the infrarenal segment, 148,[192][193][194][195] whereas most aortic MAs are located in the suprarenal portion of the aorta. 148,[192][193][194][195] Thoracic MA is often associated with recent reconstructive aortic surgery, IE, or prosthetic valve endocarditis.…”

“…148,[192][193][194][195] Among 640 renal transplant recipients over 8 years at the University of Minnesota, 8 (1%) developed MAs, and 6 of these 8 occurred in the external iliac artery. 105 …”

“…Data derived from Chen et al, 148 Lee et al, 163 Macedo et al, 191 Colin et al, 192 and Lin et al clInIcal stateMents anD GuIDelInes agement should be individualized for each patient and should be executed via a team approach that involves experts in vascular diseases and surgery, cardiology and cardiovascular surgery, diagnostic and interventional radiology, critical care medicine, infectious diseases, and microbiology in a facility with access to these experts and services on an emergency basis.…”