RESUMEN
Enterococcus faecium, a common resident of the human gastrointestinal tract, is also a major pathogen. Prompt initiation of appropriate treatment is essential to improve patient outcome in disseminated E. faecium infections. However, ampicillin resistance is frequent in this species, rendering treatment difficult. We used a comprehensive approach, including clinical data review, whole-genome sequencing, and mass spectrometry, to characterize ampicillin-susceptible (EFM-S) and ampicillin-resistant (EFM-R) isolates. We included all patients with culture-confirmed E. faecium infection attending our hospital over a 16-month period. A comparison of 32 patients infected with EFM-S strains and 251 patients infected with EFM-R strains revealed that EFM-R isolates were strongly associated with a longer hospital stay, history of prior hospitalization, and the carriage of multidrug-resistant organisms. An analysis of the genomes of 26 EFM-S and 26 EFM-R isolates from paired patients revealed a population structure almost perfectly matching ampicillin susceptibility, with resistant isolates in clade A1, and susceptible isolates in clades A2 and B. The clade B and A2 isolates mostly came from digestive or biliary tract samples, whereas clade A1 isolates were mostly obtained from urine and blood. Finally, we built a custom database for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), which differentiated between clade B and clade A1/A2 strains with high-positive and high-negative predictive values (95.6% and 100%, respectively). This study provides important new insight into the clinical features and clades associated with EFM-S and EFM-R isolates. In combination with MALDI-TOF MS, these data could facilitate the rapid initiation of the most appropriate treatment.IMPORTANCEEnterococcus faecium is an important human pathogen in which the prevalence of ampicillin resistance is high. However, little is known about the clinical characteristics of patients infected with ampicillin-resistant and ampicillin-susceptible strains. Indeed, current knowledge is based on genus-wide studies of Enterococcus or studies of very small numbers of susceptible isolates, precluding robust conclusions. Our data highlight specific clinical features related to the epidemiology of EFM-S and EFM-R strains, such as length of hospital stay, history of prior hospitalization, carriage of multidrug-resistant organisms, and type of sample from which the isolate was obtained. The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with a custom-built database may make it possible to distinguish clade B isolates, which are typically susceptible to ampicillin, from clade A1/A2 isolates (A1 being typically resistant), thereby facilitating the management of these infections.
RESUMEN
BACKGROUND: During the COVID-19 pandemic, the suspension of relatives' visits was a common measure in healthcare facilities to prevent the spread of the virus among patients. This measure caused significant adverse consequences for hospitalized patients. Volunteers' intervention was an alternative but could also lead to cross transmission events. AIMS: in order to secure their intervention with patients, we implemented an infection control training to evaluate and to improve the knowledge of volunteers about infection control measures. METHOD: We performed a before-after study in a group of five tertiary referral teaching hospitals in the suburbs of Paris. A total of 226 volunteers from three groups (religious representatives, civilian volunteers and users' representatives) were included. Basic theoretical and practical knowledge about infection control, hand hygiene, and glove and mask use were evaluated just before and immediately after a three-hour training program. The contribution of the characteristics of the volunteers to the results was studied. FINDINGS: The initial conformity rate for theoretical and practical infection control measures ranged from 53% to 68%, depending on the participants' activity status and education level. Some critical shortcomings in hand hygiene as well as mask and glove wearing putatively endangered the patients and volunteers. Surprisingly, serious gaps were also identified among volunteers who experienced care activities. Regardless of their origin, the program significantly improved both their theoretical and practical knowledge (p<0.001). Real-life observance and long-term sustainability should be monitored. CONCLUSIONS: To become a secure alternative to relatives' visits, volunteers' interventions must be preceded by the assessment of their theoretical knowledge and practical skills in infection control. Additional study, including practice audit, must confirm the implementation of the acquired knowledge in the real-life.
