Daptomycin treatment in Gram-positive vascular graft infections

Long-term prognosis following vascular graft infection: a 10-year cohort study

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.

Treatment of Early Deep Wound Infections after Arterial Reconstructions: A Meta-Analysis and Survey

BACKGROUND

Peripheral vascular graft infections, a serious concern after open lower extremity interventions, are treated using multiple strategies. Yet, there is no consensus on the optimal treatment. This study summarizes the literature and compares aggregate effect sizes between graft preservation with antibiotic beads and total graft excision.

METHODS

Manuscripts published between 1972 and 2019 were systematically queried using Ovid Medline and PubMed. Studies were included if they described early (≤4 months of the index procedure) infection-related outcomes after extracavitary and infrainguinal arterial graft infections that were managed with antibiotic-loaded beads or total excisions. Outcomes assessed included the prevalence of graft preservation failure, reinfection, and major amputation. To examine current preferences on this subject, a voluntary, anonymous survey was administered to practicing members of the Society for Clinical Vascular Surgery.

RESULTS

Six graft preservation studies (n = 147 patients) were included in the meta-analysis, based on PRISMA guidelines. The meta-analytic pooled proportion of patients with: (1) graft preservation failure was 0.09 (95% CI: 0.00, 0.46, I² = 88.8%), (2) reinfection was 0.04 (95% CI: 0.00, 0.18, I² = 79.7%), and (3) major amputation was 0.00 (95% CI: 0.00, 0.04, I² = 0%). Five studies addressing total excisions were identified via the systematic review however, their combined sample size (n = 28 patients) impeded use of a meta-analysis. Ninety (19%) licensed surgeons participated in the survey. In a hemodynamically stable, nonseptic patient, 67% (60) of respondents routinely excise the graft, while 31% (28) prefer preservation.

CONCLUSIONS

Study design and patient characteristic-related heterogeneity limited our ability to generate robust, clinical evidence-level outcome estimates. A prospective study is necessary to definitively establish the efficacy of antibiotic beads in the treatment and preservation of vascular graft infections.

Successful Conservative Treatment of a Large Infected Saphenous Graft Aneurysm: Usefulness of PET/CT

We report a case of a 75-year-old man with a medical history of coronary artery bypass graft surgery and a recent graft angioplasty, who presented to our emergency department with fever. An 18F-fluorodeoxyglucose positron emission tomography demonstrated a saphenous graft infected aneurysm, which was successfully treated conservatively with antibiotic therapy. (Level of Difficulty: Beginner.).

Prevalence of mupirocin and chlorhexidine resistance among methicillin-resistant coagulase-negative staphylococci isolated during methicillin-resistant Staphylococcus aureus decolonization strategies

BACKGROUND

The widespread of methicillin-resistant Staphylococcus aureus (MRSA) antimicrobial decolonization in the clinical setting may lead to an increase in the prevalence of multiresistance to coagulase-negative staphylococci (CoNS) owing to their selection. This study aimed to investigate the impact of MRSA decolonization strategies, using mupirocin and chlorhexidine, on their CoNS susceptibility.

METHODS

A total of 312 CoNS isolates were collected before starting the decolonization protocols "baseline strains" (BLS) group, 330 isolates were collected after application of the targeted decolonization protocol "targeted decolonization strains" group, and 355 isolates were collected after application of the universal decolonization protocol "universal decolonization strains" group. Methicillin-resistant CoNS (MR-CoNS) were identified and tested for mupirocin and chlorhexidine susceptibilities. Heptaplex polymerase chain reaction assay was applied for simultaneous screening for chlorhexidine (CHX-R) and mupirocin resistance (Mu-R) genes.

RESULTS

Mu-R prevalence of MR-CoNS among the BLS group was considered moderate (9.1%); however, CHX-R in the BLS group was 5.8%, the rate of which significantly increased among the universal decolonization strains group.

DISCUSSION

Both MRSA decolonization strategies have an additional benefit in reducing the prevalence of MR-CoNS. The prevalence Mu-R rate didn't change significantly during either of the MRSA decolonization practices that may be due to the local nature of mupirocin application on the nasal mucosa only. In contrast CHX-R that was found to be significantly higher among the UDS group.

CONCLUSIONS

Our findings indicate that both MRSA decolonization strategies have an additional benefit in reducing the prevalence of MR-CoNS. Although the universal MRSA decolonization has superior efficacy in decolonization of CoNS, it may increase the risk of selecting CHX-R and Mu-R. In addition, other potential resistance genes should be studied.

Current and emerging pharmacotherapy for the treatment of infections following open-heart surgery

INTRODUCTION

Patients undergoing open-heart surgery may suffer from postoperative complications, including severe infections. Antimicrobials to treat infectious complications in this population should be selected thoughtfully, taking into account three different and fundamental issues: (i) the site of infection; (ii) the suspected or proven causative agent and its susceptibility pattern; and (iii) the risk of suboptimal pharmacokinetic characteristics and potential toxicity of the chosen drug/s.

AREAS COVERED

The present narrative review summarizes the current and future antimicrobial options for the treatment of infections developing after open-heart surgery.

EXPERT OPINION

The pharmacological treatment of infections developing in cardiac surgery patients poses peculiar challenges, including the need for an active empirical therapy for severe events such as bloodstream infections, deep sternal wound infections, or early-onset postoperative prosthetic endocarditis. In addition, the risk for multidrug-resistant pathogens should also be taken into account in endemic areas. A multidisciplinary evaluation on a patient-by-patient basis, deeply involving infectious diseases specialists and cardiothoracic surgeons, remains essential for appropriately balancing both short-term and long-term risks and benefits of any possible surgical reintervention in combination with adequate pharmacotherapy.

Complex treatment of vascular prostheses infections

Infections after vascular reconstructions are very rare; however, when they occur, they are associated with a high risk of morbidity. In order to obtain the best results possible, the treatment needs to be initiated as early as possible, from the very first signs of infection, and it needs to be carried out in centers specializing in vascular surgery. The aim of the present study was to assess the incidence of infections in a single university center.This retrospective analysis over a 2-year period is based on the medical reports of hospitalized patients who were diagnosed with infection following revascularization.From 2013 to 2014, a number of 151 open reconstructive surgical procedures were performed. 15 patients suffered from infection (10%) of the vascular reconstruction. Of these patients, 40% have had an aorto-bifemoral bypass, 53%-a femoro-popliteal bypass, and 7% (n = 1)-an axillo-femoral bypass. According to the Samson classification, the patients were categorized as follows: group 2: 6 cases, group 3: 2 cases, group 4: 4 cases, and group 5: 3 cases. The most frequent bacteria found were methicillin-resistant Staphylococcus aureus (MRSA) (n = 6, 40%), followed by S aureus (n = 5, 33%). The treatment options were: application of antibiotics alone without any invasive treatment in 3 patients, local irrigation and debridement in 6 patients, complete explantation of the prosthesis with a new extra-anatomic bypass in 6 cases, and partial excision of the prosthesis, which was replaced and covered with muscle flap, in 3 cases. The amputation rate in our study was 18%, which corresponds to the rates published in the literature.The treatment of infections in vascular surgery needs to be complex and adapted to each individual patient, because infections being in a permanent dynamic state. The treatment needs to be performed in specialized centers that have large experience in vascular surgery, in order for the patient to have the best chances of survival and protection from amputation.