Antibiotic Resistance Rates Research Articles

Pasteurella multocida and Mannheimia haemolytica; virulence factors, diseases, and notably increasing antibiotic resistance rate among their isolates: a comprehensive review

TThe current review on Pasteurella multocida and Mannheimia haemolytica tried to shed light on these two organisms due to their medical and economic importance as well as to their elevating antibiotic resistance rate among the isolates from animals basically cattle, sheep, and goats. In this comprehensive review, we screened both old and recently published works that are available electronically on authorized scientific sites. Here we provide the latest data on those organisms their structure, suitable growth conditions, virulence factors, pathogenesis, their associated diseases, and their distribution along with antibiotic resistance emergence and the possibility of more new emergences of resistant isolates among species of both organisms. Lastly, we reviewed all the old and modern methods for diagnosis, controlling, and preventing the occurrence of diseases caused by these organisms besides studying and reviewing the effective ways to manage antibiotic resistance issues. Our review concluded that more specific research is needed to shed light on phenotype and genotype differences among those organisms, some issues should be subjected to intensive investigations and research focus such as emerging and re-emerging infectious diseases caused by these organisms and antigenic variants between agents. Evaluation of innate and adaptive immunity after infections or vaccinations is important for producing more specific drugs or vaccines in the future.

Epidemiological, Virulence, and Antibiotic Resistance Analysis of Klebsiella pneumoniae, a Major Source of Threat to Livestock and Poultry in Some Regions of Xinjiang, China.

Klebsiella pneumoniae (K. pneumoniae) is recognized as a zoonotic pathogen with an increasing threat to livestock and poultry. However, research on K. pneumoniae of animal origin remains limited. To address the gap, a comprehensive investigation was carried out by collecting a total of 311 samples from the farms of four animal species (dairy cow, chicken, sheep, and pig) in selected areas of Xinjiang, China. Isolates were identified by khe gene amplification and 16S rRNA gene sequencing. Genotyping of K. pneumonia isolates was performed using wzi typing and multilocus sequence typing (MLST). PCR was employed to identify virulence and resistance genes. An antibiotic susceptibility test was conducted using the Kirby-Bauer method. The findings revealed an isolation of 62 K. pneumoniae strains, with an average isolation rate of 19.94%, with the highest proportion originating from cattle sources (33.33%). Over 85.00% of these isolates harbored six virulence genes (wabG, uge, fimH, markD, entB, and ureA); while more than 75.00% of isolates possessed four resistance genes (blaTEM, blaSHV, oqxA, and gyrA). All isolates exhibited complete resistance to ampicillin and demonstrated substantial resistance to sulfisoxazole, amoxicillin/clavulanic acid, and enrofloxacin, with an antibiotic resistance rate of more than 50%. Furthermore, 48.39% (30/62) of isolates were classified as multidrug-resistant (MDR) strains, with a significantly higher isolation rate observed in the swine farms (66.67%) compared to other farms. Genetic characterization revealed the classification of the 62 isolates into 30 distinct wzi allele types or 35 different sequence types (STs). Notably, we identified K. pneumoniae strains of dairy and swine origin belonging to the same ST42 and wzi33-KL64 types, as well as strains of dairy and chicken origin belonging to the same wzi31-KL31-K31 type. These findings emphasize the widespread occurrence of drug-resistant K. pneumoniae across diverse animal sources in Xinjiang, underscoring the high prevalence of multidrug resistance. Additionally, our results suggest the potential for animal-to-animal transmission of K. pneumoniae and there was a correlation between virulence genes and antibiotic resistance genes. Moreover, the current study provides valuable data on the prevalence, antibiotic resistance, and genetic diversity of K. pneumoniae originating from diverse animal sources in Xinjiang, China.

Current and emerging strategies to curb antibiotic-resistant urinary tract infections.

Rising rates of antibiotic resistance in uropathogenic bacteria compromise patient outcomes and prolong hospital stays. Consequently, new strategies are needed to prevent and control the spread of antibiotic resistance in uropathogenic bacteria. Over the past two decades, sizeable clinical efforts and research advances have changed urinary tract infection (UTI) treatment and prevention strategies to conserve antibiotic use. The emergence of antimicrobial stewardship, policies from national societies, and the development of new antimicrobials have shaped modern UTI practices. Future UTI management practices could be driven by the evolution of antimicrobial stewardship, improved and readily available diagnostics, and an improved understanding of how the microbiome affects UTI. Forthcoming UTI treatment and prevention strategies could employ novel bactericidal compounds, combinations of new and classic antimicrobials that enhance bacterial killing, medications that prevent bacterial attachment to uroepithelial cells, repurposing drugs, and vaccines to curtail the rising rates of antibiotic resistance in uropathogenic bacteria and improve outcomes in people with UTI.