Asunto(s)
COVID-19 , Pandemias , Humanos , Pandemias/prevención & control , COVID-19/epidemiología , COVID-19/prevención & control , Control de Infecciones , Voluntarios/educaciónRESUMEN
BACKGROUND: ß-lactams are the main antibiotics used against wild-type AmpC-producing Enterobacterales (wtAE). However, they may fail or select AmpC-overproducing mutants. Our aim was to assess factors associated with clinical failure of ß-lactams in the treatment of wtAE infection. METHODS: From September 2017 to December 2020, we prospectively included all consecutive patients treated by definitive ß-lactams therapy for wtAE infection in four university ICUs. Clinical failure was defined as inadequate response to antimicrobial therapy leading to death or to the switch for a broader-spectrum antibiotic. RESULTS: 177 patients were included and 29.4% progressed to clinical failure. E. cloacae was the most prevalent species (42.4%) and ventilator-associated pneumonia (VAP) was the most frequent wtAE infection (69.5%). Cefepime and cefotaxime were used as definitive antibiotic treatment in 42.9% and 27.7% of patients, respectively. Occurrence of AmpC-overproduction was documented in 5.6% of patients and was associated with clinical failure (p = 0.004). In multivariate analysis, VAP (p < 0.001, OR 11.58 [95% CI 3.11-43.02] and K. aerogenes (p = 0.030, OR 3.76 [95% CI 1.13-12.46]) were independently associated with clinical failure. Conversely, cefotaxime as definitive treatment was found inversely associated with the risk of clinical failure (p = 0.022, OR 0.25 [95% CI 0.08-0.82]). After inverse probability weighting, cefotaxime showed a 20% risk reduction of clinical failure (95% CI 5-35%, p = 0.007) whatever the location of infection, the SOFA score on the day of wtAE infection, or the bacterial species. CONCLUSIONS: Clinical failure in the treatment of wtAE infections is associated with the infection site and the causal microorganism. Additionally, cefotaxime use is probably protective against clinical failure in wtAE infection.
RESUMEN
Zoonotic species of Capnocytophaga genus belong to the oral microbiota of dogs and cats. They may be responsible for serious human infections, mainly after animal bites, with a high mortality rate. In France, only few cases have been reported and no multicenter study has been conducted. Our aim was to describe the French epidemiology of Capnocytophaga zoonosis. We conducted a multicenter (21 centers) retrospective non-interventional, observational study in France describing the epidemiology of Capnocytophaga zoonosis (C. canimorsus, C. cynodegmi, C. canis) over 10 years with regard to clinical and bacteriological data. From 2009 to 2018, 44 cases of Capnocytophaga zoonotic infections were described (C. canimorsus, n = 41; C. cynodegmi, n = 3). We observed an increase (2.5 times) in the number of cases over the study period (from the first to the last 5 years of the study). The most frequent clinical presentations were sepsis (n = 37), skin and soft tissue infections (n = 12), meningitis (n = 8), osteoarticular infections (n = 6), and endocarditis (n = 2). About one-third of patients with sepsis went into septic shock. Mortality rate was 11%. Mortality and meningitis rates were significantly higher for alcoholic patients (p = 0.044 and p = 0.006, respectively). Other comorbidities included smoking, splenectomy, diabetes mellitus, and immunosuppressive therapy are associated to zoonotic Capnocytophaga infection. Eighty-two percent of cases involved contact with dogs, mostly included bites (63%). Despite all isolates were susceptible to the amoxicillin-clavulanic acid combination, three of them were resistant to amoxicillin.
