MLSA phylogeny and antimicrobial susceptibility of clinical Nocardia isolates: a multicenter retrospective study in China

Abstract Background With the increase of detection rate and long treatment period, nocardiosis has become a noticeable problem in China. However, there are limited large-scale studies on the epidemiology and antimicrobial susceptibility profiles of clinical Nocardia spp. in China. The present study aimed to explore the species distribution and drug susceptibility pattern of 82 clinical Nocardia isolates from three tertiary hospitals in China by multilocus sequence analysis (MLSA) and broth microdilution (BMD) method. Results Pulmonary nocardiosis (90.2%) was the most common clinical presentation of infection. N. cyriacigeorgica (n = 33; 40.2%) and N. farcinica (n = 20; 24.4%) were the most frequently encountered Nocardia species, followed by N. otitidiscaviarum (n = 7; 8.5%), N. abscessus (n = 5; 6.1%), N. asiatica (n = 4; 4.9%), and N. wallacei (n = 4; 4.9%). Trimethoprim/sulfamethoxazole (SXT) remained high activity against all Nocardia isolates (susceptibility rate: 98.8%). Linezolid and amikacin were also highly active; 100 and 95.1% of all isolates demonstrated susceptibility, respectively. Except for N. otitidiscaviarum, all the Nocardia isolates exhibited high susceptibility rates to imipenem. The resistance rates of all isolates to clarithromycin and ciprofloxacin were 92.7 and 73.2%, respectively, but the resistance rate of N. farcinica to ciprofloxacin was only 25%. Conclusions The clinically isolated Nocardia spp. had diverse antimicrobial susceptibility patterns, which were similar to the reports by other groups elsewhere, but some differences were also observed, mainly including imipenem and ciprofloxacin. According to this study, SXT still can be the first choice for empirical therapy due to the low resistance rate. Linezolid can be chosen when a patient is allergic to SXT, and amikacin and imipenem can be the choice in a combination regimen.

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Antimicrobial resistance of Klebsiella Pneumoniae Pathogens in 2019 of Shaoxing City, Zhejiang Province: A Multi-Centre, Retrospective Study

10.21203/rs.3.rs-132287/v1 ◽

2020 ◽

Author(s):

Meichun Liang ◽

Guofeng Mao ◽

Xiaojiao Zhang ◽

Qiuli He ◽

Qunhua Ying ◽

...

Keyword(s):

Health Care ◽

Drug Resistance ◽

Child Health ◽

Drug Susceptibility ◽

Resistance Rate ◽

Child Health Care ◽

Care Hospital ◽

Tertiary Hospitals ◽

Resistance Rates ◽

And Child Health

Abstract Background: The detection rate and drug resistance rate of K. pneumoniae increased year by year in China. Understanding the drug resistance situation will help guide prevention and control of K. pneumoniae infection. Methods: This study collected the results of drug susceptibility of K. pneumoniae from six tertiary hospitals in Shaoxing city in 2019 and analyzed the differences in drug resistance among different hospitals, genders, ages, and specimens. Results: A total of 1954 strains were collected, all of which were most sensitive to amikacin, with a resistance rate of 4.42%. The resistance rate to carbapenems and tigecycline was less than 10%. Nitrofurantoin had the highest resistance rate (36.18%). The drug resistance rate of Shaoxing traditional Chinese medicine hospital and Shaoxing maternity and child health care hospital was lower, and the drug resistance rate of the affiliated hospital of Shaoxing University was the highest. In addition to the Shaoxing maternity and child health care hospital, specimens were mainly from elderly and male patients, the drug resistance rate increased with age, and no carbapenem-resistant strains were found in patients under 17 years old. The specimens were mostly from the respiratory tract and urinary tract, but the CRKP rate was the highest in blood, the ESBL rate was the highest in other sterile body fluids except for blood, and the high ESBL and CR rates in urine were also detected. Conclusions: The above results indicated that there were significant differences in drug resistance rates of strains among different hospitals, genders, ages, and specimen sources, and clinical empirical medication should be incorporated into the reference.

