Antimicrobial resistance surveillance of Bacteroides fragilis isolated from blood cultures, Europe, 2022 (ReSuBacfrag).

OBJECTIVES: Bacteroides fragilis is the most frequent cause of anaerobic bacteraemia. Although recent data suggest a rise in antimicrobial resistance (AMR) of this and other anaerobic bacteria, surveillance remains limited due to a lack of both data availability and comparability. However, a newly introduced standardised method for antimicrobial susceptibility testing (AST) of anaerobic bacteria has made larger scale surveillance possible for the first time. The aim of this study was to investigate phenotypic AMR of Bacteroides fragilis isolates from bacteraemia across Europe in 2022. METHODS: In a multicentre approach, clinical microbiology laboratories in Europe were invited to contribute results of AST for Bacteroides fragilis blood culture isolates (including only the first isolate per patient and year). AST of a selection of four antibiotics was performed locally by participating laboratories in a prospective or retrospective manner, using the new EUCAST disc diffusion method on fastidious anaerobe agar (FAA-HB). RESULTS: A total of 16 European countries reported antimicrobial susceptibilities in 449 unique isolates of Bacteroides fragilis from blood cultures in 2022. Clindamycin demonstrated the highest resistance rates (20.9%, range 0 - 63.6%), followed by piperacillin-tazobactam (11.1%, 0-54.5%), meropenem (13.4%, 0-45.5%), and metronidazole (1.8%, 0-20.0%), all with wide variation between countries. CONCLUSION: Considering that the mean resistance rates across Europe were higher than expected for three of the four anti-anaerobic antibiotics under surveillance, both local AST of clinically relevant isolates of Bacteroides fragilis and continued surveillance on an international level is warranted.

Application of cefuroxime in the eradication therapy of Helicobacter pylori infection: A review article.

BACKGROUND: Helicobacter pylori infection and its associated diseases represent a significant global health concern. Patients who cannot use amoxicillin pose a therapeutic challenge and necessitate alternative medications. Preliminary research indicates that cefuroxime demonstrates promising potential for eradicating H. pylori infection, and there is a lack of comprehensive review articles on the use of cefuroxime. MATERIALS AND METHODS: This study conducts a thorough systematic literature review and synthesis. A comprehensive systematic search was conducted in PubMed, Web of Science, EMBASE, China National Knowledge Infrastructure, China Biology Medicine disc, and Wanfang Data up to January 13, 2024. The search strategy utilized the following keywords: (Cefuroxime) AND (Helicobacter pylori OR Helicobacter nemestrinae OR Campylobacter pylori OR Campylobacter pylori subsp. pylori OR Campylobacter pyloridis OR H. pylori OR Hp) for both English and Chinese language publications. Sixteen studies from five different countries or regions were included in final literature review. RESULTS: Analysis results indicate that H. pylori is sensitive to cefuroxime, with resistance rates similar to amoxicillin being relatively low. Regimens containing cefuroxime have shown favorable eradication rates, which were comparable to those of the regimens containing amoxicillin. Regarding safety, the incidence of adverse reactions in cefuroxime-containing eradication regimens was comparable to that of amoxicillin-containing regimens or other bismuth quadruple regimens, with no significant increase in allergic reactions in penicillin-allergic patients. Regarding compliance, studies consistently report high compliance rates for regimens containing cefuroxime. CONCLUSION: Cefuroxime can serve as an alternative to amoxicillin for the patients allergic to penicillin with satisfactory efficacies, safety, and compliance.

Prevalence and Clinical Characteristics of Bacterial Pneumonia in Neurosurgical Emergency Center Patients: A Retrospective Study Spanning 13 Years at a Tertiary Center.

Patients with brain injuries are at a heightened susceptibility to bacterial pneumonia, and the timely initiation of empiric antibiotic treatment has been shown to substantially reduce mortality rates. Nevertheless, there is a need for knowledge regarding the resistance and prevalence of pulmonary bacterial infections in this patient population. To address this gap, a retrospective study was conducted at a neurosurgical emergency center, focusing on patients with brain injuries. Among the entire patient population, a total of 739 individuals (18.23%) were identified as having bacterial pneumonia, consisting of 1489 strains of Gram-negative bacteria and 205 strains of Gram-positive bacteria. The resistance of Klebsiella pneumoniae to imipenem exhibited a significant increase, rising from 21.74% in 2009 to 96.67% in 2018, and subsequently reaching 48.47% in 2021. Acinetobacter baumannii displayed resistance rates exceeding 80.0% against multiple antibiotics. The resistance profile of Pseudomonas aeruginosa was relatively low. The proportion of Staphylococcus aureus reached its peak at 18.70% in 2016, but experienced a decline to 7.83% in 2021. The abundance of Gram-negative bacteria exceeded that of Gram-positive bacteria by a factor of 5.96. Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus are prominent pathogens characterized by limited antibiotic choices and scarce treatment alternatives for the isolated strains.

