Assessment of three antibiotic combination regimens against Gram-negative bacteria causing neonatal sepsis in low- and middle-income countries.

Gram-negative bacteria (GNB) are a major cause of neonatal sepsis in low- and middle-income countries (LMICs). Although the World Health Organization (WHO) reports that over 80% of these sepsis deaths could be prevented through improved treatment, the efficacy of the currently recommended first- and second-line treatment regimens for this condition is increasingly affected by high rates of drug resistance. Here we assess three well known antibiotics, fosfomycin, flomoxef and amikacin, in combination as potential antibiotic treatment regimens by investigating the drug resistance and genetic profiles of commonly isolated GNB causing neonatal sepsis in LMICs. The five most prevalent bacterial isolates in the NeoOBS study (NCT03721302) are Klebsiella pneumoniae, Acinetobacter baumannii, E. coli, Serratia marcescens and Enterobacter cloacae complex. Among these isolates, high levels of ESBL and carbapenemase encoding genes are detected along with resistance to ampicillin, gentamicin and cefotaxime, the current WHO recommended empiric regimens. The three new combinations show excellent in vitro activity against ESBL-producing K. pneumoniae and E. coli isolates. Our data should further inform and support the clinical evaluation of these three antibiotic combinations for the treatment of neonatal sepsis in areas with high rates of multidrug-resistant Gram-negative bacteria.

The need to improve antimicrobial susceptibility testing capacity in Ugandan health facilities: insights from a surveillance primer.

BACKGROUND: Lab-based surveillance (LBS) of antimicrobial resistance (AMR) is not systematically implemented in Uganda. We aimed to identify the gaps in establishing regular LBS of AMR in Uganda. METHODS: This was a retrospective records review. It was done at Mulago Hospital (MH) Microbiology Lab (MHL). It analyzed lab records on bacteria and their antimicrobial susceptibility profiles (ASPs) over 6 months. Since MH is the national referral hospital, we hypothesized that (1) MHL is the best resourced and that any limitations seen here are amplified in labs at regional referral hospitals (RRHs) and health centers (HCs); (2) data from MHL on LBS mirrors that from labs at RRHs and HCs; (3) the state of records from MHL show lab performance and the presence or absence of standard operating procedures (SOPs), as would be the case at RRHs and HCs. RESULTS: The lab got 1760 samples over the six months. The most common sample was urine (659, 37.4%). From the 1760 samples, data on 478 bacterial isolates were available. Urine gave the most isolates (159, 33.3%). Most of the isolates were gram-negative (267, 55.9%). Escherichia coli (100, 37%) was the most common gram-negative (of the Enterobacteriaceae). Pseudomonas aeruginosa (17, 6%) was the most common gram-negative (of the non-Enterobacteriaceae). The gram-negative bacteria were highly resistant to ß-lactams. These were highly sensitive to carbapenems. The Staphylococcus aureus were highly resistant to ß-lactams. The gram-positive bacteria were highly sensitive to vancomycin. ASPs for all bacterial categories were incomplete. CONCLUSIONS: The findings from MHL suggest that there is a need to improve antimicrobial susceptibility testing capacity. They also suggest that the situation at RRHs and HCs around the country could be worse. So, there is a need to extend the political will, which already exists, into operational and implementation action.

Preparation and physicochemical assessment of bioactive films based on chitosan and starchy powder of white turmeric rhizomes (Curcuma Zedoaria) for green packaging applications.

In the current study, the bioactive films of chitosan/white turmeric (CH/WT) were prepared by employing solvent casting technique and analyzed their physicochemical and biological properties for active packaging applications. The successful inclusion of white turmeric into the chitosan matrix is confirmed by Fourier Transform Infrared Spectroscopy. Due to the presence of hydrogen bonding interaction, the active films exhibited good tensile properties, smooth surface morphology, miscibility, water resistance and UV barrier properties. The incorporation of white turmeric reduced the water vapour transmission rate and oxygen permeability (p < 0.05) in contrast with pristine film. The prepared blend films revealed soil degradation rate more than 60% within 15 days. Furthermore, the blend films exhibited lesser water solubility, moisture content and swelling index after addition of white turmeric to chitosan (p < 0.05). The prepared films revealed extensive antimicrobial activity against gram positive and gram negative bacteria. The antioxidant activity and total phenolic content were improved upon the incorporation of white turmeric. Moreover, the oil absorption rate of the blend films was decreased by 46% in comparison with pristine film. Overall, white turmeric incorporated chitosan films were employed as a green packaging material to extend the shelf life of the foodstuff.

Characterization of low-cost glycolipoprotein biosurfactant produced by Lactobacillus plantarum 60 FHE isolated from cheese samples using food wastes through response surface methodology and its potential as antimicrobial, antiviral, and anticancer activities.