Reducing Improper and Missed Peri-Procedure Antibiotics Prescriptions in a Regional Oncology Centre.

Background In the realm of oncology care, patients undergoing invasive procedures are particularly vulnerable to infections due to their compromised immune systems. Antibiotics play a pivotal role in preventing such infections. However, inappropriate or missed administration of peri-procedure antibiotics poses a significant risk in the form of treatment complications, contributing to antibiotic resistanceand increased healthcare costs. Methods The study was a two-cycle, closed-loop quality improvement project utilizing both retrospective and prospective data analysis of peri-procedure antibiotics prescription in a regional oncology centre. Two audit cycles were carried out in total; the first cycle was carried out in November 2023 where six-week data were collected retrospectively. As a result, formal and informal teaching sessions about the importance of correct peri-procedure antibiotics and the availability of complete institutional peri-procedure antibiotics guidelines in clinical areas were ensured. The second cycle was carried out prospectively for two weeks in January 2024. Patients were included if they underwent selected procedures performed by interventional radiology or gastroenterology while the patients operated on by the general surgeons and any day case procedures were excluded. Results We identified a total of 82 interventional procedures during the first cycle that fulfilled the inclusion criteria. Six out of 82 patients (7.3%) did not receive the correct peri-procedural antibiotics as per hospital antibiotics guidelines. A prospective two-week data after implementing the change revealed that 25 patients had documented interventional procedures done during this period using electronic patient records. Out of 25 patients, only one patient (4%) did not receive the peri-procedural antibiotics as per guidelines. We were able to demonstrate increased adherence to the peri-procedural guidelines (from 93% to 96%) during the two cycles. However, this change was not statistically significant (p = 0.50). Conclusion By educating and engaging healthcare professionals in adhering to evidence-based guidelines and best practices, we have observed notable, although statistically significant improvement in peri-procedure antibiotics prescription practices. Continued educational efforts and reinforcement strategies will be vital in further improvements over time. By providing ongoing support and resources, healthcare providers can be empowered to consistently make informed decisions regarding peri-procedure antibiotic administration. This commitment to maintaining high standards of antibiotic prescribing practices is expected to result in improved patient outcomes, including reduced rates of surgical site infections and antibiotic resistance. It is imperative to recognize the critical role that accurate peri-procedure antibiotic prescriptions play in patient safety and overall healthcare quality. By fostering a culture of continuous improvement and adherence to established guidelines, we can ensure that patients receive optimal care while minimizing the risks associated with antibiotic overuse or misuse.

Treatment failure is a key factor in the development of Helicobacter pylori resistance.

Helicobacter pylori eradication failure influences its antibiotic resistance. This study aimed to evaluate the effect of previous treatment failures on it, including the changes in the antibiotic resistance rates, minimal inhibitory concentration (MIC) distributions, and resistance patterns. This single-center retrospective study included 860 primary isolates and 247 secondary isolates. Antibiotic susceptibility testing was performed for amoxicillin, metronidazole, clarithromycin, levofloxacin, furazolidone, tetracycline, and rifampicin. The demographic data and detailed regimens were collected. The primary resistance rates to amoxicillin, metronidazole, clarithromycin, levofloxacin, tetracycline, rifampin, and furazolidone were 5.93%, 83.84%, 28.82%, 26.28%, 0.35%, 1.16%, and 0%, while secondary were 25.10%, 92.31%, 79.76%, 63.16%, 1.06%, 3.19%, and 0%, respectively. The resistance rates to amoxicillin, metronidazole, clarithromycin, and levofloxacin increased significantly with the number of treatment failures accumulated, and showed a linear trend. The proportion of primary and secondary multidrug-resistant (MDR) isolates were 17.79% and 63.16%, respectively. The MIC values of amoxicillin, clarithromycin, and levofloxacin were elevated significantly with medication courses increased. The prevalence of amoxicillin, clarithromycin, levofloxacin, and metronidazole resistance would increase rapidly following first-line treatment failure, as well as the MIC values of them. Clinicians should pay great attention to the first-line treatment to cure H. pylori infection successfully.

