Antibiotic Resistance Rates by Geographic Region Among Ocular Pathogens Collected During the ARMOR Surveillance Study

A surveillance study on antibiotic resistance of enterococcal isolates (n = 730) was carried out in North Rhine-Westphalia, Germany, in 1997. Resistance rates to ampicillin (7.4%), high-level gentamicin (15.0%), high-level streptomycin (27.9%), ciprofloxacin (37.9%), vancomycin (1.5%), and teicoplanin (1.5%) were determined. All vancomycin-resistant enterococci (VRE) carried the vanA gene. SmaI andApaI macrorestriction patterns indicated an intra- and interhospital spread of VRE.

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The Role of Aquatic Ecosystems (River Tua, Portugal) as Reservoirs of Multidrug-Resistant Aeromonas spp.

Water ◽

10.3390/w13050698 ◽

2021 ◽

Vol 13 (5) ◽

pp. 698

Author(s):

Sónia Gomes ◽

Conceição Fernandes ◽

Sandra Monteiro ◽

Edna Cabecinha ◽

Amílcar Teixeira ◽

...

Keyword(s):

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Nalidixic Acid ◽

Water Samples ◽

Aquatic Ecosystems ◽

Anthropogenic Activities ◽

Aquatic Organisms ◽

Resistant Bacteria ◽

Anthropogenic Pressures ◽

Resistance Rates

The inappropriate use of antibiotics, one of the causes of the high incidence of antimicrobial-resistant bacteria isolated from aquatic ecosystems, represents a risk for aquatic organisms and the welfare of humans. This study aimed to determine the antimicrobial resistance rates among riverine Aeromonas spp., taken as representative of the autochthonous microbiota, to evaluate the level of antibacterial resistance in the Tua River (Douro basin). The prevalence and degree of antibiotic resistance was examined using motile aeromonads as a potential indicator of antimicrobial susceptibility for the aquatic environment. Water samples were collected from the middle sector of the river, which is most impacted area by several anthropogenic pressures. Water samples were plated on an Aeromonas-selective agar, with and without antibiotics. The activity of 19 antibiotics was studied against 30 isolates of Aeromonas spp. using the standard agar dilution susceptibility test. Antibiotic resistance rates were fosfomycin (FOS) 83.33%, nalidixic acid (NA) 60%, cefotaxime (CTX) 40%, gentamicin (CN) 26.67%, tobramycin (TOB) 26.67%, cotrimoxazole (SXT) 26.67%, chloramphenicol (C) 16.67%, and tetracycline (TE) 13.33%. Some of the nalidixic acid-resistant strains were susceptible to fluoroquinolones. Multiple resistance was also observed (83.33%). The environmental ubiquity, the natural susceptibility to antimicrobials and the zoonotic potential of Aeromonas spp. make them optimal candidates for studying antimicrobial resistance (AMR) in aquatic ecosystems. Aquatic environments may provide an ideal setting for the acquisition and dissemination of antibiotic resistance because anthropogenic activities frequently impact them. The potential risk of multi- and pan-resistant bacteria transmission between animals and humans should be considered in a “One Health—One World” concept.

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Animal and Human Multidrug-Resistant, Cephalosporin-ResistantSalmonella Isolates Expressing a Plasmid-Mediated CMY-2 AmpC β-Lactamase

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.10.2777-2783.2000 ◽

2000 ◽

Vol 44 (10) ◽

pp. 2777-2783 ◽

Cited By ~ 174

Author(s):