[Epidemiological Analysis of Carbapenem-Resistant Enterobacteriaceae Strains in the Clinical Specimens of a Hospital].

Objective: To analyze the detection rate, in vitro susceptibility to antibiotics, and carbapenemase types of carbapenem-resistant Enterobacteriaceae (CRE) strains in the clinical samples of a hospital and to provide support for the prevention, control and treatment of CRE-related infections. Methods: Clinical specimens were examined according to the operating procedures of bacteriological tests. Species identification and in vitro drug susceptibility testing were performed on the isolated strains. Carbapenemase inhibitor enhancement testing, which combined the use of 3-aminobenzeneboronic acid and ethylenediaminetetraacetic acid, was conducted to identify the types of carbapenemase in the CRE strains. Results: In 2021, 2215 CRE strains were isolated from 157196 clinical samples collected in this hospital, presenting a detection rate of 1.4% (2215/157196). A total of 1134 non-repetitive strains of CRE were isolated from 903 patients. The main sources of samples were respiratory tract (494/1134, 43.6%), secretion (191/1134, 16.8%) and blood (173/1134, 15.3%) samples. The cases with the same CRE strain isolated from the samples of two, three and four sites accounted for 12.5%, 4.9%, and 1.1%, respectively. The most common species was Klebsiella pneumoniae (883/1134, 77.9%), followed by Enterobacter cloacae complex (107/1134, 9.4%) and Escherichia coli (96/1134, 8.5%). The rates of resistance to polymyxin B and tigecycline of different species of CRE strains were not significantly different ( P<0.05). Serine carbapenemase-producing strains, metallo-ß-lactamase-producing strains, and those producing both enzymes accounted for 82.6% (809/979), 17.2% (168/979), and 0.2% (2/979), respectively. Conclusion: CRE strains are frequently isolated from samples collected from the respiratory tract, secretion, and blood. The most common strain is serine carbapenemase-producing K. pneumoniae, which has a high resistance rate to various antimicrobial drugs, and risk factors of its associated infections deserve more attention.

Prevalence, serotype, and antimicrobial resistance profiles of children infected with Salmonella in Guangzhou, southern China, 2016-2021.

Purpose: Salmonella infection is a key global public health concern and has lead to an increased economic burden on society. We investigated the epidemiological characteristics and antimicrobial resistance profiles of clinically isolated Salmonella strains in Guangzhou Women and Children's Medical Center. Patients and methods: This was a retrospective study of 1,338 Salmonella strains collected from children in Guangzhou Women and Children's Medical Center during 2016 to 2021. Results: The results revealed that 1,338 cases of Salmonella were mainly isolated from feces and blood samples. The age distribution was dominated by infants under 3 years old. The seasonal distribution was high in summer and autumn. 48 serotypes were detected, and S. typhimurium (78.7%) was the predominant serogroup. The results of antimicrobial susceptibility showed that the highest resistance was observed in ampicillin (84.5%), while lower resistance was observed in piperacillin/tazobactam, cefoperazone/sulbactam and ciprofloxacin. The antimicrobial resistance rate of fecal isolates was higher than that of blood isolates. The five-year average detection rate of multi-drug resistant Salmonella was 8.5% (114/1338) and the MDR rate of S. typhimurium was the lowest (6.9%; 73/1053). Conclusion: We concluded that antibacterial treatment should be carefully selected according to serotype and antimicrobial sensitivity results in children. Antimicrobial resistance monitoring for multi-drug resistant Salmonella is still required.

Retrospective Analysis of Epidemiology, Risk Factors, and Outcomes of Health Care-Acquired Carbapenem-Resistant Klebsiella pneumoniae Bacteremia in a Chinese Tertiary Hospital, 2010-2019.