Considering the need of new lactic acid bacteria (LAB) for the production of novel biosurfactant (BS) molecules, the current study brings out a new insight on the exploration of cheese samples for BS producers and process optimization for industrial applications. In view of this, Lactobacillus plantarum 60FHE, Lactobacillus paracasei 75FHE, and Lactobacillus paracasei 77FHE were selected as the most operative strains. The biosurfactants (BSs) described as glycolipoproteins via Fourier-transform infrared spectroscopy (FTIR) exhibited antimicrobial activity against the food-borne pathogens. L. plantarum 60FHE BS showed an anticancer activity against colon carcinoma cells and had a week antiviral activity against Hepatitis A virus. Furthermore, glycolipoprotein production was enhanced by 1.42-fold through the development of an optimized process using central composite design (CCD). Emulsifying activities were stable after 60-min incubation from 4 to 120 °C, at pH 2-12, and after the addition of NaCl (2-14%). Characterization by nuclear magnetic resonance spectroscopy (1H NMR) revealed that BS produced from strain 60FHE was glycolipoprotein. L. plantarum produced mixed BSs determined by Liquid Chromatography/Mass Spectrometry (LC-MS). Thus, indicating that BS was applied as a microbial food prevention and biomedical. Also, L. plantarum 60FHE BS was achieved with the use of statistical optimization on inexpensive food wastes.

Disparities in antimicrobial consumption and resistance within a country: the case of beta-lactams in Argentina / Disparidades en el consumo de antimicrobianos y la resistencia a estos dentro de un país: el caso de los betalactámicos en Argentina / Disparidades internas no consumo e na resistência aos antimicrobianos: o caso dos betalactâmicos na Argentina

ABSTRACT Objective. To describe bacterial resistance and antimicrobial consumption ratio at the subnational level in Argentina during 2018, considering beta-lactams group as a case-study. Methods. Antimicrobial consumption was expressed as defined daily doses (DDD)/1000 inhabitants. Resistance of Escherichia coli, Streptococcus pneumoniae, Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus to beta-lactams was recorded. Resistance/consumption ratio was estimated calculating "R" for each region of Argentina, and this data was compared with other countries. Results. The most widely consumed beta-lactams in Argentina were amoxicillin (3.64) for the penicillin sub-group, cephalexin (0.786) for first generation cephalosporins, cefuroxime (0.022) for second generation; cefixime (0.043) for third generation and cefepime (0.0001) for the fourth generation group. Comparison between beta-lactams consumption and bacterial resistance demonstrated great disparities between the six regions of the country. Conclusions. The case-study of Argentina shows that antimicrobial consumption and resistance of the most common pathogens differed among regions, reflecting different realities within the same country. Because this situation might also be occurring in other countries, this data should be taken into account to target local efforts towards better antimicrobial use, to improve antimicrobial stewardship programs and to propose more suitable sales strategies in order to prevent and control antimicrobial resistance.

RESUMEN Objetivo. Determinar la razón entre la resistencia bacteriana y el consumo de antimicrobianos a nivel subnacional en Argentina en el 2018, considerando el grupo de los betalactámicos como estudio de caso. Métodos. El consumo de antimicrobianos se expresó como una dosis diaria determinada (DDD) por 1000 habitantes. Se registró la resistencia de Escherichia coli, Streptococcus pneumoniae, Pseudomonas aeruginosa, Klebsiella pneumoniae y Staphylococcus aureus a los betalactámicos. Se determinó la razón entre la resistencia y el consumo calculando "R" para cada región de Argentina, y estos datos se compararon con los de otros países. Resultados. Los betalactámicos más consumidos en Argentina fueron la amoxicilina (3,64) para el subgrupo de la penicilina; la cefalexina (0,786) para las cefalosporinas de primera generación; la cefuroxima (0.022) para las de segunda generación; la cefixima (0.043) para las de tercera generación, y la cefepima (0.0001) para el grupo de la cuarta generación. La comparación entre el consumo de betalactámicos y la resistencia bacteriana demostró que había grandes disparidades entre las seis regiones del país. Conclusiones. El estudio de caso en Argentina indica que el consumo de antimicrobianos y la resistencia a los patógenos más comunes difería entre las regiones; esto demuestra que hay distintas realidades dentro del mismo país. Como esta situación también se puede dar en otros países, estos datos se deben tener en cuenta para definir las actividades locales destinadas a fomentar un mejor uso de los antimicrobianos, para mejorar los programas de manejo de los antimicrobianos y para proponer estrategias de venta más adecuadas con el fin de prevenir y controlar la resistencia a los antimicrobianos.

