Prognosis of prosthetic valve infective endocarditis due to Streptococcus spp., a retrospective multi-site study to assess the impact of antibiotic treatment duration

PURPOSE

The duration of antibiotic treatment for prosthetic valve endocarditis caused by Streptococcus spp. is largely based on clinical observations and expert opinion rather than empirical studies. Here we assess the impact of a shorter antibiotic duration.

OBJECTIVES

To assess the impact of antibiotic treatment duration for streptococcal prosthetic valve endocarditis on 12-month mortality as well as subsequent morbidity resulting in additional cardiac surgical interventions, and rates of relapse and reinfection.

METHODS

This retrospective multisite (N= 3) study examines two decades of data on patients with streptococcal prosthetic valve endocarditis receiving either 4 or 6 weeks of antibiotics. Overall mortality, relapse, and reinfection rates were also assessed for the entire available follow-up period.

RESULTS

The sample includes 121 patients (median age 72 years, IQR [53; 81]). The majority (74%, 89/121) received a ß-lactam antibiotic combined with aminoglycoside in 74% (89/121, median bi-therapy 5 days [1; 14]). Twenty-eight patients underwent surgery guided by ESC-guidelines (23%). The 12-month mortality rate was not significantly affected by antibiotic duration (4/40, 10% in the 4-week group vs 3/81, 3.7% in the 6-week group, p=0.34) or aminoglycoside usage (p=0.1). Similarly, there were no significant differences between the 2 treatment groups for secondary surgical procedures (7/40 vs 21/81, p=0.42), relapse or reinfection (1/40 vs 2/81 and 2/40 vs 5/81 respectively).

CONCLUSIONS

Our study found no increased adverse outcomes associated with a 4-week antibiotic duration compared to the recommended 6-week regimen. Further randomized trials are needed to ascertain the optimal duration of treatment for streptococcal endocarditis.

Pharmacokinetic Interaction between Rifampicin and Clindamycin in Staphylococcal Osteoarticular Infections

The oral combination of clindamycin and rifampicin is relevant for the treatment of staphylococcal osteoarticular infections (SOAI). However, rifampicin induces CYP3A4, suggesting a pharmacokinetic (PK) interaction with clindamycin with unknown PK/pharmacodynamic (PD) consequences.

OBJECTIVES

To quantify clindamycin PK/PD markers before and during rifampicin co-administration in OAI.

METHODS

Patients with SOAI were included (NCT02782078). After an initial intravenous antistaphylococcal treatment, oral therapy was started with clindamycin (600 or 750 mg tid), followed by the addition of rifampicin 36 hours after. Population PK analysis was performed using the SAEM algorithm. PKPD markers were compared with and without rifampicin co-administration, each patient being his own control.

RESULTS

In 19 patients, Clindamycin Median (min-max) through concentrations were 2.7 (0.3-8.9) and <0.05 (<0.05-0.3) mg/L, before and during rifampicin administration, respectively. Rifampicin co-administration increased clindamycin clearance by a factor 16 and reduced the AUC_0-8h /MIC by a factor 15 (p<0.005). We simulated clindamycin plasma concentration for 1000 individuals, without and with rifampicin. Against a susceptible S. aureus strain with a clindamycin MIC of 0.0625 mg/L, more than 80% of individuals would reach all the proposed PKPD targets without co-administration of rifampicin, even with a low clindamycin dose. For the same strain, when rifampicin was co-administered, the probability to reach clindamycin PKPD targets dropped to 1% to have a %fT_>MIC = 100% and to 6% to achieve an AUC_0-24/MIC > 60, even with high dose of clindamycin.

CONCLUSION

Rifampicin co-administration with clindamycin has high impact on clindamycin exposure and PKPD targets in SOAI, which could result in clinical failures, even for a fully susceptible strain.

Mortality in Escherichia coli bloodstream infections: antibiotic resistance still does not make it

BACKGROUND

Escherichia coli bloodstream infections (BSIs) account for high mortality rates (5%-30%). Determinants of death are unclear, especially since the emergence of ESBL producers.

OBJECTIVES

To determine the relative weight of host characteristics, bacterial virulence and antibiotic resistance in the outcome of patients suffering from E. coli BSI.

