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Introduction. Resistance to carbapenems represents a public health across the world. Screening for carbapenem resistance can be done starting from the antibiogram, but confirmatory methods are usually performed in reference centers. Methods for rapid identification of carbapenemase activity are required to empower laboratories to detect carbapenemases and raise signals for infectious disease physicians, antibiotic stewardship teams and hospital hygiene specialists. Materials and methods. Eppendorf tubes containing Klebsiella pneumoniae strains with carbapenemase activity (KPC-1, NDM-1, OXA-48) and others with no carbapenemase activity (K. pneumoniae ATCC 700603 and E. coli ATCC 25922), as well as positive and negative controls were incubated at 37 °C with varying concentrations of Meropenem. After incubation, samples were spun down until a pellet formed and the supernatant was used to challenge an exponentially growing E. coli culture. This second culture was followed with nephelometric measurements every half hour. Experiments were carried out in three technical replicates. The statistical analysis was done with R (version 3.3.3) and graphs generated in RStudio (version 1.0.136) with ggplot2 (version 2.1.0). Mann Whitney U Test with the assumption of independent samples was used to analyse the results. Results. The doses of Meropenem were chosen after dose ranging experiments and multiple incubation times (from 30 minutes to two hours) were tested in order to evaluate the robustness of the method. In the cases where the antibiotic was first incubated with strains that had carbapenemase activity, the growth of Escherichia coli ATCC 25 922 was non-hindered, matching that of controls. In the absence of carbapenemase activity and in the case of negative controls, the growth indicator strain was inhibited. Statistically significant differences were identified for 0.3, as well as a 0.5 McFarland index as early as 1.5 hours total work time. Conclusions. The discovery of carbapenem resistance has direct clinical, as well as epidemiological implications. Among the mechanisms implicated in resistance to carbapenems, the presence of a carbapenemase is one of the most worrying from an epidemiological standpoint. This new tool we describe herein can be performed in all clinical microbiology laboratories, with no extra expense (as opposed to CarbaNP and BlueCarba tests). [ABSTRACT FROM AUTHOR]

Carbapenems are last resort antibiotics used in infections caused by multidrug-resistant bacteria. Carbapenem-resistant Enterobacteriaceae infections are an increasingly global threat, especially because carbapenemase production is more frequent than other resistance mechanisms and is encoded by genes located on transferable genetic structures. The production of classes A (KPC), B (IMP, VIM, NDM) and D (OXA-48 and its variants) of carbapenemases has important clinical consequences and is a constant pool of resistance. This review tries to show the diversity of carbapenemases and to underline their importance. [ABSTRACT FROM AUTHOR]

Introduction: Respiratory tract infections (upper and lower) represent one of the most frequent problems that lead to community medical visits, according to official data. In the hospital environment, the treatment of infections requiring inpatient care needs to be carried out in accordance with institutional guidelines, adapted to local antimicrobial resistance patterns. Information about the spectrum of bacterial resistance is often absent. Materials and methods: A retrospective study of the antibiogram registry of the Bacteriology Laboratory of the “Marius Nasta” National Institute of Pneumophtysiology (NIP) in Bucharest. The most frequent microorganisms isolated from pulmonary samples of adult inpatients in 2015 were analyzed. Results: The resistance of Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus spp., Klebsiella spp., Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa was analyzed. We reported the total number of isolates, the number of analyzed isolates (the ones that come from patients who meet the inclusion criteria) and the absolute and proportion figures for resistant, intermediate and sensitive strains. Resistance is described for each of the microorganisms. Special cases of resistance (like methicillin resistant staphylococci and carbapenem resistant enterobacteriaceae; CRE) have been highlighted because of the need to monitor their evolution over time as well as the importance to approach them systemically (prevention and treatment). Discussions: The spectrum of resistance varies according to the ward where the patient was cared for. The isolates from the medical wards were, in general, less resistant than those from the ICU/surgery wards. Conclusions: Due to the high variability in the spectrum of bacterial resistance of the most frequent isolates from medical practice, heightened attention is required in choosing the appropriate empiric antibiotic coverage and adherence to sampling and diagnostic procedures. The present article helps to better characterize the epidemiology of infections and antibiotic resistance in the “Marius Nasta” Institute; it identifies the difficulties faced in gathering and analyzing the data and can be considered as a reference point to improve medical practice policies with regards to the use of antibiotics. [ABSTRACT FROM AUTHOR]

The production of carbapenemases is one of the most important mechanisms that lead to carbapenem resistance. At the same time, the carbapenemases present on extracromosomial genetic material (plasmids) are transmitted between various bacteria. Although the genes Klebsiella, Enterobacter and Escherichia are most commonly involved in infections, the identification of carbapenemases in other genes may be very important for controlling infections. In this article, we will review a recent study published in the Morbidity and Mortality Weekly Report, which evaluated the production of carbapenemases in enterobacteria belonging to genes less commonly involved in clinical practice. All strains of enterobacteria transmitted to the Center for Disease Control (CDC) in Atlanta and the Public Health Laboratory of the Minnesota Health Department (MDH) from 1 January 2014 to 30 September 2017 were screened for the identification of five carbapenemases (KPC, NDM, OXA-48, IMP, and VIM). Among these, the results for the genera Klebsiella, Enterobacter and Escherichia were excluded. CDC received 1039 EPC-RC isolates during the study, of which 63 (6.1%) of the infrequently identified genera. Over the same period, 149 (12%) of the 1241 CREs were producing carbapenemases. Although in small numbers, isolates from more infrequent genera of enterobacteria that produce carbapenemases may be an important reservoir for dissemination to other bacteria. Additionally, we will add suggestions for current, cost-effective methodological solutions that can improve the knowledge of carbapenemase production in our country. [ABSTRACT FROM AUTHOR]

