Predicting Infection Related Complications After Endovascular Repair of Infective Native Aortic Aneurysms.

OBJECTIVE: Endovascular aortic repair (EVAR) as surgical treatment for infective native aortic aneurysm (INAA) is associated with superior survival compared with open surgery, but with the risk of infection related complications (IRCs). This study aimed to assess the association between baseline clinical and computed tomography (CT) features and the risk of post-operative IRCs in patients treated with EVAR for INAA. It also sought to develop a model to predict long term IRCs in patients with abdominal INAA treated with EVAR. METHODS: All initial clinical details and CT examinations of INAAs between 2005 and 2020 at a major referral hospital were reviewed retrospectively. The images were scrutinised according to aneurysm features, as well as peri-aortic and surrounding organ involvement. Data on post-operative IRCs were found in the patient records. Cox regression analysis was used to derive predictors for IRCs and develop a model to predict five year IRCs after EVAR in abdominal INAA. RESULTS: Of 3 780 patients with the diagnosis of aortic aneurysm or aortitis, 98 (3%) patients were treated with EVAR for abdominal INAAs and were thus included. The mean follow up time was 52 months (range 0 ‒ 163). The mean transaxial diameter was 6.5 ± 2.4 cm (range 2.1 ‒14.7). In the enrolled patients, 38 (39%) presented with rupture. The five year IRC rate in abdominal INAAs was 26%. Female sex, renal insufficiency, positive blood culture, aneurysm diameter, and psoas muscle involvement were predictive of five year IRC in abdominal INAA after EVAR. The model had a C-index of 0.76 (95% CI 0.66 - 0.87). CONCLUSION: Pre-operative clinical and CT features have the potential to predict IRC after endovascular aortic repair in INAA patients. These findings stress the importance of rigorous clinical, laboratory, and radiological follow up in these patients.

Mycobacterium Bovis Causing Mycotic Aneurysm Secondary to Intravesical Treatment with Bacillus Calmette-Guérin: A Case Report.

BACKGROUND: Bacillus Calmette-Guerin (BCG) is a live, attenuated strain of Mycobacterium bovis that is used in the treatment of non-muscle invasive bladder cancer (NMIBC). Vascular complications, including mycotic aneurysms, after BCG therapy are exceedingly rare. In this patient population, the diagnosis of mycotic aneurysms can be delayed or missed due to their non-specific clinical and radiologic presentation. Literature review reveals management of mycotic aneurysms attributable to BCG therapy is widely varied.2,5-8,12,15 CASE REPORT: We report a patient who presented with mycotic aneurysm formation secondary to BCG treatment for bladder cancer that was repaired with in-line reconstruction utilizing cryoartery and buttressed with omental flap. We suggest this as an alternative treatment to in-line prosthetic graft or extra-anatomic reconstruction.

Open versus endovascular repair of primary infected thoracic and abdominal aortic aneurysms.

OBJECTIVE: Primary infected aortic aneurysms are life-threatening if not treated promptly, but still possess a high mortality rate following open repair. The goal of treatment is to prevent rupture and clear infection. An endovascular approach is accepted as a bridge to definitive open repair. Our study compares the outcomes of endovascular versus conventional open repair of infected aortic aneurysms. METHOD: A single-center retrospective review was conducted of data from January 2012 to December 2021. Patients were categorized into three cohorts according to aortic involvement: thoracic aortic aneurysm (TAA), thoracoabdominal aortic aneurysm (TAAA), and abdominal aortic aneurysm (AAA). The primary endpoint was survival rate and the assessment of any associated factors. RESULT: Ninety-nine patients presented with infected aortic aneurysms. Of the 56 patients who presented with infected TAA, 38 patients underwent thoracic endovascular aortic repair and 18 patients underwent open TAA repair. Forty patients presented with infected AAA, of which 21 patients underwent endovascular aortic repair and 19 patients underwent open repair. Three patients presented with infected TAAA and all underwent open repair. The mean age was 67 years (range 33-88); 74 patients (74.8%) were men and 71 patients (71.7%) had immune dysfunction. Mean follow-up time was 24 months in the endovascular repair group and 38 months in the open repair group. The probability survival rate in the endovascular repair group was 86%, 86%, 77% and 51% at 1 year, 2 years, 5 years and 10 years, respectively, and in the open repair group this was 81%, 81%, 76%, and 64% at 1 year, 2 years, 5 years and 10 years, respectively. CONCLUTIONS: Endovascular repair for primary infected aortic aneurysms plays an important role in current practice as an alternate to open surgery or used as bridging to definitive open surgical repair. No significant difference was observed in either short- or long-term survival in patients with infected aortic aneurysm undergoing open or endovascular repairs.

