Infected infrarenal aortic aneurysms: When is in situ reconstruction safe?

Mycotic aortic aneurysm in a debilitated patient with compromised immunity; beware of Candida!

Candida is a rare cause of infected aortic aneurysms. We report the case of a diabetic patient with end stage kidney disease who underwent repair of a leaking abdominal aortic aneurysm. He was on long-term antibiotic treatment for malignant otitis externa. Candida albicans was isolated from the culture of the excised aneurysm wall. An infected aortic aneurysm due to Candida has not been previously reported in a patient with malignant otitis externa. This case report aims to highlight that Candida should be suspected as a cause of infected aortic aneurysms in patients with debilitation and chronic immunosuppression. Management of such cases can be extremely challenging, especially in resource-poor settings, and we will be touching upon the advantages and disadvantages of various treatment options.

Mycotic/Infective Native Aortic Aneurysms: Results After Preferential Use of Open Surgery and Arterial Allografts

OBJECTIVE

Mycotic/infective native aortic aneurysms (INAA) are managed heterogeneously. In the context of disparate literature, this study aimed to assess the outcomes of INAA surgical management and provide comprehensive data in alignment with recent suggestions for reporting standards.

METHODS

A retrospective review of patients presenting with INAA from September 2002 to March 2020 at two institutions was conducted. In hospital mortality, 90 day mortality, overall mortality, and infection related complications (IRCs) were the study endpoints. Overall survival and IRC free survival were estimated, and predictors of mortality tested using uni- and multivariable analyses.

RESULTS

Seventy patients (60 men [86%], median age 68 years [range 59 - 76 years]) were included. Twenty (29%) were ruptured at presentation. INAA location was thoracic in 11 (16%) cases, thoraco-abdominal in seven (10%), and abdominal in 50 (71%). Half of the abdominal INAAs were suprarenal. Two INAAs were concomitantly abdominal and thoracic. Pathogens were identified in 83%. The bacterial spectrum was scattered, with rare Salmonella species (n = 6; 9%). Open surgical repair was performed in 66 (94%) patients, including five conversions of initially attempted endovascular grafts (EVAR), three hybrid procedures, and one palliative EVAR. Vascular substitutes were cryopreserved arterial allografts (n = 67; 96%), prosthesis (n = 2), or femoral veins (n = 1). Kaplan-Meier estimates of overall survival at 30 and 90 days were 87% (95% confidence interval [CI] 76.6 - 93.0) and 71.7% (95% CI 59.2 - 80.9), respectively. The overall in hospital mortality rate was 27.9% (95% CI 1.8 - 66.5). IRCs occurred in seven (10%) patients. The median follow up period was 26.5 months (range 13.0-66.0 months). Chronic kidney disease (CKD) was independently related to in hospital mortality (odds ratio [OR] 20.7, 95% CI 1.8 - 232.7). American Society of Anesthesiologists score of 3 (OR 6.0, 95% CI 1.1 - 33.9), 4 (OR 14.9, 95% CI 1.7 - 129.3), and CKD (OR 32.0, 95% CI 1.2 - 821.5) were related to 90 day mortality.

CONCLUSION

Surgical INAA management has significant mortality and a low re-infection rate. EVAR necessitated secondary open repair, but its limited use in this report did not allow conclusions to be drawn.

Rupture of a dissecting thoracoabdominal aortic aneurysm due to Citrobacter freundii infection

We describe a case of an elderly man with Citrobacter freundii-associated infectious rupture of a dissecting thoracoabdominal aortic aneurysm. We performed an emergency thoracoabdominal aortic replacement using a rifampicin-soaked prosthetic graft and omental flap wrapping. The patient was discharged on postoperative day 255, although he experienced pseudomembranous enteritis and paraplegia.

Native and prosthetic graft infections of the thoracic aorta: surgical management

 

OBJECTIVES

Infection of the native aorta or after previous open or endovascular repair of the thoracic aorta is associated with high risks for morbidity and mortality. We analysed the outcome after surgical management of a native mycotic aneurysm or of prosthetic graft infection of the descending aorta.

METHODS

From June 2000 to May 2019, a total of 39 patients underwent surgery in our centre for infection of the native descending aorta (n = 19 [49%], group A) or a prosthetic descending aorta [n = 20 (51%), group B]. In the 20 patients in group B, a total of 8 patients had prior open aortic repair with a prosthesis and 12 patients had a previous endovascular graft repair.