INTRODUCTION: In the present study, we aimed to describe the proportion of carbapenem-resistant Klebsiella pneumoniae bloodstream infection (CRKP-BSI) in KP-BSI in one Chinese tertiary hospital over 10 years and determine the risk factors and outcomes of CRKP-BSI. METHODS: We retrospectively analyzed clinical and microbiological data of patients with KP-BSI from January 2010 to December 2019 to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis. KP-BSI only included monomicrobial BSI and health care-acquired BSI. RESULTS: Among the total 687 isolates of KP-BSI in this study, the rate of CRKP was 39.0% (268/687); this rate in the intensive care unit (ICU) was 65.6% and that in seven high-risk departments (including four ICUs, respiratory medicine, gastroenterology medicine, and hepatobiliary surgery) was 74.6%. The annual rate of CRKP in KP-BSI ranged from 0.0% in 2010 to 54.5% in 2019. The 28-day mortality was 36.2% in patients with CRKP-BSI and 11.7% in those with carbapenem-susceptible K. pneumoniae (CSKP) BSI. Multivariable logistic regression analysis showed that prior ICU stay (odds ratio [OR] 2.485, P < 0.001), hospital stay ≥ 30 days prior to BSI (OR 1.815, P = 0.007), prior mechanical ventilation (OR 2.020, P = 0.014), prior urinary catheter (OR 1.999, P = 0.003), prior carbapenem use (OR 3.840, P < 0.001), hepatobiliary disease (OR 2.943, P < 0.001), pancreatitis (OR 2.700, P = 0.026), and respiratory disease (OR 2.493, P = 0.009) were risk factors of CRKP-BSI. Patients with a first admission (OR 0.662, P = 0.046) had a lower percentage of CRKP-BSI. CONCLUSION: The rapidly rising rate of CRKP-BSI in KP with high mortality requires increased attention. Exposure to carbapenems, ICU stay, invasive mechanical ventilation or urinary catheter, prolonged hospital stay, hepatobiliary disease, pancreatitis, and respiratory disease were found to be risk factors for CRKP-BSI. Strict control measures should be implemented to prevent the emergence and spread of CRKP, especially in high-risk departments.

Analysis of drug resistance and risk factors of multi drug resistant bacteria in bloodstream infection / 中国热带医学

@#Abstract: Objective To analyze the antimicrobial resistance rate and risk factors of multi drug resistant organisms (MDRO) in bloodstream infection for rational treatment. Methods　A total of 696 cases of bloodstream infections of Staphylococcus aureus, Enterococcus, Enterobacteriaceae (excluding Salmonella and Shigella), Pseudomonas aeruginosa and Acinetobacter in our hospital from 2017 to 2021 were selected, and 711 pathogenic strains were isolated from their whole blood samples. The antimicrobial resistance rates of various multi drug resistant strains were analyzed and the risk factors of MDRO infection were analyzed. Results　696 non repeated cases were screened out from 13 187 whole blood culture specimens, with a positive rate of 5.3%, and a total of 711 blood influenza pathogens were detected, among them, 350 strains of MDRO were detected with a detection rate of 49.23% (350/711). Among the pathogenic bacteria of bloodstream infection, Escherichia coli was the most, with 277 strains accounting for 38.96% (277/711), of which 201 strains were MDRO, accounting for 57.43% (201/350); followed by Klebsiella pneumoniae and Staphylococcus aureus, with 155 strains accounting for 21.80% (155/711) and 89 strains accounting for 12.52% (89/711), among which 43 strains of Klebsiella pneumoniae MDRO accounted for 12.29% (43/350) and 38 strains of Staphylococcus aureus MDRO accounted for 10.86% (38/350). The change trend of the three pathogens during 2017-2021 was not obvious. The drug sensitivity test showed that Escherichia coli and Klebsiella pneumoniae were highly resistant to cephalosporins and fluoroquinolones, and the drug resistance rate of aminoglycosides was relatively low. They had almost no resistance to cephalosporins and carbapenems. Staphylococcus aureus has a high resistance rate to lincomycin and macrolides, but no resistance to oxazolidinone, glycopeptides and glycylcyclins. There were 350 cases of MDRO infection and 361 cases of non MDRO infection. Univariate analysis showed that the age, sex, cardiovascular and cerebrovascular history, renal insufficiency, lung disease, hypoalbuminemia, hepatobiliary disease, electrolyte disorder and anemia of the patients had no statistical significance in MDRO infection (P>0.05); diabetes, urinary tract infection, surgical operation and burn were the influencing factors of MDRO (P<0.05). According to logistic analysis, diabetes, urinary tract infection, surgical operation and burn were the risk factors of MDRO infection (P<0.05). Conclusion　The infection of MDRO in patients with bloodstream infection is serious, and early prevention and control should be paid attention to, and the principle of graded use of antibiotics should be strictly observed, and the rational application should be carried out to actively and effectively control the production of MDRO.

Pathogenic characteristics of bloodstream infections in patients with hematological diseases and the impact of stem cell transplantation on them / 中国热带医学

