Infections caused by carbapenem-resistant Enterobacteriaceae are a public health problem associated with higher mortality rates, longer hospitalization and increased healthcare costs. We carried out ...a study to describe the characteristics of patients with carbapenemase-producing Enterobacteriaceae (CPE) and non-CPE bloodstream infection (BSI) from Latin American hospitals and to determine the clinical impact in terms of mortality and antibiotic therapy.
Between July 2013 and November 2014, we conducted a multicenter observational study in 11 hospitals from 7 Latin American countries (Argentina, Colombia, Ecuador, Guatemala, Mexico, Peru, Venezuela). Patients with BSI caused by Enterobacteriaceae were included and classified either as CPE or non-CPE based on detection of blaKPC, blaVIM, blaIMP, blaNDM and blaOXA-48 by polymerase chain reaction. Enrolled subjects were followed until discharge or death. Demographic, microbiological and clinical characteristics were collected from medical records. Both descriptive and inferential statistics were used to analyze the information.
A total of 255 patients with Enterobacteriaceae BSI were included; CPE were identified in 53 of them. In vitro non-susceptibility to all screened antibiotics was higher in the patients with CPE BSI, remaining colistin, tigecycline and amikacin as the most active drugs. Combination therapy was significantly more frequent in the CPE BSI group (p < 0.001). The most common regimen was carbapenem + colistin or polymyxin B. The overall mortality was 37% (94/255). Overall and attributable mortality were significantly higher in patients with CPE BSI (p < 0.001); however, we found that patients with CPE BSI who received combination therapy and those who received monotherapy had similar mortality. After multivariate adjustment, CPE BSI (adjusted odds ratio aOR 4; 95% confidence interval CI 1.7-9.5; p = 0.002) and critical illness (aOR 6.5; 95% CI 3.1-13.7; p < 0.001) were independently associated with in-hospital mortality.
This study provides valuable data on the clinical characteristics and mortality risk factors in patients with CPE BSI. We determined that CPE infection is an independent mortality predictor and thus Latin American hospitals should perform campaigns on prevention and control of CPE BSI.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Antimicrobial stewardship programs (ASPs) have become a fundamental pillar in optimizing antimicrobial usage, improving patient care, and reducing antimicrobial resistance (AMR). Herein we evaluated ...the impact of an ASP on antimicrobial consumption and AMR in Colombia.
We designed a retrospective observational study and measured trends in antibiotic consumption and AMR before and after the implementation of an ASP using interrupted time series analysis over a 4-year period (24 months before and 24 months after ASP implementation).
ASPs were implemented according to the available resources in each of the institutions. Before ASP implementation, there was a trend toward an increase in the antibiotic consumption of all measured antimicrobials selected. Afterward, an overall decrease in antibiotic consumption was observed. The use of ertapenem and meropenem decreased in hospital wards, while a decrease in the use of ceftriaxone, cefepime, piperacillin/tazobactam, meropenem, and vancomycin was observed in intensive care units. After ASP implementation, the trend toward an increase of oxacillin-resistant Staphylococcus aureus, ceftriaxone-resistant Escherichia coli, and meropenem-resistant Pseudomonas aeruginosa was reversed.
In our study, we showed that ASPs are a key strategy in tackling the emerging threat of AMR and have a positive impact on antibiotic consumption and resistance.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objectives
Identify molecular mechanisms responsible for the
in vitro
non-susceptibility to ceftolozane/tazobactam (TOL) in a group of 158 clinical isolates of
Pseudomonas aeruginosa
from five Latin ...American countries collected before the introduction of TOL into the clinical practice.
Methods
Clinical isolates of
P. aeruginosa
(
n
= 504) were collected between January 2016 and October 2017 from 20 hospitals located in Argentina, Brazil, Chile, Colombia, and Mexico. Minimum inhibitory concentrations (MICs) to TOL were determined by standard broth microdilution and interpreted according to CLSI breakpoints. Initially, production of carbapenemases in TOL non-susceptible isolates was assessed by Rapidec® followed by qPCR to detect
bla
KPC
,
bla
NDM-1
,
bla
VIM
, and
bla
IMP
. Illumina® WGS was performed for isolates in which non-susceptibility to TOL was not mediated by carbapenemases.
Results
A total of 158 (31.3%) isolates were non-susceptible to TOL. In 74 (46.8%) of these isolates, non-susceptibility to TOL was explained by the production of at least one carbapenemase. WGS revealed that some isolates carried ESBLs, mutated
bla
PDC
and
ampD
, associated with decreased susceptibility to TOL.
Conclusion
Substitutions found in PDC and carbapenemase production were the most common presumed mechanisms of resistance to TOL detected in this study. This study shows that epidemiological surveillance is warranted to monitor the emergence of novel mechanisms of resistance to TOL that might compromise its clinical utility.
•High fosfomycin susceptibility rates (>90%) among MDR Enterobacteriaceae and P. aeruginosa clinical isolates.•Differences between CLSI and EUCAST recommendations for fosfomycin susceptibility ...testing are discussed.•Both disk diffusion and broth microdilution tests overestimate resistance.