P. L. Winokur ◽

A. Brueggemann ◽

D. L. DeSalvo ◽

L. Hoffmann ◽

M. D. Apley ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Plasmid Dna ◽

Antibiotic Use ◽

Multidrug Resistant ◽

Geographic Region ◽

Chromosomal Dna ◽

Important Food ◽

Food Borne ◽

Clonal Spread ◽

Resistance Rates

ABSTRACT Salmonella spp. are important food-borne pathogens that are demonstrating increasing antimicrobial resistance rates in isolates obtained from food animals and humans. In this study, 10 multidrug-resistant, cephalosporin-resistant Salmonellaisolates from bovine, porcine, and human sources from a single geographic region were identified. All isolates demonstrated resistance to cephamycins and extended-spectrum cephalosporins as well as tetracycline, chloramphenicol, streptomycin, and sulfisoxazole. Molecular epidemiological analyses revealed eight distinct chromosomal DNA patterns, suggesting that clonal spread could not entirely explain the distribution of this antimicrobial resistance phenotype. However, all isolates encoded an AmpC-like β-lactamase, CMY-2. Eight isolates contained a large nonconjugative plasmid that could transformEscherichia coli. Transformants coexpressed cephalosporin, tetracycline, chloramphenicol, streptomycin, and sulfisoxazole resistances. Plasmid DNA revealed highly related restriction fragments though plasmids appeared to have undergone some evolution over time. Multidrug-resistant, cephalosporin-resistant Salmonellaspp. present significant therapeutic problems in animal and human health care and raise further questions about the association between antimicrobial resistance, antibiotic use in animals, and transfer of multidrug-resistant Salmonella spp. between animals and man.

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Methicillin-resistant Staphylococcus aureus of the clonal lineage ST5-SCCmecII-t2460 was associated with high mortality in a Wuhan hospital

Brazilian Journal of Microbiology ◽

10.1007/s42770-021-00557-5 ◽

2021 ◽

Author(s):

Xuehan Li ◽

Jing Zhang ◽

Yifan Zhang ◽

Junying Zhou ◽

Xinwei Li ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

White Blood Cells ◽

Resistance Rate ◽

Molecular Characteristics ◽

Invasive Procedures ◽

Methicillin Resistant ◽

Small Colony Variant ◽

Recent Emergence ◽

Resistance Rates

AbstractMethicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen that can cause serious infectious diseases. An emerging MRSA strain, ST5-SCCmecII spa-type-t2460 (SMRSA), has spread rapidly since its recent emergence in China, but little information is available about this lineage. In this study, 91 MRSA isolates were collected from patients treated in the Zhongnan Hospital, Wuhan University, from 2018 to 2019, and investigated for their molecular characteristics, antibiotic resistance profiles, and clinical characteristics. The predominant lineage, SMRSA, accounted for 37.4% (34/91) of the isolates, followed by ST239-SCCmecIII-t030 (19.8%, 18/91) and ST59-SCCmecIV-t437 (8.8%, 8/91). In contrast to the latter two non-SMRSA (nSMRSA) lineages, which are among the main MRSA found in Chinese settings, SMRSA exhibited small colony variant (SCV) phenotype and had extremely high resistance rates to erythromycin (100.0%), clindamycin (100.0%), levofloxacin (100.0%), tetracycline (97.1%), moxifloxacin (97.1%), and ciprofloxacin (100%), but was more susceptible to rifampicin (resistance rate 3%). The levels of white blood cells (WBC) and procalcitonin (PCT) and the 30-day mortality in patients infected with SMRSA were (12.54 ± 6.61) × 109/L, 0.66 ng/mL, and 52.9%, respectively, which were much higher than those in patients infected with nSMRSA. In addition, patients infected with SMRSA were more frequently admitted to the intensive care unit (ICU) and submitted to invasive procedures than those infected with nSMRSA. In conclusion, SMRSA showed SCV phenotype and exhibited multiple antibiotic-resistance profiles. In this study, SMRSA was associated with serious infections and poor prognosis. Compared with ST239, ST59, or other nSMRSA strains, patients infected with SMRSA strains have higher 30-day mortality, increased levels of inflammatory biomarkers, and more frequent ICU hospitalization and invasive procedures.

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Prevalence of Antimicrobial-Resistant Pathogens in Canadian Hospitals: Results of the Canadian Ward Surveillance Study (CANWARD 2008)

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00469-10 ◽

2010 ◽

Vol 54 (11) ◽

pp. 4684-4693 ◽

Cited By ~ 92

Author(s):

George G. Zhanel ◽

Melanie DeCorby ◽

Heather Adam ◽

Michael R. Mulvey ◽

Melissa McCracken ◽

...