@#Abstract: Objective To investigate the epidemiological characteristics of pathogens causing bloodstream infection in hematology patients during treatment and to compare the effects of allogeneic hematopoietic stem cell transplantation (HSCT) on them, so as to provide evidence for the diagnosis and treatment of bloodstream infection. Methods A total of 292 cases with bloodstream infection in hematology wards of the PLA General Hospital were collected from 2017 to 2021, which were divided into HSCT group and N-HSCT group according to whether performed HSCT or not. The epidemiological characteristics and influence of pathogenic bacteria in blood stream infection were analyzed and compared between the two groups. Results A total of 362 strains of pathogenic bacteria were collected from 292 cases, including 106 strains in HSCT group (84 cases) and 256 strains in N-HSCT group (208 cases). Bloodstream infections were more common in acute myeloid leukemia (130/392, 44.52%), followed by non-Hodgkin's lymphoma (74/292, 25.34%). The rate of once bloodstream infection in HSCT group was higher than that in N-HSCT Group, but the rate of twice bloodstream infections in N-HSCT group was higher. Gram-negative Bacilli were the most common pathogens (56.08%), with Escherichia coli being absolutely dominant (109/362, 30.11%), followed by Klebsiella pneumoniae (39/362, 10.77%). Coagulase-negative staphylococci (CoNS) (107/362, 29.56%) were the most common Gram-positive cocci. The detection rate of fungi in HSCT group (10/106, 9.43%) was significantly higher than that in N-HSCT Group (3.52%). The drug resistance rate of the common pathogenic bacteria was at a high level, and there was a certain proportion of multi-drug resistant strains (except for Pseudomonas aeruginosa). The resistance rates of CoNS to penicillin, gentamicin, moxifloxacin, clindamycin and rifampicin in HSCT group were higher than those in N-HSCT Group. The resistance rate of Escherichia coli to piperacillin/tazobactam, cephalosporins and etapenem in HSCT group was significantly higher than that in N-HSCT group. Conclusions The pathogens of blood stream infection in hematology patients are complicated and various. It is difficult for clinical diagnosis and treatment to detect multiple infections and multiple pathogens. HSCT patients have a higher risk of fungal bloodstream infection and more multi-drug resistant strains detected. Therefore, the identification of bloodstream infection and multi-drug resistant strains associated with HSCT patients should prompt surveillance.

Primary Antibiotic Resistance And Effectiveness Of Clarithromycin Vs Metronidazole Based Therapy For Helicobacter Pylori Infection In Children.

BACKGROUND: NASPGHAN guidelines recommend regional antibiotic susceptibility profiling for H. pylori eradication treatment. Profiling local antibiotic resistance patterns is mandatory for successful H. pylori eradication in children. The aim of our study was to determine primary resistance to Clarithromycin and Metronidazole, most commonly used in the eradication regimens in children presenting with symptomatic H. pylori infection. This study was conducted at Children Hospital PIMS Islamabad from June 2020 to August 2021. METHODS: The children of either gender age 2-14 years having symptomatic H. pylori infection (hematemesis, chronic abdominal pain) underwent stool for H. pylori Antigen. Children requiring urgent diagnostic endoscopy underwent rapid urease tests. Biopsies were taken from children having positive stool H. pylori Ag and rapid urease test for histological examination. The biopsy specimens were cultured and subsequently tested for antibiotic sensitivity. RESULTS: Out of 54 children having H. pylori infection 40/54 (74.074%) children had strains susceptible to antimicrobials and 14/54 (25.92%) were having resistance to antimicrobials. According to the pattern of antimicrobial sensitivity, they were further grouped into three (a) Clarithromycin and Metronidazole sensitive group (18/40, 45%) (b) Clarithromycin sensitive and Metronidazole resistant group (12/40, 30%) (c) Metronidazole sensitive group (10/40 25%). CONCLUSIONS: Clarithromycin and Metronidazole cannot be used as1stline treatment for H. pylori eradication in children and can only be used with known antimicrobial susceptibility.

The influence of gastric atrophy on Helicobacter pylori antibiotics resistance in therapy-naïve patients.

Background: Antibiotic susceptibility of Helicobacter pylori to antibiotics may vary among different niches of the stomach. The progression of chronic H. pylori gastritis to atrophy changes intragastric physiology that may influence selection of resistant strains. Aim: To study the antibiotic resistance of H. pylori taking the severity of atrophic gastritis in antrum and corpus into account. Methods: Helicobacter pylori-positive patients (n = 110, m = 32, mean age 52.6 ± 13.9 years) without prior H. pylori eradication undergoing upper gastrointestinal (GI) endoscopy for dyspeptic symptoms were included in a prospective study. Patients were stratified into three groups depending on the grade of atrophy: no atrophy (OLGA Stage 0), mild atrophy (OLGA Stage I-II) and moderate/severe atrophy (OLGA Stage III-IV). Two biopsies each from the antrum and the corpus and one from the angulus were taken and assessed according to the updated Sydney system. H. pylori strains were isolated from antrum and corpus biopsies and tested for antibiotic susceptibility (AST) for amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and rifampicin by the agar dilution methods. A Chi-square test of independence with a 95% confidence interval was used to detect differences in the proportion of patients with susceptible and resistant H. pylori strains. Results: Among 110 patients, primary clarithromycin resistance (R) was 30.0%, both in the antrum and corpus; metronidazole resistance accounted for 36.4 and 34.5% in the antrum and corpus; and levofloxacin was 19.1 and 22.7% in the antrum and corpus, respectively. Resistance rates to amoxicillin, tetracycline, and rifampicin were below 5%. Dual antibiotic resistance rate was 21.8%, and triple resistance rate was 9.1%. There was a significant difference in the resistance rate distribution in antrum (p < 0.0001) and corpus (p < 0.0001). With increasing severity of atrophy according to OLGA stages, there was a significant increase in clarithromycin-R and metronidazole-R. Conclusion: In treatment-naïve patients, antibiotic resistance and heteroresistance were related to the severity of atrophy. The high clarithromycin resistance in atrophic gastritis suggests that H. pylori antibiotic susceptibility testing should always be performed in this condition before selecting the eradication regimen.