This study aimed to evaluate the susceptibility of clinical isolates of Enterobacterales and Pseudomonas aeruginosa to fosfomycin and to determine the concordance of disk diffusion (DD) and broth microdilution (BMD) with agar dilution (AD) for fosfomycin susceptibility testing.
The activity of fosfomycin against 225 clinical isolates of Escherichia coli (n = 64), Klebsiella pneumoniae (n = 68), Enterobacter spp. (n = 28) and P. aeruginosa (n = 65) was tested by AD, DD and BMD. For DD, results were recorded considering and not considering colonies growing within the inhibition halo as recommended by the CLSI and EUCAST, respectively. Escherichia coli breakpoints were used for all Enterobacterales. Results were reported as categorical agreement (CA), major error (ME; false-resistant), very major error (VME; false-susceptible) and minor error (any other discrepancies).
Fosfomycin susceptibility of all tested species was >90% by AD. Following CLSI guidelines, DD was the only method reaching ≥90% CA with AD for E. coli and K. pneumoniae, albeit yielding 6% ME. Neither DD nor BMD achieved acceptable CA percentages for Enterobacter spp. Following EUCAST guidelines, none of the methods had CA ≥ 90%. For Enterobacterales, the best performance of DD is achieved when read as indicated by EUCAST but interpreted according the CLSI breakpoints (>97% CA; 0% VME; ≤2% ME). For P. aeruginosa, BMD yielded the best results (89% CA; 0% VME; 11% ME).
Neither DD or BMD provide accurate results owing to unacceptable ME and VME percentages even when performed as intended by the guidelines.
The carbapenem inactivation method (CIM) is a cost-effective assay for detecting carbapenemases. However, its interpretation is unclear for Pseudomonas spp. We evaluate its accuracy when meropenem is ...changed to imipenem.
We analyzed 266 P. aeruginosa isolates. The CIM method consists of: resuspend bacterial colonies (a full 10μL loop) in 400μL water, in which a 10μg disk of meropenem/imipenem is immersed. After 2h of incubation (35°C), remove the disk, place it onto a Mueller-Hinton agar plate previously inoculated with Escherichia coli (ATCC 25922), and incubate at 35 ̊C between 18-24 h. Interpretation criteria (mm of inhibition zone): ≤19mm, positive; ≥25mm negative; 20–24mm, undetermined.
Imipenem improves the sensitivity and specificity of CIM when compared to meropenem (99.4% and 98.9%, vs. 91.9% and 94.7%, respectively).
The accuracy of CIM for carbapenemase detection in P. aeruginosa is increased with the use of imipenem.
El método de inactivación del carbapenem (CIM, por sus siglas en inglés) se utiliza para detectar carbapenemasas, pero su interpretación no está clara para Pseudomonas spp. Se evaluó la precisión del método utilizando imipenem en lugar de meropenem.
Se estudiaron 266 aislados de P. aeruginosa. El CIM consiste en: suspender colonias bacterianas (un asa de 10μl) en 400μl de agua en los que se sumerge un disco de 10μg de meropenem/imipenem. Tras 2h de incubación (35°C) se saca el disco y es transferido a agar Mueller-Hinton, previamente inoculado con Escherichia coli (ATCC 25922) e incubado a 35°C entre 18-24h. Criterios de interpretación (mm halo de inhibición): ≤19mm positivo; ≥25mm negativo y 20-24mm indeterminado.
Imipenem mejora la sensibilidad y especificidad del CIM frente a meropenem (99,4 y 98,9% vs. 91,9 y 94,7%, respectivamente).
La precisión del CIM para la detección de carbapenemasas en P. aeruginosa mejora al utilizar imipenem.
Introducción. La evolución de la resistencia bacteriana constituye una amenaza para la salud pública mundial. Los sistemas de vigilancia epidemiológica han integrado técnicas de biología molecular ...para mejorar las estrategias de control. Objetivo. Describir los perfiles moleculares y fenotípicos de los bacilos Gram negativos en unidades de cuidados intensivos de 23 hospitales de Colombia entre 2009 y 2012. Materiales y métodos. Se diseñó un estudio descriptivo en 23 hospitales del Grupo para el Estudio de la Resistencia Nosocomial (sic.) en Colombia. Se analizaron 38.048 aislamientos usando WHONET durante el periodo descrito. Se describieron perfiles de resistencia para Escherichia coli , Klebsiella pneumoniae , Pseudomonas aeruginosa y Acinetobacter baumannii. En 1.248 cepas se realizó reacción en cadena de la polimerasa (PCR) para detectar las carbapenemasas clínicamente más relevantes. Resultados. Escherichia coli fue el microorganismo más frecuente (promedio=14,8 %); la frecuencia de aislamientos de K. pneumoniae aumentó de 11 % en 2009 a 15 % en 2012 (p<0,001). La tendencia de los perfiles de multirresistencia aumentó en todas las especies estudiadas. De los aislamientos de K. pneumoniae evaluados, 68,4 % fue positivo para KPC ( Klebsiella pneumoniae Carbapenemase ), mientras que la VIM ( Verona Integron-encoded Metallo-betalactamase ) en P. aeruginosa se observó en 46,5 %. Conclusiones. Se observó un incremento en la tendencia de los microorganismos hacia la multirresistencia y una amplia distribución de las carbapenemasas. La articulación de la biología molecular con los sistemas de vigilancia permitió integrar el análisis del fenotipo con los mecanismos de resistencia involucrados en las bacterias estudiadas. Este análisis permitirá la elaboración de guías para el uso adecuado de antimicrobianos y contribuirá a la contención de estas bacterias multirresistentes en Colombia.