RESULTS

The cohort patients had a mean age of 57 ± 14; 62% were men (n = 24). The most common symptoms at the time of presentation included fever, thoracic or abdominal pain and active bleeding. Emergency surgery was performed in 11 patients (28%); 3 patients had emergency endovascular stent grafts implanted during thoracic endovascular aortic repair for aortic rupture before further open repair. The 30-day mortality was 42% in group A and 35% in group B. The 90-day mortality was 47% in group A and 45% in group B. Pathogens could be identified in approximately half of the patients (46%). The most commonly identified pathogens were Staphylococcus aureus in 6 patients (15%) and Staphylococcus epidermidis in 4 patients (10%). Survival of the entire group (including patients with both native and prosthetic graft infections) was 44 ± 8%, 39 ± 8% and 39 ± 8% at 1, 2 and 3 years after surgery. The percentage of patients who survived the initial perioperative period was 81 ± 9%, 71 ± 9% and 71 ± 10% at 1, 2 and 3 years after surgery.

CONCLUSIONS

Patients with infection of the descending aorta, either native or prosthetic, are associated with both high morbidity and mortality. However, patients who survive the initial perioperative period have an acceptable long-term prognosis. In emergency situations, thoracic endovascular aortic repair may help to stabilize patients and serve as bridge to open repair.

Mycotic Abdominal Aortic Aneurysms - A Tertiary Centre Experience and Formulation of a Management Protocol

BACKGROUND

Mycotic abdominal aorta aneurysm (MAAA) is a rare and life-threatening condition. Because of its rarity, there is a lack of adequately powered studies and consensus on its treatment and follow up. This study aimed to review the outcomes following surgical intervention for MAAA in a single tertiary centre and to formulate a management protocol based on available evidence and expert opinion.

MATERIALS AND METHODS

Data were collected by retrospective review of case records of all patients who underwent repair of MAAA in a single tertiary referral centre from 2001 to 2018. Demographic, clinical and outcome data were analysed and compared with previously published series in the literature. A management protocol was formulated based on available literature which was then reviewed and modified as per expert opinion from multidisciplinary discussions.

RESULTS

Seventeen patients underwent repair of MAAA during the study period including 4 Open repairs, 4 surgeon modified fenestrated endovascular aortic aneurysm repairs (SM FEVAR) and 9 endovascular aortic aneurysm repairs (EVAR). One-year overall survival was 94.1%, 3-year survival was 81.8% and 5-year survival was 75.0%. The infection-free survival at 1, 3, and 5 years was 87.5%, 81.8% and 62.5%, respectively. The overall survival and infection-free survival curves for Open repair, EVAR and SM FEVAR when compared using Log Rank (Mantel-Cox) test and did not show any statistically significant difference.

CONCLUSIONS

Management of MAAA with selective use of open or endovascular repair, in combination with appropriate long-term antibiotic therapy, can achieve acceptable outcomes. The proposed protocol can aid as a guiding document for the management of MAAA but needs taking into consideration individual patient variability and local expertise.

Ruptured pseudoaneurysm of the thoracic aorta mimicking lung cancer: A case report

A 70‐year‐old woman was admitted to a local hospital with a five‐day history of back pain. She had been referred to our hospital after an abnormal chest shadow was identified on chest X‐ray. Chest computed tomography (CT) revealed an anterior mediastinal mass in the upper lobe of the left lung. Her general condition was good. She was diagnosed with lung cancer, and examination was planned. However, respiratory failure rapidly worsened on hospital day 2, and a ruptured pseudoaneurysm of the thoracic aorta (PTA) was diagnosed from contrast‐enhanced CT. Emergency thoracic endovascular aortic repair was successfully performed, and her postoperative course was uneventful. The hemodynamics of the PTA were stable in the case of this patient, but the risk of rupture is extremely high and frequently fatal. PTA should therefore be included among the differential diagnoses of mediastinal tumor.

Key points

Significant findings of the study

Pseudoaneurysm of the thoracic aorta (PTA) may present on imaging findings that resemble lung cancer.

What this study adds

PTA should be included among the differential diagnoses of mediastinal tumor. Clinicians therefore need to be familiar with the imaging findings of PTA.