RESUMO Objetivo. Descrever a relação entre o consumo de antimicrobianos e a resistência bacteriana no nível subnacional na Argentina em 2018, considerando o grupo dos betalactâmicos no estudo de caso. Métodos. O consumo de antimicrobianos foi representado por doses diárias definidas (DDD) por 1.000 habitantes. Foi registrada a resistência de Escherichia coli, Streptococcus pneumoniae, Pseudomonas aeruginosa, Klebsiella pneumoniae e Staphylococcus aureus aos betalactâmicos. A relação entre consumo e resistência foi calculada com base no "R" para cada região do país e os dados da Argentina foram comparados aos de outros países. Resultados. Os betalactâmicos de maior consumo na Argentina foram amoxicilina (3,64) no grupo das penicilinas, cefalexina (0,786) no grupo das cefalosporinas de primeira geração, cefuroxima (0.022) no grupo das cefalosporinas de segunda geração, cefixima (0.043) no grupo das cefalosporinas de terceira geração e cefepima (0.0001) no grupo das cefalosporinas de quarta geração. Ao se comparar o consumo de betalactâmicos e a resistência bacteriana, observou-se grande disparidade entre as seis regiões do país. Conclusões. O estudo de caso revela diferenças no consumo de antimicrobianos e na resistência dos patógenos mais comuns entre as regiões da Argentina, refletindo realidades distintas dentro do mesmo país. Como esta mesma situação pode estar ocorrendo em outros países, estes achados devem servir para direcionar os esforços locais a uma melhor utilização dos antimicrobianos, aperfeiçoar os programas de gestão do uso destes medicamentos e propor estratégias de venda mais apropriadas, visando a prevenir e controlar a resistência aos antimicrobianos.

Assessment of the Biological Activity and Phenolic Composition of Ethanol Extracts of Pomegranate (Punica granatum L.) Peels.

Pomegranate (Punica granatum L.) is a rich source of constituents with confirmed strong biological activities. However, pomegranate peel, which encompasses approximately 30-40% of its weight, is treated as a biological waste. The aim of this paper was to evaluate the potential of pomegranate peel extracts and to propose its functional properties that can be used for development of functional products. Eight ethanol extracts of pomegranate peels (PPEs) were characterized by use of direct infusion quadrupole-time of flight (Q-TOF), and afterwards tested on their antioxidant, antibacterial and antiproliferative activities. Mass spectrometry analysis revealed that the most prevalent compounds in pomegranate peels were punicalagin, granatin and their derivatives. Analysed extracts had high total phenolic contents that ranged from 5766.44 to 10599.43 mg GAE/100 g, and strong antioxidant activity (7551.31-7875.42 and 100.25-176.60 µmol TE/100 g for DPPH and FRAP assays, respectively). The results of biological activity assays showed that all PPEs possessed antibacterial activity, and that S. aureus was the most sensitive specie with minimum inhibitory concentration and minimum bactericidal concentrations ranging from 0.8 to 6.4 mg/mL. Additionally, the analysis of antiproliferative activity revealed high potency of PPEs, as the IC50 values ranged from 0.132 mg/mL to 0.396 mg/mL. Multivariate analysis pointed out the most discriminative metabolites for antioxidant or antiproliferative activity. Overall, the pomegranate peel confirmed to be a highly valuable source of bioactive compounds that could be used to improve the food functional characteristics.

Clinical and economic impact of bacterial resistance: an approach to infection control and antimicrobial stewardship solutions.

PURPOSE OF REVIEW: The aim of this study was to describe the clinical and economic burden of bacterial antimicrobial resistance (AMR) and to provide an expert opinion on different approaches to fight it. RECENT FINDINGS: For several decades now, it has been known that AMR among human pathogens is related to high clinical and economic burden.Different strategies have been implemented to control the clinical and economic burden of AMR. Antimicrobial stewardship programmes (ASP), environmental cleaning and infection source control have been reported as the most effective interventions. There is a potential role for faecal microbiome transplant (FMT); however, long-term effectiveness and safety remain to be demonstrated. Another promising tool is to develop molecules to chelate or degrade residual antibiotics in the colon. Decolonization has demonstrated impact on methicillin-resistant Staphylococcus aureus (MRSA) infections, but there is limited evidence on the clinical impact and effectiveness of decolonization in MDR Gram-negative carriers. SUMMARY: A better assessment of AMR rates and the clinical and economic impact is needed. The epidemiology of AMR bacteria varies in different regions with MRSA, extended-spectrum beta-lactamase and carbapenamase-producing Enterobacterales being the most worrying. ASP and infection control have been increasingly demonstrated to impact on AMR rates. New approaches such as FMT and decolonization have still to demonstrate efficacy and safety.

Optimization of tigecycline dosage regimen for different infections in the patients with hepatic or renal impairment.

OBJECTIVE: The objective of this study was to investigate the cumulative fraction of response (CFR) of various tigecycline dosing regimens in patients with hepatic or renal impairment. METHODS: Monte Carlo simulations were performed using pharmacokinetic parameters and microbiological data to evaluate various tigecycline regimens in patients with hepatic or renal impairment. RESULTS: For HAP and cIAI, the regimen of 25 mg q12h achieved CFR values of >90% in Child-Pugh C patients against Gram-positive bacteria and partial Gram-negative bacteria (Escherichia coli and Klebsiella oxytoca). However, dose increases of tigecycline was mostly required for Enterobacter cloacae, Klebsiella pneumoniae and Acinetobacter baumanni. The conventional tigecycline regimen (50 mg q12h) was effective for HAP and cIAI caused by Gram-positive bacteria and Escherichia coli in patients with renal impairment. For HAP caused by Klebsiella pneumoniae and Enterobacter cloacae, patients with severe renal failure can use the standard dose regimen 50 mg q12h, and other patients need to increase the dose of tigecycline. However, when treating cSSSI caused by Acinetobacter baumannii, Enterobacter cloacae and Klebsiella pneumoniae, all tigecycline maintenance doses have a CFR <90%. CONCLUSIONS: It is necessary to optimize tigecycline dosage regimens in patients with hepatic or renal impairment in order to maximise clinical response and minimise the probability of exposure-related toxicity.

