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Efficient neutrophil migration to infection sites plays a vital role in the body's defense against bacterial infections and natural immune responses. Neutrophils have a short lifespan and cannot be mass‐cultured in vitro. Therefore, developing more stable artificial neutrophils (AN) in a controllable manner has become a research focus. However, existing AN lack chemotaxis, which is the ability to migrate toward high‐signal‐concentration positions in a dynamic blood‐ flow environment. Supplying AN with chemotaxis is key to designing AN that are more similar to natural neutrophils in terms of morphology and function. In this study, micrometer‐sized, spherical, biocompatible AN are developed. These AN consist of zeolitic imidazolate framework‐8 nanoparticles encapsulating two enzymes, coacervate droplet frameworks, and outer phospholipid bilayers carrying enzymes. The AN exhibit responsiveness to elevated hydrogen peroxide levels at inflammation sites, actively chemotaxing toward these sites along concentration gradients. They also demonstrate effective combat against Staphylococcus aureus infections. The capabilities of the AN are further validated through in vitro experiments and in vivo evaluations using vascular graft infection models. This study replicates natural neutrophils in terms of chemical composition, functionality, and physiological impact. It introduces new ideas for advancing the development of advanced artificial cells. [ABSTRACT FROM AUTHOR]

Background: Vascular graft infection is a very complex disease. Although complete excision of the infected grafts with extra-anatomic bypass or in situ reconstruction is a general treatment strategy, some concerns including reinfection in the new graft remain. Case Report: An 88 year-old man presented to the hospital with abdominal swelling and bleeding. The patient had undergone revascularization for aorto-iliac occlusive disease twice in the past. The first procedure had been performed 15 years previously, with right ilio-femoral bypass grafting for right iliac artery occlusion and stent implantation for left iliac artery stenosis. The second procedure had been performed 10 years previously, with aorta-to-left femoral and left-to-right femoro-femoral bypass grafting because the terminal aorta, the first ilio-femoral bypass graft, and the stent of the left iliac artery had been occluded. The patient was diagnosed with vascular graft infection, and endovascular therapy was selected as the revascularization method prior to graft excision. It was successfully performed using various devices and techniques, followed by graft excision without critical limb ischemia. Conclusion: This case demonstrates that endovascular therapy prior to graft excision can be an alternative revascularization method for vascular graft infection after bypass surgery for aorto-iliac occlusive disease. [ABSTRACT FROM AUTHOR]

Implant-related infections may need suppressive antibiotic therapy (SAT). We describe a SAT strategy using dalbavancin with therapeutic drug monitoring (TDM). This is a retrospective bicentric study of patients with implant-related infection who received dalbavancin SAT between January 2021 and September 2023. Fifteen patients were included. Median number of injections was 4 (IQR: 2–7). Median time between two reinjections was 57 days (IQR 28–82). Dalbavancin plasma concentrations were above 4 mg/L for 97.9% of dosages (93/95) and above 8 mg/L for 85% (81/95). These results support the use of dalbavancin SAT for implant-related infections. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to assess risk factors of candida-related Vascular Graft Infections (VGIs). Methods: We did a case–control study (1:4) matched by age and year of infection, nested in a cohort of patient with a history of VGIs. Cases were defined by a positive culture for Candida spp. in biological samples and controls were defined by a positive culture for bacterial strains only in biological samples. Risk factors for Candida-related VGIs were investigated using multivariate logistic regression. Mortality were compared using survival analysis. Results: 16 Candida-related VGIs were matched to 64 bacterial-related VGIs. The two groups were comparable regarding medical history and clinical presentation. Candida-related VGIs were associated with bacterial strains in 88% (14/16). Gas/fluid-containing collection on abdominal CT scan and the presence of an aortic endoprosthesis were risk factors for Candidaspp.-related VGIs [RRa 10.43 [1.81–60.21] p = 0.009 RRa and 6.46 [1.17–35.73] p = 0.03, respectively]. Candida-related VGIs were associated with a higher mortality when compared to bacterial-related VGIs (p = 0.002). Conclusions: Candida-related VGIs are severe. Early markers of Candidaspp. infection are needed to improve their outcome. The suspicion of aortic endoprosthesis infection may necessitate probabilistic treatment with antifungal agents. [ABSTRACT FROM AUTHOR]

Abstract Efficient neutrophil migration to infection sites plays a vital role in the body's defense against bacterial infections and natural immune responses. Neutrophils have a short lifespan and cannot be mass‐cultured in vitro. Therefore, developing more stable artificial neutrophils (AN) in a controllable manner has become a research focus. However, existing AN lack chemotaxis, which is the ability to migrate toward high‐signal‐concentration positions in a dynamic blood‐ flow environment. Supplying AN with chemotaxis is key to designing AN that are more similar to natural neutrophils in terms of morphology and function. In this study, micrometer‐sized, spherical, biocompatible AN are developed. These AN consist of zeolitic imidazolate framework‐8 nanoparticles encapsulating two enzymes, coacervate droplet frameworks, and outer phospholipid bilayers carrying enzymes. The AN exhibit responsiveness to elevated hydrogen peroxide levels at inflammation sites, actively chemotaxing toward these sites along concentration gradients. They also demonstrate effective combat against Staphylococcus aureus infections. The capabilities of the AN are further validated through in vitro experiments and in vivo evaluations using vascular graft infection models. This study replicates natural neutrophils in terms of chemical composition, functionality, and physiological impact. It introduces new ideas for advancing the development of advanced artificial cells.

Introduction Vascular graft infections (VGIs) are challenging and potentially life-threatening complications following femoropopliteal bypasses. The treatments of choice in peripheral VGIs are antimicrobial therapy, surgical excision, and in-situ reconstruction with an autologous superficial vein. An extraanatomical homograft bypass and antimicrobial therapy could be resolutive in patients presenting with recurrent VGIs and unavailable autologous veins.Case Report We present the case of a 74-year-old Caucasian man with a history of a below-the-knee (BTK) right femoropopliteal bypass using polytetrafluoroethylene (PTFE) for chronic peripheral artery disease (Rutherford Grade 3). He presented at the emergency department with septic arthritis of the right knee involving the previous PTFE femoropopliteal bypass. The graft was excised, and an insitu saphenous vein BTK femoropopliteal bypass was performed. Due to multiple recurrences of graft infection of the proximal anastomosis, an extra-anatomical cryopreserved arterial homograft reconstruction from the external iliac artery to the profunda femoral artery was necessary as a definitive treatment. At three years follow-up the patient is alive, with patency of both vascular reconstructions.Conclusion Despite aggressive treatment, managing vascular graft infections can be challenging, typically requiring a blend of surgical and medical interventions. Patient-specific surgical approaches, such as graft removal, infected tissue debridement andextra-anatomical reconstruction with biological grafts is crucial. In those patients with unavailable autologous veins, consideration could be given to a cryopreserved homograft due to its resistance against infections.

Hybrid thoracic endovascular aortic repair (TEVAR) has been proved to be an effective and reliable treatment option for aortic arch diseases requiring extension of the proximal landing zone. However, hybrid TEVAR was associated with potential risk of post-operative complications, including cerebral infarction, endoleaks and paraplegia. Here we reported a rare case of bypass graft infection complicated with mitral valve aneurysm and perforation following landing zone 2 hybrid TEVAR procedure, who presented with symptoms of fever, major bleeding and anastomotic pseudoaneurysm and received emergency bypass graft removal and stent implantation with acceptable short and midterm follow-up results.