Evaluation of the presence of integrons, sul and smqnr genes and the prevalence of antibiotic resistance in Stenotrophomonas maltophilia clinical isolates

ObjectivesThe objective of this investigation was to examine the mechanisms associated with antibiotic resistance in Stenotrophomonas maltophilia clinical isolates retrieved from hospitalized patients undergoing open heart surgery in a Heart Center located in Tehran, Iran. Materials and methodsThis investigation encompassed a cross-sectional study of 60 S. maltophilia isolates, which were procured from diverse clinical specimens. Primary identification of the isolates was conducted through conventional microbiologic methods and subsequently verified by means of PCR primers. The E-test was utilized to establish the minimum inhibitory concentrations (MICs). PCR was then employed to ascertain the antibiotic resistance genes (sul1, sul2, Smqnr and intl1 - intl3). ResultsIn this study, a total of sixty clinical isolates of S. maltophilia were collected, with the majority of them being obtained from Intensive Care Units (ICU) (n = 54; 90%). The disk diffusion method yielded results indicating that 55% of the isolates were sensitive to minocycline, whereas 30% were intermediate and 15% were found to be resistant. Additionally, the MIC results revealed that the resistant rates of the isolates towards ceftazidime, cotrimoxazole and levofloxacin were 46.7%, 1.7% and 5%, respectively. The PCR amplification of three classes of integrons genes indicated that fifteen (25%) of the isolates carried int1, while no detection for intl2 and intl3 was reported. Furthermore, the prevalence of antibiotic resistance genes (sul1, sul2, and Smqnr) was identified in 15 (25%), 6 (10%), and 28 (46.7%) isolates, respectively. ConclusionThe reported increasing rate of antibiotic resistance and mobile genetic elements that could extend the resistance genes to other strains in the hospital, finally it could be an alarming issue for healthcare settings that need special attention to this strain and the epidemiological study on this issue.

A situational analysis of antibiotic prescription, dispensing practices and resistance pattern in Nepal: Are we losing the battle?

Background: Antibiotics are widely utilized to treat infections and provide preventative and therapeutic benefits in animal and human healthcare. However, because of the emergence and spread of resistance mechanisms, which cause bacteria to become less susceptible to antibiotics and other treatments and less effective, antimicrobial resistance (AMR) has grown to be one of the most significant worldwide public health concerns. Low- and middle-income countries (LMICs) such as Nepal have a high rate of infectious illnesses and antibiotic resistance, which can lead to both human and financial losses. Methods: The information for the scenario analysis was acquired through a review of published and grey literature, as well as interviews with important stakeholders from all sectors. Conclusion: Besides knowing all the challenges of antibiotic resistance, the programs assuring towards AMR is conducted in Nepal in very infrequent way. The antibiotic use should be optimize by giving various personalized treatment approaches and accurate diagnosis which plays vital roles in minimizing unnecessary antibiotic prescriptions. We can organize different awareness programs to reduce antibiotic resistance that may enhance the proper use of antibiotic with proper dose and prescription in accordance health care professionals. Interpreting all the problems, government should give more priority to antibiotic resistance and should be able to minimize the problems. If antibiotic resistance is not taken in a very serious way by all the healthcare workers like doctors, nurses, pharmacists, lab technicians, etc. then the battle we are fighting leads to be defeated and problem will never end.

Addressing Challenges in Standardizing Helicobacter pylori Treatment Protocols: Importance and Review.

Helicobacter pylori, one of the top carcinogens, is associated with most cases of gastric cancer-related deaths worldwide.Over the past two decades, the rising rates of antibiotic resistance in the bacterium have reduced the efficacy of conventional antibiotic-based treatments.This underscores the urgency for continued research and novel treatment approaches. Establishing a worldwide accepted physician guideline for antibiotic prescription is crucial to combat antibiotic resistance and improveH. pyloriinfection management. Therefore, it is important to address the challenges thatcomplicatethe establishment of a universally accepted treatment protocol to prescribe an antibiotic regimen to eradicateH. pylori. The answers to the questions of why conventional standard triple therapy remains a first-line treatment choice despite its low efficacy, and how different factors affect therapy choice, are needed to identify these challenges. Hence, this review addresses concerns related toH. pyloritreatment choice, role of antibiotic resistance and patient compliance in treatment outcomes, first-line vs. second-line therapy options, and methods for enhancing existing treatment methods. We also present a chart to aid antibiotic treatment prescription, which may support physician guidelines in this aspect. Eradication ofH. pyloriand patient adherence is paramount in overcoming antibiotic resistance in the bacterium, and our chart summarizes key considerations and suggests novel approaches to achieve this goal.

Antibiotic resistance rates of <i>Klebsiella pneumoniae</i> strains isolated from urine cultures

Aim: Our study aimed to determine the antibiotic resistance rates of K. pneumoniae by retrospectively examining the results of urine culture samples studied in our laboratory. Methods: Urine samples with K. pneumoniae growth, sent to our laboratory from various wards, outpatient clinics, and intensive care units between July 1, 2018 and December 31, 2022 were included in the study and retrospectively examined. Results: The antibiotic to which K. pneumoniae was most resistant was cefixime (53.3%), and the antibiotic to which it was least resistant was imipenem (12.1%). While the lowest resistance rates were observed in the samples of outpatients, the highest resistance rates were observed in the samples of ward patients and to cefixime (81%), amoxicillin clavulanic acid (AMC) (80%), trimethoprim-sulfamethoxazole (TMT/SXT) (74.8%), and ciprofloxacin (72.1%). Ertapenem (48.9%), meropenem (50.2%) and piperacillin-tazobactam (PRP) (57.3%) resistance was found to be higher in intensive care patients. Conclusion: Although fluctuations in resistance rates have been observed over the years, resistance rates have generally been found to be high for antibiotics frequently used in the empirical treatment of urinary tract infections. Re-adjusting treatment according to culture results and keeping resistance rates in mind for empirical treatment will be important for treatment success.