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Invasive isolates of Streptococcus pneumoniae in Serbia: Antimicrobial susceptibility and serotypes

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh1302048g ◽

2013 ◽

Vol 141 (1-2) ◽

pp. 48-53 ◽

Cited By ~ 2

Author(s):

Ina Gajic ◽

Vera Mijac ◽

Lazar Ranin ◽

Dragana Andjelkovic ◽

Miroslava Radicevic ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Invasive Pneumococcal Disease ◽

Antimicrobial Susceptibility ◽

Pneumococcal Disease ◽

Medical Problem ◽

Resistance Rate ◽

Reference Laboratory ◽

Susceptibility Pattern ◽

Antimicrobial Susceptibility Pattern ◽

Resistance Rates

Introduction. Streptococcus pneumoniae is one of the leading causes of bacterial meningitis and sepsis. Invasive pneumococcal disease is a significant medical problem worldwide, particularly in children, due to a huge increase of pneumococcal resistance to antibiotics. Objective. The aim of the study was to investigate the antimicrobial susceptibility pattern of invasive pneumococcal isolates, as well as to determine whether decreased S. pneumoniae susceptibility to antibiotics was related to a particular serotype. Methods. Antimicrobial susceptibility to 19 antibiotics was determined in 58 invasive pneumococcal strains that were collected from seven regional centers during the period July 2009 to February 2011 in the National Reference Laboratory for streptococci and pneumococci. Results. The overall nonsusceptibility rate to penicillin was detected in 34% of pneumococcal isolates and to erythromycin in 36%. Higher resistance rates were observed among children than among adults. Penicillin resistance rate was 65% in children versus 22% in adults, while erythromycin nonsusceptibility rate was 47% in children versus 32% in adults. Co-resistance to penicillin and erythromycin was detected in 21% strains, mostly isolated from children. Multiresistance was found in one third of isolates. All strains were susceptible to vancomycin, linezolid, fluoroquinolones, telithromycin and rifampicin, while 23 (40%) isolates were susceptible to all tested antibiotics. The most common resistant serotypes were 19F and 14. Conclusion. The study has revealed that penicillin and macrolide resistance among invasive pneumococcal isolates is very high in Serbia. This emphasizes the need for continuous monitoring for invasive pneumococcal disease to document the serotype distribution and antimicrobial susceptibility pattern.

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Antimicrobial susceptibility of Pasteurella multocida isolated from sheep and pigs in Spain – Short communication

Acta Veterinaria Hungarica ◽

10.1556/004.2019.048 ◽

2019 ◽

Vol 67 (4) ◽

pp. 489-498

Author(s):

Dolores Cid ◽

José Francisco Fernández-Garayzábal ◽

Chris Pinto ◽

Lucas Domínguez ◽

Ana Isabel Vela

Keyword(s):