Histoplasma vascular graft infection (VGI) is rarely reported, with only a handful of instances documented in the existing literature. Reporting Histoplasma VGI cases is important as they demonstrate previous treatment strategies and their outcomes. In this paper, we report a case of disseminated histoplasmosis with ascending aortic graft infection. Conservative therapy was attempted initially but failed, and our patient eventually required surgical graft explantation. Our case demonstrates the challenges in diagnosing and managing VGI caused by Histoplasma capsulatum.

Key Clinical Message After a Bentall surgery, there is a small chance of developing a serious complication called vascular graft infection. 18F‐FDG PET/CT, a new and accurate diagnostic tool, can help detect it early, especially if the symptoms are unusual. Abstract A 14‐year‐old boy who had undergone Bentall surgery 1 year prior presented with symptoms of fever, chills, loss of appetite, and weight loss over the course of a month. The initial Bentall surgery was performed due to an aneurysm of the thoracic aorta, along with severe aortic valve insufficiency and moderate aortic valve stenosis. The patient was referred to the PET/CT department for evaluation of possible endarteritis or infection of Dacron graft, which had been reported in trans‐esophageal echocardiography as suspicious findings. Despite normal blood tests, blood cultures, and other imaging modalities, the 18F‐FDG PET/CT confirmed the diagnosis of vascular graft infection. This diagnostic tool allowed for timely and appropriate treatment and prevention of possible complications.

Abstract Background Diagnosis of aortic graft infections (AGI) is challenging. Here, we report a case of AGI with splenomegaly and splenic infarction. Case presentation A 46-year-old man who underwent total arch replacement for Stanford type A acute aortic dissection one year prior presented to our department with fever, night sweat, and a 20-kg weight loss over several months. Contrast-enhanced computed tomography (CT) revealed splenic infarction with splenomegaly, fluid collection, and thrombus around the stent graft. Positron emission tomography-CT (PET-CT) revealed abnormal 18F-fluorodeoxyglucose uptake in the stent graft and spleen. Transesophageal echocardiography revealed no vegetations. The patient was diagnosed with an AGI and underwent graft replacement. Blood and tissue cultures in the stent graft yielded Enterococcus faecalis. After the surgery, the patient was successfully treated with antibiotics. Conclusions Splenic infarction and splenomegaly are the clinical findings of endocarditis but are rare in graft infection. These findings could be helpful to diagnose graft infections, which is often challenging.

Key Clinical Message: After a Bentall surgery, there is a small chance of developing a serious complication called vascular graft infection. 18F‐FDG PET/CT, a new and accurate diagnostic tool, can help detect it early, especially if the symptoms are unusual. A 14‐year‐old boy who had undergone Bentall surgery 1 year prior presented with symptoms of fever, chills, loss of appetite, and weight loss over the course of a month. The initial Bentall surgery was performed due to an aneurysm of the thoracic aorta, along with severe aortic valve insufficiency and moderate aortic valve stenosis. The patient was referred to the PET/CT department for evaluation of possible endarteritis or infection of Dacron graft, which had been reported in trans‐esophageal echocardiography as suspicious findings. Despite normal blood tests, blood cultures, and other imaging modalities, the 18F‐FDG PET/CT confirmed the diagnosis of vascular graft infection. This diagnostic tool allowed for timely and appropriate treatment and prevention of possible complications. [ABSTRACT FROM AUTHOR]

Cardiovascular infections are the most severe and potentially lethal among the persistent focalized Coxiella burnetii infections. While aortic infections on aneurysms or prostheses are well-known, with specific complications (risk of fatal rupture), new non-aortic vascular infections are increasingly being described thanks to the emerging use of 18-fluorodeoxyglucose positron emission tomography (18F-FDG PET-scan). Here, we describe an infection of a femoro-popliteal bypass that would not have been diagnosed without the use of PET-scan. It is well-known that vascular prosthetic material is a site favorable for bacterial persistence, but the description of unusual anatomical sites, outside the heart or aorta, should raise the clinicians' awareness and generalize the indications for PET-scan, with careful inclusion of the upper and lower limbs (not included in PET-scan for cancer), particularly in the presence of vascular prostheses. Future studies will be needed to precisely determine their optimal management. [ABSTRACT FROM AUTHOR]

Vascular graft infections are a severe complication in vascular surgery, with a high morbidity and mortality. Prevention and treatment involve the use of antibiotic- or antiseptic-impregnated artificial vascular grafts, but currently, there are no commercially available infection-proof small-diameter vascular grafts (SDVGs). In this work we investigated the antimicrobic activity of two SDVGs prototypes loaded with tobramycin and produced via the electrospinning of drug-doped PLGA (polylactide-co-glycolide) solutions. Differences in rheological and conductivity properties of the polymer solutions resulted in non-identical fibre morphology that deeply influenced the hydration profile and consequently the in vitro cumulative drug release, which was investigated by using a spectrofluorimetric technique. Using DDSolver Excel add-in, modelling of the drug release kinetic was performed to evaluate the release mechanism involved: Prototype 1 showed a sustained and diffusive driven drug release, which allowed for the complete elution of tobramycin within 2 weeks, whereas Prototype 2 resulted in a more extended drug release controlled by both diffusion and matrix relaxation. Time-kill assays performed on S. aureus and E. coli highlighted the influence of burst drug release on the decay rate of bacterial populations, with Prototype 1 being more efficient on both microorganisms. Nevertheless, both prototypes showed good antimicrobic activity over the 5 days of in vitro testing. [ABSTRACT FROM AUTHOR]

Introduction: First described in 1937, Q fever remains a relatively new disease, with much to be learned about its presentation and diagnosis. Due to its role in the development of aortic aneurysms and vascular graft infections, its implications in the vascular domain have become increasingly reported. This is a report of two cases of vascular complications associated with Coxiella burnetii infection, and the challenges in managing their unique presentations. Reports: Case 1: A 70 year old man with a prosthetic aortobiiliac graft and past Q fever infection presented with acute sepsis. Abdominal computed tomography (CT) showed soft tissue thickening and stranding around the graft, and locules of gas within the vessel. Pelvic magnetic resonance imaging (MRI) revealed a chain of abscesses within the right gluteal region, of which aspirate grew Prevotella oris and Escherichia coli. Open explanation of the aortic graft and replacement by superficial femoral vein was performed. Tissue culture confirmed a polymicrobial infection, and PCR of the aortic wall and pre-aortic lymph node was positive for Q fever. He was treated for recrudescent Q fever infection with a good outcome and recovery. Case 2: A 73 year old man had an incidental abdominal aortic aneurysm (AAA) identified at the time of Q fever diagnosis. Following an incomplete course of doxycycline and hydroxychloroquine, the aneurysm rapidly progressed, leading to presentation with right flank pain. Fluorodeoxyglucose (FDG) positron emission tomography (PET) showed multiple foci of uptake within the aneurysm wall. Open AAA repair with a polyester graft was performed, with AAA tissue positive for Q fever on PCR. The operation was successful, with the patient continuing clearance therapy at time of writing. Discussion: Q fever infection poses serious implications for patients with vascular grafts and AAAs, and thus, should be considered in the differential diagnosis of mycotic aortic aneurysms and in aortic graft infections.

