Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance

The gram-negative bacterium Helicobacter pylori(H.pylori)causes chronic gastritis,gastric and duodenal ulcers,gastric cancer and mucosa-associated lymphoid tissue lymphoma.Treatment is recommended in all symptomatic patients.The current treatment options for H.pylori infection are outlined in this review in light of the recent challenges in eradication success,largely due to the rapid emergence of antibiotic resistant strains of H.pylori.Antibiotic resistance is a constantly evolving process and numerous studies have shown that the prevalence of H.pylori antibiotic resistance varies significantly from country to country,and even between regions within the same country.In addition,recent data has shown that previous antibiotic use is associated with harbouring antibiotic resistant H.pylori.Local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy.Antimicrobial resistance is assessed by H.pylori culture and antimicrobial susceptibility testing.Recently developed molecular tests offer an attractive alternative to culture and allow for the rapid molecular genetic identification of H.pylori and resistance-associated mutations directly from biopsy samples or bacterial culture material.Accumulating evidence indicates that surveillance of antimicrobial resistance by susceptibility testing is feasible and necessary to inform clinicians in their choice of therapy for management of H.pylori infection.

Evaluation of rational use of antimicrobial agents in a Brazilian intensive care unit

The present study sought to assess the rational use of antimicrobial agents in a Brazilian intensive care unit (ICU) and its association with antimicrobial resistance in elderly patients admitted to the unit. Results: Choice of empiric and sensitivity-guided therapy was inadequate in > 80% and 59% of cases respectively. Inadequate antimicrobial therapy, whether empiric or sensitivity-guided, was positively correlated with bacterial resistance (r = 0.316;p = 0.001). Sensitivity testing revealed a 46.5% resistance rate to eight out of the ten most commonly used antibiotics. Multiple drug-resistant organisms were found in 40.8% of patients. A significant increase was observed in the number of multidrug-resistant samples between 2006/2007 and 2008 (r = 0.41, p = 0.006), (r = 0.598, p = 0.001), (r = 0.688, p = 0.00). Conclusion: We found a high rate of antibiotic misuse in the study sample. Inadequate therapy was correlated with resistance to antimicrobial agents.

Antimicrobial Stewardship: Knowledge and Attitudes of Pharmacy Staff on Antibiotic Dispensing Patterns, Use and Resistance in Benin

Background: One of the key drivers for the emergence and spread of antimicrobial resistance (AMR) is non-prudent antibiotic use, which results in selection pressure toward relevant bacteria. Pharmacy staffs have pivotal roles in facilitating the prudent use of antibiotics through antimicrobial stewardship programs. Due to limited information in Benin, this study assessed the knowledge and attitudes of pharmacy staffs on antibiotic use and resistance. Materials and Methods: This cross-sectional study was conducted among 159 pharmacy staffs using a structured questionnaire from August 2018 to December 2018 in Benin. Data analysis was done by using Stata version 13.0. Results: Of the 159 participants, 54.8% knew the definition of antibiotic therapy and 66.9% knew the definition of probabilistic antibiotic therapy. The majority (88.1%) of the participants thought that the choice of antibiotics was made according to the pathology, while 60.4% thought that it depended on the pathology and the germ involved. 49.02% of dispensers in pharmacies stated that half of the patients had requested treatment without providing a prescription at the pharmacy. The top three antibiotics that were dispensed without a prescription include amoxicillin (98.1%), cloxacillin (76.7%) and metronidazole (57.2%), all from the Access group of antibiotics. Conclusion: These results underscore the need for educational and training interventions targeting specific professional groups. There is an urgent need for regulatory measures and public awareness through improved antimicrobial stewardship to limit this practice.

Knowledge, Attitudes, and Practices of Poultry Farmers on Antimicrobial Use and Resistance in Kitwe, Zambia: Implications on Antimicrobial Stewardship