Multidisciplinary Management of an Aorto-esophageal Injury Caused by Foreign Body Ingestion

A 37-year-old incarcerated male ingested a complex "X-shaped" foreign body that resulted in a penetrating aorto-esophageal injury. A primary esophagotomy with retrieval of the foreign body and muscle flap closure was performed simultaneously with thoracic endovascular aortic repair. This multidisciplinary surgical approach controls for both immediate exsanguination and postoperative complications to improve patient outcome.

Therapeutic Strategies for Infectious Multiple Aortic Aneurysms: Thoracoabdominal Aortic Aneurysm Treatment Using a Fenestrated Stent-Graft

Recently, it has been reported that a fenestrated stent graft is an effective option in the treatment of pararenal artery abdominal aortic aneurysm. We report the case of a 72-year-old male patient with multiple aortic aneurysms in the distal arch, thoracoabdominal aorta, right common iliac artery, as well as a pararenal abdominal aortic aneurysm. The patient was found to have a mass with a tendency of rapid expansion within a month from its discovery. Because it was a saccular aneurysm with a tendency of rapid expansion and wide spread, the risk of rupture was judged to be high, and surgical treatment became necessary. One-stage treatment was desirable; therefore, endovascular treatment with a fenestrated stent graft was selected. Four fenestrations were made to a stent graft for the celiac artery, superior mesenteric artery, and bilateral renal arteries. The postoperative computed tomography (CT) showed no branch occlusion or endoleak, and the 2-year postoperative CT showed the shrinkage and subsequent disappearance of the aortic aneurysm at the treatment site. For extensive aortic aneurysm, including pararenal artery abdominal aortic aneurysms, one-stage treatment with fenestrated stent graft was considered to be effective as a treatment strategy. (This is a translation of Jpn J Vasc Surg 2020; 29: 9–13.)

On the Diagnosis of Mycotic Aortic Aneurysms

Objective:

There is striking paucity in consensus on the terminology, definition, and diagnostic criteria of mycotic aortic aneurysms. This literature study aims to elucidate this scientific omission, discuss its consequences, and present a proposition for reporting items on this disease.

Methods:

A systematic literature review on PubMed and Medline using mycotic and infected aortic aneurysms between 1850 and 2017 was performed. Articles were assessed according to a protocol regarding terminology, definition, and diagnostic criteria. Case series with less than 5 patients were excluded.

Results:

A total of 49 articles were included. The most prevalent term was mycotic aortic aneurysm but there was no widely accepted definition. Most modern publications used a diagnostic workup based on a combination on clinical presentation, laboratory results, imaging findings, and intraoperative findings. How these protean variables should be balanced was unclear. A proposition of reporting items was framed and consisted of definition of disease used, basis of diagnostic workup, exclusion criteria, patient characteristics, laboratory and imaging findings, aneurysm anatomy, details on treatment, pre/postoperative antibiotic treatment, and details on follow-up.

Conclusions:

This article emphasizes the need to standardize definition, terminology, and diagnostic criteria for mycotic aortic aneurysms and proposes reporting items enhancing comparability between studies.

An Uncommon Cause of Deep Vein Thrombosis: Mycotic Aneurysm Secondary to Salmonella Arteritis

Mycotic aneurysm is an uncommon surgical emergency with high mortality. Endovascular infection due to salmonella is the commonest cause of intra-abdominal mycotic aneurysm. We report a rare presentation of mycotic aneurysm in a 78-year-old man who presented to the accident and emergency department with deep vein thrombosis due to compression of the iliac vein by a mycotic aneurysm arising from the internal iliac artery and an adjacent abscess. A comprehensive review of the aetiology, clinical presentation and management of mycotic aneurysm secondary to salmonella arteritis is presented.

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.

Infrarenal Infected Aortic Aneurysm Caused by Streptococcus pyogenes

Infectious aneurysm is a rare entity associated with significant morbidity and mortality. Current knowledge on pathogenesis, outcome, diagnosis, management, and follow-up remains debatable. We report the case of a patient with Streptococcus pyogenes aneurysm who was successfully treated with a homograft implant and discuss microbiological characteristics, diagnostic methods, and treatment options currently available for this serious disease.