METHODS

All consecutive patients suffering from E. coli BSI in seven teaching hospitals around Paris were prospectively included for 10 months. E. coli isolates were sequenced using Illumina NextSeq technology to determine the phylogroup, ST/ST complex (STc), virulence and antimicrobial resistance gene content. Risk factors associated with death at discharge or Day 28 were determined.

RESULTS

Overall, 545 patients (mean ± SD age 68.5 ± 16.5 years; 52.5% male) were included. Mean Charlson comorbidity index (CCI) was 5.6 (± 3.1); 19.6% and 12.8% presented with sepsis and septic shock, respectively. Portals of entry were mainly urinary (51.9%), digestive (41.9%) and pulmonary (3.5%); 98/545 isolates (18%) were third-generation cephalosporin resistant (3GC-R), including 86 ESBL producers. In-hospital death (or at Day 28) was 52/545 (9.5%). Factors independently associated with death were a pulmonary portal of entry [adjusted OR (aOR) 6.54, 95% CI 2.23-19.2, P = 0.0006], the iha_17 virulence gene (aOR 4.41, 95% CI 1.23-15.74, P = 0.022), the STc88 (aOR 3.62, 95% CI 1.30-10.09, P = 0.014), healthcare-associated infections (aOR 1.98, 95% CI 1.04-3.76, P = 0.036) and high CCI (aOR 1.14, 95% CI 1.04-1.26, P = 0.006), but not ESBL/3GC-R.

CONCLUSIONS

Host factors, portal of entry and bacterial characteristics remain major determinants associated with mortality in E. coli BSIs. Despite a high prevalence of ESBL producers, antibiotic resistance did not impact mortality. (ClinicalTrials.gov identifier: NCT02890901.).

Microdiversity of Enterococcus faecalis isolates in cases of infective endocarditis: selection of non-synonymous mutations and large deletions is associated with phenotypic modifications

Context: Today, infective endocarditis (IE) caused by Enterococcus faecalis represents 10% of all IE and is marked by its difficult management and the frequency of relapses. Although the precise reasons for that remain to be elucidated, the evolution of the culprit strain under selective pressure through microdiversification could be, at least in part, involved. Material and methods: To further study the in situ genetic microdiversity and its possible phenotypic manifestations in E. faecalis IE, we sequenced and compared multiple isolates from the valves, blood culture and joint fluid of five patients who underwent valvular surgery. Growth rate and early biofilm production of selected isolates were also compared. Results: By sequencing a total of 58 E. faecalis genomes, we detected a considerable genomic microdiversity, not only among strains from different anatomical origins, but also between isolates from the same studied cardiac valves. Interestingly, deletions of thousands of bases including the well-known virulence factors ebpA/B/C, and srtC, as well as other large prophage sequences containing genes coding for proteins implicated in platelet binding (PlbA and PlbB) were evidenced. The study of mutations helped unveil common patterns in genes related to the cell cycle as well as central metabolism, suggesting an evolutionary convergence in these isolates. As expected, such modifications were associated with a significant impact on the in-vitro phenotypic heterogeneity, growth, and early biofilm production. Conclusion: Genome modifications associated with phenotypic variations may allow bacterial adaptation to both antibiotic and immune selective pressures, and thus promote relapses.

[The use of venous catheter : Which ones to choose, how to prevent their complications?]

Intravenous catheters are multiple and essential for daily practice. They are also responsible for high morbidity and mortality. Simple or echo-guided peripheral venous catheters, midlines, PICCline, tunneled or non-tunneled central venous catheters, and implantable venous access device are currently at our disposal. Thus, catheter selection, duration and indications for use, and prevention and treatment of complications vary according to the situation. The objective of this update is to provide the clinician with an overview of knowledge and rules of good practice on the use of catheters.

FRI0439 PET-CT IN THE ASSESSMENT OF OSTEOARTICULAR INFECTIONS ASSOCIATED WITH INFECTIVE ENDOCARDITIS

Background:

Five to eleven percent of infective endocarditis (IE) are associated with a musculoskeletal infection. Thanks to its good sensitivity, the use of PET-CT in this pathology makes it possible to confirm the diagnosis by seeking valvular hypermetabolism but also by mapping distant septic foci.