ABSTRACT: A vascular graft or endograft infection (VGEI) is a severe complication that can occur after vascular graft or endograft surgery and is associated with high morbidity and mortality rates. A multidisciplinary approach, consisting of a team of vascular surgeons, infectious diseases specialists, medical microbiologists, radiologists, nuclear medicine specialists, and hospital pharmacists, is needed to adequately diagnose and treat VGEI. A structured diagnostic, antibiotic, and surgical treatment algorithm helps clinical decision making and ultimately aims to improve the clinical outcome of patients with a VGEI.

Background: Diagnosis of aortic graft infections (AGI) is challenging. Here, we report a case of AGI with splenomegaly and splenic infarction. Case presentation: A 46-year-old man who underwent total arch replacement for Stanford type A acute aortic dissection one year prior presented to our department with fever, night sweat, and a 20-kg weight loss over several months. Contrast-enhanced computed tomography (CT) revealed splenic infarction with splenomegaly, fluid collection, and thrombus around the stent graft. Positron emission tomography-CT (PET-CT) revealed abnormal 18F-fluorodeoxyglucose uptake in the stent graft and spleen. Transesophageal echocardiography revealed no vegetations. The patient was diagnosed with an AGI and underwent graft replacement. Blood and tissue cultures in the stent graft yielded Enterococcus faecalis. After the surgery, the patient was successfully treated with antibiotics. Conclusions: Splenic infarction and splenomegaly are the clinical findings of endocarditis but are rare in graft infection. These findings could be helpful to diagnose graft infections, which is often challenging. [ABSTRACT FROM AUTHOR]

Purpose: After endovascular aneurysm repair (EVAR), an increased [18F]FDG uptake may be observed at PET/CT, being common to both vascular graft/endograft infection (VGEI) and sterile post-surgical inflammation. Increased non-specific metabolic activity, due to foreign body reaction, can persist for several years after surgery, thus complicating the interpretation of PET/CT studies. In this paper, we aimed to assess [18F]FDG distribution at different time-points after the implant of abdominal Endurant® endografts in patients without suspicion of infection. Methods: We retrospectively evaluated [18F]FDG/CT in 16 oncological patients who underwent abdominal aortic aneurysm exclusion with Endurant® grafts. Patients had no clinical suspicion of infection and were followed up for at least 24 months after scan. [18F]FDG PET/CT scans were interpreted using both visual and semi-quantitative analyses. Results: The time between the EVAR procedure and [18F]FDG PET/CT ranged between 1 and 36 months. All grafts showed mild and diffuse [18F]FDG uptake without a focal pattern. Mean values of SUVmax were 2.63 ± 0.48 (95% CI 2.38–2.88); for SUVmean 1.90 ± 0.33 (95% CI 1.72–2.08); for T/B ratios 1.43 ± 0.41 (95% CI 1.21–1.65). SUVmax and SUVmean were not correlated to the time elapsed from the procedure, but we observed a declining trend in T/B ratio over time. Conclusions: Endovascular implant of Endurant® grafts does not cause a significant inflammatory reaction. The evidence of faint and diffuse [18F]FDG uptake along the graft can reliably exclude an infection, even in early post-procedural phases. Therefore, in patients with a low probability of VGEI, [18F]FDG PET/CT can also be performed immediately after EVAR. [ABSTRACT FROM AUTHOR]

• Vascular graft or endograft infection (VGEI) is associated with high morbidity and mortality rates. • VGEI patients should be managed within a multidisciplinary team. • A structural diagnostic and treatment algorithm for VGEI is mandatory. A vascular graft or endograft infection (VGEI) is a severe complication that can occur after vascular graft or endograft surgery and is associated with high morbidity and mortality rates. A multidisciplinary approach, consisting of a team of vascular surgeons, infectious diseases specialists, medical microbiologists, radiologists, nuclear medicine specialists, and hospital pharmacists, is needed to adequately diagnose and treat VGEI. A structured diagnostic, antibiotic, and surgical treatment algorithm helps clinical decision making and ultimately aims to improve the clinical outcome of patients with a VGEI. [ABSTRACT FROM AUTHOR]

Introduction: High suspicion for infective endocarditis is driven by fever and positive blood cultures in the absence of an alternative focus of infection. This case underlines the importance of exploring other more obvious sources of bacteremia to avoid unnecessary tests and delays in diagnosis. In cases of inconclusive echocardiography results, imaging should be repeated. Case report: 59-year-old patient with diabetes and hypertension was admitted for sepsis, unilateral leg pain and plantar rash. Medical history includes aortobifemoral reparation of infrarenal aortic aneurysm 19 years ago and recurrent leg abscesses with prolonged periods of antimicrobial and probiotic therapy. Blood cultures found Lactobacillus rhamnosus and Candida glabrata. Positive blood cultures and clear Janeway lesions (Figure 1) indicated transesophageal echocardiography (TEE) which showed competent aortic valve with small hyperechogenic lesion (7mm X 6 mm) on base of left coronary cusp (Figure 2). TEE was repeated after 2 weeks of effective antimicrobial therapy, showing no change of suspected valvular lesion. Patient clinically improved and repeated blood cultures were negative. Further workup (including FDG-PET/CT) found intensive tracer uptake in the region of implanted aortic prosthesis. The surgeon opted for prolonged course of antimicrobial therapy. Unfortunately, only 4 days after completion of therapy the patient was septic with positive blood cultures. The operation was inevitable and aortointestinal fistula, graft infection and thrombosis were found. Partial graft replacement and bowel reconstruction were conducted. Conclusion: Even in patients with highly specific findings for endocarditis like skin lesions and positive blood cultures, workup and therapy should be clinically guided. Bizarre blood culture isolates in our patient are easily explained when we know complete course of disease. [ABSTRACT FROM AUTHOR]

Angioinvasive aspergillosis is a fungal infection that rarely involves vascular grafts. This case illustrates a patient with a history of aortic arch Dacron graft reconstruction presenting with acute bilateral lower extremity ischemia. The patient underwent emergent open thromboembolectomy. The intraluminal contents had an atypical appearance for thromboembolism, and histologic examination was consistent with aspergillosis. Cardiac computed tomography and transesophageal echocardiography showed an aortic arch graft vegetation. Aortic graft excision and reconstruction were performed for control of the fungal source. Investigation into the etiology of thromboembolism should include consideration for septic emboli in patients with indwelling vascular grafts. When suspected, graft excision should be considered for definitive management.

Lawsonella clevelandensis is a fastidious Gram-positive, partially acid-fast, anaerobic, catalase positive bacterium that has been reported to be a rare cause of abdominal, breast, spinal, and liver abscesses. Here, three L. clevelandensis vascular graft infections (VGIs) and cardiac infections are reported.

