C-0702 Conservative management of abdominal aortic stent-graft infection. Aims and objectives. The treatment of abdominal aortic aneurism, availability and durability of stent-graft materials has revolutionized the management of patients with abdominal aortic stent-graft infection. This technique is not free of complications and the infection is the most dreaded. Our purpose is to describe our experience in the conservative management of abdominal aortic stent-graft infection, the imaging findings after treatmen and a litetature review. Methods and materials. Prospective, evolutionary and surveillance study of conservative management of stent-graft infections in four patients. Diagnosis was based on clinical, microbiology parameters and image studies. Conservative management included: Fine needle aspiration puncture (FNAP) with or without percutaneous drainage with urokinase infusion and intravenous antibiotic therapy without stent-graf removal. We value the presence of aorto-enteric fistula, concomitant infection, time from stent placement and associated treatments. Results. Patient 1: 64 year-old patient with vascular risk factors (hypertension, dyslipidemia and smoking habits) and abdominal aortic aneurysm excluded by stent-graft in May 2013 requieres medical attention for bilateral inguinal pain, malaise and myalgia. CT performed revealed signs of infected abdominal aortic aneurysm (endoluminal air bubbles, reactive lymphadenopathy and subtle periaortic fat stranding). PET-CT showed focal captation area over left psoas (fig.1).
A conservative management with antibiotic therapy was implanted and clinic and analytic parameters improved during the hospital stay. However, a few days later, his clinical status got worse and a new CT scan revealed progression in the size of the aneurysms and involvement of the left psoas (fig.2). In view of this situation, an ultrasound guided puncture and catheter drainage placement were performed over the left psoas abscess. CT control scan revealed decreasing size of the abscess (fig.3).
Same attitude was adopted with the aortic aneurysm; a 8.5F catheter was placed into it with the patient on prone position and 200 cc of purulent material was drained (fig.4). The patient outcome was satisfactory and posterior CT studies showed marked decrease in the aneurysm sac size (fig.5 and fig.6).
Patient 2: 80 year-old patient with hypertension, ischemic cardiomyopathy and smoking habits, is diagnosed of abdominal aortic aneurysm in April 2013 on CT performed in clinical context of back pain. Aneurysm exclusion by EVAR is performed on May 3, 2013. Three months later the patient suffered nightly abdominal pain and fever. CT revealed a larger aneurysmal sac with thickened aortic wall and small peripheral abscesses with hypermetabolic activity on PET-CT (fig.7). This patient underwent an echocardiography study with final diagnosis of infective endocarditis; antibiotic therapy was established, with consequent clinical and analytical improvement. CT performed a month later revealed aneurysmal sac enlargement and increasing peripheral collections with extension to the left psoas (fig.8).
In this context, a direct punction of the aneurismatic sac was performed and a percutaneous catheter drainage was placed by interventional radiology; 30 cc of hematic exudate was obtained during the procedure and 220 cc after two days (Fig.9, images above). Despite of the drainage, CT performed a few days later showed no morphological changes on the aneurysm size (Fig.9, images below), and thus, an Urokinase therapy was established along three consecutive sessions; with this treatment 400 cc of exudative marerial was drained. There was important clinic and analytic parameters improvement and the patient was discharge from the hospital (Fig.10).
Patient 3: 76 year-old patient with atrial flutter, chronic renal failure on dialysis and abdominal aortic aneurysm excluded by stent-graft in May 2005. The patient presented fever without a source in December 2011. CT revealed important infra-renal abdominal aortic aneurysm (máximum diameter of 75 mm) with thickened aortic wall, findings highly suggestives of infection (Fig.11). This patient underwent antibiotic therapy with significative improvement and additional interventional procedures were not considered (Fig.12 and Fig.13). Currently, the patient is clinically stable.
Patient 4: 71 year-old patient is admitted to hospital in 2010 because of epigastric pain and upper gastrointestinal (GI) bleeding. Upper GI endoscope was performed and active bleeding was identified. Urgent CT (Fig.14, images above) revealed an infrarrenal aneurysm (45 mm of diameter) and indirect signs of aortoenteric fistula. The aneurysm was excluded by EVAR (Fig.14, images below) and the patient was admitted to the intensive care unit under antibiotic therapy.
Despite of an initial improvement, the patient clinically got worse and new CT scan was performed (Fig.15). A fine needle aspiration puncture was nondiagnostic and the patient continued with antibiotic treatment (Fig.16) with clinical improvement since then.
Summary: Four patients were diagnosed of stent-graft infection. Two of them received antibiotic therapy after the diagnosis with blood cultures and FNAP of the aneurysm sac. Two other men were at high risk because of early endograft infection and aorto-enteric fistula. The first one was treated by placing a catheter drainage, instillation of diluted urokinasa and heparin in three sessions. On the other one, we performed FNAP with a drainage catheter emplacement. Both aneurismatic sacs decreased in size and the patients continued with antibiotics. All patients improved their clinical parameters and clinically. David Uceda Navarro. H.U. Dr. Peset. Valencia.