High Resistance ◽

Antimicrobial Susceptibility ◽

Pasteurella Multocida ◽

Antimicrobial Agents ◽

Empirical Therapy ◽

Microdilution Method ◽

Low Levels ◽

Resistance Rates ◽

Farming Industry ◽

Susceptibility Patterns

Pasteurella multocida is responsible for economically important diseases in sheep and pigs. Antimicrobial susceptibility studies are essential for initiating rational and effective empirical therapy of P. multocida infections. In this study we investigated the antimicrobial susceptibility to 18 antimicrobial agents of 156 clinical isolates of P. multocida from sheep (n = 87) and pigs (n = 69) using the microdilution method. Both sheep and pig isolates exhibited low levels of resistance (≤ 15%) to ceftiofur, gentamicin, neomycin, spectinomycin, chlortetracycline, tulathromycin, florfenicol, danofloxacin, and enrofloxacin and trimethoprim/sulphamethoxazole, high resistance rates (> 15% up to 50%) to oxytetracycline, tilmicosin, and tiamulin, and very high resistance rates (> 50%) to tylosin tartrate, clindamycin, and sulphadimethoxine. However, sheep isolates exhibited significantly lower percentages of resistance and lower MIC90 values (P < 0.05) than pig isolates for most of the antimicrobials tested. In addition, sheep isolates exhibited also significantly lower phenotypic antimicrobial resistance diversity (8 resistotypes vs. 30 resistotypes). LAC-LIN-SUL-MAC was the resistotype most frequently detected in sheep (39.1%) and LIN-SUL-MAC in pig isolates (26.1%). The differences in susceptibility patterns could be influenced by the lower use of antimicrobials in the small ruminant industry compared with the pig farming industry.

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Antibiotic resistance rate of the Methicillin Resistant Staphylococcus aureus isolated from a university affiliated hospital in North Cyprus

Bangladesh Journal of Medical Science ◽

10.3329/bjms.v21i1.56334 ◽

2022 ◽

Vol 21 (1) ◽

pp. 101-104

Author(s):

Hussein Ahmad ◽

Meryem Guvenir ◽

Emrah Guler ◽

Ayse Arikan ◽

Kaya Suer

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Bacterial Resistance ◽

Medical Science ◽

Resistance Rate ◽

Preventative Measures ◽

North Cyprus ◽

Chest Disease ◽

Mrsa Strains ◽

Resistance Rates

Background: Over the past 20 years, studies have indicated that the increasing spread of methicillinresistant Staphylococcus aureus (MRSA) demonstrates the need for adequate information about their epidemiology. This study was conducted in order to investigate the resistance rate of MRSA which were isolated from the Near East University (NEU) Hospital, North Cyprus. Methods: MRSA was isolated and identified by using selective media and the Phoenix BD 100 system (software version 6.01A) was used for antimicrobial susceptibility testing and identification. The antimicrobial susceptibility results were determined according to the Clinical and Laboratory Standarts Institute (CLSI) and the resistance rates of MRSA isolates to antibiotics were examined retrospectively. Results: The highest number of samples were from the departments of chest disease (24%) followed by dermatology (21.3%) and cardiology (18.7%). Out of 75 MRSA strains,; 29.7% from blood, 25.3% from wound, 14.7% from nasal swabs, 10.7% from aspiration fluids, 9.3% from sputum, 6.7% were from urine, 4.0% from IV catheters culture samples. All strains of MRSA were 94.7% sensitive to vancomycin and teicoplanin. Conclusions: The obtained results revealed that preventative measures should be implemented in order to minimize the bacterial resistance to antibiotics. Bangladesh Journal of Medical Science Vol. 21(1) 2022 Page : 101-104

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Prevalence, resistance, and extended-spectrum beta-lactamases among Salmonella from patients in northeast China

The Journal of Infection in Developing Countries ◽

10.3855/jidc.9218 ◽

2017 ◽

Vol 11 (06) ◽

pp. 470

Author(s):

Zhijie Zhang ◽

Xingning Wang ◽

Ruihua Li ◽

Wencheng Xue ◽

Rubo Zhai ◽

...

Keyword(s):