Midterm outcomes of endovascular treatment for infected aortic aneurysms: Single center experience.

OBJECTIVE: The standard treatment of infected aortic aneurysms is open surgical repair but mortality rates remain high with the common cause of death being sepsis. Endovascular treatment of infected aortic aneurysms is another option and here we report the midterm outcomes of endovascular treatment for infected aortic aneurysms. METHODS: Thirty-four patients with infected aortic aneurysms underwent endovascular and hybrid repair between December 2012 and June 2021. The patients were evaluated for early and midterm outcomes including postoperative mortality, morbidity, recurrent aortic infection, and midterm survival. RESULTS: There were 34 patients who presented with infected aortic aneurysms with a mean age of 66.7 years (range, 26-89). Most of the patients presented with abdominal pain (94.1%) and fever (50.0%). The rate of positive blood culture for organisms was 32.4%. Salmonella was the most common organism. The procedures for treatment were endovascular repair using straight endograft, aorto-uni-iliac (AUI) endograft, bifurcated endograft, and thoracic endograft. Other procedures were endovascular repair with sandwich technique, chimney or periscope technique, and hybrid operation. The rate of in-hospital mortality and morbidity were 11.8% and 17.6%, respectively. Mean follow-up time was 21 months (range, 1-70). During the follow-up period, 7 (23.3%) patients had recurrent infection of aortic aneurysms and 5 patients required reoperation. Four patients died from septicemia and one patient died from cardiac disease. Male patients were more likely to have recurrent infection compared to females. The cumulative survival at 1 year and 2 years were 86.3% and 80.5%, respectively. CONCLUSION: In this retrospective review of the endovascular treatment in the patients who presented with infected aortic aneurysms showed acceptable early and midterm outcomes.

Rapid Progression of Aortitis Caused by Methicillin-Sensitive Staphylococcus Aureus in a Patient With Pneumonia: A Case Report.

Infected aortic aneurysm is a rare but fatal disease that occurs through various mechanisms. In this report, we describe the case of a patient who was hospitalized for acute pneumonia and developed an infected aortic aneurysm in the descending aorta during the hospitalization. A 73-year-old Japanese man presented to the emergency department with a chief complaint of fever. He had a history of chronic renal failure due to nephrosclerosis and was on regular hemodialysis three times a week. The patient presented with an elevated inflammatory response, anemia, and low platelet counts after various tests. Computed tomography (CT) showed ground-glass opacity in the left lung with a small amount of pleural effusion, leading to a diagnosis of pneumonia. The patient was admitted to the hospital on the same day, and a course of antibiotics (ceftriaxone [CTRX]) was started. On the fourth day of hospitalization, methicillin-susceptible Staphylococcus aureus (MSSA) was detected in the blood sample, which was collected from the patient on the day of admission. The patient was treated for MSSA pneumonia and bacteremia, and the antibiotics were changed to cefazolin (CEZ). Treatment with antimicrobials resulted in a negative blood culture retest on day 5 and improvement of the inflammatory response. On the 12th day, improvements in pneumonia and pleurisy were observed on the CT scan; however, an abnormal bulge was seen on the dorsal side of the descending thoracic aorta with suspected partial vessel wall disruption, suggesting a ruptured infected aortic aneurysm. Despite treatment with antibiotics, the thoracic descending aortic aneurysm continued to dilate with progressing rupture, and the patient died on the 25th day of hospitalization. This is the first report of an infected aneurysm caused by Staphylococcus aureus, despite a negative blood culture. Patients at high risk might develop infected aneurysms, and the possibility of rapid dilation should always be considered.