Quality Assessment, Functional Potentials, and Safety Evaluation of Stored Egyptian Honey as an Environmental Pollution Bioindicator.

Egyptian honeys are distinguished by their variety, properties, and therapeutic applications. The aim of the present study was to evaluate the quality and the functional and safety characteristics of Egyptian honey as a sensitive environmental bioindicator collected from 9 different locations in Egypt that were exposed to various air pollution sources, either stationary, mobile, or area sources, and stored for 6 mo at ambient temperature (22 ± 2 °C) compared with Codex Alimentarius international standards. Physicochemical properties, sugar profile via high performance liquid chromatography, functional potentials (antioxidant and antimicrobial), and safety parameters (microbiological quality, aflatoxins, and heavy metal pollutants) were assessed. The results revealed that honey obtained from Shabshir Hessa, El Gharbia Governorate (GSH-1), showed the best quality with the highest monosaccharide and phenolic and flavonoid content (73.07%, 363.07, and 15.33 mg/g, respectively) and clear of biotic and abiotic contaminants, reflecting good hygienic, environmental conditions and apiarian practices. The other 8 honey samples reflected inferior quality in physicochemical parameters either of low monosaccharide content (40.46-50.25%), high hydroxymethylfurfural (HMF) values as in Borg El-Arab Industrial Zone, Alexandria Governorate (BAI-9), and Nubaria Desert Road, Alexandria Governorate (NDR-4; 50.83 and 48.25 mg/kg), or of high acidity as in Agricultural Road, El Gharbia Governorate (GAR-3), and NDR-4 (74.72 and 68.47 mEq/kg) attributable to contaminated locations (fermentations) or thermal treatment (HMF). Furthermore, safety assessment revealed that coliform counts exceeded 2.5 log10 cfu/g in 6 samples-Chemicals Company, Kafr El Zayyat Governorate (KZC-2); GAR-3; NDR-4; Mansoura Fertilizer Talkha Company, Daqahlia Governorate (MFT-5); Gharbaniyat Cement Company, Beheira Governorate; and BAI-9-and the highest counts of yeast and molds in Abees Ceramic Company, Alexandria Governorate (3.72 log10 cfu/g), which was reflected in its total aflatoxins (679.83 µg/kg). Samples MFT-5; GAR-3; Kafr El-Sheikh Petroleum Company, Kafr El-Sheikh Governorate; and KZC-2 exceeded the lead permissible limit (0.75, 0.61, 0.57, and 0.51 mg/kg, respectively) as a result of inferior hygienic quality and the negative effects of environmental pollutants. The results ring alarm bells about how we should take substantial steps toward stringent standards for quality control practices of honey production operations. Environ Toxicol Chem 2020;39:1894-1907. © 2020 SETAC.

Needs assessment for novel Gram-negative antibiotics in US hospitals: a retrospective cohort study.

BACKGROUND: Evidence-based needs assessments for novel antibiotics against highly-resistant Gram-negative infections (GNIs) are scarce. We aimed to use real-world data from an electronic health record repository to identify treatment opportunities in US hospitals for GNIs resistant to all first-line drugs. METHODS: For this retrospective cohort study, population estimates with an unmet need for novel Gram-negative antibiotics were quantified using the Cerner Health Facts database (2009-15), aggregating episodes of infection in US hospitals with pathogens displaying difficult-to-treat resistance (DTR; resistance to carbapenems, other ß-lactams, and fluoroquinolones) and episodes involving empirical coverage with reserve drugs (colistin or polymyxin B and aminoglycosides). Episodes displaying extended-spectrum cephalosporin resistance (ECR) were also estimated. Episodes were multiplied by site-specific and fixed 14-day treatment durations for conservative and liberal days-of-therapy (DOT) estimates and stratified by site and taxon. Hospital type-specific DOT rates were reliability adjusted to account for random variation; cluster analyses quantified contribution from outbreaks. FINDINGS: Across 2 996 271 inpatient encounters and 134 hospitals, there were 1352 DTR-GNI episodes, 1765 episodes involving empirical therapy with colistin or polymyxin B, and 16 632 episodes involving aminoglycosides. Collectively, these yielded 39·0 (conservative estimate) to 138·2 (liberal estimate) DOT per 10 000 encounters for a novel DTR-GNI-targeted drug, whereas greater treatment opportunities were identified for ECR (six times greater) and ß-lactam susceptible GNIs (70 times greater). The most common DTR-GNI site and pathogen was lower respiratory (14·3 [43·3%] of 33 DOT per 10 000 encounters) and Pseudomonas aeruginosa (522 [38·1%] of 1371 episodes), whereas Enterobacteriaceae urinary-tract infections dominated the ECR or carbapenem-sparing niche (59·0% [5589 of 9535 episodes]) equating to 210·7 DOT per 10 000 encounters. DTR Stenotrophomonas maltophilia, Burkholderia spp, and Achromobacter spp represented less than 1 DOT per 10 000 encounters each. The estimated need for DTR-GNI-targeted antibiotics saw minor contributions by outbreaks and varied from 0·5 to 73·1 DOT per 10 000 encounters by hospital type. INTERPRETATION: Suspected or documented GNIs with no or suboptimal treatment options are relatively infrequent. Non-revenue-based strategies and innovative trial designs are probably essential to the development of antibiotics with improved effectiveness for these GNIs. FUNDING: Center for Drug Evaluation and Research, US Food and Drug Administration; Intramural Research Program, National Institutes of Health Clinical Center and the National Institute of Allergy and Infectious Diseases and the National Cancer Institute.