Resistance Rate ◽

Liaoning Province ◽

First Line ◽

Beta Lactamases ◽

Extended Spectrum ◽

First Choice ◽

Genes Encoding ◽

Extended Spectrum Beta Lactamases ◽

Agar Dilution ◽

Resistance Rates

Introduction: Salmonella is an important infection in Liaoning Province. Serotype and resistance levels are poorly studied. Knowledge of cephalosporin-resistant genes is needed to provide information to support the clinical diagnosis and to guide therapy. Methodology: A total of 172 isolates were collected from January 2009 to March 2014. Resistance to cephalosporin, fluoroquinolones, and other conventional first-line antibiotics was detected using the disk diffusion and agar dilution methods. The relatedness of isolates with the same serotype was analyzed by pulsed-field gel electrophoresis (PFGE). Genes encoding extended-spectrum β-lactamase enzymes (blaCTX-M, blaTEM, blaSHV, and blaOXA) were identified by polymerase chain reaction (PCR) and sequencing in cephalosporin-resistant strains. Results: S. Enteritidis, 1,4,[5],12:i:-, and S .Typhimurium were the most common serotypes. The resistance rate of Salmonella to conventional first-line antibiotics sulfamethoxazole-trimethoprim, tetracycline, chloramphenicol, and ampicillin was 21%,33%,37%, and 55%,respectively. To fluoroquinolones (gatixacin, levofloxacin, and ciprofloxacin), the resistance rates were 7%,18%, and 23%, respectively, whereas for extended-spectrum cephalosporins(ceftazidime, cefepime, and ceftriaxone), there sistance rates were 4%,8%, and 9%. In total, 14blaCTX-M, 14 blaTEM-1, and 1blaOXA-1 were found in 15 Salmonella isolates resistant to cephalosporin. No blaSHVwas detected. The blaCTX-M-55 gene was the most frequently encountered gene. The blaCTX-M-65 gene from S. Enteritidis is described for first time in Salmonella from humans. Results of PFGE indicated strong similarity among Salmonella isolates in Liaoning Province. Conclusions: Extended-spectrum cephalosporins are the first choice for the treatment of infection with Salmonella, but blaCTX-M-encoded resistance, including blaCTX-M-65, is present.

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Occurrence and Characterization of Salmonella Isolated from Large-Scale Breeder Farms in Shandong Province, China

BioMed Research International ◽

10.1155/2019/8159567 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Jie Yang ◽

Siwei Gao ◽

Yajie Chang ◽

Mingliu Su ◽

Yutong Xie ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Resistance Genes ◽

Antimicrobial Susceptibility ◽

Multilocus Sequence Typing ◽

Large Scale ◽

Shandong Province ◽

Sequence Type ◽

Class 1 ◽

Resistance Rates

This study aimed to investigate the prevalence and antimicrobial resistance of Salmonella spp. isolated from large-scale breeder farms in Shandong Province, China. A total of 63 Salmonella isolates (63/409, 15.4%) were identified from 409 samples collected from five large-scale breeder farms in Shandong Province. These Salmonella isolates were assayed for serotype, antimicrobial susceptibility, prevalence of class 1 integrons, quinolone resistance genes, and β-lactamase genes and subtyped by multilocus sequence typing (MLST). Among these isolates, S. Enteritidis (100%) was the predominant serovar, and high antimicrobial resistance rates to nalidixic acid (100.0%), streptomycin (100.0%), ampicillin (98.4%), and erythromycin (93.7%) were observed. All of the isolates carried blaTEM. MLST results showed that only one sequence type (ST11) was identified. Our findings indicated that Salmonella was generally prevalent not only on broiler farms but also on breeder farms.

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Five years prospective survey of antibiotic resistance in Bacteroides and Parabacteroides isolated from inpatients of clinical hospital in Warsaw, Poland

Medycyna Doświadczalna i Mikrobiologia ◽

10.32394/mdm.72.02 ◽

2020 ◽

pp. 13-19

Keyword(s):