Objectives:

The main objective of our study was to assess the prevalence of osteoarticular fixation (OAF) with PET-CT, symptomatic or not, in patients with IE. The secondary objectives were to determine predictive factors for osteoarticular infections such as the type of valve damage (native or prosthetic) and germ.

Methods:

This study was carried out on the basis of a prospective cohort of patients admitted in the department of cardiology in Henri Mondor Hospital for IE suspicion between August 2015 and July 2019. Demographic, clinical, bacteriological, imaging and therapeutic data have been collected. Patients matching Duke’s modified criteria according to ESC 2015 (Duke + IE) and / or a cardiac fixation according to standard whole-body PET-CT were included in the analysis. All of the PET-CT scans were reviewed by a nuclear medicine specialist to confirm whether or not there was a heart condition and to look for septic-looking OAF.

Results:

From this cohort, we included 90 IE Duke + patients and 42 patients with cardiac PET-CT fixation (including 31 IE Duke +). In the IE Duke + group, we found OAF in 18 patients (20%), 39% of whom were asymptomatic. There were 9 spondylodiscitis (4 on the cervical level, 7 on the thoracic level, and 2 on the lumbar level), 5 glenohumeral arthritis, 2 coxofemoral arthritis, 1 sternoclavicular arthritis and 1 sacroiliac arthritis. The IE affected the aortic valve in 50% of the cases and the mitral valve in 22%. In other cases, the infection involved the internal automatic defibrillator (ICD) or the pacemaker. The valves were prosthetic in 73% of the cases. The bacterial ecology was mainly represented by Enterococcus faecalis (39%) then staphylococcus aureus (17%) against 14% and 13% respectively in the entire IE Duke + group. In the group with cardiac PET-CT fixation, OAF was found in 10 patients (40%), 70% of whom were asymptomatic. Among them, there were 5 spondylodiscitis (2 cervico- thoracic and 3 exclusively thoracic), 2 glenohumeral arthritis (20%), 2 coxofemoral arthritis and 1 sternoclavicular arthritis. The IE affected the aortic valve in 60% of the cases, mitral in 30% of the cases and it was an infection on ICD in 10% of the cases. The main germs found were Enterococcus faecalis (30% of cases) and Staphylococcus epidermidis (20% of cases).

Conclusion:

In patients with IE, PET-CT seems to be interesting in detection of osteoarticular infections, and consequently, could impact the diagnosis and the treatment modalities. In our cohort, 1 patient in 5 had an OAF and nearly 40% of them were asymptomatic. The overrepresentation of enterococcus is consistent with recent data in the literature

References:

[1]Dahl A, Iversen K, Tonder N, Hoest N, Arpi M, Dalsgaard M, et al. Prevalence of Infective Endocarditis in Enterococcus faecalis Bacteremia. J Am Coll Cardiol. 16 juill 2019;74(2):193‑201.

Disclosure of Interests:

Benjamin HUGUES: None declared, Bérivan EMSEN: None declared, Julien TERNACLE: None declared, Raphaëlle HUGUET: None declared, Antonio FIORE: None declared, Raphaëlle LEPEULE: None declared, Xavier Chevalier: None declared, Mukedaisi ABULIZI: None declared, Florent Eymard Consultant of: Regenlab

Molecular testing for respiratory pathogens in sickle cell disease adult patients presenting with febrile acute chest syndrome

BACKGROUND

Differentiating acute chest syndrome (ACS) from community-acquired pneumonia (CAP) is challenging in adults presenting with major sickle cell disease (SCD) (semiological similarity, rare microbiological documentation). We aimed to assess the usefulness of nucleic acid amplification test (NAAT) for respiratory pathogens, in combination with standard bacteriological investigations, in febrile ACS adult patients presenting with major SCD.

METHODS

We performed a prospective, monocentric, observational study of 61 SCD adults presenting with febrile ACS from February 2015 to April 2016. Systematic blood, urine, and respiratory specimens were collected, before antibiotic initiation, for culture, urinary antigen tests, serology, and NAAT for respiratory pathogens.