Infections of the Aorta: Case Report and Review of Treatment

Radiographic documentation of the rapid development of an aortic infection has not previously been reported. We report the case of a 68-year-old woman who presented with back pain. A computed tomographic(CT) scan documented a nondisplaced L1 compression fracture as well as an atherosclerotic but nonaneurysmal aorta. Two weeks after discharge, she developed left lower lobe pneumonia and was readmitted. A second CT scan was obtained because of continuous complaints of back pain. A contained rupture of the visceral aorta was now clearly visible. Emergent operation successfully repaired her aorta.

The microorganisms responsible for aortic infection have changed since the widespread use of antibiotics. Patterns of aortic involvement have also evolved. The difficulty in making these diagnoses, the role of current antibiotic therapy, and the surgical options for these infections will be discussed.

An Infected Abdominal Aortic Aneurysm Caused by Helicobacter cinaedi

We present a rare case of an infected abdominal aortic aneurysm due to Helicobacter cinaedi that was detected by blood culture. A 79-year-old man with lumbago and left lower quadrant pain was admitted for the treatment of an infected abdominal aortic aneurysm. H. cinaedi was isolated from a blood culture, which was obtained on admission. The aneurysm was successfully treated with antibiotic therapy, aneurysmectomy, debridement, replacement of a bifurcated Dacron prosthesis, and omental wrapping. Our present case suggests that H. cinaedi should be considered as the causative agent of an infected aortic aneurysm.

Mycotic abdominal aortic aneurysm caused by Campylobacter fetus: a case report and literature review

Campylobacter spp. usually cause gastrointestinal infections, but among them, Campylobacter fetus is a well-known organism causing mycotic abdominal aortic aneurysm (MAAA), which requires proper surgical intervention and antibiotic therapy. We report a 65-year-old man who was successfully treated by an in situ operation using a rifampicin (RFP)-bonded J-Graft for C. fetus-induced MAAA. We performed a review of the English literature on MAAA caused by C. fetus and summarized the results of the cases (28 cases). All but 2 of the patients (92.9%) were men. Blood culture and arterial wall culture were positive in 63% and 73.1% of the cases, respectively. Aneurysm rupture was seen in half of the patients, and approximately half of those patients died. Among the 18 patients who underwent in situ graft replacement, only 1 patient (5.6%) died after surgery. Antibiotic therapy was performed for more than 1 month in most cases, and overall mortality rate was 25.9% (7 of 27 cases, 3 deaths before the operation and 4 deaths after surgery). Although extra-anatomic bypass has been conventionally performed after complete resection of an MAAA, the utility of in situ surgery has generally been recognized. Our review suggests that the in situ operation can be a choice also in cases of C. fetus-associated MAAA. Furthermore, our case suggested the clinical utility of a newly manufactured prosthetic graft, J-Graft, for such surgical treatment.

Clinical, microbiologic, and outcome analysis of mycotic aortic aneurysm: the role of endovascular repair

BACKGROUND

Mycotic aortic aneurysm (MAA) is an infrequent but devastating form of vascular disease.

METHODS

We conducted a retrospective cohort study at a major medical center to identify independent risk factors for MAA and to provide opinions about treating it. The study population consisted of 43 patients who had had 44 MAAs over a period of 15 y.

RESULTS

All of the patients had positive blood cultures, radiologic findings typical of MAA, and clinical signs of infection (leukocytosis, fever, and elevated C-reactive protein). The mean age of the patients was 63.8±10.6 y and the mean period of their follow up was 35.7±39.3 mo. Twenty-nine patients with MAAs underwent traditional open surgery, 11 others received endovascular stent grafts, and four MAAs were managed conservatively. The most frequent causative pathogens were Salmonella (36/44 patients [81.8%]), in whom organisms of Salmonella serogroup C (consisting mainly of S. choleraesuis) were identified in 14 patients, organisms of Salmonella serogroup D were identified in 13 patients, and species without serogroup information were identified in nine patients. The overall mortality in the study population was 43.2% (with an aneurysm-related mortality of 18.2%, surgically related mortality of 13.6%, and in-hospital mortality of 22.7%).

CONCLUSIONS

Shock is a risk factor for operative mortality. Misdiagnosis and treatment of MAA as low back pain, co-existing connective-tissue disease such as systemic lupus erythematosus and rheumatoid arthritis, and Salmonella serogroup C-associated bacteremia are risk factors for aneurysm-related death. Endovascular repair should be considered as an alternative option to the open repair of MAA.