Vascular graft infections (VGI) pose a significant challenge in vascular surgery, characterized by substantial morbidity and mortality. This review delves into the epidemiology, pathogenesis, microbiology, risk factors, and clinical presentation of VGI. It highlights diagnostic criteria and methodologies, including imaging techniques and laboratory tests. Comprehensive management strategies, involving antimicrobial therapy, surgical intervention, and preventive measures, are discussed. Emphasis is placed on the multidisciplinary approach required for effective treatment, alongside emerging trends in VGI microbiology and innovative therapeutic options. This review article aims to provide a detailed understanding of VGI for improved clinical outcomes., Competing Interests: Disclosures Declaration of artificial intelligence (AI) and AI-assisted technologies in the writing process: During the preparation of this work, the authors used Chatgpt /AI language model in order to improve readability and language of the material, since English is not the first language of the primary authors., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Graft infections of supra-aortic bypasses are rare, but often life-threatening. Guidelines for treatment of graft infections recommend systemic antibiotics and complete graft removal, followed by in-situ or extra-anatomic revascularisation., Methods: Based on case report, literature search was performed on Medline, Google Scholar and Web of Science databases, focussing on infected supra-aortic bypass reconstructions. Inclusion criterium was prosthetic graft infection, excluding stent and carotid patch infections., Results: A 68-year old man with clinically infected subclavian-subclavian bypass with interposition bypass to left carotid bifurcation, presented at emergency department with manifestation of sepsis. A total graft removal and an extra-anatomical prosthetic reconstruction was created, from right common carotid artery to left carotid bifurcation. Defect of prior left subclavian anastomosis was primarily closed, on right subclavian anastomosis per-operative acute bleeding occured, which was controlled by covered stent through right brachial artery. Literature review identified 16 cases. Different approaches ranging from open repair with autologous (six) or allogenic (two) material, to hybrid techniques (eight) have been described. No re-infections were reported. When comparing different types of approaches, no differences are found concerning overall complications., Conclusion: Complete graft removal with extra-anatomical reconstruction is challenging, but crucial in supra-aortic graft infections. Preservation of parts of vascular prosthesis depends on case-by-case basis, according to infection site and general condition of the patient. But due to rarity, only case reports are available, so no strong recommendations can be formulated. International registries should be initiated to share experiences and provide data for decent analysis of short, mid and long term outcomes.

Aerococcus urinae, a gram-positive, catalase-negative coccus, has emerged as a notable pathogen in clinical microbiology. It is traditionally associated with urinary tract infections in elderly males with underlying urologic conditions. Recently, A. urinae has been implicated in severe invasive infections outside the genitourinary tract including infective endocarditis, vertebral osteomyelitis, peritonitis, lymphadenitis, and discitis. We present the case of 84-year-old male with a history of aortic graft replacement who presented with five days of fever and fatigue. Blood and urine cultures grew gram-positive cocci, identified as A. urinae. Thoracoabdominal contrast-enhanced CT revealed a slightly increased soft tissue shadowing around the prosthetic stent in the ascending aorta, indicating a possible aortic stent-graft infection. Gallium-67 scintigraphy demonstrated inflammation around the prosthetic stent in the ascending aorta consistent with an aortic stent-graft infection. The patient and family opted for conservative treatment and despite a six-week inpatient course of ampicillin, followed by oral amoxicillin, the patient died one week after discharge. This is the first published case of A. urinae causing an aortic stent-graft infection. Clinicians should remain cognizant of the disseminated source of infection in cases of A. urinae bacteremia., Competing Interests: Conflict of interest statement All authors have no conflicts of interest to declare., (Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)

Cardiovascular infections are the most severe and potentially lethal among the persistent focalized Coxiella burnetii infections. While aortic infections on aneurysms or prostheses are well-known, with specific complications (risk of fatal rupture), new non-aortic vascular infections are increasingly being described thanks to the emerging use of 18-fluorodeoxyglucose positron emission tomography (18F-FDG PET-scan). Here, we describe an infection of a femoro-popliteal bypass that would not have been diagnosed without the use of PET-scan. It is well-known that vascular prosthetic material is a site favorable for bacterial persistence, but the description of unusual anatomical sites, outside the heart or aorta, should raise the clinicians’ awareness and generalize the indications for PET-scan, with careful inclusion of the upper and lower limbs (not included in PET-scan for cancer), particularly in the presence of vascular prostheses. Future studies will be needed to precisely determine their optimal management.

Purpose: Consensus on optimal imaging procedure for vascular graft/endograft infection (VGEI) is still lacking and the choice of a diagnostic test is often based on the experience of single centres. This document provides evidence-based recommendations aiming at defining which imaging modality may be preferred in different clinical settings and post-surgical time window. Methods: This working group includes 6 nuclear medicine physicians appointed by the European Association of Nuclear Medicine, 4 vascular surgeons, and 2 radiologists. Vascular surgeons formulated 5 clinical questions that were converted into 10 statements and addressed through a systematic analysis of available literature by using PICOs (Population/problem–Intervention/Indicator–Comparator–Outcome) strategy. Each consensus statement was scored for level of evidence and for recommendation grade, according to the Oxford Centre for Evidence-based Medicine criteria. Results: Sixty-six articles, published from January 2000 up to December 2021, were analysed and used for evidence-based recommendations. Conclusion: Computed tomography angiography (CTA) is the first-line imaging modality in suspected VGEI but nuclear medicine modalities are often needed to confirm or exclude the infection. Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) has very high negative predictive value but it should be performed preferably at least 4 months after surgery to avoid false positive results. Radiolabelled white blood cell (WBC) scintigraphy, given its high diagnostic accuracy, can be performed at any time after surgery. Preamble: The European Association of Nuclear Medicine (EANM) is a professional no-profit medical association that facilitates communication worldwide between individuals pursuing clinical and research excellence in nuclear medicine. The EANM was founded in 1985. EANM members are physicians, technologists, and scientists specializing in the research and practice of nuclear medicine. The EANM will periodically define new guidelines for nuclear medicine practice to help advance the science of nuclear medicine and to improve the quality of service to patients throughout the world. Existing practice guidelines will be reviewed for revision or renewal, as appropriate, on their fifth anniversary or sooner, if indicated. Each practice guideline, representing a policy statement by the EANM, has undergone a thorough consensus process in which it has been subjected to extensive review. The EANM recognizes that the safe and effective use of diagnostic nuclear medicine imaging requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guideline by those entities not providing these services is not authorized. These guidelines are an educational tool designed to assist practitioners in providing appropriate care for patients. They are not inflexible rules or requirements of practice and are not intended, nor should they be used, to establish a legal standard of care. For these reasons and those set forth below, the EANM suggests caution against the use of the current consensus document in litigation in which the clinical decisions of a practitioner are called into question. The ultimate judgement regarding the propriety of any specific procedure or course of action must be made by the physician or medical physicist in the light of all the circumstances presented. Thus, there is no implication that an approach differing from the consensus document, standing alone, is below the standard of care. To the contrary, a conscientious practitioner may responsibly adopt a course of action different from that set forth in the consensus document when, in the reasonable judgement of the practitioner, such course of action is indicated by the condition of the patient, limitations of available resources, or advances in knowledge or technology subsequent to publication of the consensus document. The practice of medicine includes both the art and the science of the prevention, diagnosis, alleviation, and treatment of disease. The variety and complexity of human conditions make it impossible to always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment. Therefore, it should be recognized that adherence to this consensus document will not ensure an accurate diagnosis or a successful outcome. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources, and the needs of the patient, to deliver effective and safe medical care. The sole purpose of this consensus document is to assist practitioners in achieving this objective. [ABSTRACT FROM AUTHOR]