The Use of Antibiotics for Ventilator-Associated Pneumonia in the MIMIC-IV Database.

Purpose: By analyzing the clinical characteristics, etiological characteristics and commonly used antibiotics of patients with ventilator-associated pneumonia (VAP) in intensive care units (ICUs) in the intensive care database. This study aims to provide guidance information for the clinical rational use of drugs for patients with VAP. Method: Patients with VAP information were collected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, including their sociodemographic characteristics, vital signs, laboratory measurements, complications, microbiology, and antibiotic use. After data processing, the characteristics of the medications used by patients with VAP in ICUs were described using statistical graphs and tables, and experiences were summarized and the reasons were analyzed. Results: This study included 2,068 patients with VAP. Forty-eight patient characteristics, including demographic indicators, vital signs, biochemical indicators, scores, and comorbidities, were compared between the survival and death groups of VAP patients. Cephalosporins and vancomycin were the most commonly used. Among them, fourth-generation cephalosporin (ForGC) combined with vancomycin was used the most, by 540 patients. First-generati49n cephalosporin (FirGC) combined with vancomycin was associated with the highest survival rate (86.7%). More than 55% of patients were infected with Gram-negative bacteria. However, patients with VAP had fewer resistant strains (<25%). FirGC or ForGC combined with vancomycin had many inflammation-related features that differed significantly from those in patients who did not receive medication. Conclusion: Understanding antibiotic use, pathogenic bacteria compositions, and the drug resistance rates of patients with VAP can help prevent the occurrence of diseases, contain infections as soon as possible, and promote the recovery of patients.

Establishment of Epidemiological Resistance Cut-Off Values of Aquatic Aeromonas to Eight Antimicrobial Agents.

The abuse of antibiotics in aquaculture has led to the increasing rate of antibiotic resistance of aquatic bacteria including Aeromonas, which is an increasing threat to environmental and human health. To date, no epidemiological cut-off values (COWT) for Aeromonas spp. have been established by the Clinical and Laboratory Standards Institute nor the European Commission on Antimicrobial Susceptibility Testing. In this study, commercially prepared minimum inhibitory concentration (MIC) test 96-well plates (dry-form plates) were used to determine the MIC of eight antimicrobial agents against 556 Aeromonas strains. The obtained MIC distributions were simulated and analyzed by NRI and ECOFFinder to obtain tentative COWT values for Aeromonas spp. The COWT values of eight kinds of representative antimicrobial agents including trimethoprim-sulfamethoxazole, erythromycin, doxycycline, neomycin, colistin, florfenicol, enrofloxacin, and ceftazidime for Aeromonas spp. were established and were 0.25, 64/32, 4/2, 8, 4, 1, 0.062/0.125, and 0.5 µg/mL, respectively. Results showed that Aeromonas spp. had a very high proportion of non-wild-type strains to enrofloxacin, florfenicol, and doxycycline, which are the most widely used antimicrobials in aquaculture. The COWT values for Aeromonas spp. obtained in this study can contribute to the final establishment of COWT for Aeromonas spp. internationally.

Impact of carbapenem-resistant Acinetobacter baumannii infections on acute pancreatitis patients.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) infections present great challenges in clinical practices with high mortality. The aim of this study is to identify the impact of CRAB infections on acute pancreatitis (AP). METHODS: A case-control study was performed via collecting data from March 1st, 2016 to August 1st, 2020 in two comprehensive teaching hospital. Clinical data of the CRAB-positive AP patients were analyzed and compared to a matched control group (case-control ratio of 1:1). Comparisons were preformed between with/without CRAB infections and multiple organ failure (MOF), respectively. Independent risk factors of overall mortality were determined via univariate and multivariate analyses. RESULTS: CRAB infections were associated with higher mortality (49.2% vs. 23.0%, P < 0.01). CRAB combined with MOF increased a mortality up to 90% (P < 0.01). MOF (Odds ratio (OR) = 21.49, 95% confidence interval (CI) = 5.26-87.80, P < 0.01), CRAB infections (OR = 3.58, 95%CI = 1.24-10.37, P = 0.02) and hemorrhage (OR = 3.70, 95%CI = 1.21-11.28, P = 0.02) were independent risk factors of overall mortality. Lung was the most common site of strains (37 of 82). CRAB strains were highly resistant (>60%) to ten of eleven common antibiotics, except for tigecycline (28%). CONCLUSION: High mortality rate in AP patients was associated with CRAB infections and further increased when CRAB infections combined with MOF.