Infected Aortic Aneurysm Secondary to Pyogenic Flexor Tenosynovitis from Streptococcus pyogenes.

Infected aortic aneurysms are rare, and have a high mortality rate. Although not a major pathogen, Streptococcus pyogenes has been reported to cause infected aortic aneurysms. In the present case, the patient was hospitalized for pyogenic flexor tenosynovitis with S. pyogenes bacteremia. Despite drainage of the abscess around the flexor tendon and effective antimicrobial therapy, infected aneurysms developed in the abdomen and ascending aorta. Because of their rapid enlargement, these aneurysms were treated with in situ reconstruction. Although rare, the possibility that S. pyogenes is the causative pathogen of infected aortic aneurysms should be considered.

Infectious Aortitis Due to Salmonella Species Masquerading as Lung Malignancy.

Infectious aortitis is a rare but devastating vascular infection with mortality exceeding 40%. Early diagnosis is crucial but often hampered by radiographic mimickers. We report a patient who was thought to have lung cancer but ultimately found to have an infected aortic aneurysm and bacteremia owing to Salmonella species. Owing to surgical contraindications, he was treated palliatively with an initial regimen of intravenous ampicillin/sulbactam followed by lifelong oral antibiotic suppression. He ultimately rejected his diagnosis, discontinued medications, and was lost to follow-up. (Level of Difficulty: Intermediate.).

Helicobacter cinaedi Infections in Emergency Departments: A Descriptive Study.

AIM: Helicobacter cinaedi, a Gram-negative spiral bacterium, is a rare cause of bacteremia in humans. Unfortunately, little is known about H. cinaedi infections in emergency departments (EDs). We aimed to describe the clinical features of H. cinaedi infections in the ED. METHODS: We conducted a descriptive study at the ED of Kobe City General Hospital (KCGH) in Japan between November 2011 and December 2020. We included all ED patients with H. cinaedi infections. We retrospectively obtained the patient data from electronic medical records and described the patient characteristics, clinical course, and management of H. cinaedi infections. RESULTS: A total of 22 patients in the ED were diagnosed with H. cinaedi infections, and all of them were detected through blood cultures. The chief complaints were vague: fever (18/22, 81.8%), chills (10/22, 45.5%), and localized pain or tenderness (8/22, 36.4%). Patients with complicated cases were also reported in the ED; three patients had vertebral osteomyelitis, two had infected aortic aneurysms, and another two had infected cysts (renal cyst and pancreatic cyst with concomitant empyema). Tetracycline (minocycline) was primarily prescribed and administered intravenously in five of 15 (33.3%) and orally in nine of 20 (45.0%) patients. Only one (4.5%) patient required surgical interventions. None of the patients died in the hospital. CONCLUSIONS: We reported the clinical features of H. cinaedi infections in the ED. Although some patients developed complicated infections, the prognosis was not poor under appropriate treatment, and most of them were successfully treated with antibiotics, primarily tetracycline.

Group B streptococcus mycotic aneurysm of the abdominal aorta: report of a case and review of the literature.

Mycotic aneurysm of the aorta is an uncommon condition, and Group B Streptococcus (GBS) is exceedingly rare in this setting. We present the first reported case of a GBS-infected abdominal aortic aneurysm (AAA) in North America. Key clinical and imaging findings and pathologic correlation are highlighted. A relevant review of the literature is discussed, which will bring the reader up to date with this specific disease entity.

18-Fluorodeoxyglucose positron emission tomography in the diagnosis of prosthetic aortic graft infection: the difference between open and endovascular repair.