Introduction: The inappropriate antimicrobial usage (AMU) in chicken production has led to an increase in the prevalence of antimicrobial resistance (AMR). In Zambia, there is little information documented regarding the knowledge, attitude, and practices of poultry farmers on AMU and AMR. Therefore, this study assessed the knowledge, attitude and practices regarding AMU and AMR among poultry farmers in Kitwe, Zambia. Methods: This was a cross-sectional study conducted among 106 poultry farmers from November to December 2021 using a structured questionnaire. Data analysis was done using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: Overall, of the 106 participants, 90.6% knew what antimicrobials were, but only 29.2% were aware of AMR. The study showed that 46.2% of the participants had low knowledge, 71.7% had negative attitudes, and 61.3% had poor practices regarding AMR. The prevalence of antibiotic use in poultry production was 83%. The most used antimicrobials were tetracycline (84%) and gentamicin (35.2%). The commonly reported reason for the use of antimicrobials was for the treatment (93.2%) and prevention (89.8%) of diseases. Further, 76.9% of the administered antimicrobials were usually done without veterinarian consultation or prescription. Conclusion: The study shows that there was high AMU in poultry farms in Kitwe. However, there was low knowledge, negative attitude, and poor practices towards AMU and AMR. Therefore, there is a need for educational and sensitisation programmes regarding AMU and AMR among poultry farmers in Kitwe, Zambia. Alongside this, antimicrobial stewardship and surveillance systems should be strengthened in the livestock production sector. This will ensure food safety and public health.

Pathogenicity and Antimicrobial Resistance in Coagulase-Negative Staphylococci

The coagulase-negative staphylococci (CoNS) group was considered saprophytic or rarely pathogenic for many years. Since the first case of septicemia caused by CoNS, there has been a progressive increase in the prevalence of healthcare-associated infections caused by CoNS. The CoNS group has emerged as one of the main causes of nosocomial infections related to vascular catheters and prostheses, especially among immunocompromised patients. This gradual increase in infections is due to the change in the relationship between patients and procedures since CoNS are closely related to devices implanted in the human body. CoNS are successful in colonizing the host because they have several virulence mechanisms, such as biofilm formation and production of enzymes and toxins, in addition to several mechanisms of resistance to antimicrobials. Despite their great clinical relevance, few studies have focused on CoNS’s pathogenicity and resistance to antimicrobials, which reveals the current need to better understand the factors by which this group became pathogenic to humans and other animals. This review aims to synthesize the aspects related to the pathogenicity and antimicrobial resistance in CoNS.

Analysis of Multi-Drug Resistant Organism Surveillance and Antimicrobial Resistance Early Warning in a Hospital in 2022

Objective:To determine the clinical distribution of multi-drug resistant organism(MDRO)in Jiangyan Hospital and the monitoring and warning of drug-resistance bacteria to provide an important basis for guiding the application of broad-spectrum antibiotics in clinical treatment and reducing the occurrence of nosocomial infection.Methods:Retrospective screening and analysis were conducted on the pathogenic strains of hospitalized patients in our hospital in 2022.Results:A total of 2,769 strains of pathogenic bacteria and 390 strains of MDRO were detected and isolated in our hospital in 2022;the detection rate of MDRO was 14.08%.A total of 516 strains(18.64%)Klebsiella pneumoniae(KP)and 62 strains(12.02%)of carbapenem-resistant Klebsiella pneumoniae(CR-KP)were detected;436 strains(15.75%)of Escherichia coli(ECO)were detected,including 8 strains(1.83%)of CR-ECO;342 strains(12.35%)of Pseudomonas aeruginosa(PA)and 116 strains(33.92%)of CR-PA were detected;there were 194 strains(7.01%)of Acinetobacter baumannii(AB),among which 125 strains(64.43%)were CR-AB;there were 291 strains(10.51%)of Staphylococcus aureus,among which 79 strains(27.15%)of methicillin-resistant Staphylococcus aureus(MRSA)were detected;78 strains(2.82%)of Enterococcus faecalis were detected,and vancomycin-resistant enterococcus(VRE)was not detected.The first five MDROs were CR-AB,CR-PA,MRSA,CR-KP,and CR-ECO.The top five departments with the highest MDRO detection rate in 2022 were the ICU(37.44%),the Pulmonology Department(ward 13;31.03%),the Department of Rehabilitation(ward 5;6.67%),the Department of Neurosurgery(ward 11;4.62%),and the Department of General Surgery(ward 10;3.59 The resistance rate of antibacterial drugs is divided into four levels for early warning:30%to 40%,41%to 50%,51%to 75%,and 75%or more.Conclusion:Our hospital should strengthen the monitoring of antimicrobial resistance warning related to MDRO and the abuse of antimicrobial drugs.Based on the results of drug sensitivity and antimicrobial resistance warning,the use of antibiotics should be standardized in clinical practice to reduce nosocomial infection。

Knowledge, Attitudes and Practices of Antibiotic Use and Antimicrobial Resistance among Medical Students in a Private University in Dominica, West Indies