Should we review our prophylaxis approach for increased antibiotic resistance in transrectal prostate biopsy?

This study aims to show the bacteriologic picture of acute prostatitis and bacteremia caused by infective agent after transrectal ultrasound-guided prostate biopsy (TRUSBx) and to determine the resistance rates of the infections in patients undergoing transrectal biopsy and to guide prophylaxis approach before biopsy. The retrospective data of 935 patients who underwent TRUSBx between January 2010 to January 2019 were reviewed. Pre-biopsy urine cultures and antimicrobial susceptibility were obtained. Subsequently, patients admitted to the hospital with any complaint after biopsy were examined for severe infection complications. Of the 430 (61.7%) patients who underwent urine culture before the procedure, 45 (10.5%) had growth; 30 (66.7%) of the growing microorganisms were Escherichia coli. Twenty (44.4%) of all Gram-negative agents in pre-biopsy urine culture were susceptible to quinolone. Post TRUSBx bacteremia was present in 18.2%, urinary system infection in 83.6%, and hospitalization in 61.8% of 55 patients who were admitted to the hospital. In the isolated gram-negative microorganisms, fluoroquinolones resistance in urinary system infections was seen in 40% and bacteremia was seen in 70% of the cases. ESBL-producing Gram-negative bacteria were determined in 40% of infections in blood and 38.5% of urinary system infections in the post biopsy period in the current study. These high antibiotic resistance rates suggest that we better review our pre-procedure prophylaxis approaches.

Investigation of Carbapenemase Production Among Carbapenem-Resistant Pseudomonas aeruginosa Isolates

Background: Pseudomonas aeruginosa is an opportunist organism that causes potentially life threatening nosocomial infections, particularly in immunocompromised patients. Carbapenems are regarded to be the last line of treatment against severe infections caused by multi drug resistant P. aeruginosa isolates. isolates. Production of the carbapenemase enzyme is the primary mechanism of carbapenem resistance and has become a serious health concern worldwide as these enzymes are highly transferable and limit therapeutic alternatives. Rapid detection of carbapenemase production is important for prompt planning the treatment of car-bapenemase-producing isolates and preventing the spread of these strains. This study aimed to investigate carbapenemase produc-tion in carbapenem resistant Pseudomonas aeruginosa isolates by the Carbapenem inactivation method. Materials and Methods: In this retrospective study a total of 172 Pseudomonas aeruginosa isolates were obtained from different samples sent from various clinics to Tokat Gaziosmanpaşa University Research and Application Hospital Microbiology Laboratory between 2016-2019 and were evaluated. Of the 172 isolates, 51 (29.7%) were found to be carbapenem- resistant and included in this investigation. Identification and antibiotic susceptibility tests of the isolates were performed with the Vitek 2 (Biomerieux, France) automated system. Carbapenem sensitivities were also determined by the disc diffusion method. Carbapenemase production in isolates was investigated by the Carbapenem inactivation method. Results: These samples were sent from clinical units, such as neurology (n =10), general surgery (n =8), internal medicine (n =7), and pediatric (n =6). The isolates were identified from wounds (n = 17), sputum (n = 15), blood (n = 11), urine (n = 5), and cerebrospinal fluid (n = 3) samples. Of all the carbapenem –resistant samples 32 (62.8%) were obtained from male, and 19 (37.3%) from female patients. Of the 51 carbapenem resistant isolates, 38 (74.5%) were found to be resistant to both imipenem and meropenem. Eight (15.7%) isolates were found to be resistant to imipenem only, and five (9.8%) isolates were resistant to meropenem. Carbapenemase production was detected in 31 (60.8%) isolates by using using the Carbapenem inactivation method. The antibiotic resistance rates of the carbapenem-resistant isolates were as follows: piperacillin-tazobactam 65%, amikacin 6.8%, gentamicin 15.2%, ceftazidime 34.6%, cefepime 38.3%, ciprofloxacin 26.7%, levofloxacin 24.2%. Conclusions: Rapid identification of carbapenemase enzymes among carbapenem resistant Pseudomonas aeruginosa isolates using phenotypic and genotypic approaches is important to control the transmission of infection caused by carbapenem-resistant isolates and to control the morbidity and mortality associated with them. In this study, the carbapenem inactivation test was seen as a method that can be preferred in the laboratory in terms of its easy and fast application in the detection of carbapenemase production. Key Words: Pseudomonas aeruginosa, Carbapenem inactivation method, Antimicrobial resistance