OBJECTIVES: 18-Fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) has been reported as useful for diagnosing aortic graft infection. However, 18F-FDG uptake may depend upon various factors including open versus endovascular repair and time from surgery. We aimed to elucidate the factors influencing its uptake and the diagnostic value of 18F-FDG PET/CT after open and endovascular repair. METHODS: Hospital database of PET/CT (N = 14 490) and our departmental database were cross-checked to identify those who underwent 18F-FDG PET/CT after aortic repair. Patient's data were retrieved from the chart. Images were reviewed by 2 nuclear medicine specialists in consensus, and the presence of increased 18F-FDG uptake was recorded. The maximum standardized uptake value (SUV max) was measured. RESULTS: Among the 1112 patients who underwent aortic repair between 2011 and 2022, 71 patients were identified. Eighteen patients underwent 18F-FDG PET/CT for suspected graft infection and the remaining 53 patients for other purposes (malignancy, etc.). Fourteen patients were treated as aortic graft infection. They had significantly higher SUV max than those without graft infection [mean 8.64 (standard deviation 2.78) vs 3.40 (standard deviation 0.84); P < 0.01]. In the non-infected grafts, SUV max was higher early after open surgical repair, while it remained low after endovascular repair. CONCLUSIONS: After endovascular aortic repair, a constant cut-off value of 'SUV max = 4.5' seems appropriate for diagnosing graft infection, since it remains low and stable from the early postoperative period. After open surgical repair, it seems acceptable to have 'stepwise cut-off value' depending on the time from surgery.

A minimally invasive approach to the infected aorta with novel endovascular use of biocomposite antibiotic material.

We have presented the case of a symptomatic, primarily infected aortic pseudoaneurysm treated with endovascular stent graft exclusion and adjunctive use of a long-acting biocomposite antibiotic material injected directly into the pseudoaneurysm sac. We have described preparation of the biocomposite antibiotic material and the catheter-directed delivery technique in detail. Although the use of long-acting antibiotic materials such as antibiotic beads has been well described when performing open surgery in an infected field, the application of these materials in endovascular procedures has been less certain. The techniques we have described have the potential to promote field sterilization in a minimally invasive manner for patients with aortic infections who could be poor candidates for open surgery.

Features of infective native aortic aneurysms on computed tomography.

BACKGROUND: Infective native aortic aneurysm (INAA) is a rare clinical diagnosis. The purpose of this study was to describe the CT findings of INAAs in detail. METHODS: This was a retrospective single-center study of INAA patients at a major referral hospital between 2005 and 2020. All images were reviewed according to a protocol consisting of aneurysm features, periaortic findings, and associated surrounding structures. RESULTS: One hundred and fourteen patients (mean age, 66 years [standard deviation, 11 years]; 91 men) with 132 aneurysms were included. The most common locations were infrarenal (50.8%), aortoiliac (15.2%), and juxtarenal (12.9%). The mean transaxial diameter was 6.2 cm. Most INAAs were saccular (87.9%) and multilobulated (91.7%). Calcified aortic plaque was present in 93.2% and within the aneurysm in 51.5%. INAA instability was classified as contained rupture (27.3%), impending rupture (26.5%), and free rupture (3.8%). Rapid expansion was demonstrated in 13 of 14 (92.9%) aneurysms with sequential CT studies. Periaortic inflammation was demonstrated as periaortic enhancement (94.7%), fat stranding (93.9%), soft-tissue mass (92.4%), and lymphadenopathy (62.1%). Surrounding involvement included psoas muscle (17.8%), spondylitis (11.4%), and perinephric region (2.8%). Twelve patients demonstrated thoracic and abdominal INAA complications: fistulas to the esophagus (20%), bronchus (16%), bowel (1.9%), and inferior vena cava (IVC) (0.9%). CONCLUSION: The most common CT features of INAA were saccular aneurysm, multilobulation, and calcified plaques. The most frequent periaortic findings were enhancement, fat stranding, and soft-tissue mass. Surrounding involvement, including psoas muscle, IVC, gastrointestinal tract, and bronchi, was infrequent but may develop as critical INAA complications.

Infected Aortic Aneurysm Caused by Streptococcus zooepidemicus: A Case Report and Literature Review.