Antibiotics are indispensable to maintaining human health, however, their overuse has resulted in resistant organisms which present a significantly higher burden to the low to middle income countries, due to the high incidence of communicable diseases. Insufficient antimicrobial-related training for physicians during their undergraduate education could have a negative impact on their prescribing. This study assessed the knowledge, attitudes and practices of antibiotic use and antimicrobial resistance among medical students in a private university in Dominica, a resource-limited country, in order to facilitate more effective education of these future prescribers. A cross-sectional study was undertaken with the medical students from February 2021 to April 2021 using a 36-item questionnaire. Data analysis was achieved using descriptive statistics. A total of 85 students participated in the study, majority (70%) were female, African, aged 23.8 ± 4.6 years and single. Between 64 and 99% of the respondents reported no risk factors for communicable diseases and demonstrated a low to moderate (10% - 40%) negative response to knowledge-related questions. The majority (70%) of the respondents who had used antibiotics in the past 12 months reported efficacy and limited side-effects, but confirmed lack of knowledge about the classes of antibiotics prescribed to them. Almost half of the medical students (48%) reported having abused antibiotics, while about a third (35%) of the respondents reported sharing antibiotics with friends or loved ones in the past. There was no significant association between age, gender, and the medical students’ knowledge of antibiotic resistance (p > 0.05). However, they reported that they would like more education on antimicrobial use and resistance. The medical students in this study showed knowledge of antimicrobial resistance, but lacked comprehension of components of antimicrobial stewardship, including prevention of inappropriate use and classes of antibiotics. Therefore, steps need to be taken to prepare medical students for antimicrobial resistance and stewardship initiatives effectively.

Six-year analysis of key monitoring for bacterial strain distribution and antibiotic sensitivity in a hospital

BACKGROUND With the widespread use of antimicrobial drugs,bacterial resistance has become a significant problem,posing a serious threat to public health.The prevalence of clinical infection strains in hospitals and their drug sensitivities are key to the appropriate use of antibiotics in clinical practice.AIM To identify prevalent bacteria and their antibiotic resistance profiles in a hospital setting,thereby guiding effective antibiotic usage by clinicians.METHODS Specimens from across the institution were collected by the microbiology laboratory.The VITEK 2 compact fully automatic analyzer was used for bacterial identification and antibiotic sensitivity testing,and the WHONET5.6 software was utilized for statistical analysis.RESULTS A total of 12062 bacterial strains of key monitoring significance were detected.Staphylococcus aureus demonstrated widespread resistance to penicillin,but none of the strains were resistant to vancomycin or linezolid.Moreover,219 strains of methicillin-resistant coagulase-negative staphylococci and 110 strains of methicillin-resistant Staphylococcus aureus were detected.Enterococcus faecalis showed moderate resistance to the third-generation quinolones ciprofloxacin and levofloxacin,but its resistance to nitrofurantoin and tetracycline was low.Enterococcus faecium displayed significantly lower resistance to third-and fourthgeneration quinolones than Enterococcus faecalis.The resistance of two key monitoring strains,Escherichia coli and Klebsiella pneumoniae,to piperacillin/tazobactam was 5%-8%.However,none of the Escherichia coli and Klebsiella pneumoniae strains were resistant to meropenem.The resistance of Acinetobacter baumannii to piperacillin/sulbactam was nearly 90%.Nonetheless,the resistance to tigecycline was low,and Pseudomonas aeruginosa demonstrated minimal resistance in the antibiotic sensitivity test,maintaining a resistance of<10%to the cephalosporin antibiotics cefotetan and cefoperazone over the last 6 years.The resistance to amikacin remained at 0.2%over the past 3 years.CONCLUSION Our hospital’s overall antibiotic resistance rate was relatively stable from 2017 to 2022.The detection rates of key monitoring strains are reported quarterly and their resistance dynamics are monitored and communicated to the entire hospital,which can guide clinical antibiotic selection.

Antimicrobial peptides: new hope in the war against multidrug resistance

The discovery of antibiotics marked a golden age in the revolution of human medicine. However,decades later, bacterial infections remain a global healthcare threat, and a return to the pre-antibiotic era seems inevitable if stringent measures are not adopted to curb the rapid emergence and spread of multidrug resistance and the indiscriminate use of antibiotics. In hospital settings, multidrug resistant(MDR) pathogens, including carbapenem-resistant Pseudomonas aeruginosa, vancomycin-resistant enterococci(VRE), methicillin-resistant Staphylococcus aureus(MRSA), and extendedspectrum β-lactamases(ESBL) bearing Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae are amongst the most problematic due to the paucity of treatment options,increased hospital stay, and exorbitant medical costs. Antimicrobial peptides(AMPs) provide an excellent potential strategy for combating these threats. Compared to empirical antibiotics, they show low tendency to select for resistance, rapid killing action, broad-spectrum activity, and extraordinary clinical efficacy against several MDR strains. Therefore, this review highlights multidrug resistance among nosocomial bacterial pathogens and its implications and reiterates the importance of AMPs as next-generation antibiotics for combating MDR superbugs.