RESULTS

A pathogen was detected in 12 febrile ACS (19.7%): four viruses (6.6%) (Rhinovirus; Influenza A/B), seven bacteria (11.4%) (S. aureus, S. pneumoniae, K. pneumoniae, L. pneumophila, M. pneumoniae), one mixed infection (1.6%) (S. aureus and Influenza B). NAAT only detected L. pneumophila in one case (serogroup 2). Apart from a significantly shorter antibiotic therapy duration (6.1 vs. 7.8 days, P=0.045), no difference was observed between undocumented and microbiologically-documented febrile ACS.

CONCLUSION

Using NAAT for the detection of respiratory pathogens in adults presenting with SCD slightly improved the microbiological diagnostic of febrile ACS, although respiratory infections are not the main etiological factor.

[Influenzae and pneumococcal vaccination rate in an internal medicine ward]

INTRODUCTION

Vaccination against influenza virus and Streptococcus pneumoniae is a global health priority and authorities, on the basis of recent publications, have recently updated French recommendations. The aim of this study was to describe the influenzae and pneumococcal vaccination's rate in an internal medicine ward.

MATERIAL AND METHODS

All patients consecutively hospitalized during a 10 week-period in an internal medicine ward were included. The reasons for non-vaccination and the impact of an educational program for corrective measures were reported.

RESULTS

Overall, 198 consecutive patients were included; 93 (47%) were immunocompromised; 142 (71.2%) had an indication for pneumococcal vaccination and 171 (86.4%) for influenza vaccination but only 16.2% and 55% of them were vaccinated against these microorganisms, respectively. Prior pneumococcal vaccination was more frequently observed in immunocompromised patients than in non-immunocompromised patients (21.1 versus 6.4%; P=0.029), but no significant difference was observed for influenza vaccine. Corrective measures were initiated in 46 patients (39%), non-immunized against S. pneumoniae.

CONCLUSION

These results underline the very low prevalence of pneumococcal vaccination rate in at-risk hospitalized patients, as compared with influenza, despite recent recommendations.

Clearance of carbapenem-resistant Enterobacteriaceae vs vancomycin-resistant enterococci carriage after faecal microbiota transplant: a prospective comparative study

BACKGROUND

Carbapenem-resistant Enterobacteriaceae (CRE) and vancomycin-resistant enterococci (VRE) carriage are increasing worldwide. Faecal microbiota transplantation (FMT) appears to be an attractive option for decolonization. This study aimed to evaluate CRE vs VRE clearance by FMT among carriers.

METHODS

A multi-centre trial was undertaken on patients with CRE or VRE digestive tract colonization who received FMT between January 2015 and April 2017. Adult patients with CRE or VRE colonization, confirmed by three consecutive rectal swabs at weekly intervals, including one in the week prior to FMT, were included in the study. Patients with immunosuppression or concomitant antibiotic prescription at the time of FMT were excluded. Successful decolonization was determined by at least two consecutive negative rectal swabs [polymerase chain reaction (PCR) and culture] on Days 7, 14, 21 and 28, and monthly for three months following FMT.

RESULTS

Seventeen patients were included, with a median age of 73 years [interquartile range (IQR) 64.3-79.0]. Median duration of carriage of CRE or VRE before FMT was 62.5 days (IQR 57.0-77.5). One week after FMT, three of eight patients were free of CRE colonization and three of nine patients were free of VRE colonization. After three months, four of eight patients were free of CRE colonization and seven of eight patients were free of VRE colonization. Qualitative PCR results were concordant with culture. Six patients received antibiotics during follow-up, three in each group. No adverse events were reported.

CONCLUSION

CRE and VRE clearance rates were not significantly different in this study, possibly due to the small sample size, but a trend was observed. These data should be confirmed by larger cohorts and randomized trials.

Is faecal microbiota transplantation an option to eradicate highly drug-resistant enteric bacteria carriage?

Carbapenem-resistant Enterobacteriaceae (CRE) or vancomycin-resistant enterococci (VRE) carriage present a major public health challenge. Decolonization strategies are lacking. We aimed to evaluate the impact of faecal microbiota transplantation (FMT) on a cohort of patients with digestive tract colonization by CRE or VRE. Eight patients were included: six carrying CRE and two colonized by VRE. One month after FMT, two patients were free from CRE carriage, and another patient was free from VRE after three months. In our experience, this strategy is safe.