Effect of a "handshake" stewardship program versus a formulary restriction policy on High-End antibiotic use, expenditure, antibiotic resistance, and patient outcome.

This study reports the effect of implementing an antibiotic stewardship program (ASP) based on the "handshake" strategy for 2 years on multiple endpoints compared with that in a preceding period when an antimicrobial restriction policy was only applied in the absence of a complete program in a tertiary-care Lebanese hospital. The studied endpoints were broad-spectrum antibiotic consumption, antibiotic expenditure, nosocomial bacteremia incidence rate, and patient outcome.An interrupted time series analysis was undertaken to assess the changes in the trend (ΔT) and level (ΔL) of the aforementioned endpoints among adult inpatients before (October 2013 to September 2015) and after the introduction of the ASP (October 2016 to September 2018).After the implementation of the "handshake" ASP, marked changes were observed in the consumption of broad-spectrum antibiotics. The mean use density levels for imipenem and meropenem decreased by 13.72% (P = 0.017), coupled with a decreasing rate of prescription (ΔT = -24.83 defined daily dose [DDD]/1,000 patient days [PD]/month; P = 0.02). Tigecycline use significantly decreased in level by 69.19% (P < 0.0001) and in trend (ΔT = -25.63 DDD/1,000 PD/month; P < 0.0001). A reduction in the use of colistin was also documented but did not reach statistical significance (ΔL = -8.71%, P = 0.56; ΔT = -5.51 DDD/1,000 PD/month = -5.5; P = 0.67). Antibiotic costs decreased by 24.6% after ASP implementation (P < 0.0001), and there was a distinct change from an increasing rate to a decreasing rate of expenditure (ΔT = -12.19 US dollars/PD/month; P = 0.002). The incidence rate of nosocomial bacteremia caused by carbapenem-resistant gram-negative bacteria (CRGNB) decreased by 34.84% (P = 0.13) coupled with a decreasing trend (ΔT = -0.23 cases/1,000 PD/month, P = 0.08). Specifically, a noticeable reduction in the incidence rate of bacteremia due to carbapenem-resistant Acinetobacter baumannii was documented (ΔL = -54.34%, P = 0.01; ΔT = -0.24 cases/1000 PD/month, P = 0.01). Regarding patient outcome, all-cause mortality rates did not increase in level or in rate (ΔL = -3.55%, P = 0.59; ΔT = -0.29 deaths/1000 PD/month, P = 0.6). The length of stay and 7-day readmission rate remained stable between the two periods.In conclusion, the "handshake" ASP succeeded in controlling the prescription rates of antibiotics and in decreasing the nosocomial bacteremia rates caused by CRGNB without compromising patient outcome in our facility. It also had an economic effect in reducing antibiotic costs compared with the previous restriction policy on antimicrobial dispensing.

Rapid determination of carbapenem resistance by low-cost colorimetric methods: Propidium Iodide and alamar blue staining.

Carbapenems are a class of ß-lactam antibiotics with a broad antimicrobial activity spectrum. Owing to their sturdy structures resistant to most ß-lactamases, they have been regarded as one of the last-resort antibiotics for combating multidrugresistant bacterial infections. However, the emergence of carbapenem resistance increases predominantly in nosocomial pathogens. To prevent spread of carbapenem resistance in early stages, it is imperative to develop rapid diagnostic tests that will substantially reduce the time and cost in determining carbapenem resistance. Thus, we devised a staining-based diagnostic method applicable to three different Gram-negative pathogens of Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae, all with the high potential to develop carbapenem resistance. Regardless of the resistance mechanisms presented by bacterial species and strains, double staining with propidium iodide (PI) and alamar blue (AB) identified resistant bacteria with an average sensitivity of 95.35%, 7 h after imipenem treatments in 343 clinical isolates. Among the three species tested, A. baumannii showed the highest diagnostic sensitivity of 98.46%. The PI and ABmediated staining method could be a promising diagnostic method with high-throughput efficacy and low cost.