Development of Helicobacter pylori treatment: How do we manage antimicrobial resistance?

Helicobacter pylori(H. pylori) antimicrobial resistance is an urgent, global issue. In2017, the World Health Organization designated clarithromycin-resistant H.pylori as a high priority bacterium for antibiotic research and development. In addition to clarithromycin, resistance to metronidazole and fluoroquinolones has also increased worldwide. Recent international guidelines for management of H.pylori infection recommend bismuth or non-bismuth quadruple therapy for 14 d as a first-line treatment for H. pylori in areas of high clarithromycin and/or metronidazole resistance. Although these treatment regimens provide acceptable H. pylori eradication rates, the regimens used should not contribute to future resistance of H. pylori to antimicrobials. Moreover, these regimens can promote resistance, due to prolonged therapy with multiple antibiotics. A new strategy that can eradicate H. pylori as well as reduce the antibiotics used is required to prevent future antimicrobial resistance in H. pylori. Dual-therapy with vonoprazan and amoxicillin could be a breakthrough for H. pylori eradication in an era of growing antimicrobial resistance. This regimen may provide a satisfactory eradication rate of H. pylori and also minimize antimicrobial resistance due to single antibiotic use and the strong inhibitory effect of vonoprazan on gastric acid secretion.

A review of global initiatives to fight antibiotic resistance and recent antibiotics' discovery

Data from across the world have shown an overall decline in the antibiotic pipeline and continually rising resistance to all first-line and last-resort antibiotics. The gaps in our knowledge of existing prevalence and mechanisms of antibiotic resistance(ABR) are all too well known. Several decades of antibiotic abuse in humans, animals, and agricultural practices have created health emergency situations and huge socio-economic impact. This paper discusses key findings of the studies conducted by several national and international collaborative organizations on the current state of affairs in ABR.Alongside, a brief overview of the antibacterial agents' discovery in recent years approved by the US FDA is discussed.

Antimicrobial resistance of abnormal vaginal discharges microorganisms in Ouagadougou,Burkina Faso

Objective:To assess the prevalence of bacterial strains and fungal strains infecting the vaginal tract and test their sensitivity to antibiotics in women attending Saint Camille Medical Centre in Ouagadougou.Methods:From January 2008 to December 2009,a total of 2000 vaginal swabs were cultivated for bacterial and fungal identification and isolation.Furthermore,bacterial strains were tested for their susceptibility to several antibiotics used in routine in the centre. Results:The results revealed that microbial isolation and identification was attempted for 1536/2000 sample,a positivity rate of 76.80%.Candida albicans(48.76%),followed by Escherichia coli(16.67%),Streptococcus agalactiae(8-14%) and Staphylococcus aureus(7.55%) were the major agents of genital tract infections in patients.Mycoplasma hominis and Ureaplasma urealyticum combined accounted for less than 7%.Trichomonas vaginalis was identified in 1.04%coses.The antimicrobial tests revealed that the microorganisms developed resistance to several antibiotics including beta lactams.However,antibiotics such as cefamenzol,ciprofloxacin and norfloxacin were still active on these bacteria.Conclusions:The results reveal that many sexually active women are infected by one or more microbial pathogens,probably because of the lock of hygiene or the adoption of some risky behaviors,such as not using condoms or having multiple sexual partners.Efforts should be made to address these points in the country.

Lack of new antiinfective agents: Passing into the pre-antibiotic age?

The lack of newly developed antibiotics, together with the increase in multi-resistance of relevant pathogenic bacteria in the last decades, represents an alarming signal for human health care worldwide. The number of severely infected persons increases not only in developing but also in highly industrialized countries. This relates in first line to the most severe form of a bacterial infection, sepsis and the septic shock syndrome, with high mortality on critical care units. No particular anti-sepsis drug is available, and the therapy with conventional antibiotics more and more fails to provide a survival benefit. Due to the fact that the pharmaceutical industry has withdrawn to a high degree from the development of anti-infectious agents, a huge challenge for health care is approaching in the 21 st century. In this article, these problems are outlined and possible alternatives are presented which may be helpful to solve the problem.