Keyword(s):

Staphylococcus Epidermidis ◽

Susceptibility Testing ◽

Multidrug Resistant ◽

Surveillance Study ◽

Bacterial Isolates ◽

Coagulase Negative Staphylococci ◽

Clinical Specimens ◽

E Coli ◽

Polymyxin E ◽

Resistance Rates

ABSTRACT A total of 5,282 bacterial isolates obtained between 1 January and 31 December 31 2008, inclusive, from patients in 10 hospitals across Canada as part of the Canadian Ward Surveillance Study (CANWARD 2008) underwent susceptibility testing. The 10 most common organisms, representing 78.8% of all clinical specimens, were as follows: Escherichia coli (21.4%), methicillin-susceptible Staphylococcus aureus (MSSA; 13.9%), Streptococcus pneumoniae (10.3%), Pseudomonas aeruginosa (7.1%), Klebsiella pneumoniae (6.0%), coagulase-negative staphylococci/Staphylococcus epidermidis (5.4%), methicillin-resistant S. aureus (MRSA; 5.1%), Haemophilus influenzae (4.1%), Enterococcus spp. (3.3%), Enterobacter cloacae (2.2%). MRSA comprised 27.0% (272/1,007) of all S. aureus isolates (genotypically, 68.8% of MRSA were health care associated [HA-MRSA] and 27.6% were community associated [CA-MRSA]). Extended-spectrum β-lactamase (ESBL)-producing E. coli occurred in 4.9% of E. coli isolates. The CTX-M type was the predominant ESBL, with CTX-M-15 the most prevalent genotype. MRSA demonstrated no resistance to ceftobiprole, daptomycin, linezolid, telavancin, tigecycline, or vancomycin (0.4% intermediate intermediate resistance). E. coli demonstrated no resistance to ertapenem, meropenem, or tigecycline. Resistance rates with P. aeruginosa were as follows: colistin (polymyxin E), 0.8%; amikacin, 3.5%; cefepime, 7.2%; gentamicin, 12.3%; fluoroquinolones, 19.0 to 24.1%; meropenem, 5.6%; piperacillin-tazobactam, 8.0%. A multidrug-resistant (MDR) phenotype occurred frequently in P. aeruginosa (5.9%) but uncommonly in E. coli (1.2%) and K. pneumoniae (0.9%). In conclusion, E. coli, S. aureus (MSSA and MRSA), P. aeruginosa, S. pneumoniae, K. pneumoniae, H. influenzae, and Enterococcus spp. are the most common isolates recovered from clinical specimens in Canadian hospitals. The prevalence of MRSA was 27.0% (of which genotypically 27.6% were CA-MRSA), while ESBL-producing E. coli occurred in 4.9% of isolates. An MDR phenotype was common in P. aeruginosa.

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In Vitro Activity of Cefepime against Multidrug-Resistant Gram-Negative Bacilli, Viridans Group Streptococci andStreptococcus pneumoniaefrom a Cross-Canada Surveillance Study

Canadian Journal of Infectious Diseases ◽

10.1155/1999/172031 ◽

1999 ◽

Vol 10 (2) ◽

pp. 122-127 ◽

Cited By ~ 2

Author(s):

Donald E Low ◽

Joyce de Azavedo ◽

Canadian Bacterial Surveillance Network ◽

Ross Davidson

Keyword(s):