Recent studies suggest that sustained use of generic antibiotics may be associated with clinical failure and emergence of antibacterial resistance. The present study was designed to determine the ...clinical outcome between the use of generic meropenem (GM) and brand-name meropenem (BNM). Additionally, this study evaluated the economic impact of GM and BNM to determine if the former represents a cost-effective alternative to the latter.
Patients treated between January 2011 and May 2014 received GM while patients treated between June 2014 and March 2017 received BNM. Mortality was compared between groups. Total infection cost was defined by the cost of antimicrobial consumption, length of stay, and laboratory and imaging exams until infection resolution.
A total of 168 patients were included; survival rate for the 68 patients treated with GM was 38% compared to 59% in the patients treated with BNM. Multivariate analysis showed that the variables most strongly-associated with mortality were cardiovascular disease (OR 18.18, 95% CI 1.25–262.3, p = 0.033) and treatment with generic meropenem (OR 18.45, 95% CI 1.45–232.32, p = 0.024). On the other hand, total infection cost did not show a significant difference between groups (BNM $10,771 vs. GM $11,343; p = 0.91).
The present study suggests that patients treated with GM have a risk of death 18 times higher compared to those treated with BNM. Furthermore, economic analysis shows that GM is not more cost effective than BNM.
More studies measuring clinical outcomes are needed to confirm the clinical equivalence of brand-name versus generic antibiotics, not only for meropenem but also for other molecules.
The global success of multidrug-resistant Acinetobacter baumannii has been associated with the dissemination of a high-risk clone designated clonal complex (CC) 92
(Bartual scheme)/CC2
(Pasteur ...scheme), which is the most frequent genetic lineage in European, Asian, and North American carbapenem-resistant Acinetobacter isolates. In these isolates, carbapenem resistance is mainly mediated by β-lactamases encoded by bla
, bla
, bla
, and/or bla
genes. In this study, we characterized the population genetics of 121 carbapenem-resistant A. baumannii complex isolates recovered from 14 hospitals in seven cities in Colombia (2008-2010). Multiplex PCR was used to detect bla
, bla
, bla
, and bla
genes. Molecular typing was performed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). PCR showed that 118 (97.5%) of the isolates were positive for both bla
and bla
genes, and three other isolates were only positive for bla
. PFGE identified 18 different pulsotypes, while MLST identified 11 different sequence types (STs), seven of which had not been previously described in Acinetobacter. None of the STs found in this study was associated with CC92
/CC2
. The most widespread STs in our isolates belonged to ST636 and their single-locus variants ST121/ST124/ST634 (CC636
) followed by STs belonging to CC110
. Our observations suggest a wide distribution of diverse A. baumannii complex clones containing bla
in Colombian hospitals (especially CC636
and CC110
) that differ from the high-risk clones commonly found in other regions of the world, indicating a distinct molecular epidemiology of carbapenem-resistant Acinetobacter spp. in Colombia.
Background: Ceftolozane/tazobactam (C/T) is a combination of an antipseudomonal oxyiminoaminothiazolyl cephalosporin with potent in vitro activity against Pseudomonas aeruginosa and tazobactam, a ...known β-lactamase inhibitor. The aim of this study was to evaluate the activity of C/T against clinical isolates of P. aeruginosa and Enterobacterales collected from five Latin American countries between 2016 and 2017, before its clinical use in Latin America, and to compare it with the activity of other available broad-spectrum antimicrobial agents. Methods: a total of 2760 clinical isolates (508 P. aeruginosa and 2252 Enterobacterales) were consecutively collected from 20 hospitals and susceptibility to C/T and comparator agents was tested and interpreted following the current guidelines. Results: according to the CLSI breakpoints, 68.1% (346/508) of P. aeruginosa and 83.9% (1889/2252) of Enterobacterales isolates were susceptible to C/T. Overall, C/T demonstrated higher in vitro activity than currently available cephalosporins, piperacillin/tazobactam and carbapenems when tested against P. aeruginosa, and its performance in vitro was comparable to fosfomycin. When tested against Enterobacterales, it showed higher activity than cephalosporins and piperacillin/tazobactam, and similar activity to ertapenem. Conclusions: these results show that C/T is an active β-lactam agent against clinical isolates of P. aeruginosa and Enterobacterales.