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Bacterial Infections ◽

Anaerobic Bacteria ◽

Empirical Therapy ◽

Drug Susceptibility ◽

Clinical Isolates ◽

Patient Treatment ◽

Antimicrobial Susceptibility Tests ◽

Susceptibility Tests

Objectives: Diagnostics of anaerobic bacterial infections and determination of drug susceptibility are technically difficult and time-consuming; therefore, the number of studies on Anaerobic Gram-negative bacilli is significantly limited, especially in Europe. The aim of the study was to analyze the antibiotic susceptibility of clinically important anaerobic bacteria Bacteroides spp. and Parabacteroides distasonis. Strains were isolated from infections of patients hospitalized at one Polish hospital as a result of routine microbiological diagnostics. Material and methods: Clinical isolates were identified with MALDI-TOF MS. Antimicrobial susceptibility of 276 strains was carried out by E-test gradient strip to commonly used antibiotics i.e. benzylpenicillin, amoxicillin with clavulanic acid, imipenem, clindamycin and metronidazole. MIC values were determined. The interpretation of antimicrobial susceptibility tests were conducted in accordance with The European Committee on Antimicrobial Susceptibility Testing (EUCAST) recommendations. Results: Susceptibility tests of all isolates yielded the following rates of resistance to the evaluated β-lactam antibiotics: benzylpenicillin (96%), amoxicillin/clavulanic acid (7.6%), imipenem (2.1%). In presented study 38.8% of clindamycin-resistant strains were isolated, among them 18.3% of B. fragilis and 53.85% P. distasonis. All strain were susceptible to metronidazole. Conclusions: Obtained results and analysis of the results of other researchers convinces us that it is necessary to routinely or at least periodically monitor drug susceptibility of clinical isolates of anaerobic bacteria and use targeted therapy based on the result of the antibiogram. Although high percentage of the tested Bacteroides and Parabacteroides strains remained susceptible to metronidazole and β-lactam antibiotics the use of clindamycin in empirical therapy may not be efficacious. Antibiogram results should be consult with the staff responsible for patient treatment and hospital antibiotic policies.

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Drug-sensitivity test and analysis of drug-resistant mutations in Mycobacterium tuberculosis isolates from Kashgar, China

European Journal of Inflammation ◽

10.1177/20587392211041437 ◽

2021 ◽

Vol 19 ◽

pp. 205873922110414

Author(s):

Zhongchen Ma ◽

Tianhao Sun ◽

Xinyu Bai ◽

Xiang Ji ◽

Qian Zhang ◽

...

Keyword(s):

Drug Resistance ◽

Mycobacterium Tuberculosis ◽

Dna Sequencing ◽

High Sensitivity ◽

Drug Susceptibility ◽

Resistance Rate ◽

Clinical Isolates ◽

Multi Drug Resistance ◽

Drug Resistant ◽

Resistance Rates

Introduction In recent years, drug-resistant Mycobacterium tuberculosis strains have gradually become widespread. Most drug resistance is related to specific mutations. We investigated M. tuberculosis drug resistance in the Kashgar area, China. Methods The drug-susceptibility test was conducted to clinical isolates of M. tuberculosis. Genomic-sequencing technology was used for the drug-resistant strains and the significance of DNA sequencing as a rapid aid for drug-resistance detection and the diagnosis method was evaluated. Results The resistance rates of clinical isolates to rifampicin (RFP), isoniazid (INH), streptomycin (SM), ethambutol (EMB), and ofloxacin (OFX) were, respectively, 4.4%, 12.3%, 8.8%, 2.6%, and 3.5%. The single- and multi-drug resistance rates were, respectively, 80.0% and 20.0%. The resistance genes RopB, katG, InhA, RpsL, rrs, gyrA, and embB displayed codon mutations, while InhA was mutated in its promoter region. Kappa scores, evaluating the consistency between DNA sequencing and the resistance ratio methods for the detection of isolates’ resistance to RFP, INH, SM, OFX, and EMB, were 1, 0.955, 0.721, 0.796, and 1, respectively. Conclusion The resistance rate of INH and SM is relatively high in the Kashgar area. Detection of mutations in RopB, katG, InhA, RpsL, rrs, gyrA, and embB by DNA sequencing can predict drug resistance of M. tuberculosis strains with high sensitivity and specificity, and can be used for diagnosis.

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Distribution of Common Pathogens and Bacterial Resistance in A Tertiary Hospital in China

Tobacco Regulatory Science ◽

10.18001/trs.7.5.98 ◽

2021 ◽

Vol 7 (5) ◽

pp. 1736-1745

Author(s):

Jing Ping ◽

Naiwei Li ◽

Le Huang ◽

Zhaohua Zhou ◽

Xihong Zhang ◽

...