The influence of attributes on community preferences regarding antibiotic treatment: evidence from a discrete choice model

ABSTRACT Antibiotic resistance (AR) rates in Vietnam are among the highest in Asia, and recent infections due to multi-drug resistance in the country have caused thousands of deaths each year. This study investigated a Vietnamese community’s preferences for antibiotic treatment and its knowledge and attitudes regarding antibiotics. A discrete choice experiment-based survey was developed and administered to the population of interest. The respondents were given sociodemographic-, knowledge- and attitude-related items and 17 pairs of choice tasks. Two hypothetical options were included in each choice task. Latent class analysis was conducted to determine the differences among the respondents’ preferences. Among 1,014 respondents, 805 (79.4%) gave valid questionnaires. A three-latent-class model with four covariates (age, healthcare-related education or career, occupation, and attitude classifications) was used in the analysis. All five attributes significantly influenced the respondents’ decisions. The majority, including young employed respondents with non-healthcare-related work or education, found treatment failure more important. Older respondents who had healthcare-related education/careers and/or appropriate antibiotic use- and antibiotics resistance-related attitudes, regarded contribution to antibiotic resistance as an important attribute in selecting antibiotic treatments. Unemployed individuals with correct knowledge identified the cost of antibiotic treatment as the most essential decision-making factor. Findings suggest minimal antibiotic impact on resistance; only 7.83% view it as amajor concern. The respondents exhibited substantial preference heterogeneity, and the general Vietnamese public had poor knowledge of and attitudes toward antibiotic use and antibiotic resistance. This study emphasizes the need for individual responsibility for antibiotic resistance and appropriate antibiotic use.

Impact of Gram-Negative Bacilli Resistance Rates on Risk of Death in Septic Shock and Pneumonia.

Sepsis is a major cause of morbidity and mortality worldwide. When selecting empiric antibiotics for sepsis, clinicians are encouraged to use local resistance rates, but their impact on individual outcomes is unknown. Improved methods to predict outcomes are needed to optimize treatment selection and improve antibiotic stewardship. We expanded on a previously developed theoretical model to estimate the excess risk of death in gram-negative bacilli (GNB) sepsis due to discordant antibiotics using 3 factors: the prevalence of GNB in sepsis, the rate of antibiotic resistance in GNB, and the mortality difference between discordant and concordant antibiotic treatments. We focused on ceftriaxone, cefepime, and meropenem as the anti-GNB treatment backbone in sepsis, pneumonia, and urinary tract infections. We analyzed both publicly available data and data from a large urban hospital. Publicly available data were weighted toward culture-positive cases. Excess risk of death with discordant antibiotics was highest in septic shock and pneumonia. In septic shock, excess risk of death was 4.53% (95% confidence interval [CI], 4.04%-5.01%), 0.6% (95% CI, .55%-.66%), and 0.19% (95% CI, .16%-.21%) when considering resistance to ceftriaxone, cefepime, and meropenem, respectively. Results were similar in pneumonia. Local data, which included culture-negative cases, showed an excess risk of death in septic shock of 0.75% (95% CI, .57%-.93%) for treatment with discordant antibiotics in ceftriaxone-resistant infections and 0.18% (95% CI, .16%-.21%) for cefepime-resistant infections. Estimating the excess risk of death for specific sepsis phenotypes in the context of local resistance rates, rather than relying on population resistance data, may be more informative in deciding empiric antibiotics in GNB infections.

Risk factors for bacteremic pneumonia and mortality (28-day mortality) in patients with Acinetobacter baumannii bacteremia