Globally, more than 50% of HIV infected people are women. HIV infection in women has its particularities, especially because of pregnancy and because of the adverse effects of antiretroviral therapy. Heterosexual contact is the most frequent way of HIV transmission in women. Some gynecological infections like vaginal candidiasis seem to be more persistent and more severe as compared to uninfected female patients. Also, HIV infected women have a higher risk for cervical dysplasia and cancer as compared to uninfected women. The risk of mother-to-child transmission of the virus has dropped significantly in the last decades because of the implementation of routine HIV screening testing in pregnancy, counseling regarding prevention and the large access to antiretroviral treatment. Today, because of the diversity of the therapeutic options and using good prophylactic measures, HIV infected women can have a normal life. [ABSTRACT FROM AUTHOR]

Acute bronchitis is a frequent clinical entity, characterized by an acute, which is sometimes associated with upper respiratory tract infection. The m ajority of acute com m unity acquired bronchitis is caused by viral infections. Although in the absence of comorbidities and complications the prognosis is excellent, bronchitis is a frequent cause of antibiotic prescription. The present article wishes to review the clinical and functional aspects pertaining to the disease, as well as the microbiology and treatment of uncomplicated bronchitis in the immunocompetent adult. The role of influenza vaccination is highlighted as a preventive measure. We hope that the article will draw an alarm signal regarding antibiotic prescription in the frequent condition and that it will help in limiting the phenomenon of antibiotic resistance [ABSTRACT FROM AUTHOR]

Introduction: In a previously published article, we have presented aspects regarding the physiology of microcalorimetrie bacterial growth in a liquid broth medium, in the absence of continuous agitation. Metronidazole is an antibacterial and antiparasitic agent used for the treatment of infections with anaerobic microorganisms as well as some parasitic infestations. The present work presents the growth of an aerobic, facultative anaerobic reference Escherichia coli strain (ATCC 25922), in the presence of metronidazole. Materials and Methods: The inoculum studied was a 0.1 McFarland unit suspension, which was then, diluted 1/100. A Setaram microDSC 7 Evo differential scanning microcalorimeter was used to register bacterial growth patterns. A constant volume of bacterial inoculum was pipeted into Hastelloy cells. Different concentrations of antibiotic were prepared to the same volume with the use of Physiologic Saline (PS) and were added to the bacterial culture, before incubation, leading to a constant volume of air in the headspace of the cell. Hermetic seal was realized with the use of a silicon o-ring. The working efficient volume of the cell was 0.94 ml. The total working bacteria-drug suspension was 0.70 ml. Results: The modifications brought about by metronidazole at the level of the Escherichia coli growth curve appeared in a dose-dependent manner. The addition of metronidazole did not modify the total heat produced by the bacterial growth process (as objectified by the area under curve). Discussion: Through the comparison of the microcalorimetrie results obtained by other authors and the comparative analysis of the bacterial growth curves, shows the fact that metronidazole has a particular effect, one which is not seen in the interaction with other antibiotic classes. Conclusions: Metronidazole seems to have a characteristic effect on the microcalorimetrie growth curve of a bacterial population that is developing in liquid media, in oxygen restrictive conditions. [ABSTRACT FROM AUTHOR]

Introduction: Bacterial growth in liquid growth medium, in the absence of cell agitation subjects the microorganisms to different oxygenation regimes, due to limitation in oxygen diffusion rate. When oxygen itself is limited, microorganisms will grow in anaerobic and microaerophilic conditions. The goal of this paper is to present the differences in bacterial growth associated with variations in residual oxygen inside the microcalorimetric cells. Materials and Methods: The bacterial strain chosen for this investigation was Escherichia coli (ATCC 25922). The studied inoculum represents a hundred fold dilution of a 0.1 McFarland units suspension, subjected to stationary growth, lacking homogenization, at 37°C in a differential scanning Setaram microDSC III microcalorimeter. To explore the metabolism in the context of limited oxygen supply, the bacterial suspension was cultivated in Hastelloy cells, hermetically sealed with silicon o-rings, provided by the manufacturer. The total efficient volume of the cell is 0.94ml. The volume of residual air (and implicitly, of oxygen) in the headspace of the cell was adjusted by addition to the bacterial suspension of Physiological Saline (PS). Results: The comparison the growth curves obtained by recording the growth of 0.6 ml of suspension with those of 0.3 ml and 0.3 ml with addition of 0.3 ml PS shows the differences in bacterial metabolism when oxygen and nutritive medium are in different volumes. Reducing of the bacterial suspension by half resulted in decrease in the intensity of the first peak, while at the same time leading to increase in the second peak. The addition of PS maintained roughly the same first peak intensity, while bringing the second peak intensity to its original level. Discussions: Published studies of microbial microcalorimetry do not present data of base processes that lead to generation of the microcalorimetric curve. This first experimental analysis of bacterial growth helps in understanding the processes of growth under limited oxygen conditions. We propose that differences in remaining oxygen inside the microcalorimetric cells would, in part, be responsible for the variability seen in the specialty literature. [ABSTRACT FROM AUTHOR]

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Copyright of Infectio.ro is the property of MEDICHUB MEDIA, S.R.L. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)