Susceptibility Testing ◽

Multidrug Resistant ◽

Vitro Activity ◽

Surveillance Study ◽

National Committee ◽

In Vitro Activity ◽

Gram Negative ◽

Resistance Rates ◽

Viridans Group Streptococci

OBJECTIVE: To determine the in vitro activity of cefepime against multidrug-resistant Gram-negative bacilli and Gram-positive cocci obtained from an ongoing cross-Canada surveillance study.DESIGN: Clinical isolates of aerobic Gram-negative bacilli with inducible and constitutive chromosomally mediated cephalosporinases, viridans group streptococci andStreptococcus pneumoniaewere collected from laboratories serving hospitals, nursing homes and physician offices in the community from across Canada during 1996 and 1997. Laboratories were asked to submit only clinically relevant nonduplicate isolates for susceptibility testing. In vitro antimicrobial susceptibility testing was carried out on all isolates of Gram-negative and viridans group streptococci.S pneumoniaewere characterized as penicillin susceptible, intermediately resistant or highly resistant. Nonsusceptible isolates were defined as being intermediately or highly resistant (minimal inhibitory concentrations [MIC] greater than 0.06 mg/L). Only isolates ofS pneumoniaethat were nonsusceptible to penicillin were selected for further study. MICs were determined using a microbroth dilution technique according to the National Committee of Clinical Laboratory Standards.RESULTS: A total of 727 Gram-negative bacilli samples were collected. No resistance to cefepime was detected withCitrobacter freundii,Serratia marcescens,Morganella morganiiandEnterobacterspecies. Of these strains,Enterobacterspecies andC freundiiwere the most resistant to ceftazidime, cefotaxime and ceftriaxone with MIC90Sof 32 mg/L or greater and resistance rates of 6% or greater. Resistance rates ofPseudomonas aeruginosaandAcinetobacterspecies to cefepime were 4.8% and 3%, respectively. The two organisms had similar rates of resistance to ceftazidime. Less than 3% of the Gram-negative bacilli were resistant to imipenem and meropenem. There were 153 viridans group streptococci, of which 22 (14.4%) were resistant to penicillin. Of 1287S pneumoniaesamples, 193 (15%) were nonsusceptible to penicillin. Cefepime, ceftriaxone and cefotaxime had comparable activity against all isolates of viridans group streptococci andS pneumoniae.CONCLUSIONS: Cefepime demonstrated excellent in vitro activity against Gram-negative bacilli with inducible and constitutive chromosomally mediated cephalosporinases, and had equal or superior activity versus comparator beta-lactams against all isolates of viridans group streptococci andS pneumoniae.

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Antibiotic Resistance of Helicobacter pylori Strains Isolated From Pediatric Patients in Southwest China

Frontiers in Microbiology ◽

10.3389/fmicb.2020.621791 ◽

2021 ◽

Vol 11 ◽

Author(s):

Juan Li ◽

Jianjun Deng ◽

Zhiling Wang ◽

Hong Li ◽

Chaomin Wan

Keyword(s):

Helicobacter Pylori ◽

Antibiotic Resistance ◽

Pediatric Patients ◽

Southwest China ◽

Pediatric Population ◽

Primary Resistance ◽

Secondary Resistance ◽

Treatment Naïve ◽

H Pylori ◽

Resistance Rates

The number of antibiotics that are appropriate for Helicobacter pylori eradication in children is limited. Profiling regional or population-specific antibiotic resistance is essential in guiding the H. pylori eradication treatment in children. The aim of this study was to evaluate the antibiotic resistance in H. pylori strains isolated from children and adolescents in Southwest China. Gastric biopsies from 157 pediatric patients with or without previous H. pylori eradication treatment were collected for H. pylori culture. Susceptibility to amoxicillin (AML), clarithromycin (CLR), metronidazole (MTZ), levofloxacin (LEV), tetracycline (TET), furazolidone (FZD), and rifampicin (RIF) was determined by E-test or a disk diffusion assay. A total of 87 patients from three ethnic groups (Han/Tibetan/Yi) were H. pylori culture positive (55.4%). The overall resistance rates were 55.2% for CLR, 71.3% for MTZ, 60.9% for RIF, and 18.4% for LEV. No isolate was found to be resistant to AML, TET, and FZD. Among the 53 treatment-naïve pediatric patients, primary resistance rates to clarithromycin, metronidazole, levofloxacin, and rifampicin were 45.3, 73.6, 15.1, and 60.4%, respectively. Among the 34 treatment-experienced patients, secondary resistance rates to clarithromycin, metronidazole, levofloxacin, and rifampicin were 70.6, 67.6, 23.5, and 61.8%, respectively. Isolates exhibiting simultaneous resistance to clarithromycin and metronidazole were 28.3 and 52.9% among the treatment-naïve and treatment-experienced patients, respectively. In conclusion, among pediatric patients in Southwest China, resistance rates were high for clarithromycin, metronidazole, levofloxacin, and rifampicin, whereas nil resistance was found to amoxicillin, tetracycline, and furazolidone. Our data suggest that the standard clarithromycin-based triple therapy should be abandoned as empiric therapy, whereas the bismuth quadruple therapy (bismuth/PPI/amoxicillin/tetracycline) would be suitable as first-line empiric treatment regimen for this pediatric population. Tetracycline and furazolidone may be considered for treating refractory H. pylori infections in adolescent patients.