Keyword(s):

Bacterial Resistance ◽

Tertiary Hospital ◽

Drug Susceptibility ◽

Resistance Rate ◽

Coagulase Negative Staphylococcus ◽

Detection Rates ◽

E Coli ◽

Carbapenem Resistant ◽

Resistant Strains ◽

Resistance Rates

We aimed to explore the distribution of common pathogens and bacterial resistance in our hospital from 2017 to 2020, and to standardize clinical medication guidance. The pathogens isolated from the submitted specimens were identified, and drug susceptibility results were interpreted according to the Clinical and Laboratory Standards Institute guidelines (2017-2020). A total of 43,588 specimens were collected from patients treatedfrom 2017 to 2020, and 6,285 strains of pathogens were isolated. The most common pathogens were Escherichia coli, Haemophilus influenzae and Klebsiella pneumoniae.Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 32.85%, and methicillin-resistant coagulase-negative Staphylococcus (MRCNS) accounted for 78.79%. The resistance rates of MRSA and MRCNS to ciprofloxacin, levofloxacin, erythromycin, clindamycin and trimethoprim-sulfamethoxazole were significantly higher than those of methicillin-sensitive S. aureus and methicillin-sensitive coagulase-negative Staphylococcus. The resistance rate of Streptococcus pneumoniae to erythromycin, tetracycline and clindamycin was higher than 80%. The detection rates of E. coli and K. pneumoniae producing ESBL strains were 62.2% and 25.6%, respectively. Totally, 769 carbapenem-resistant strains were detected, of which carbapenem-resistant Acinetobacter baumannii (CRAB) accounted for 66.6%, followed by carbapenem-resistant K. pneumoniae (CRKP) and carbapenem-resistant Pseudomonas aeruginosa (CRPA). A total of 202 CRE strains were detected, which were mainly isolated from respiratory tract and urine specimens. CRAB, CRKP and CRPA had higher resistance rates to antibacterial drugs. Gram-negative bacilli are the most common pathogens from 2017 to 2020. Considering that pathogens have high drug resistance, it is recommended to strengthen clinical management and rational application of antibiotics, thus reducing the risk of nosocomial infections.

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The Increasing Prevalence of Clindamycin Resistance inStaphylococcus aureusIsolates in Children with Head and Neck Abscesses

Canadian Journal of Infectious Diseases and Medical Microbiology ◽

10.1155/2011/261519 ◽

2011 ◽

Vol 22 (2) ◽

pp. 49-51 ◽

Cited By ~ 5

Author(s):

Ashlin J. Alexander ◽

Susan E. Richardson ◽

Alok Sharma ◽

Paolo Campisi

Keyword(s):

Staphylococcus Aureus ◽

Head And Neck ◽

Methicillin Resistance ◽

Neck Region ◽

Empirical Therapy ◽

Resistance Rate ◽

Head And Neck Region ◽

Resistance Patterns ◽

The Mean ◽

Resistance Rates

OBJECTIVE: To retrospectively review trends in clindamycin resistance amongStaphylococcus aureushead and neck abscesses between January 2000 and June 2008.METHODS: Between January 2000 and June 2008, inpatient and out-patientS aureusisolates were reviewed for antibiotic susceptibility. In particular, cultures from 153 abscesses in the head and neck region were assessed for clindamycin and methicillin resistance patterns.RESULTS: Annual clindamycin resistance rates for allS aureusisolates, and specifically forS aureushead and neck abscesses, revealed concerning levels of clindamycin and methicillin resistance. After 2002, the mean clindamycin resistance rate in head and neck abscesses was approximately 27%. The number of new cases of methicillin-resistantS aureusper year increased from four cases in 2000 to 44 cases in 2007.CONCLUSION: Antibiotic resistance should be considered following failed empirical therapy of head and neck abscesses with clindamycin.

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