A 66-year-old Japanese male working at a stable developed abdominal pain and fever and was brought to the emergency department. The computed tomography scan revealed an aneurysm of approximately 70 mm in diameter, with an irregular border, at the infrarenal abdominal aorta. Emergency surgery was performed with a bifurcated Dacron graft. Streptococcus zooepidemicus was observed on the aneurysm wall. He was discharged in good condition and was prescribed oral amoxicillin/clavulanic acid for 4 months. He has remained well and did not develop inflammation. Evaluation of patient history and data, including the consumption of unpasteurized dairy food, occupation, and direct contact with animals, is important for an early diagnosis, a prompt surgery, and an appropriate antibiotic therapy.

Atraumatic splenic rupture and infection-related glomerulonephritis in a patient with infected aortic aneurysm: A case report.

INTRODUCTION: Atraumatic splenic rupture is very rare and the case is often difficult to determine. We report a case of atraumatic splenic rupture in a patient with an infected aortic aneurysm. CASE PRESENTATION: A 40-year-old man under evaluation and treatment for renal dysfunction presented with the sudden onset of epigastric pain. The patient had a previous history of aortic arch replacement for Stanford type B aortic dissection. Contrast-enhanced computed tomography revealed intraabdominal hemorrhaging around the spleen and intrasplenic extravasation of contrast medium, and atraumatic splenic rupture was diagnosed. The patient slipped into hemorrhagic shock, and emergency splenectomy was scheduled. The histopathological diagnosis was splenic rupture with splenic infarction. The patient became febrile on postoperative day 10. Repeat contrast-enhanced computed tomography revealed enlargement of a cystic aortic aneurysm that was present prior to splenectomy. Infected aortic aneurysm was suspected, which was confirmed following thoracic endovascular aortic repair performed on postoperative day 12. DISCUSSION: We consider that splenic rupture occurred following infected of the kidney and spleen by an infected aortic aneurysm. CONCLUSION: Infection should be considered as a cause in patients with atraumatic splenic rupture.

Emphysematous aortic arch aneurysm infected with Salmonella: A case report.

Infected aortic aneurysm is a relatively rare disease that is extremely difficult to manage, resulting in a poor prognosis. We rescued a patient with Salmonella-infected aortic arch aneurysm surrounded with a specific and massive emphysema, despite experiencing aortic rupture, including delayed esophageal perforation after surgery.

Open surgery and endovascular repair for mycotic aortic aneurysms: Benefits beyond survival.

OBJECTIVE: Endovascular techniques have been increasingly used to treat mycotic aortic aneurysms. However, apart from survival, the potential benefits of open surgery and endovascular repair for mycotic aortic aneurysms are poorly understood. The aim of this study was to evaluate the short- and mid-term outcomes after open surgery versus endovascular repair for mycotic aortic aneurysms. METHODS: All patients treated for mycotic aortic aneurysms at Peking University People's Hospital between 2001 and 2017 were identified. Survival was analyzed using Kaplan-Meier analysis and log-rank tests. The reoperation rate was analyzed using a competing-risk analysis. RESULTS: Forty-three patients were identified. The mean follow-up time was 41 months (median, 29; range, 1-135 months). The 30-day mortality in the open surgery group was 8.7% (2/23) versus 5% (1/20) in the endovascular repair group (P = .999). The overall survival for open surgery and endovascular repair was 78% versus 75%, respectively, at 1 year, and 69% versus 41% (P = .210), respectively, at 5 years. But during the follow-up, the open surgery group demonstrated multiple benefits, including a shorter length of hospital stay (26.80 ± 14.1 days vs 42.73 ± 21.22 days, P = .026), fewer readmissions (mean 0.61 vs 1.30, P = .037), and lower infection-related reoperations (P = .018) than endovascular repair at 3 years. Subgroup analysis revealed better survival for open surgery in patients with a periaortic mass less than 20 mm (P = .03). CONCLUSIONS: There were no significant differences between endovascular repair and open surgery in survival. However, in the mid-term, the potential benefits of open surgery are favorable compared with endovascular repair, including lower infection-related reoperation rates and reduced medical burden.

