Analysis of antibiotic strategies to prevent vascular graft or endograft infection after surgical treatment for infective native aortic aneurysms: a systematic review.

INTRODUCTION: Some patients with an infective native aortic aneurysm (INAA) develop an aortic vascular graft or endograft infection (VGEI) even after successful open surgical repair or endovascular intervention. The aim of the systematic review and meta-analysis performed herein was to compare the clinical outcomes of different surgical and antibiotic treatment strategies. METHODS: We systematically searched PubMed, MEDLINE, EMBASE and Web of Science. The keywords used for the search were "mycotic aortic aneurysm", "infected aortic aneurysm", "infective native aortic aneurysm", "antibiotics", "surgery", and "endovascular". The search was limited to articles written in English and to studies involving humans. Articles published before 2000 were excluded. Case reports and review articles were excluded. RESULTS: Of the 524 studies retrieved from our search of the databases, 47 articles were included in this study. Among the 47 articles (1546 patients, 72.8% of whom were male) retrieved, five articles were excluded from the subgroup analysis because the data concerning open surgical repair and endovascular intervention could not be separated. The remaining 42 articles included a total of 1179 patients who underwent open surgical repair (622 patients) or endovascular intervention (557 patients) for INAA. There was a statistically significant difference (p = 0.001) in the pooled in-hospital mortality rate between the open surgical repair group (13.2%, 82/622) and the endovascular intervention group (7.2%, 40/557). However, there was a statistically significant difference (p < 0.001) in the aortic VGEI rate between the open surgical repair group (5.4%). 29/540) and endovascular intervention (13.3%, 69/517) group. For patients who underwent open surgical repair, a lower rate of aortic vascular graft infection was associated with long-term antibiotic use (p = 0.005). For patients who underwent endovascular intervention, there was a trend of association (p = 0.071) between the lower rate of aortic endograft infection and lifelong antibiotic use. CONCLUSION: Infective native aortic aneurysms are life-threatening. The pooled in-hospital mortality rate of the open surgical repair group was significantly higher than that of the endovascular intervention group, whereas the rate of the aortic VGEI in the open surgical repair group was significantly lower than that in the endovascular intervention group. Regardless of whether open surgical repair or endovascular intervention is performed, better long-term outcomes can be achieved with aggressive antibiotic treatment, which is especially important for patients who undergo endovascular intervention.

Aortic endograft infection by Mycobacterium abscessus subsp. massiliense with acquired clarithromycin resistance: a case report.

BACKGROUND: Mycobacterium abscessus subsp. massiliense (MMA) comprises a group of non-tuberculous, rapidly growing mycobacteria. Although MMA can cause pulmonary diseases, surgical site infections, and disseminated diseases, aortic endograft infection has not been reported. Here, we describe the first case of aortic endograft infection caused by MMA. CASE PRESENTATION: Two months after stent-graft insertion for an abdominal aortic aneurysm, an 85-year-old man was admitted with fever and abdominal pain and was diagnosed with aortic endograft infection. Despite 14 days of meropenem and vancomycin intravenous administration, periaortic fluid pooling increased as compared to that before antibiotic administration. The abscess was drained, and fluorescent acid-fast staining of the abscess fluid revealed bacilli. We conducted genetic tests on the genes hsp65, rpoB, and sodA, performed Whole Genome Sequencing (WGS), and identified the organism as MMA. Intravenous imipenem-cilastatin (IPM/CS), amikacin (AMK), and oral clarithromycin (CAM) were administered. After 2 months, oral CAM and sitafloxacin were administered because the abscess had decreased in size. However, after 6 weeks, the abscess increased in size again. Antimicrobial susceptibility testing of the drainage fluid from the abscess resulted in the isolation of an MMA strain that had acquired resistance to CAM. Intravenous IPM/CS, AMK, and oral linezolid were added to the treatment regimen along with oral CAM and STFX. However, he was not fully cured and died 6 months later. Neither the full-length erythromycin ribosome methyltransferase (erm)(41) gene nor the rrl or rpIV gene mutations were found by Sanger sequencing in the pre- and post-treatment strains. Whole-genome sequence analysis of the post-treatment strain revealed mutations in genes with no previous reports of association with macrolide resistance. CONCLUSIONS: Aortic endograft infection caused by MMA strain is extremely rare; nonetheless, MMA should be suspected as the causative microorganism when broad-spectrum antimicrobials are ineffective.

Abdominal aortic endograft infection with Clostridium difficile.