[Necrotizing fasciitis: results of a survey on management practices in French-speaking intensive care units]

OBJECTIVES

Necrotizing fasciitis (NF) are rare and severe soft tissue infections associated with a high mortality rate. In order to assess the management of NF in French-speaking intensive care units (ICUs), we conducted a survey endorsed by the French Society of Anesthesia and Intensive Care (SFAR).

STUDY DESIGN

Online self-administered survey.

METHODS

A link to an online survey was sent by email to 4620 anesthesiologists and/or intensivists and was available online from January to February 2014.

RESULTS

One hundred and seventy-five physicians (3.8%) who worked in 135 ICUs filled out the online survey. Among respondents, 42% reported having managed up to two patients with NF during the previous year; 59% and 72% of respondents reported not having a surgical and a medical specialist consultant, respectively. A delayed access to the operating room (OR) of more than 6hours was reported in 31% of cases and access to the OR was reported not to be routinely considered as a priority in 13% of cases. Only 17% of respondents reported that time to transfer to the OR was never a cause for delayed surgery. The main causes for delayed surgery were: delayed diagnosis (45%), delayed validation of surgical intervention (37%), and difficulty of access to the OR (8%). Finally, 83% of respondents estimated that creating dedicated multidisciplinary teams for managing NFs could lead to improving outcomes.

CONCLUSION

This survey illustrates the heterogeneous management of NF in French-speaking ICUs and points out several logistical aspects that should be improved to reduce the time to the first surgical debridement.

Clinical spectrum of urine cultures positive for ESBL-producing Escherichia coli in hospitalized patients and impact on antibiotic use

OBJECTIVE

We wanted to describe the clinical features associated with urinalysis positive for ESBL-producing Escherichia coli and their impact on antibiotic use.

METHODS

We performed a prospective observational study in 13 French hospitals of the Paris area for 3 consecutive months. We included all patients with urine cultures positive for ESBL-producing E. coli.

RESULTS

One hundred and seventeen of the 218 patients (54%) presented with asymptomatic bacteriuria, 31 (14%) with cystitis, and 70 (32%) with a parenchymal infection. Nineteen patients with asymptomatic bacteriuria (16%) received antibiotics. Forty-one with parenchymal infections (59%) received a carbapenem. A carbapenem alternative could have been used in every patient treated with a carbapenem, according to antibiotic susceptibility testing results.

CONCLUSIONS

Urinary tract infections accounted for 46% of E. coli ESBL positive urinalysis. Fifty percent of parenchymal infections were treated with a carbapenem.

Quinolones versus macrolides in the treatment of legionellosis: a systematic review and meta-analysis

BACKGROUND

Legionellosis is a life-threatening disease. The clinical superiority of quinolones or macrolides for treating patients with legionellosis has not been established.

METHODS

We performed a systematic review and meta-analysis of studies reporting data that allowed the comparison of quinolones versus macrolides in the treatment of proven legionellosis published from 1 January 1985 to 31 January 2013. We collected baseline aggregate patient characteristics. Studied outcomes included mortality, clinical cure, time to apyrexia, length of hospital stay and occurrence of complications in each treatment group. Treatment effect was assessed using a Mantel-Haenszel random effects model.

RESULTS

Among 1005 abstracts reviewed, 12 studies were selected (n=879 patients). No randomized controlled trial was performed directly comparing quinolone and macrolide efficacy in legionellosis. Mean age was 58.3 years, 27.7% were women and Fine score was ≥ 4 in 35.8%. Among 253 patients who received quinolone monotherapy, 10 died (4.0%). Among 211 patients who received macrolide monotherapy, 23 died (10.9%). The pooled OR of death for treatment with a quinolone versus a macrolide was 0.5 (95% CI 0.2-1.3, n=8 studies, 464 patients). Length of stay was significantly shorter in the quinolone monotherapy group. The difference was 3.0 days (95% CI 0.7-5.3, P=0.001, n=3 studies, 263 patients). Neither of two tests for heterogeneity was significant (I (2)=0% for both, P=1). Other studied outcomes were not significantly different among treatment groups.

CONCLUSIONS

Few clinical data on legionellosis treatment are available. This first meta-analysis showed a trend toward a lower mortality rate and a significant decrease in length of hospital stay among patients receiving quinolones. These results must be confirmed by a randomized controlled trial.