Presence of periaortic gas in Clostridium septicum-infected aortic aneurysm aids in early diagnosis: a case report and systematic review of the literature.

BACKGROUND: Clostridium septicum-infected aortic aneurysm is a fatal and rare disease. We present a fatal case of C. septicum-infected aortic aneurysm and a pertinent literature review with treatment suggestions for reducing mortality rates. CASE PRESENTATION: A 58-year-old Japanese man with an unremarkable medical history presented with a 3-day history of mild weakness in both legs, and experienced paraplegia and paresthesia a day before admission. Upon recognition of signs of an abdominal aortic aneurysm and paraplegia, we suspected an occluded Adamkiewicz artery and performed a contrast-enhanced computed tomography scan, which revealed an aortic aneurysm with periaortic gas extending from his chest to his abdomen and both kidneys. Antibiotics were initiated followed by emergency surgery for source control of the infection. However, owing to his poor condition and septic shock, aortic repair was not possible. We performed bilateral nephrectomy as a possible source control, after which we initiated mechanical ventilation, continuous hemodialysis, and hemoperfusion. A culture of the samples taken from the infected region and four consecutive blood cultures yielded C. septicum. His condition gradually improved postoperatively; however, on postoperative day 10, massive hemorrhage due to aortic rupture resulted in his death. CONCLUSIONS: In this patient, C. septicum was thought to have entered his blood through a gastrointestinal tumor, infected the aorta, and spread to his kidneys. However, we were uncertain whether there was an associated malignancy. A literature review of C. septicum-related aneurysms revealed the following: 6-month mortality, 79.5%; periaortic gas present in 92.6% of cases; no standard operative procedure and no guidelines for antimicrobial administration established; and C. septicum was associated with cancer in 82.5% of cases. Thus, we advocate for early diagnosis via the identification of periaortic gas, as an aortic aneurysm progresses rapidly. To reduce the risk of reinfection as well as infection of other sites, there is the need for concurrent surgical management of the aneurysm and any associated malignancy. We recommend debridement of the infectious focus and in situ vascular graft with omental coverage. Postoperatively, orally administered antibiotics must be continued indefinitely (chronic suppression therapy). We believe that these treatments will decrease mortality due to C. septicum-infected aortic aneurysms.

Rapidly Expanding Infectious Aortic Aneurysm Caused by Perforated Colon Cancer.

A 50-year-old male smoker presented with a perforated colon cancer and underwent an extended right colectomy. Feculent peritonitis was treated with empiric antibiotics. Postoperatively he developed severe back pain and rising leukocytosis. Serial computed tomography revealed a rapidly expanding infrarenal aortic aneurysm. He was urgently treated with extra-anatomic bypasses and aortic resection. No organisms grew from the resected aortic wall. He was discharged in stable condition, and the ileostomy was reversed 9 months later.

Increased serum IgG4 levels and intimal IgG4-positive cell infiltration in rapidly growing aortic aneurysm.

A 67-year-old Japanese man had been complaining of discomfort in the chest and back and feeling febrile for 2 weeks. Chest computed tomography indicated a thoracic aortic aneurysm. He occasionally showed a high fever (up to 38.0°C), even after hospital admission, irrespective of antibiotic therapy. The patient was found to have elevated serum IgG4 levels (366 mg/dL). The aneurysm demonstrated rapid growth; therefore, rifampicin-soaked woven Dacron synthetic graft replacement was performed 22 days after admission. Immunohistostatining of the resected aorta segment showed an IgG4-positive plasma cell infiltrate within the intimal layer neighboring the cholesterol-rich atheromatous plaque. After surgery, the patient's serum IgG4 level dropped acutely; however, it did not reach the normal range. The possible role of IgG4 in the development or suppression of aortic remodeling, as well as in atherogenesis, among patients with rapidly growing aortic aneurysm requires further investigation.