Antimicrobial usage and resistance in beef production

Antimicrobials are critical to contemporary high-intensity beef production. Many different antimicrobials are approved for beef cattle, and are used judiciously for animal welfare, and controversially, to promote growth and feed efficiency. Antimicrobial administration provides a powerful selective pressure that acts on the microbial community, selecting for resistance gene determinants and antimicrobial-resistant bacteria resident in the bovine flora. The bovine microbiota includes many harmless bacteria, but also opportunistic pathogens that may acquire and propagate resistance genes within the microbial community via horizontal gene transfer. Antimicrobial-resistant bovine pathogens can also complicate the prevention and treatment of infectious diseases in beef feedlots,threatening the efficiency of the beef production system. Likewise, the transmission of antimicrobial resistance genes to bovine-associated human pathogens is a potential public health concern. This review outlines current antimicrobial use practices pertaining to beef production, and explores the frequency of antimicrobial resistance in major bovine pathogens. The effect of antimicrobials on the composition of the bovine microbiota is examined, as are the effects on the beef production resistome. Antimicrobial resistance is further explored within the context of the wider beef production continuum, with emphasis on antimicrobial resistance genes in the food chain, and risk to the human population.

Prevalence and Antimicrobial Susceptibility Pattern of Methicillin Resistance Staphylococcus in a Sudanese Surgical Ward

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is important nosocomial pathogen. Aim: In this paper, we determined the prevalence and the antibiotic susceptibility pattern of (MRSA) in a Sudanese surgical ward. Method: A total of 200 post-operative surgical specimens were collected from patients hospitalized in gastrointestinal tract (GIT) surgical ward in Ibn Sina hospital, Khartoum, Sudan and were subjected to MRSA screening and sensitivity test. Key findings: Out of 35 strains of Staphylococcus aureus isolated from surgical samples, 25 (71.4%) were found to be MRSA. Almost all MRSA strains were resistance to Methicillin, 96% to Ofloxacin, 92% to Pencillin G, 24% to Amikacin and 4% to Vancomycin. Cross-resistance was obviously detected. Conclusion: The present study detected alarming levels of S. aureus (MRSA) isolates, at the same time presence of high cross-resistance to other antibiotics.

Antimicrobial resistance in clinically important biofilms

A biofilm contains a consortium of cohesive bacterial cells forming a complex structure that is a sedentary, but dynamic, community. Biofilms adhere on biotic and abiotic surfaces, including the surfaces of practically all medical devices. Biofilms are reported to be responsible for approximately 60% of nosocomial infections due to implanted medical devices, such as intravenous catheters, and they also cause other foreign-body infections and chronic infections. The presence of biofilm on a medical device may result in the infection of surrounding tissues and failure of the device, necessitating the removal and replacement ofthe device. Bacteria from biofilms formed on medical devices may be released and disperse, with the potential for the formation of new biofilms in other locations and the development of a systemic infection. Regardless of their location, bacteria in biofilms are tolerant of the activities of the immune system, antimicrobial agents, and antiseptics. Concentrations of antimicrobial agents sufficient to eradicate planktonic cells have no effect on the same microorganism in a biofilm. Depending on the microbial consortium or component of the biofilm that is involved, various combinations of factors have been suggested to explain the recalcitrant nature of biofilms toward killing by antibiotics. In this mini-review, some of the factors contributing to antimicrobial resistance in biofilms are discussed.

Advances in Research of TCM Antimicrobial Resistance

This paper analyzed and summarized the mechanism of antimicrobial resistance,the characteristics and advantages of traditional Chinese medicine(TCM)antimicrobial resistance,and ingredients of antimicrobial resistance,in the hope of providing a theoretical basis and research idea for tackling the problem of antimicrobial resistance and developing new TCM green antibiotics.

In vitro antimicrobial and synergistic effect of essential oil from the red macroalgae Centroceras clavulatum (C. Agardh) Montagne with conventional antibiotics