Objectives: To report the midterm outcomes of treating prosthetic peripheral and aortic graft infections using a biosynthetic collagen prosthesis in a tertiary vascular center. Methods: A retrospective analysis of all patients with prosthetic peripheral and aortic graft infections who underwent in situ reconstruction using a biosynthetic collagen prosthesis between March 2015 and November 2020 was conducted. Perioperative and midterm outcomes were analyzed. Results: A biosynthetic collagen prosthesis was used in 19 patients (14 males, median age 66 years) to reconstruct the femoral artery (n = 6), iliac artery (n = 1), and infrarenal aorta (n = 12). All patients were treated for a prosthetic vascular graft infection. The median follow-up period was 26.6 months (range 1–66 months). The 30-day graft failure rate was 15.7% (n = 3), leading to a major amputation in one patient (5.3%). All grafts were occluded aortofemoral reconstructions in patients with occluded superficial femoral artery and were treated by immediate thrombectomy. The 30-day mortality rate was 5.3% (n = 1), and survival after 3 years was 63.2%. The reinfection rate was 5.3% (n = 1). At 13.6 months, the occlusion of a femoral graft was detected in 5.3% (n = 1) and was treated with a new interposition graft. We observed no graft rupture or degeneration during follow-up. Conclusions: Although results of in situ repair with autologous vein seem to be superior with little or none reinfection and low number of occlusions, biosynthetic collagen prostheses show acceptable midterm outcomes in terms of graft occlusion and mortality after prosthetic peripheral and aortic graft infections. Similar to other xenogenous materials, the reinfection rate is low with this prosthesis. With regard to immediate availability and easy handling, the use of a biosynthetic collagen prosthesis might be favorable compared to other replacement materials while treating prosthetic graft infections. [ABSTRACT FROM AUTHOR]

Haemophilus parainfluenzae is a gram-negative coccobacillus that is a part of the normal flora in the human upper airway and sometimes causes infective endocarditis. We present a case of a 68-year-old Japanese man who had vascular graft infection caused by H. parainfluenzae 4 years after surgery for chronic aortic dissection. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing emphasis on efficient and accurate diagnostic testing, exemplified by the American Board of Internal Medicines Choosing Wisely campaign. Nuclear imaging studies can provide early and accurate diagnoses of many infectious disease syndromes, particularly in complex cases where the differential remains broad. This review paper offers clinicians a rational, evidence-based guide to approaching nuclear medicine tests, using an example case of methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia in a patient with multiple potential sources. Fluorodeoxyglucose-positron emission tomography (FDG-PET) with computed tomography (CT) and sulfur colloid imaging with tagged white blood cell (WBC) scanning offer the most promise in facilitating rapid and accurate diagnoses of endovascular graft infections, vertebral osteomyelitis (V-OM), diabetic foot infections, and prosthetic joint infections (PJIs). However, radiologists at different institutions may have varying degrees of expertise with these modalities. Regardless, infectious disease consultants would benefit from knowing what nuclear medicine tests to order when considering patients with complex infectious disease syndromes.

The objective of the present study was to evaluate systemic and local effects of cefepime alone and/or in combination with vancomycin in the prevention of experimentally implanted Dacron and ePTFE vascular grafts infected with Staphylococcus aureus in rat. Ninety healthy adult male Wistar rats were divided into two groups of 45 animals each. Then, each group was subdivided into nine subgroups of 5 animals each. Following anesthesia, in each rat one cm2, sterile Dacron or ePTFE graft was implanted aseptically into dorso-lumbar subcutaneous pocket. The grafts were infected by inoculation of one ml of (5 × 107 CFU/ml) Staphylococcus aureus suspension. The rats received vancomycin or cefepime locally, intraperitoneally, or in combinations. The grafts were removed seven days after implantation and evaluated by quantitative culture. Combinations of cefepime with vancomycin resulted in enhanced efficiency of antibiotics in bacterial growth inhibition. Local vancomycin was more effective than local cefepime in the reduction of graft contamination. A combination of intraperitoneal vancomycin, as well as local cefepime, was more effective than a combination of intraperitoneal cefepime as well as intraperitoneal vancomycin in the Dacron group. Local vancomycin-intraperitoneal cefepime combination could be suggested to prevent Dacron and ePTFE vascular graft infected with Staphylococcus aureus. Local treatment alone, vancomycin for Dacron graft and cefepime for ePTFE graft, and intraperitoneal treatment alone, vancomycin for ePTFE graft, could also be suggested.

Heart infections are not limited to infectious endocarditis. In fact, prosthetic vascular graft infections are among the most severe complications associated with vascular and cardiac surgery. The risk of developing an infection on prosthetic material is estimated to be ~5%. The mortality rate associated with the infection is estimated to be ~10-25% within 30 days of infection and 50% after 1 year. The present article describes a case of a methicillin-sensitive Staphylococcus aureus (MSSA) infection on the prosthetic material following a heart Fontan procedure. To the best of our knowledge, only one other case of extracardiac prosthesis-related infection following Fontan surgery has been reported to date in adults. Prosthetic vascular graft infections (PVGIs) are a rare complication of heart surgery. However, PVGIs can seldomly occur and are burdened by a decreased survival rate. Therefore, physicians need to promptly suspect and recognize such cases. Further studies are required however, in order to determine the feasibility and long-term survival rates of a conservative therapeutic approach. [ABSTRACT FROM AUTHOR]

Background Vascular graft infection (VGI) remains a severe disease with high mortality and relapse rates. We performed a retrospective single-center cohort study to highlight factors associated with long-term all-cause mortality in patients with vascular graft infection. Methods All patients hospitalized in our facility over 10 years for VGI were included. VGI was defined by the presence of a vascular graft or an aortic stent graft (stent or fabric), associated with 2 criteria among clinical, biological, imaging, or microbiological elements in favor of VGI. The primary outcome was all-cause mortality. Empirical antibiotic therapy was considered as appropriate when all involved pathogens were susceptible in vitro to the antibiotics used. The surgical strategy was defined as nonoptimal when the graft was not removed in a late-onset surgery (>3 months) or no surgery was performed. Results One hundred forty-six patients were included. Empirical antibiotic therapy was administered in 98 (67%) patients and considered appropriate in 55 (56%) patients. Surgery was performed in 136 patients (96%) and considered as optimal in 106 (73%) patients. In multivariable analysis, appropriate empirical antibiotic therapy was associated with a lower probability of mortality (hazard ratio, 0.47 [95% confidence interval,.30–.79]; P  = .002). Long-term survival did not differ according to whether the surgical strategy was considered optimal or not (log-rank = 0.66). Conclusions Appropriate empirical antibiotic therapy is a cornerstone of the management of VGI. Whenever possible, antibiotics must be associated with optimal surgical management. However, surgery could potentially be avoided in comorbid patients who are treated with appropriate antibiotics. [ABSTRACT FROM AUTHOR]