Clinical impact of rapid susceptibility testing on Mueller-Hinton Rapid-SIR directly from urine specimens.

Urinary tract infection diagnosis and management generally involves a 48-h microbiological delay to obtain the antibiotic susceptibility test (AST) results. In the context of multidrug resistance, reducing the time to obtain AST results is an essential factor, allowing for more timely appropriate treatment. We conducted a single-centre prospective study on urinary samples meeting two criteria: significant leukocyturia > 50/mm3 and exclusive presence of Gram-negative bacilli on direct examination. AST were performed by direct inoculation on Mueller-Hinton Rapid-SIR (MHR-SIR) agar. We evaluated the time to antibiotic adaptation by the antimicrobial stewardship team according to rapid AST results. Patients were subsequently excluded from the study if asymptomatic bacteria were confirmed, or in the absence of clinical data. Seventy patients were included. Mean age of patients was 68.8 years (± 21.3). Empirical antibiotic treatment were mainly based on third generation cephalosporins (n = 33), fluoroquinolones (n = 15), beta-lactamin/beta-lactamase inhibitors (n = 7), fosfomycin and nitrofurantoin (n = 5, each). The average time to obtain results was 7.2 h (± 1.6 h). Adaptation of therapy following MHR-SIR was performed for 29 patients (41%) with early switch to oral antibiotics, de-escalation or escalation in respectively 72.3%, 30%, and 11% of cases. Time saving of MHR-SIR compared with the standard technique was 42.6 (± 16.7) h. This study showed that rapid antibiotic susceptibility test results, using MHR-SIR method directly from urine, can be obtained 40 h earlier than conventional AST. The study also demonstrated significant clinical impact on the selection and reduction of the antibiotic therapy spectrum.

Attributable burden in patients with carbapenem-nonsusceptible gram-negative respiratory infections.

OBJECTIVE: We aimed to describe the clinical and economic burden attributable to carbapenem-nonsusceptible (C-NS) respiratory infections. METHODS: This retrospective matched cohort study assessed clinical and economic outcomes of adult patients (aged ≥18 years) who were admitted to one of 78 acute care hospitals in the United States with nonduplicate C-NS and carbapenem-susceptible (C-S) isolates from a respiratory source. A subset analysis of patients with principal diagnosis codes denoting bacterial pneumonia or other diagnoses was also conducted. Isolates were classified as community- or hospital-onset based on collection time. A generalized linear mixed model method was used to estimate the attributable burden for mortality, 30-day readmission, length of stay (LOS), cost, and net gain/loss (payment minus cost) using propensity score-matched C-NS versus C-S cohorts. RESULTS: For C-NS cases, mortality (25.7%), LOS (29.4 days), and costs ($81,574) were highest in the other principal diagnosis, hospital-onset subgroup; readmissions (19.4%) and net loss (-$9522) were greatest in the bacterial pneumonia, hospital-onset subgroup. Mortality and readmissions were not significantly higher for C-NS cases in any propensity score-matched subgroup. Significant C-NS-attributable burden was found for both other principal diagnosis subgroups for LOS (hospital-onset: 3.7 days, P = 0.006; community-onset: 1.5 days, P<0.001) and cost (hospital-onset: $12,777, P<0.01; community-onset: $2681, P<0.001). CONCLUSIONS: Increased LOS and cost burden were observed in propensity score-matched patients with C-NS compared with C-S respiratory infections; the C-NS-attributable burden was significant only for patients with other principal diagnoses.

A Decision Tree Using Patient Characteristics to Predict Resistance to Commonly Used Broad-Spectrum Antibiotics in Children With Gram-Negative Bloodstream Infections.

BACKGROUND: As rates of multidrug-resistant gram-negative infections rise, it is critical to recognize children at high risk of bloodstream infections with organisms resistant to commonly used empiric broad-spectrum antibiotics. The objective of the current study was to develop a user-friendly clinical decision aid to predict the risk of resistance to commonly prescribed broad-spectrum empiric antibiotics for children with gram-negative bloodstream infections. METHODS: This was a longitudinal retrospective cohort study of children with gram-negative bacteria cared for at a tertiary care pediatric hospital from June 2009 to June 2015. The primary outcome was a bloodstream infection due to bacteria resistant to broad-spectrum antibiotics (ie, cefepime, piperacillin-tazobactam, meropenem, or imipenem-cilastatin). Recursive partitioning was used to develop the decision tree. RESULTS: Of 689 episodes of gram-negative bloodstream infections included, 31% were resistant to broad-spectrum antibiotics. The decision tree stratified patients into high- or low-risk groups based on prior carbapenem treatment, a previous culture with a broad-spectrum antibiotic resistant gram-negative organism in the preceding 6 months, intestinal transplantation, age ≥3 years, and ≥7 prior episodes of gram-negative bloodstream infections. The sensitivity for classifying high-risk patients was 46%, and the specificity was 91%. CONCLUSION: A decision tree offers a novel approach to individualize patients' risk of gram-negative bloodstream infections resistant to broad-spectrum antibiotics, distinguishing children who may warrant even broader antibiotic therapy (eg, combination therapy, newer ß-lactam agents) from those for whom standard empiric antibiotic therapy is appropriate. The constructed tree needs to be validated more widely before incorporation into clinical practice.