Analysis of bacterial distribution and antibiotic resistance in children with severe pneumonia through bronchoalveolar lavage fluid / 中国小儿急救医学

Objective:To realize the bacterial distribution and antibiotic resistance in children with severe pneumonia in this region.Methods:A total of 203 children with severe pneumonia diagnosed in Gansu Provincial People′s Hospital from April 2018 to March 2020 were divided into 0-1, 1-3, 3-7 and 7-14 years old groups.Bronchoalveolar lavage fluid was collected for bacterial culture and identification, and antibiotic susceptibility tests were performed.Results:The positive rate of pathogens was 69.5% (141/203), including 72.3% (102 strains) of Gram-negative bacteria and 30.5%(43 strains)of Gram-positive bacteria.The infection rates were highest in 0-1 years old group and the lowest in 7-14 years old group, which were 45.2%(19/42) and 16.9%(10/59), respectively.The infection rates of Haemophilus influenzae, Escherichia coli and Branhamella catarrhalis in the 1-3 years old group were 30.30%(10/33), 33.33% (11/33), and 21.21% (7/33), respectively, which showed significant differences compared with other groups( P<0.05). The infection rate of Streptococcus pneumoniae in the 0-1 years old group was 42.9%(18/42), which was significantly different compared with other groups ( P<0.001). The resistance rate of Haemophilus influenzae to trimethoprim/sulfamethoxazole was 89.5%(34/38), and the Streptococcus pneumoniae to trimethoprim/sulfamethoxazole and tetracycline were both 82.4%(28/34). The highest antibiotic resistance rate of Escherichia coli was 34.6%(9/26), and the Branhamella catarrhalis to clindamycin was 56.3%(9/16). Conclusion:The dominant bacteria for severe pneumonia in children are Haemophilus influenzae, Streptococcus pneumoniae, Escherichia coli and Branhamella catarrhalis.The bacterial infection rate is highest within 1 year old, but gradually decreases with the increase of age.Haemophilus influenzae and Streptococcus pneumoniae have severe resistance to several antibiotics.

Resistance Trend Estimation Using Regression Analysis to Enhance Antimicrobial Surveillance: A Multi-Centre Study in London 2009-2016.

In the last years, there has been an increase of antimicrobial resistance rates around the world with the misuse and overuse of antimicrobials as one of the main leading drivers. In response to this threat, a variety of initiatives have arisen to promote the efficient use of antimicrobials. These initiatives rely on antimicrobial surveillance systems to promote appropriate prescription practices and are provided by national or global health care institutions with limited consideration of the variations within hospitals. As a consequence, physicians' adherence to these generic guidelines is still limited. To fill this gap, this work presents an automated approach to performing local antimicrobial surveillance from microbiology data. Moreover, in addition to the commonly reported resistance rates, this work estimates secular resistance trends through regression analysis to provide a single value that effectively communicates the resistance trend to a wider audience. The methods considered for trend estimation were ordinary least squares regression, weighted least squares regression with weights inversely proportional to the number of microbiology records available and autoregressive integrated moving average. Among these, weighted least squares regression was found to be the most robust against changes in the granularity of the time series and presented the best performance. To validate the results, three case studies have been thoroughly compared with the existing literature: (i) Escherichia coli in urine cultures; (ii) Escherichia coli in blood cultures; and (iii) Staphylococcus aureus in wound cultures. The benefits of providing local rather than general antimicrobial surveillance data of a higher quality is two fold. Firstly, it has the potential to stimulate engagement among physicians to strengthen their knowledge and awareness on antimicrobial resistance which might encourage prescribers to change their prescription habits more willingly. Moreover, it provides fundamental knowledge to the wide range of stakeholders to revise and potentially tailor existing guidelines to the specific needs of each hospital.

Healthcare-associated blood stream infections in hematological patients in Finland during the years 2006-2016.