Objective: This in vitro study investigates the antimicrobial efficacy of impregnation of commercially available aortic endografts (EG) with rifampicin (RIF) and nanocolloidal silver. Methods: Endografts were flushed with 50 mL of RIF 600 mg, 70 mL of a silver-based aqueous solution (AG), or 50 mL of phosphate-buffered saline (PBS) over 15 minutes. Endografts were then retrieved from the sheath and cut in 1 × 1 cm sized graft units (n = 80 of each impregnation), which were then incubated for 1 hour separately with inoculates containing 106 or 103 bacteria per milliliter (bact/mL) of each of the following bacteria: Staphylococcus epidermidis, Escherichia coli, multisensitive Staphylococcus aureus, and Pseudomonas aeruginosa. After sonication of the graft units, bacterial counts were measured by plating out twice the sonication solution on Mueller-Hinton plates. Results: RIF showed a statistically significant decrease of colony forming units per milliliter for all four bacterial strains in both concentrations compared with PBS and AG, except for 103 bact/mL of E coli. AG showed a significant decrease of colony forming units per milliliter compared with PBS only for 106 bact/mL of E coli and was statistically significantly inferior to RIF for all four bacterial strains in both concentrations with the exception of E coli at a concentration of 103 bact/mL. Conclusions: This in vitro study demonstrated infectivity resistance of aortic EG after flushing with RIF. Moreover, the feasibility of flushing aortic EG with a new silver-based agent could be demonstrated, but without statistically significant antimicrobial efficacy compared with native EG. : Clinical Relevance: Because the number of elective and emergency endovascular procedures on the thoracic and abdominal aorta is continuously increasing, endograft infections in both locations are also more frequently observed. The necessity and use of antimicrobial-impregnated EG in the prophylaxis or treatment of endograft infections has so far neither been discussed in the literature nor addressed in existing guidelines. This is the first study investigating the influence of antiseptic impregnations of commercially available aortic EG on in vitro contamination with bacteria commonly causing vascular graft infections. Owing to proven infectivity resistance, flushing EG with RIF could, despite known limitations, lead to a modification of established therapeutic principles in patients at high risk for aortic graft infections.

Purpose: After endovascular aneurysm repair (EVAR), an increased [18F]FDG uptake may be observed at PET/CT, being common to both vascular graft/endograft infection (VGEI) and sterile post-surgical inflammation. Increased non-specific metabolic activity, due to foreign body reaction, can persist for several years after surgery, thus complicating the interpretation of PET/CT studies. In this paper, we aimed to assess [18F]FDG distribution at different time-points after the implant of abdominal Endurant® endografts in patients without suspicion of infection. Methods: We retrospectively evaluated [18F]FDG/CT in 16 oncological patients who underwent abdominal aortic aneurysm exclusion with Endurant® grafts. Patients had no clinical suspicion of infection and were followed up for at least 24 months after scan. [18F]FDG PET/CT scans were interpreted using both visual and semi-quantitative analyses. Results: The time between the EVAR procedure and [18F]FDG PET/CT ranged between 1 and 36 months. All grafts showed mild and diffuse [18F]FDG uptake without a focal pattern. Mean values of SUVmax were 2.63 ± 0.48 (95% CI 2.38–2.88); for SUVmean 1.90 ± 0.33 (95% CI 1.72–2.08); for T/B ratios 1.43 ± 0.41 (95% CI 1.21–1.65). SUVmax and SUVmean were not correlated to the time elapsed from the procedure, but we observed a declining trend in T/B ratio over time. Conclusions: Endovascular implant of Endurant® grafts does not cause a significant inflammatory reaction. The evidence of faint and diffuse [18F]FDG uptake along the graft can reliably exclude an infection, even in early post-procedural phases. Therefore, in patients with a low probability of VGEI, [18F]FDG PET/CT can also be performed immediately after EVAR.

Vascular graft infection with its morbidity and mortality has tormented the world of vascular reconstruction overlong. India despite carrying a sizable burden of patients requiring vascular reconstruction has minimal research on the subject. We attempted to chronicle clinical profiles, symptom variability, risk factors, prophylactic measures, and various therapeutic options extended to patients with vascular graft infection, in this medical record-based case series analysis, of a decade (years 2010–2020), of patients presenting with vascular graft infections. Statistical comparison was done with chi-square and Fisher's exact probability test. A total of 70 patients presented with vascular graft infection, 92.9% men and 7.1% women (mean age of 58 SD 11.8 years). Diabetes and coronary artery disease were the commonest comorbid conditions (24.7% each). The most common site of infection was the groin, and femoropopliteal bypass graft was the most infected segment (48.5%). The average time interval from index surgery to presentation with infection was 308 days. Early graft infection was seen in 60% patients, with extra-cavitary graft infections manifesting earlier than others. Local symptoms with discharging sinuses and cellulitis were common clinical presentations. Staphylococcus aureus was the commonest organism isolated (31.4%). A total of 58.5% patients underwent graft explantation and 40% were managed conservatively. Incidence of infection in patients who underwent immediate post-operative re-intervention was statistically significant when compared with Bunt's classification (P value < 0.05). The distribution of incidence of post-operative infection differed significantly across various sites and the type of graft material used (P value < 0.05). Prosthetic vascular grafts provide unparalleled benefit to a patient in maintenance of life and limb. Our Indian experience of a decade when summed up reflects that extra-cavitary graft infections express early and anatomical predisposition of the groin makes femoropopliteal segment the worst affected in VGI. Remote infections and re-interventions are hidden caveats of VGI. Apt to say that "Aegrescit medendo"—"the cure is worse than the disease"—holds good for vascular graft infections. [ABSTRACT FROM AUTHOR]

In Canada, tissue distribution is managed by provincial entities. In 2014, Hema-Quebec established a cryopreserved vascular tissue bank accessible to all Canadian hospitals. The objectives of this report were to review the first 5 years of activity of Hema-Quebec's vascular bank and to briefly assess the competitiveness of its products. Deceased donors, ages 15 to 60, were screened for common blood-borne diseases. Grafts were treated in a triple-antibiotic solution at 35°C before preservation at –100°C. Hema-Quebec's vascular graft records were analyzed from 2014 to 2019 inclusively. The average donor age was 35 years old and 78% of donors were men. Overall, 63% of harvested grafts cleared the quality management system. Positive microbial cultures and morphologic defects were the major reasons for graft discard. As such, a total of 60 grafts were delivered between 2016 and 2019 to 8 hospital centers. Moreover, the bank achieved a mean activity increase of 55% per year and Hema-Quebec's homografts were 48% less costly compared with similar homographs from for-profit organizations. Our findings demonstrate that Hema-Quebec has established a viable cryopreserved vascular tissue bank with steady increase in activity and an acceptable graft discard rates and pricing. Based on our findings, we recommend that efforts should be directed to expand the tissue bank graft distribution outside the province of Quebec. [ABSTRACT FROM AUTHOR]