Objective:To study the chemical profile,antimicrobial properties,and synergistic effect with known antibiotics of essential oil extracted from the marine red macroalgae Centroceras clavulatum(C.Agardh)Montagne,collected in Morocco.Methods:The chemical composition of the oil was analyzed by gas chromatography-mass spectrometry.The oil was evaluated for antibacterial(Pseudomonas aeruginosa,Escherichia coli,Bacillus subtilis,Micrococcus luteus,Staphylococcus aureus,and Klebsiella pneumoniae),and antifungal activity(Candida albicans,Candida glabrata,Candida krusei,and Candida parapsilosis),by the disc diffusion method.The minimum inhibitory and minimum microbicidal concentrations of the oil were determined,as well as the synergistic effects of its application combined with the antibiotics ciprofloxacin and fluconazole,by the checkerboard method.Results:Thirty molecules were identified in the essential oil,comprising 96.27%of the total oil composition.Monoterpenes such as carvacrol(36.06%)were the most abundant compounds,followed by caryophyllene(14.67%),endo-borneol(9.04%),pyroterebic acid(3.23%)and caryophyllene oxide(3.13%).The oil exhibited a moderate antimicrobial activity with inhibition zone diameters ranging from 9.0 to 15.0 mm.The minimum inhibitory concentration values varied between 0.9 and 14.7 mg/mL,and Bacillus subtilis and Escherichia coli were the more sensitive bacteria with 0.9 and 1.9 mg/mL,respectively.The minimum microbicidal concentration values ranged from 0.4 to 14.7 mg/mL.A significant synergic action was observed when the oil was applied in combination with ciprofloxacin and fluconazole,with fractional inhibitory concentration index values ranging from 0.31 to 0.50.Synergy was found in 80%of the combinations and a 2 to 16-fold reduction of antibiotics MIC was observed.Conclusions:Our findings suggest that the essential oil of Centroceras clavulatum should be further appraised for its potential use in the management of multi-drug resistant microorganisms,with the purpose to restore the activity of standard antimicrobial drugs.

湖南省细菌耐药监测网2012—2021年呼吸道分离菌耐药性监测

目的了解2012—2021年湖南省细菌耐药监测网呼吸道分离菌的分布和耐药性变迁。方法细菌鉴定和药敏试验统一按全国细菌耐药监测网(CARSS)细菌耐药监测技术方案执行,剔除重复菌株。按照美国临床实验室标准化协会(CLSI)2022年标准判断细菌对抗菌药物的敏感性,应用WHONET 5.6软件进行统计描述。结果2012—2021年湖南省细菌耐药监测网呼吸道标本共分离976984株细菌,其中革兰阳性菌185642株(19.0%),革兰阴性菌791342株(81.0%)。分离自成人患者呼吸道标本排名前五位的细菌是肺炎克雷伯菌(25.2%)、铜绿假单胞菌(17.0%)、鲍曼不动杆菌(14.6%)、大肠埃希菌(6.7%)和金黄色葡萄球菌(5.8%)。分离自儿童患者呼吸道标本排名前五位的细菌是金黄色葡萄球菌(17.7%)、肺炎链球菌(15.6%)、大肠埃希菌(13.5%)、肺炎克雷伯菌(13.1%)和流感嗜血杆菌(10.8%)。肺炎克雷伯菌、大肠埃希菌和阴沟肠杆菌对替加环素、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、碳青霉烯类、阿米卡星耐药率较低(<15%)。肺炎克雷伯菌对亚胺培南、美罗培南的耐药率分别从2012—2013年的3.5%、4.2%逐渐上升至2020—2021年的9.5%、11.5%,对头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、阿米卡星、妥布霉素、环丙沙星和左氧氟沙星的耐药率呈上升趋势。大肠埃希菌和阴沟肠杆菌对氨曲南、氨基糖苷类和氟喹诺酮类的耐药率呈下降趋势。铜绿假单胞菌对多黏菌素耐药率较低(<6%),鲍曼不动杆菌对替加环素和多黏菌素耐药率较低(<6%)。铜绿假单胞菌对β-内酰胺类、氨基糖苷类和氟喹诺酮类耐药率下降。鲍曼不动杆菌对头孢哌酮/舒巴坦的耐药率从18.0%上升至43.7%,对哌拉西林/他唑巴坦、亚胺培南、氟喹诺酮类和米诺环素的耐药率呈上升趋势。未发现对万古霉素、替考拉宁和利奈唑胺耐药的金黄色葡萄球菌。成人和儿童患者耐甲氧西林金黄色葡萄球菌(MRSA)检出率分别为37.8%(14208/37594)、22.7%(10874/47882)。结论湖南省2012—2021年呼吸道分离细菌以革兰阴性菌为主,成人和儿童患者分离的优势细菌并不相同。大肠埃希菌、阴沟肠杆菌和铜绿假单胞菌对部分抗菌药物的耐药率不断下降。肺炎克雷伯菌对碳青霉烯类耐药率逐渐上升。应持续高效做好细菌耐药监测,为临床使用抗菌药物提供数据支持。