Asunto(s)
Alcoholismo , Mordeduras y Picaduras , Enfermedades de los Gatos , Enfermedades de los Perros , Infecciones por Bacterias Gramnegativas , Animales , Mordeduras y Picaduras/complicaciones , Mordeduras y Picaduras/epidemiología , Capnocytophaga , Enfermedades de los Gatos/microbiología , Gatos , Enfermedades de los Perros/microbiología , Perros , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Estudios Retrospectivos , Zoonosis/epidemiología , Zoonosis/microbiologíaRESUMEN
BACKGROUND: Linezolid-resistant enterococci (LRE) causing infections that are challenging to treat are rising, highlighting the need for reliable screening of LRE clinical isolates. OBJECTIVES: To evaluate the ability of the broth microdilution (BMD) method for LRE detection and to assess the performance of seven commercially available techniques for linezolid susceptibility testing. METHODS: A collection of 100 clinical isolates (80 Enterococcus faecium and 20 Enterococcus faecalis), including 20 optrA-positive isolates, 17 poxtA-positive isolates and 1 optrA/poxtA-positive E. faecium isolate, were studied. MICs were determined after 18 h [Day 1 (D1)] and 42 h [Day 2 (D2)] of incubation and interpreted following EUCAST and CLSI guidelines, which currently provide different interpretative breakpoints. Performance of commercial techniques was compared with BMD results. RESULTS: MIC50/D1 and MIC50/D2 were both 8 mg/L, while MIC90/D1 and MIC90/D2 were 16 and 32 mg/L, respectively. MICD1 values for poxtA-positive isolates were lower than those for optrA-positive isolates. Proportions of susceptible isolates at D1 and D2 were 48% and 41%, respectively, according to EUCAST breakpoints and 35% and 13%, respectively, according to CLSI criteria (the proportions of isolates categorized as intermediate following CLSI recommendations were 13% and 28% at D1 and D2, respectively). Percentage susceptibility assessed by the commercially available techniques was always higher. The four commercial methods allowing MIC determination provided an overall essential agreement of ≥90% at D1. Categorical agreement and error rates were generally improved at D2. CONCLUSIONS: Non-automated methods (Sensititre and UMIC) and, to a lesser extent, gradient strip Etest appear to show an acceptable correlation with the BMD reference method for the detection of isolates with low MICs of linezolid after prolonged incubation.
Asunto(s)
Enterococcus faecium , Infecciones por Bacterias Grampositivas , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Enterococcus faecalis , Humanos , Linezolid/farmacología , Pruebas de Sensibilidad MicrobianaRESUMEN
BACKGROUND: The stability of biochemical analytes has already been investigated, but results strongly differ depending on parameters, methodologies, and sample storage times. We investigated the stability for many biochemical parameters after different storage times of both whole blood and plasma, in order to define acceptable pre- and postcentrifugation delays in hospital laboratories. METHODS: Twenty-four analytes were measured (Modular® Roche analyzer) in plasma obtained from blood collected into lithium heparin gel tubes, after 2-6 hr of storage at room temperature either before (n = 28: stability in whole blood) or after (n = 21: stability in plasma) centrifugation. Variations in concentrations were expressed as mean bias from baseline, using the analytical change limit (ACL%) or the reference change value (RCV%) as acceptance limit. RESULTS: In tubes stored before centrifugation, mean plasma concentrations significantly decreased after 3 hr for phosphorus (-6.1% [95% CI: -7.4 to -4.7%]; ACL 4.62%) and lactate dehydrogenase (LDH; -5.7% [95% CI: -7.4 to -4.1%]; ACL 5.17%), and slightly decreased after 6 hr for potassium (-2.9% [95% CI: -5.3 to -0.5%]; ACL 4.13%). In plasma stored after centrifugation, mean concentrations decreased after 6 hr for bicarbonates (-19.7% [95% CI: -22.9 to -16.5%]; ACL 15.4%), and moderately increased after 4 hr for LDH (+6.0% [95% CI: +4.3 to +7.6%]; ACL 5.17%). Based on RCV, all the analytes can be considered stable up to 6 hr, whether before or after centrifugation. CONCLUSION: This study proposes acceptable delays for most biochemical tests on lithium heparin gel tubes arriving at the laboratory or needing to be reanalyzed.