Different graft materials have been proposed for in situ reconstruction in the setting of vascular graft infection (VGI). We analyzed the long-term outcomes after in situ aortoiliac reconstruction with cryopreserved allografts. We performed a retrospective analysis of patients who had undergone in situ aortoiliac reconstruction with cryopreserved arterial allografts for VGI from 2000 to 2015. The end points were the perioperative and long-term mortality and graft-related complications, including stenosis, occlusion, pseudoaneurysm, and reinfection. A total of 33 patients (91% male) with a median age of 67 years (range, 53-83 years) had undergone in situ aortoiliac reconstruction with cryopreserved allografts. The 30-day mortality was 6% (n = 2); both deaths were related to the allograft (one early allograft–enteric fistula and one graft rupture). Another two patients had experienced early (≤30 days) graft-related events (one allograft–enteric fistula and one graft limb occlusion), for an early graft-related complication rate of 12% (n = 4). Of the 31 discharged patients, 13 (42%) had died after a median of 47 months (range, 2-97 months). The median follow-up for the 18 remaining patients was 96 months (range, 10-146 months). The estimated survival at 1, 3, and 5 years was 88%, 81%, and 66%, respectively. Nine patients (29%) had experienced at least one of the following graft-related events during follow-up, including graft stenosis requiring intervention in five (16%), graft occlusion in four (13%), pseudoaneurysm in three (10%), and reinfection in two patients (6%). The estimated freedom from any first graft-related event at 1, 3, and 5 years was 78%, 71%, and 62%, respectively. The estimated primary patency and primary assisted patency at 1 and 3 years was 87% and 79%, and 90% and 83%, respectively. In situ aortoiliac reconstruction with cryopreserved allografts to treat VGI was associated with relevant perioperative graft-related complications. Although the reinfection rate was acceptable, other graft-related complications were frequent in the long term, in particular, graft occlusion and stenosis. [ABSTRACT FROM AUTHOR]

Mathilde Puges,1 Armelle Ménard,2,3 Xavier Berard,4 Magalie Geneviève,5 Jean-Baptiste Pinaquy,6 Sophie Edouard,7 Sabine Pereyre,3,8 Charles Cazanave1,81Service des Maladies Infectieuses et Tropicales, Centre Hospitalier Universitaire de Bordeaux, Groupe Hospitalier Pellegrin, Bordeaux, F-33000, France; 2Unité Mixte de Recherche 1053 Bordeaux Research in Translational Oncology, BordeAux Research In Translational Oncology, University Bordeaux, Institut National de la Santé et de la Recherche Médicale, F-33076, France; 3Service de Bactériologie, Centre Hospitalier Universitaire de Bordeaux, Groupe Hospitalier Pellegrin, Bordeaux, F-33000, France; 4Service de Chirurgie Vasculaire, Hôpital Pellegrin, Centre Hospitalier Universitaire de Bordeaux, Groupe Hospitalier Pellegrin, Bordeaux, F-33000, France; 5Service de Néphrologie, Polyclinique Francheville, Périgueux, F-24000, France; 6Service de Médecine Nucléaire, Centre Hospitalier Universitaire de Bordeaux, Hôpital du Haut-Lévêque, Pessac, F-33600, France; 7IHU Méditerranée-Infection, Unité Mixte de Recherche Microbes Evolution Phylogeny and Infections, Aix-Marseille Université, Institut de Recherche et Développement, Assistance Publique - Hôpitaux de Marseille, Marseille, France; 8University Bordeaux, Institut National de la Recherche Agronomique, Unité Sous Contrat Equipe D’accueil 3671, Mycoplasma and Chlamydia Infections in Humans, Bordeaux, F-33000, FranceAbstract: Bartonella alsatica is a wild rabbit pathogen causing bacteremia rarely reported in humans, with only three cases published so far, including one lymphadenitis and two endocarditis cases. Here, we report the case of a 66-year-old man who suffered from acute renal failure due to a membranoproliferative glomerulonephritis. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) showed diffuse FDG uptake around the aortobifemoral graft with no indication of infection. A white blood cell scan showed an accumulation of labeled neutrophils on the left femoral part of the graft. The patient underwent surgery and an abscess around the left iliac part of the graft was found intraoperatively. Intraoperative samples were all negative, but 16S rRNA gene-based PCR was positive, and the sequence was positioned among the Bartonella species cluster. Specific PCRs targeting groEL/hsp60, rpoB and gltA genes were performed and led to the identification of B. alsatica. Accordingly, indirect immunofluorescence serological analyses were positive for Bartonella henselae and Bartonella quintana. The patient had a history of regularly hunting wild rabbits. He was treated with 100 mg of doxycycline twice a day for six months and his renal function significantly improved with no sign of persistent infection. This case highlights the contribution of serology assays and molecular-based methods in prosthetic vascular graft infection diagnosis.Keywords: vascular graft infection, Bartonella alsatica, 16S rRNA PCR, membranoproliferative glomerulonephritis

Q fever, a zoonotic infection caused by Coxiella burnetii, can present with a wide spectrum of clinical manifestations. The organism is typically transmitted from sheep, goats, or cattle to humans via contaminated aerosols. On average, 1–5% of patients with acute Q fever will develop chronic infection months to decades after their primary infections. We report a case of a chronic vascular graft infection due to Coxiella burnetii in a 61-year-old man without direct exposure to animals who presented with recurrent fever. Indium-111-labeled white blood cell scan with single-emission positron computed tomography demonstrated findings suggesting a graft infection. C. burnetii phase I and phase II IgG antibody titers were > 1:32,768 and polymerase chain reaction performed on the explanted graft was positive for C. burnetii. Q fever should be considered in the differential diagnosis of vascular infections in patients who have a pre-existing lesion such as an aneurysm, or vascular prosthesis even in the absence of a history of direct animal exposure.

Histoplasma vascular graft infection (VGI) is rarely reported, with only a handful of instances documented in the existing literature. Reporting Histoplasma VGI cases is important as they demonstrate previous treatment strategies and their outcomes. In this paper, we report a case of disseminated histoplasmosis with ascending aortic graft infection. Conservative therapy was attempted initially but failed, and our patient eventually required surgical graft explantation. Our case demonstrates the challenges in diagnosing and managing VGI caused by Histoplasma capsulatum ., (© 2024 The Authors.)

Introduction: Vascular graft infection is a life threatening situation with significant morbidity and mortality. Bacterial graft infection can lead to false aneurysms, bleeding and sepsis. There are a lot of risky situations where grafts can become infected. It is therefore highly desirable to have a vascular graft that is resistant to infection. In this retrospective clinical study, a silver-impregnated vascular graft was evaluated in various indications. Methods: Our study included a total of 71 patients who received a silver-impregnated vascular graft during the period from 2013 to 2018. Patients had an aortoiliac localization of vascular graft in 61 cases (86%), and a peripheral localization on the lower limbs in 10 cases (14%). Indications for the use of these special vascular grafts were trophic lesions or gangrene in the lower limbs in 24 cases (34%), suspicious mycotic abdominal aortic aneurysm (mAAA) in 4 cases (5.5%), salmonela aortitis or aneurysms in 4 cases (5.5%), infection of the previous vascular graft in 11 cases (15.5%), other infections in 12 cases (17%), AAA rupture in 10 cases (14%) and other reasons (pre-transplant condition, multiple trauma, graft-enteric fistula) in 6 cases (8.5%). Thirty-day mortality, morbidity, the need for reintervention and amputation, primary and secondary graft patency, and finally the presence of a proven vascular graft infection were evaluated. Results: The 30-day mortality was 19.7%, and morbidity was 42.2%. The primary patency of the vascular graft was 91.5%. Reoperation was necessary in 10 cases (14%) and amputation was necessary in 10 cases (14%). The median length of hospital stay was 13 days and the mean follow-up period was 48 ± 9 months. During the follow-up period, six patients (8.5%) died from reasons unrelated to surgery or without any relation to the vascular graft. Secondary patency after one year was 88%. Infection of the silver graft was observed in three patients (4.2%). Conclusions: Based on our results, the silver graft is a very suitable alternative for solving infectious, or potentially infectious, situations in vascular surgery. In particular, in urgent or acute cases, a silver graft is often the only option.