OBJECTIVES: The increase in endovascular aortic aneurysm repair has led to increasing incidence of aortic endograft infections. Additionally, more atypical organisms are being identified as pathogens. We report on a rare aortic endograft infection to further characterize and understand these infections. METHODS: We report a Clostridium difficile culture-positive aortic endograft infection in an 82-year-old male 3 years after endovascular abdominal aortic aneurysm repair. RESULTS: The patient underwent successful open, complete explant of his endograft and in-situ repair using a rifampin-soaked Dacron graft. He continues to do well. CONCLUSIONS: Aortic endograft infections are a complex problem further complicated by rare and virulent infections. Unless the patient is at prohibitive risk, the management of infected aortic endografts is surgical graft explant and in-situ or extra-anatomic reconstruction due to the exceedingly high mortality rate with non-operative management.

An unusual case of Cardiobacterium valvarum causing aortic endograft infection and osteomyelitis.

BACKGROUND: HACEK (Haemophilus spp., Aggregatibacter spp., Cardiobacterium spp., Eikenella corrodens, and Kingella spp.) group organisms are responsible for 0.8% to 6% of all infective endocarditis cases, with Cardiobacterium spp. being the third most commonly implicated HACEK microorganism. Within this genus is Cardiobacterium valvarum (C. valvarum), a novel organism described in 2004. To date, only 15 cases of C. valvarum infection have been reported in the English-language literature, and have primarily been cases of infective endocarditis in patients with valvular disease. C. valvarum has not been reported to cause infections spreading to the surrounding bone. CASE PRESENTATION: We present a case of a 57-year-old man with a history of aortic dissection followed by aortic endograft replacement who presented with back pain. He was found to have radiographic evidence of an infected aortic endograft, along with vertebral osteomyelitis, discitis, and epidural phlegmon. Blood cultures identified C. valvarum as the causative organism. The patient was treated with ceftriaxone and surgical intervention was deferred due to the patient's complex anatomy. His course was complicated by septic cerebral emboli resulting in cerebrovascular accident. CONCLUSIONS: This case report highlights C. valvarum, a rare and emerging HACEK group microorganism that warrants consideration in high-risk patients with evidence of subacute infection and disseminated disease. While C. valvarum classically presents as infective endocarditis, extra-cardiac manifestations have also been described. As demonstrated in this case, endograft involvement and osteomyelitis may occur in rare circumstances.

Preservation of renal perfusion by hepatorenal and splenorenal bypasses before explantation of an infected abdominal aortic endograft.

We report the case of an 82-year-old patient with an infected abdominal aortic endograft who presented with a right psoas abscess and lumbar osteomyelitis. The psoas abscess was drained percutaneously. Fluid obtained grew Fusobacterium nucleatum. The patient, an active and highly functional individual, wished to pursue definitive management. The infected endograft was surgically removed, and the aorta was ligated above the renal arteries after staged axillary-bifemoral, hepatorenal, and splenorenal bypasses.

Aortic Endograft Infection with Mycobacterium chimaera and Granulicatella adiacens, Switzerland, 2014.

We describe an aortic endograft infection caused by Mycobacterium chimaera and Granulicatella adiacens, successfully treated with prolonged antimicrobial drug therapy after complete explantation of the infected endoprosthesis and extra-anatomical reconstruction. Whole-genome sequencing analysis did not indicate a close relationship to bacterial strains known to cause infections after cardiac surgery.

The Case of the Neighbour's Cat Causing a Symptomatic (Mycotic) Aortic Aneurysm and an Infected Endograft.

INTRODUCTION: Aortic endograft infection is a rare but serious complication following endovascular aneurysm repair. An unusual presentation associated with an uncommon organism is reported. CASE REPORT: A 69 year old female was prescribed but failed to complete a full course of co-amoxiclav following a forearm cat bite. Nine days later she was admitted with pyrexia, left flank pain, and haematuria. Empiric treatment for a urinary tract infection was started. Pasteurella multocida was isolated from blood culture performed during this attendance. Imaging demonstrated hydronephrosis and a 5.5 cm aortic aneurysm with features of impending leak. Emergency endovascular repair was performed without immediate complication. Four weeks following stent graft insertion, the patient was readmitted with loss of consciousness. Imaging demonstrated an infected graft with an associated psoas abscess. The endograft was explanted and reconstruction performed with the femoral vein. Only at this point was the history of a cat bite and positive blood cultures elicited and recognised as relevant. CONCLUSION: Detailed history taking can expose unusual sources of infection. Ideally, an infected aortic endograft should be explanted and the septic focus eradicated prior to autogenous aortic reconstruction.

Aortic Endograft Infection by Pasteurella multocida: A Rare Case.

Infection of an aortic endograft is a rare complication following endovascular aneurysm repair. These patients have been treated with explantation of the graft to obtain source control followed by an extra-anatomic bypass to restore circulation. The present case study describes an interesting case of Pasteurella infection involving an aortic endograft managed nonoperatively by percutaneous drainage and graft preservation.