BackgroundPatients infected with Acinetobacter baumannii (AB) bacteremia in hospital have high morbidity and mortality. We analyzed the clinical characteristics of pneumonia and nonpneumonia-related AB bloodstream infections (AB BSIs) and explored the possible independent risk factors for the incidence and prognosis of pneumonia-related AB BSIs.MethodsA retrospective monocentric observational study was performed. All 117 episodes of hospital-acquired AB bacteremia sorted into groups of pneumonia-related AB BSIs (n = 45) and nonpneumonia-related AB BSIs (n = 72) were eligible. Univariate/multivariate logistic regression analysis was used to explore the independent risk factors. The primary outcome was the antibiotic susceptibility in vitro of pneumonia-related AB BSIs group. The secondary outcome was the independent risk factor for the pneumonia-related AB BSIs group.ResultsAmong 117 patients with AB BSIs, the pneumonia-related group had a greater risk of multidrug resistant A. baumannii (MDRAB) infection (84.44%) and carbapenem-resistant A. baumannii (CRAB) infection (80%). Polymyxin, minocycline and amikacin had relatively high susceptibility rates (> 80%) in the nonpneumonia-related group. However, in the pneumonia-related group, only polymyxin had a drug susceptibility rate of over 80%. Univariate analysis showed that survival time (day), CRAB, MDRAB, length of hospital stay prior to culture, length of ICU stay prior to culture, immunocompromised status, antibiotics used prior to culture (n > = 3 types), endotracheal tube, fiberoptic bronchoscopy, PITT, SOFA and invasive interventions (n > = 3 types) were associated with pneumonia-related AB bacteremia. The multivariate logistic regression analysis revealed that recent surgery (within 1 mo) [P = 0.043; 0.306 (0.098–0.962)] and invasive interventions (n > = 3 types) [P = 0.021; 0.072 (0.008–0.671)] were independent risk factors related to pneumonia-related AB bacteremia. Multivariate logistic regression analysis revealed that length of ICU stay prior to culture [P = 0.009; 0.959 (0.930–0.990)] and recent surgery (within 1 mo) [P = 0.004; 0.260 (0.105–0.646)] were independent risk factors for mortality in patients with pneumonia-related AB bacteremia. The Kaplan‒Meier curve and the timing test showed that patients with pneumonia-related AB bacteremia had shorter survival time compared to those with nonpneumonia-related AB bacteremia.ConclusionsOur study found that A. baumannii had a high rate of antibiotic resistance in vitro in the pneumonia-related bacteremia group, and was only sensitive to polymyxin. Recent surgery was a significantly independent predictor in patients with pneumonia-related AB bacteremia.

Comparison of the Efficacy of 12-day Concomitant Quadruple Therapy versus 14-day High dose Dual Therapy as a First-line H. pylori Eradication Regimen.

Helicobacter pylori (H. pylori) is the most prevalent infection in the world and is strongly associated with gastric adenocarcinoma, lymphoma and gastric or duodenal ulcers. Different regimens have been used for H. pylori eradication. We aimed to compare the efficacy of two different regimens as first-line H. pylori eradication regimens, in an area with high antibiotic resistance. In this RCT, we assigned 223 patients with H. pylori infection, who were naïve to treatment. They were randomly divided into two groups to receive either 12-day concomitant quadruple therapy (consisting of pantoprazole 40 mg, amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg every 12 hours) or 14-day high dose dual therapy (consisting of esomeprazole 40 mg and amoxicillin 1 g TDS). H. pylori eradication was assessed eight weeks after the end of treatment. H. pylori eradication rate by PP analysis for 12-day concomitant quadruple therapy and 14-day high dose dual therapy were 90.4% and 79.1%, respectively (p=0.02). According to ITT analysis, the eradication rates were 86.2% and 76.3%, respectively (p=0.06). Adverse drug reactions were 12.3% in high dose dual therapy and 36.8% in concomitant quadruple therapy (p<0.001). Twelve-day concomitant therapy seems to be an acceptable regimen for first-line H. pylori eradication in Iran, a country with a high rate of antibiotic resistance. Although, high dose dual therapy did not result in an ideal eradication rate, but it had fewer drug side effects than the 12-day concomitant regimen.

Antimicrobial Susceptibility Profiles of Klebsiella pneumoniae Strains Collected from Clinical Samples in a Hospital in Southern Italy.

Infections caused by antibiotic-resistant bacteria represent a serious threat to global public health. Recently, due to its increased resistance to carbapenems and β-lactams, Klebsiella pneumoniae has become one of the main causes of septicemia, pneumonia, and urinary tract infections. It is crucial to take immediate action and implement effective measures to prevent further spread of this issue. This study aims to report the prevalence and antibiotic resistance rates of K. pneumoniae strains isolated from clinical specimens from 2015 to 2020 at the University Hospital of Salerno, Italy. More than 3,800 isolates were collected from urine cultures, blood cultures, respiratory samples, and others. K. pneumoniae isolates showed broad resistance to penicillin and cephalosporins, and increased susceptibility to fosfomycin and gentamicin. Extended spectrum beta-lactamase (ESBL) isolates accounted for 20-22%. A high percentage of strains tested were resistant to carbapenems, with an average of 40% to meropenem and 44% to ertapenem. The production of ESBLs and resistance to carbapenems is one of the major public health problems. Constant monitoring of drug-resistant isolates is crucial for developing practical approaches in implementing antimicrobial therapy and reducing the spread of K. pneumoniae in nosocomial environments.