La infección de las prótesis vasculares es una complicación temible por su alta morbimortalidad, en la que el diagnóstico precoz es imprescindible. Evaluamos la utilidad de la gammagrafía con leucocitos marcados con 99mTc-HMPAO y SPECT/TC (GLM-SPECT/TC) en el diagnóstico de esta patología. Analizamos retrospectivamente 30 GLM-SPECT/TC realizadas en pacientes con sospecha de infección de prótesis vasculares. Se consideró como resultado positivo la captación del radiofármaco en el área protésica con una intensidad superior a la del hígado o la médula ósea de raquis y pelvis. El diagnóstico final de infección, basado en los criterios de Fitzgerald, se estableció en 10 pacientes, siendo la gammagrafía positiva en 11. No se obtuvieron falsos negativos. Los valores de sensibilidad y especificidad fueron 100% y 95%, respectivamente, con un VPP del 91% y un VPN del 100%. Veinticinco pacientes contaban también con un TC previo a la gammagrafía, que en 9 de los casos fue positivo (4 FP). Los resultados de sensibilidad y especificidad del TC fueron del 62,5% y del 76%, con un VPP del 55,6% y un VPN del 81,3%. El diagnóstico de infección conllevó la exéresis del material protésico en 8 casos (todos ellos con confirmación microbiológica), mientras que los 2 restantes fueron tratados únicamente con antibioterapia debido a un alto riesgo quirúrgico. La GLM-SPECT/TC es una prueba de gran utilidad que presenta una alta precisión diagnóstica en la sospecha de infección de prótesis vasculares. Vascular graft infection is a rare complication with a high morbidity and mortality. Early diagnosis is essential to establish an adequate treatment. We assess the accuracy of 99mTc-WBC scintigraphy with SPECT/CT in the diagnosis of vascular graft infection. We retrospectively analyzed thirty 99mTc-WBC scintigraphies with SPECT/CT performed in thirty patients with suspicion of vascular prosthesis infection. Studies were considered positive for graft infection if the intensity of activity involving the graft was greater than the liver or bone marrow activity (spine and pelvis). Final diagnosis of infection was established in 10 patients, based on Fitzgerald criteria. Scintigraphy was positive in 11 patients. No false negatives were obtained. The values of sensitivity and specificity were 100% and 95%, respectively, with a PPV of 91% and a NPV of 100%. Twenty five patients had a CT performed prior to scintigraphy, in 9 cases the result was positive and in the remaining 16 was negative. CT sensitivity and specificity obtained in our study were 62.5% and 76% respectively, with a PPV of 55.6% and a NPV of 81.3%. Diagnosis of infection led to prosthesis exeresis in 8 cases (all of them had a positive microbiological study of the extracted material), while the remaining 2 patients were treated with antibiotic therapy alone due to high surgical risk. Our results suggest a high accuracy for 99mTc-WBC scintigraphy with SPECT/CT in the assessment of clinically suspected arterial graft infection. [ABSTRACT FROM AUTHOR]

Vascular graft infection (VGI) is a rare and severe complication after vascular surgery associated with significant morbidity and mortality, but the diagnosis is not always straightforward due to its variable and nonspecific clinical signs. Computed tomography (CT) scan is considered to be the diagnostic tool of choice for advanced VGI, but there is a high incidence of false-negative results, especially in low-grade infections. 18F-Fluorodeoxyglucose positron emission tomography with contrast-enhanced CT (18F-FDG PET-CT) imaging can serve as an effective alternative tool for assessment of suspected VGI and also provide accurate anatomic localization of the infective focus. Here, we describe three cases of VGI with various clinical presentations where the site of infection was diagnosed, confirmed, and documented with the help of 18F-FDG PET-CT imaging. [ABSTRACT FROM AUTHOR]

Background: Infection of vascular grafts is a life-threatening complication in cardiovascular surgical procedures. This experimental study tested the efficacy and possible harmful effects of daptomycin pre-treatment in vivo in prevention of vascular graft infection caused by Staphylococcus aureus.Methods: Polyethylene terephthalate (PET) patches (5 × 7 mm) were sewn on the infra-renal abdominal aorta of 32 New Zealand White rabbits. Before implantation, patches either were pre-treated for 15 min with daptomycin in one group (n = 13) or left untreated in the other group (n = 13) before contamination with 100 mcL bacterial solution (1 × 1010 colony-forming units [CFU] per mL). Six animals with uninfected patches without (n = 3) or with (n = 3) daptomycin pre-treatment served as controls. On postoperative day seven, all patches were explanted, washed with phosphate buffered saline, and sonicated to release viable adherent bacteria. The CFUs were quantified and aortic tissues were histologically examined. In addition, bacterial adherence on the patches was analyzed using scanning electron microscopy (SEM). Results: In the daptomycin pre-treatment group, significantly reduced numbers of CFUs on the patches were observed, compared with non-pre-treated patches (3.21 × 102 ± 1.02 × 103 mL-1 vs. 5.18 × 105 ± 1.05 × 106 mL-1; p < 0.001). Peri-vascular abscesses were visible in all rabbits with S. aureus infected patches, whereas no signs of inflammation were found in the daptomycin pre-treatment group or the control groups. Conclusions: Daptomycin showed excellent in vivo antibacterial activity against vascular graft infection caused by S. aureus, compared with non-pre-treated grafts, resulting in a significant reduction in bacterial infection and prevention of abscess formation. No harmful effects of the antibiotic pre-treatment could be observed. [ABSTRACT FROM AUTHOR]

Infective endocarditis (IE) is a life-threatening disease with stable prevalence despite prophylactic, diagnostic, and therapeutic advances. In parallel to the growing number of cardiac devices implanted, the number of patients developing IE on prosthetic valves and cardiac implanted electronic device (CIED) is increasing at a rapid pace. The diagnosis of IE is particularly challenging, and currently relies on the Duke-Li modified classification, which include clinical, microbiological, and imaging criteria. While echocardiography remains the first line imaging technique, especially in native valve endocarditis, the incremental value of two nuclear imaging techniques, 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG-PET/CT) and white blood cells single photon emission tomography with computed tomography (WBC-SPECT), has emerged for the management of prosthetic valve and CIED IE. In this review, we will summarize the procedures for image acquisition, discuss the role of 18F-FDG-PET/CT and WBC-SPECT imaging in different clinical situations of IE, and review the respective diagnostic performance of these nuclear imaging techniques and their integration into the diagnostic algorithm for patients with a suspicion of IE.