Production of ammonia as a low-cost and long-distance antibiotic strategy by Streptomyces species.

Soil-inhabiting streptomycetes are nature's medicine makers, producing over half of all known antibiotics and many other bioactive natural products. However, these bacteria also produce many volatiles, molecules that disperse through the soil matrix and may impact other (micro)organisms from a distance. Here, we show that soil- and surface-grown streptomycetes have the ability to kill bacteria over long distances via air-borne antibiosis. Our research shows that streptomycetes do so by producing surprisingly high amounts of the low-cost volatile ammonia, dispersing over long distances to inhibit the growth of Gram-positive and Gram-negative bacteria. Glycine is required as precursor to produce ammonia, and inactivation of the glycine cleavage system nullified ammonia biosynthesis and concomitantly air-borne antibiosis. Reduced expression of the porin master regulator OmpR and its cognate kinase EnvZ is used as a resistance strategy by E. coli cells to survive ammonia-mediated antibiosis. Finally, ammonia was shown to enhance the activity of canonical antibiotics, suggesting that streptomycetes adopt a low-cost strategy to sensitize competitors for antibiosis from a distance.

Cefepime/sulbactam as an enhanced antimicrobial combination therapy for the treatment of MDR Gram-negative infections.

BACKGROUND: ß-Lactam (BL)/ß-lactamase inhibitor (BLI) combinations are widely used for the treatment of Gram-negative infections. Cefepime has not been widely studied in combination with BLIs. Sulbactam, with dual BL/BLI activity, has been partnered with very few BLs. We investigated the potential of cefepime/sulbactam as an unorthodox BL/BLI combination against MDR Gram-negative bacteria. METHODS: In vitro activity of cefepime/sulbactam (1:1, 1:2 and 2:1) was assessed against 157 strains. Monte Carlo simulation was used to predict the PTA with a number of simulated cefepime combination regimens, modelled across putative cefepime/sulbactam breakpoints (≤16/≤0.25 mg/L). RESULTS: Cefepime/sulbactam was more active (MIC50/MIC90 8/8-64/128 mg/L) compared with either drug alone (MIC50/MIC90 128 to >256 mg/L). Activity was enhanced when sulbactam was added at 1:1 or 1:2 (P<0.05). Reduction in MIC was most notable against Acinetobacter baumannii and Enterobacterales (MIC 8/8-32/64 mg/L). Pharmacokinetic/pharmacodynamic modelling highlighted that up to 48% of all isolates and 73% of carbapenem-resistant A. baumannii with a cefepime/sulbactam MIC of ≤16/≤8 mg/L may be treatable with a high-dose, fixed-ratio (1:1 or 1:2) combination of cefepime/sulbactam. CONCLUSIONS: Cefepime/sulbactam (1:1 or 1:2) displays enhanced in vitro activity versus MDR Gram-negative pathogens. It could be a potential alternative to existing BL/BLI combinations for isolates with a cefepime/sulbactam MIC of 16/8 mg/L either as a definitive treatment or as a carbapenem-sparing option.

Difficult-to-Treat Antibiotic-Resistant Gram-Negative Pathogens in the Intensive Care Unit: Epidemiology, Outcomes, and Treatment.

Antibiotic resistance among gram-negative pathogens is a world-wide problem that poses a constant threat to patients in the intensive care unit and a therapeutic challenge for the intensivist. Furthermore, the substantial economic burden and increased mortality associated with infections due to highly resistant gram-negative pathogens exacerbate these challenges. Understanding the mechanisms, epidemiology, and risk factors for these infections is paramount to the successful control of outbreaks and for guiding therapy which often entails use of antibiotics with suboptimal efficacy and/or toxicity profiles. In this review we will discuss the global epidemiology, burden, risk factors, and treatment of highly resistant gram-negative infections as they apply to the intensive care population.