Fluorine-18-fluorodeoxyglucose positron emission tomography-computed tomography for diagnosis of infected aortic aneurysms

BACKGROUND

Infected aortic aneurysms are diagnosed on the basis of a positive bacterial blood culture, clinical evidence of inflammation, and morphologic findings on computed tomography (CT). However, preoperative diagnosis is often difficult because blood cultures are frequently negative and patients can be asymptomatic. Because therapeutic approaches differ significantly, it is vital to determine whether an aortic aneurysm is infected prior to surgery.

METHODS

From June 2007 to July 2012, we investigated 11 cases of suspected infected aortic aneurysm using fluorine-18-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG-PET/CT). In addition to contrast-enhanced CT examination, blood culture and histologic examinations were performed to aid diagnosis.

RESULTS

Patients with a final diagnosis of infected aortic aneurysms showed a maximum standard uptake value (SUVmax) of >4.46, whereas infection-free cases had an SUVmax of <2.59 (mean 6.5 ± 1.8 vs. 1.9 ± 0.5; P < 0.001).

CONCLUSION

FDG-PET/CT examination is useful in the diagnosis of infected aortic aneurysms.

Thoracic endovascular aortic repair in management of aortoesophageal fistulas

OBJECTIVE

To provide a systematic review of the outcomes of thoracic endovascular aortic repair (TEVAR) for aortoesophageal fistula (AEF) and to identify prognostic factors associated with poor outcomes.

METHODS

Literature searches of the Embase, Medline, and Cochrane databases identified relevant articles reporting results of TEVAR for AEF. The main outcome measure was the composite of aortic mortality, recurrence of the AEF, and stent graft explantation. The secondary outcome measure was aortic-related mortality.

RESULTS

Fifty-five articles were integrated after a literature search identified 72 patients treated by TEVAR for AEFs. The technical success rate of TEVAR was 87.3%. The overall 30-day mortality was 19.4%. Prolonged antibiotics (>4 weeks) were administered in 80% of patients. Concomitant or staged resection or repair of the esophagus was performed in 44.4% of patients. Stent graft explantation was performed within the first month after TEVAR as a planned treatment in 11.1%. After a mean follow-up of 7.4 months (range, 1-33 months), the all-cause mortality was 40.2%, and the aortic-related mortality was 33.3. Prolonged antibiotic treatment (P = .001) and repair of AEFs due to a foreign body (P = .038) were associated with a significant lower aortic mortality. On univariate analysis, TEVAR and concomitant or staged adjunctive procedures (resection, repair of the esophagus, or a planned stent graft explantation) were associated with a significantly lower incidence of aortic-related mortality (P = .0121). When entered into a binary logistic regression analysis, prolonged antibiotic treatment was the only factor associated with a significant lower incidence of the endpoint (P = .003).

CONCLUSIONS

Late infection or recurrence of the AEF and associated mortality rates are high when TEVAR is used as a sole therapeutic strategy. Prolonged antibiotic treatment has a strong negative association with mortality. A strategy of a temporizing endovascular procedure to stabilize the patient in extremis, and upon recovery, an open surgical esophageal repair with or without stent graft explantation is advocated.

Treatment of infected abdominal aortic aneurysm caused by Salmonella

BACKGROUND

We reviewed the outcomes of patients treated for nontyphoidal Salmonella-infected abdominal aortic aneurysm (AAA) treatment at a single center.

METHODS

This was a retrospective chart review of 26 patients with nontyphoidal Salmonella-infected AAA. Four patients underwent medical therapy alone, while 22 patients underwent surgical therapy. Revascularization method selection was dependent on preoperative antibiotic response in the surgical therapy group.

RESULTS

The in-hospital mortality rate for the surgical therapy group was 14%, while the rate for the medical therapy group was 100%. Overall survival for the surgical therapy group was 82%, while the reinfection rate was 9%. In the surgical therapy group, 2 patients had periaortic abscesses and underwent in situ prosthetic graft replacement; none developed graft-related complications or died in the hospital. Kaplan-Meier analysis and log-rank testing revealed no significant differences in graft-related complication and overall survival rates between in situ prosthetic graft group and extra-anatomic bypass group. Salmonella choleraesuis had a higher antimicrobial resistance rate than other isolates. The predictors of survival were clinical presentation of abdominal pain and receiving surgical therapy.