OBJECTIVES: The aim was to identify the clinical characteristics, outcome, and antimicrobial susceptibility of healthcare-associated bloodstream infections (BSIs) in hematological patients. METHODS: This retrospectively collected laboratory-based surveillance data include 3404 healthcare-associated BSIs in 2296 patients with a hematological malignancy in hospitals participating in the Finnish Hospital Infection Program from January 1, 2006, to December 31, 2016. RESULTS: The most common underlying diseases were acute myelogenous leukemia (35%) and non-Hodgkin lymphoma (22%). Gram-positive organisms accounted for 60%-46% and gram-negative organisms for 24%-36% of BSIs in 2006-2016. The most common causative organism was coagulase-negative staphylococci (CoNS) (n = 731). The 7- and 28-day case fatality rates were 5.2% and 11.4%, respectively, and was highest in BSIs caused by Candida species (10.8% and 30.8%). The median age of patients increased from 59 years in 2006-2008 to 62 years in 2015-2016 (P < .01). Five percent of S aureus isolates were resistant to methicillin and five percent of Pseudomonas aeruginosa isolates were multidrug-resistant. Four percent of Klebsiella and seven percent of E coli isolates were resistant to ceftazidime. CONCLUSIONS: The proportion of gram-positive bacteria decreased and gram-negative bacteria increased over time. The case fatality rate was low and the median age of patients increased during the study.

Multidrug resistance: The clinical dilemma of refractory Helicobacter pylori infection.

This study investigated the antimicrobial resistance of isolates from patients with refractory Helicobacter pylori. The resistance rate was 34.1% for amoxicillin, 92.7% for clarithromycin, 65.9% for metronidazole, 85.4% for levofloxacin, and 29.3% for rifabutin. Dual resistance to both clarithromycin and levofloxacin was found in 73.2%. The antimicrobial resistance rate of refractory H. pylori was extremely high, which had become a major consideration in therapeutic challenge.

Epidemiology, Susceptibility, and Risk Factors Associated with Mortality in Carbapenem-Resistant Gram-Negative Bacterial Infections Among Abdominal Solid Organ Transplant Recipients: A Retrospective Cohort Study.

INTRODUCTION: Carbapenem-resistant gram-negative bacteria (CR-GNB) can cause life-threatening infections among abdominal solid organ transplantation (ASOT) recipients. This study aimed to investigate the epidemiology and drug susceptibility of CR-GNB pathogens and identity the risk factors associated with 90-day crude mortality of CR-GNB infections among ASOT recipients. METHODS: We retrospectively reviewed the clinical characteristics, drug resistance rate, and risk factors associated with mortality in CR-GNB infections among ASOT recipients between August 1, 2013, and August 1, 2020. The Cox regression model was performed to identify the independent risk factors for mortality. RESULTS: During the 8-year period, CR-GNB infections occurred in 153 of 1452 (10.5%) recipients, and 23 of 153 (15.0%) patients died. The most common pathogen was Acinetobacter baumannii (n = 47). The drug resistance rate of CR-GNB pathogens was relatively low to tigecycline (33.3%) and high to other categories (> 60%). There was a significant increasing trend in drug resistance to tigecycline as time went on (from 24 to 40%, P = 0.04). The independent risk factors for mortality were mechanical ventilation (hazard ratio 7.40, 95% confidence interval 2.69-20.38, P < 0.001), septic shock (hazard ratio 7.41, 95% confidence interval 2.86-19.23, P < 0.001), and platelet count < 50,000/mm3 (hazard ratio 4.00, 95% confidence interval 1.49-10.76, P = 0.006). CONCLUSION: CR-GNB is widespread with high prevalence and mortality rates among ASOT recipients. Mechanical ventilation, septic shock, and low platelet count represent three independent risk factors related to the mortality of ASOT recipients with CR-GNB infection. We suggest that tigecycline may be used under rigorous management because of the significant increasing risk of drug resistance.

[Pathogens' distribution and changes of antimicrobial resistance in the bile of acute biliary tract infection patients].