Direct medical costs of urinary tract infections by Gram-negative bacilli resistant to beta-lactams in a tertiary care hospital in Medellín, Colombia / Costos médicos directos de las infecciones del tracto urinario por bacilos Gram negativos resistentes a betalactámicos en un hospital de alta complejidad de Medellín, Colombia

Introduction: Urinary tract infections are very frequent in the hospital environment and given the emergence of antimicrobial resistance, they have made care processes more complex and have placed additional pressure on available healthcare resources. Objective: To describe and compare excess direct medical costs of urinary tract infections due to Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa resistant to beta-lactams. Materials and methods: A cohort study was conducted in a third level hospital in Medellín, Colombia, from October, 2014, to September, 2015. It included patients with urinary tract infections caused by beta-lactam-susceptible bacteria, third and fourth generation cephalosporin-resistant, as well as carbapenem-resistant. Costs were analyzed from the perspective of the health system. Clinical-epidemiological information was obtained from medical records and the costs were calculated using standard tariff manuals. Excess costs were estimated with multivariate analyses. Results: We included 141 patients: 55 (39%) were sensitive to beta-lactams, 54 (38.3%) were resistant to cephalosporins and 32 (22.7%) to carbapenems. The excess total adjusted costs of patients with urinary tract infections due to cephalosporin- and carbapenem-resistant bacteria were US$ 193 (95% confidence interval (CI): US$ -347-734) and US$ 633 (95% CI: US$ -50-1316), respectively, compared to the group of patients with beta-lactam sensitive urinary tract infections. The differences were mainly found in the use of broad-spectrum antibiotics such as meropenem, colistin, and fosfomycin. Conclusion: Our results show a substantial increase in the direct medical costs of patients with urinary tract infections caused by beta-lactam-resistant Gram-negative bacilli (cephalosporins and carbapenems). This situation is of particular concern in endemic countries such as Colombia, where the high frequencies of urinary tract infections and the resistance to beta-lactam antibiotics can generate a greater economic impact on the health sector.

Introducción. Las infecciones del tracto urinario son muy frecuentes en el ámbito hospitalario. Debido a la aparición de la resistencia antimicrobiana, la complejidad de los procesos de atención ha aumentado y, con ello, la demanda de recursos. Objetivo. Describir y comparar el exceso de los costos médicos directos de las infecciones del tracto urinario por Klebsiella pneumoniae, Enterobacter cloacae y Pseudomonas aeruginosa resistentes a betalactámicos. Materiales y métodos. Se llevó a cabo un estudio de cohorte en una institución de tercer nivel de Medellín, Colombia, entre octubre del 2014 y septiembre del 2015. Se incluyeron los pacientes con infección urinaria, unos por bacterias sensibles a los antibióticos betalactámicos, y otros por bacterias resistentes a las cefalosporinas de tercera y cuarta generación y a los antibióticos carbapenémicos. Los costos se analizaron desde la perspectiva del sistema de salud. La información clínico-epidemiológica se obtuvo de las historias clínicas y los costos se calcularon utilizando los manuales tarifarios estándar. El exceso de costos se estimó mediante análisis multivariados. Resultados. Se incluyeron 141 pacientes con infección urinaria: 55 (39 %) por bacterias sensibles a los betalactámicos, 54 (38,3 %) por bacterias resistentes a las cefalosporinas y 32 (22,7 %) por bacterias resistentes a los carbapenémicos. El exceso de costos totales ajustado de los 86 pacientes con infecciones del tracto urinario por bacterias resistentes a las cefalosporinas y a los carbapenémicos, fue de USD$ 193 (IC95% -347 a 734) y USD$ 633 (IC95% -50 a 1.316), respectivamente comparados con el grupo de 55 pacientes por bacterias sensibles a los betalactámicos. Las diferencias se presentaron principalmente en el uso de antibióticos de amplio espectro, como el meropenem, la colistina y la fosfomicina. Conclusión. Los resultados evidenciaron un incremento sustancial de los costos médicos directos de los pacientes con infecciones del tracto urinario por bacterias resistentes a las cefalosporinas o a los carbapenémicos. Esta situación genera especial preocupación en los países endémicos como Colombia, donde la alta frecuencia de infecciones del tracto urinario y de resistencia a los betalactámicos puede causar un mayor impacto económico en el sector de la salud.

Fight Against Antimicrobial Resistance: We Always Need New Antibacterials but for Right Bacteria.

Antimicrobial resistance in bacteria is frightening, especially resistance in Gram-negative Bacteria (GNB). In 2017, the World Health Organization (WHO) published a list of 12 bacteria that represent a threat to human health, and among these, a majority of GNB. Antibiotic resistance is a complex and relatively old phenomenon that is the consequence of several factors. The first factor is the vertiginous drop in research and development of new antibacterials. In fact, many companies simply stop this R&D activity. The finding is simple: there are enough antibiotics to treat the different types of infection that clinicians face. The second factor is the appearance and spread of resistant or even multidrug-resistant bacteria. For a long time, this situation remained rather confidential, almost anecdotal. It was not until the end of the 1980s that awareness emerged. It was the time of Vancomycin-Resistance Enterococci (VRE), and the threat of Vancomycin-Resistant MRSA (Methicillin-Resistant Staphylococcus aureus). After this, there has been renewed interest but only in anti-Gram positive antibacterials. Today, the threat is GNB, and we have no new molecules with innovative mechanism of action to fight effectively against these bugs. However, the war against antimicrobial resistance is not lost. We must continue the fight, which requires a better knowledge of the mechanisms of action of anti-infectious agents and concomitantly the mechanisms of resistance of infectious agents.