CONCLUSIONS

If patients with Salmonella-infected AAAs have good responses to preoperative antibiotic therapy, in situ prosthetic graft replacement is a viable revascularization method, even in the situation of periaortic abscess presentation formation.

In situ polytetrafluoroethylene graft bypass for primary infected aneurysm of the infrarenal abdominal aorta

BACKGROUND

Reinfection is a major issue of surgical treatment for patients with infected abdominal aortic aneurysm (AAA). The present report describes outcomes after use of our procedure for treating patients with infected aneurysm of the infrarenal abdominal aorta. The procedure involved an in situ polytetrafluoroethylene (PTFE) graft bypass and omental wrapping of the graft. The procedure was used regardless of the presence of Gram-stain-positive pus or tissue or the type of pathogen identified.

METHODS

We retrospectively reviewed nine consecutive patients with primary infected aneurysms of the infrarenal abdominal aorta treated from June 2001 to August 2006 at the Asan Medical Center, Seoul, Korea. Diagnosis was based on preoperative abdominopelvic CT scans. Treatment involved removal of all infected tissue, including infected aorta tissue, in situ PTFE graft reconstruction, and wrapping of the graft with retrocolically transposed great omentum. Sensitive antibiotics were administered before and after the operation.

RESULTS

In all cases, aneurysms were the result of aortitis and aortic wall perforation, and presented as aortic pseudoaneurysms with rupture. The pathogens identified were Salmonella non-typhi (n = 4), Klebsiella pneumoniae (n = 2), Streptococcus pneumoniae (n = 1), Citrobacter freundii (n = 1), and Brucella abortus (n = 1). There was no infection-related morbidity or mortality during a median follow-up period of 49 months.

CONCLUSIONS

Surgical treatment comprising complete removal of all infected tissue, in situ PTFE graft reconstruction, and omental wrapping of the graft was effective in treating infected AAA. Key adjunct procedures were a precise preoperative diagnosis using abdominopelvic CT scans, and pre- and postoperative sensitive antibiotic treatment.

New bacteriological patterns in primary infected aorto-iliac aneurysms: a single-centre experience

OBJECTIVES

To assess causative pathogens and surgical outcomes in patients with primary infected aorto-iliac aneurysms at our institution.

DESIGN

Retrospective study of patients treated at a university hospital between 1992 and 2009.

RESULTS

We identified 26 patients (median age, 63 years) with primary infected aneurysms on the aorta (descending thoracic, n = 2; thoraco-abdominal, n = 3; suprarenal, n = 2; infrarenal, n = 15) or iliac arteries (n = 4). Among them, 22 were symptomatic, including 13 with ruptured aneurysms. The causative organisms, identified in 25/26 patients, were Campylobacter fetus, n = 6; Streptococcus pneumoniae, n = 4; Listeria, n = 3; Salmonella, n = 2; Mycobacterium tuberculosis, n = 2; Staphylococcus aureus, n = 1; and other, n = 7. Immune suppression was a feature in 10 (38.4%) patients. Revascularisation was performed in situ in 23 patients (10 allografts, eight grafts, three superficial femoral veins, and 2 stentgrafts) and by extra-anatomic bypass in three patients. Hospital mortality was 23% (in situ group, 17.4%; extra-anatomic group, 66.7%; χ(2)(Yates), P = 0.24). During follow-up in the 20 survivors (median, 48.5 months), there were two non-infection-related deaths (five and 24 months) and six (30%) vascular complications.

CONCLUSIONS

The bacteriological spectrum of primary infected aorto-iliac aneurysms was wider than previously reported. The availability of new diagnostic tests and increased prevalence of immunosuppression may explain this finding.

Abdominal aortic pseudoaneurysm secondary to melioidosis

Melioidosis is an infective condition which is common in South East Asia. It can present in various forms like cutaneous abscess, pneumonia and severe septicaemia. However, melioidosis causing abdominal aortic pseudoaneurysms is extremely rare and a difficult condition to diagnose and treat. We present our management of two cases of abdominal aortic pseudoaneurysms secondary to melioidosis and their subsequent outcomes.