Regional variations in antimicrobial susceptibility of community-acquired uropathogenic Escherichia coli in India: Findings of a multicentric study highlighting the importance of local antibiograms

ObjectivesEvidence-based prescribing is essential to optimize patient outcomes in cystitis. This requires knowledge of local antibiotic resistance rates. Diagnostic and Antimicrobial Stewardship (DASH) to Protect Antibiotics (https://dashuti.com/) is a multicentric mentorship program guiding centers in preparing, analyzing and disseminating local antibiograms to promote antimicrobial stewardship in community urinary tract infection. Here, we mapped the susceptibility profile of Escherichia coli from 22 Indian centers. MethodsThese centers spanned 10 Indian states and three union territories. Antibiograms for urinary E. coli from the outpatient departments were collated. Standardization was achieved by regional online training; anomalies were resolved via consultation with study experts. Data were collated and analyzed. ResultsNationally, fosfomycin, with 94% susceptibility (inter-center range 83-97%), and nitrofurantoin, with 85% susceptibility (61-97%), retained the widest activity. The susceptibility rates were lower for co-trimoxazole (49%), fluoroquinolones (31%), and oral cephalosporins (26%). The rates for third- and fourth-generation cephalosporins were 46% and 52%, respectively, with 54% (33-58%) extended-spectrum β-lactamase prevalence. Piperacillin-tazobactam (81%), amikacin (88%), and meropenem (88%) retained better activity; however, one center in Delhi recorded only 42% meropenem susceptibility. Susceptibility rates were mostly higher in South, West, and Northeast India; centers in the heavily populated Gangetic plains, across north and northwest India, had greater resistance. These findings highlight the importance of local antibiograms in guiding appropriate antimicrobial choices. ConclusionsFosfomycin and nitrofurantoin are the preferred oral empirical choices for uncomplicated E. coli cystitis in India, although elevated resistance in some areas is concerning. Empiric use of fluoroquinolones and third-generation cephalosporins is discouraged, whereas piperacillin/tazobactam and aminoglycosides remain carbapenem-sparing parenteral agents.

High prevalence of plasmid-mediated quinolone resistance in escherichia coli strains producing extended-spectrum beta-lactamases isolated from faeces and urine of pregnant women with acute cystitis.

Escherichia coli is the most common etiological agent of urinary tract infections (UTIs). Meanwhile, plasmid-mediated quinolone resistance (PMQR) is reported in E. coli isolates producing extended-spectrum β-lactamases (ESBLs). Furthermore, the reservoirs and mechanisms of acquisition of uropathogenic Escherichia coli (UPEC) strains are poorly understood. On the other hand, UTIs are common in pregnant women and the treatment challenge is alarming. In the present study, 54 pregnant women with acute cystitis were included. A total of 108 E. coli isolates, 54 isolates from UTI and 54 isolates from faeces of pregnant women (same host) were collected. In the antimicrobial susceptibility test, the highest rate of antibiotic resistance was to nalidixic acid (77%, 83/108) and the lowest rate was to imipenem (9%, 10/108). Among the isolates, 44% (48/108) were ESBLs producers. A high frequency of PMQR genes was observed in the isolates. The frequency of PMQR genes qnrS, qnrB, aac(6')-Ib-cr, and qnrA was 58% (63/108), 21% (23/108), 9% (10/108), and 4% (4/108), respectively. Meanwhile, PMQR genes were not detected in 24% (20/85) of isolates resistant to nalidixic acid and/or fluoroquinolone, indicating that other mechanisms, i.e. chromosomal mutations, are involved in resistance to quinolones, which were not detected in the present study. In ESBL-producing isolates, the frequency of PMQR genes was higher than that of non-ESBL-producing isolates (81% vs. 53%). Meanwhile, UTI and faeces isolates mainly belonged to phylogenetic group B2 (36/54, 67% and 25/54, 46%, respectively) compared to other phylogenetic groups. In addition, virulence factors and multidrug-resistant (MDR) were mainly associated with phylogenetic group B2. However, predominant clones in faeces were not found in UTIs. Rep-PCR revealed the presence of 85 clones in patients. Among the clones, 40 clones were detected only in faeces (faeces-only), 35 clones only in UTI (UTI-only) and 10 clones in both faeces and UTI (faeces-UTI). We found that out of 10 faeces-UTI clones, 5 clones were present in the host's faeces flora. This study revealed a high rate of resistance to the quinolone nalidixic acid and a widespread distribution of PMQR genes in MDR E. coli strains producing ESBLs. The strains represented virulence factors and phylogenetic group B2 are closely associated with abundance in UTI and faeces. However, the predominant clones in faeces were not found in UTIs and it is possible that rep-PCR is not sufficiently discriminating clones.

Molecular Prevalence and Geographical Variations of Carbapenem-Resistant Klebsiella pneumoniae ST15 Isolates in a Tertiary Hospital in Ningbo, China.