Objective: To investigate the pathogens' distribution and antimicrobial resistance in the bile of acute biliary tract infection patients. Methods: The data of bile bacterial culture and drug sensitivity test of 223 acute biliary tract infection patients who underwent gallbladder puncture or endoscopic retrograde cholangiopancreatography drainage from July 2009 to July 2019 were analyzed retrospectively at Department of General Surgery,Xinhua Hospital,Affiliated to Shanghai Jiao Tong University School of Medicine.There were 141 males and 82 females with age of 67.3 years(range:28 to 93 years).Three to five milliliter of bile was extracted from each patient and sent to the laboratory for bacterial culture,identification and drug sensitivity test.The patients were divided into two groups according to the visiting time: the former group (n=124) was admitted from July 2009 to July 2014,and the latter group(n=99) was admitted from August 2014 to July 2019.The distribution of pathogenic bacteria and the changing trend of drug resistance rate of common bacteria in the two groups were compared.The results of drug sensitivity test were analyzed by WHONET software provided by WHO bacterial surveillance network.The drug resistance rates in different time periods were compared by χ2 test. Results: In this study,there were 147 cases of acute cholangitis and 76 cases of acute cholecystitis.A total of 376 strains of pathogenic bacteria were cultured.Among them,98 strains(26.1%) were gram-positive bacteria,269 strains(71.5%) were gram-negative bacteria and 9 strains(2.4%) were fungi.The top three gram-positive bacteria were Enterococcus faecium (49.0%,48/98),Enterococcus faecalis(20.4%,20/98),and Enterococcus luteus(7.1%,7/98).The top 5 gram-negative bacteria were Escherichia coli(33.5%,90/269),Klebsiella pneumoniae(13.8%,37/269),Pseudomonas aeruginosa(13.0%,35/269),Acinetobacter baumannii (12.6%,34/269),and Enterobacter cloacae(4.8%,13/269).From 2009 to 2019,there was no significant change in the proportion of gram-positive bacteria (former group vs. latter group: 25.3% vs. 28.2%) and gram-negative bacteria(former group vs.latter group: 74.7% vs. 71.8%) in the bile of patients with acute biliary tract infection.Gram-positive bacteria were mainly Enterococci(85.7%,84/98) and gram-negative bacteria were Escherichia coli(33.5%,90/269).Acinetobacter baumannii accounted for 7.8%(11/142) of gram-negative bacteria in the former group and 18.1%(23/127) in the latter group,an increase of 10.3% over previous five years.Pseudomonas aeruginosa had a downward trend,16.9% in the former group(24/142) and 8.7% in the latter group (11/127),the proportion decreased by 8.2%,and the other changes were not significant.The drug resistance rates of common gram-positive bacteria were relatively stable,and the drug resistance rates of Enterococcus faecium to many antibiotics were higher than those of Enterococcus faecalis.The resistance rates of gram-negative bacteria to most antibiotics showed an upward trend,among which Klebsiella pneumoniae showed an upward trend to most of antibiotics(former group: 0/15－4/13, latter group: 55.0%－70.0%; χ2=3.996－16.942, P=0.000－0.046).The drug resistance rates of Acinetobacter baumannii was generally higher,but there were no significant changes in the drug resistance rates of Acinetobacter baumannii between the two groups.The drug resistance rates of Pseudomonas aeruginosa to most antibiotics increased,and the overall drug resistance rates of Escherichia coli were stable and showed a slight upward trend. Conclusions: The main pathogens in bile of patients with acute biliary tract infection are gram-negative bacteria.The constituent ratio of various gram-negative bacteria had no significant change from 2009 to 2019,but the drug resistance rates shows an upward trend.Among the gram-negative bacteria, Escherichia coli is the most important pathogen,and the proportion has no significant change.The proportion of Acinetobacter baumannii in the former group was significantly higher than that in the former group.And the proportion of Pseudomonas aeruginosa has a decreased trend.

Monitoring antimicrobial cross-resistance with cross-resistance rate correlation diagrams: Changes in antibiotic susceptibility of Pseudomonas aeruginosa due to hospital relocation.

WHAT IS KNOWN AND OBJECTIVE: Though most medical institutions calculate antimicrobial susceptibility and resistance rates of microbes isolated at their own facility as part of their efforts to promote the proper use of antibiotics, very few, if any, regularly monitor cross-resistance rates between antimicrobial agents. The authors have devised a tool in the form of a cross-resistance rate correlation diagram (CRR diagram) that allows easy identification of increases or decreases in, or changes in the pattern of, antimicrobial cross-resistance. The objective was to perform an analysis by CRR diagrams of the effect of relocation to a newly built facility on antimicrobial resistance and cross-resistance rates at a medical facility. METHODS: The Sakai City Medical Center relocated in July 2015 to a newly built facility located in a different primary medical care zone 3.5 km away. Based on the drug susceptibility test data compiled at the Sakai City Medical Center, resistance and cross-resistance rates of Pseudomonas aeruginosa before and after the relocation of the hospital facility were calculated, and the rates were assessed using CRR diagrams. RESULTS AND DISCUSSION: It was possible to confirm the effect of hospital relocation on antibiotic susceptibility of P aeruginosa in terms of changes in resistance and cross-resistance rates. The effect of the facility's relocation on cross-resistance rates was particularly notable with respect to ß-lactam antibiotics: cross-resistance rates among ß-lactams decreased substantially, represented as a large wedge-shaped change towards the origin on the CRR diagram. Rates of cross-resistance between classes of antibiotics with a different mechanism of antibiotic action changed little. WHAT IS NEW AND CONCLUSION: Including cross-resistance rates in the routine monitoring of resistance and susceptibility rates practiced by a medical institution can provide a comprehensive insight into the dynamics of bacterial flora in the facility. CRR diagrams, which allow visualization of the status and changes in cross-resistance, not only provide a new perspective for clinicians, but they also contribute to the proper use of antibiotics and serve as a tool in the education of healthcare professionals and students about antibiotic resistance.