Infected (mycotic) aneurysms: spectrum of imaging appearances and management

Infected aneurysms are uncommon. The aorta, peripheral arteries, cerebral arteries, and visceral arteries are involved in descending order of frequency. Staphylococcus and Streptococcus species are the most common causative pathogens. Early clinical diagnosis of infected aneurysms is challenging owing to their protean manifestations. Clinically apparent infected aneurysms are often at an advanced stage of development or are associated with complications, such as rupture. Nontreatment or delayed treatment of infected aneurysms often has a poor outcome, with high morbidity and mortality from fulminant sepsis or hemorrhage. Current state-of-the-art imaging modalities, such as multidetector computed tomography and magnetic resonance imaging, have replaced conventional angiography as minimally invasive techniques for detection of infected aneurysms in clinically suspected cases, as well as characterization of infected aneurysms and vascular mapping for treatment planning in confirmed cases. Doppler ultrasonography allows noninvasive assessment for infected aneurysms in the peripheral arteries. Imaging features of infected aneurysms include a lobulated vascular mass, an indistinct irregular arterial wall, perianeurysmal edema, and a perianeurysmal soft-tissue mass. Perianeurysmal gas, aneurysmal thrombosis, aneurysmal wall calcification, and disrupted arterial calcification at the site of the infected aneurysm are uncommon findings. Imaging-guided endovascular stent-graft repair and embolotherapy can be performed in select cases instead of open surgery. Familiarity with the imaging appearances of infected aneurysms should alert the radiologist to the diagnosis and permit timely treatment, which may include endovascular techniques.

Aortitis and Bacterial Endocarditis

Aortitis is an inflammatory condition that can be due to numerous causes. It is a diagnostic quandary because it commonly shows similar clinical, pathologic, and aortographic features independently of the etiology. A case of aortitis, possibly secondary to bacterial endocarditis, initially misdiagnosed as an atherosclerotic aortic ulcer and managed with an endoprosthesis is presented. On the fourth postoperative day, the patient presented with fever and worsening abdominal pain, which was later diagnosed as infectious aortitis. It required débridement and replacement of the infrarenal aorta with a cadaveric cryopreserved allograft. This case emphasizes the need for early diagnosis and aggressive therapy to avoid life-threatening sequelae.

Primary Aortoappendicular Fistula Arising from an Infected, Chronic, Contained, Ruptured Abdominal Aortic Aneurysm

Gastrointestinal bleeding can be caused by a variety of pathologies. Primary aortoappendicular fistula is rare and, in our case, arose in addition to a chronic contained rupture sac of an abdominal aortic aneurysm. Clinical diagnosis is difficult. Aortic aneurysmorrhaphy along with extensive debridement and emphasis on antibiotic therapy is curative.

Arterial infections in the new millenium: an old problem revisited

The natural history of infected aneurysms or arterial infections is characterized by rapid expansion leading to rupture, pseudoaneurysm formation, and sepsis. Treatment options include in situ grafting either with prosthetic or autogenous grafts or with cryopreserved allografts (CPAs), resection of the aneurysm with remote bypass grafting, and ligation. The purpose of this study was to review our recent experience with these infections and to present long-term follow-up with in situ CPAs. From January 2000 through June 2005, we treated nine patients with infected aneurysms and one patient with an infection without aneurysm formation. The infection involved the infrarenal abdominal aorta in six patients and the femoral artery in three patients. One patient had an infected splenic artery aneurysm. Aortic rupture occurred in five of the six patients with infected aortas. Two of the three patients with infected femoral aneurysms presented with recurrent hemorrhage. Of the six patients with aortic infections, five were treated with in situ CPAs. One patient was treated with aortic resection and axillofemoral grafting. Two patients with femoral aneurysms were treated with in situ CPAs, and the third patient underwent aneurysm resection and prosthetic grafting through the obturator foramen. The patient with the splenic aneurysm underwent combined valve replacement, aneurysm resection, and splenectomy. Three of the six patients with aortic infections died postoperatively, all of whom were septic at presentation. The cause of death in these three patients was multiple organ failure in two and overwhelming sepsis in one. The three survivors are alive and well with up to 5-year follow-up. The three patients with infected femoral aneurysms are alive and well with follow-up extending to 44 months. The patient with the splenic aneurysm is doing well. No recurrent infections have been noted among the survivors. The CPAs have remained structurally intact in all. The mortality rate among patients with abdominal aortic infections remains high and is likely related to their preoperative septic state. In situ grafting with CPAs appears to be a reasonable treatment option for arterial infections. CPAs appear to maintain their structural integrity and to be resistant to recurrent infection.