BACKGROUND In China, the most prevalent type of CRKP is ST11, but the high-risk clone ST15 has grown in popularity in recent years, posing a serious public health risk. Therefore, we investigated the molecular prevalence characteristics of ST15 CRKP detected in a tertiary hospital in Ningbo to understand the current potential regional risk of ST15 CRKP outbreak. MATERIAL AND METHODS We collected and evaluated 18 non-duplicated CRKP strains of ST15 type for antibiotic resistance. Their integrons, virulence genes, and resistance genes were identified using polymerase chain reaction (PCR), and their homology was determined using MALDI-TOF MS. RESULTS The predominant serotype of 18 ST15 CRKP strains was K5. ST15 CRKP exhibited the lowest antimicrobial resistance to Cefoperazone/sulbactam (11.1%), followed by trimethoprim/sulfamethoxazole (22.2%). Resistance gene testing revealed that 14 out of 18 ST15 CRKP strains (77.8%) carried Klebsiella pneumoniae carbapenemase 2 (KPC-2), whereas all ST15 CRKP integrons were of the intI1 type. Furthermore, virulence gene testing revealed that all 18 ST15 CRKP strains carried ybtS, kfu, irp-1, and fyuA genes, followed by the irp-2 gene (17 strains) and entB (16 strains). The homology analysis report showed that 2 clusters had closer affinity, which was mainly concentrated in classes C and D. CONCLUSIONS The ST15 CRKP antibiotic resistance rates demonstrate clear geographical differences in Ningbo. Additionally, some strains carried highly virulent genes, indicating a possible evolution towards carbapenem-resistant highly virulent strains. To reduce the spread of ST15 CRKP, we must rationalize the clinical use of antibiotics and strengthen resistance monitoring to control nosocomial infections.

Fourteen-day vonoprazan-based bismuth quadruple therapy for H. pylori eradication in an area with high clarithromycin and levofloxacin resistance: a prospective randomized study (VQ-HP trial)

Potassium-competitive acid blockers (P-CABs) provide potent acid inhibition, yet studies on P-CAB-based quadruple therapy for H. pylori eradication are limited. We theorized that integrating bismuth subsalicylate into a quadruple therapy regimen could enhance eradication rates. However, data on the efficacy of vonoprazan bismuth quadruple therapy are notably scarce. Therefore, the aim of this study was to evaluate the efficacy of vonoprazan-based bismuth quadruple therapy in areas with high clarithromycin and levofloxacin resistance. This was a prospective, single-center, randomized trial conducted to compare the efficacy of 7-day and 14-day vonoprazan-based bismuth quadruple therapy for H. pylori eradication between June 1, 2021, and March 31, 2022. Qualified patients were randomly assigned to the 7-day or 14-day regimen (1:1 ratio by computer-generated randomized list as follows: 51 patients for the 7-day regimen and 50 patients for the 14-day regimen). The regimens consisted of vonoprazan (20 mg) twice daily, bismuth subsalicylate (1024 mg) twice daily, metronidazole (400 mg) three times daily, and tetracycline (500 mg) four times daily. CYP3A4/5 genotyping and antibiotic susceptibility tests were also performed. Successful eradication was defined as 13negative C-UBTs 4 weeks after treatment. The primary endpoint was to compare the efficacy of 7-day and 14-day regimens as first-line treatments, which were assessed by intention-to-treat (ITT) and per-protocol (PP) analyses. The secondary endpoints included adverse effects. A total of 337 dyspeptic patients who underwent gastroscopy were included; 105 patients (31.1%) were diagnosed with H. pylori infection, and 101 patients were randomly assigned to each regimen. No dropouts were detected. The antibiotic resistance rate was 33.3% for clarithromycin, 29.4% for metronidazole, and 27.7% for levofloxacin. The CYP3A4 genotype was associated with 100% rapid metabolism. The H. pylori eradication rates for the 7-day and 14-day regimens were 84.4%, 95% CI 74.3–94.2 and 94%, 95% CI 87.4–100, respectively (RR difference 0.25, 95% CI 0.03–0.53, p value = 0.11). Interestingly, the 14-day regimen led to 100% eradication in the clarithromycin-resistant group. Among the patients in the 7-day regimen group, only two exhibited resistance to clarithromycin; unfortunately, neither of them achieved a cure from H. pylori infection. The incidence of adverse events was similar in both treatment groups, occurring in 29.4% (15/51) and 28% (14/50) of patients in the 7-day and 14-day regimens, respectively. No serious adverse reactions were reported. In conclusion, 14 days of vonoprazan-based bismuth quadruple therapy is highly effective for H. pylori eradication in areas with high levels of dual clarithromycin and levofloxacin resistance.