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Prevalence of Virulence Genes and Drug Resistance Profiles of Pseudomonas aeruginosa Isolated From Clinical Specimens

Jundishapur Journal of Microbiology ◽

10.5812/jjm.118452 ◽

2021 ◽

Vol 14 (8) ◽

Author(s):

Seyed Ali Bazghandi ◽

Mohsen Arzanlou ◽

Hadi Peeridogaheh ◽

Hamid Vaez ◽

Amirhossein Sahebkar ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Resistance ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Virulence Gene ◽

Clinical Isolates ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Clinical Specimens ◽

Resistance Rates

Background: Drug resistance and virulence genes are two key factors for the colonization of Pseudomonas aeruginosa in settings with high antibiotic pressure, such as hospitals, and the development of hospital-acquired infections. Objectives: The objective of this study was to investigate the prevalence of drug resistance and virulence gene profiles in clinical isolates of P. aeruginosa in Ardabil, Iran. Methods: A total of 84 P. aeruginosa isolates were collected from clinical specimens of Ardabil hospitals and confirmed using laboratory standard tests. The disk diffusion method was used for antibiotic susceptibility testing and polymerase chain reaction (PCR) for the identification of P. aeruginosa virulence genes. Results: The highest and the lowest antibiotic resistance rates of P. aeruginosa strains were against ticarcillin-clavulanate (94%) and doripenem (33.3%), respectively. In addition, the frequency of multidrug-resistant (MDR) P. aeruginosa was 55.9%. The prevalence of virulence factor genes was as follows: algD 84.5%, lasB 86.9%, plcH 86.9%, plcN 86.9%, exoU 56%, exoS 51.2%, toxA 81%, nan1 13.1%, and pilB 33.3%. A significant association was observed between resistance to some antibiotics and the prevalence of virulence genes in P. aeruginosa. Conclusions: Our results revealed a high prevalence of antibiotic resistance, especially MDR, and virulence-associated genes in clinical isolates of P. aeruginosa in Ardabil hospitals. Owing to the low resistance rates against doripenem, gentamicin, and tobramycin, these antibiotics are recommended for the treatment of infections caused by highly resistant and virulent P. aeruginosa strains.

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Antibiotic Resistance Profile and Chemical Quality Assessment of Groundwater Sources from Periurban Area of Bucharest, Romania

Revista de Chimie ◽

10.37358/rc.19.10.7594 ◽

2019 ◽

Vol 70 (10) ◽

pp. 3549-3554

Author(s):

Florica Marinescu ◽

Mihaela Ilie ◽

Gina Ghita ◽

Ioana Savin ◽

Carmen Tociu ◽

...

Keyword(s):

Antibiotic Resistance ◽

Multiple Drug Resistance ◽

Microbiological Quality ◽

Shallow Groundwater ◽

Total Coliform ◽

Multiple Drug ◽

Maximum Admissible Concentration ◽

Antibiotic Resistance Profile ◽

Physico Chemical ◽

Resistance Rates

Twenty-two groundwater sources mainly used for drinking purpose in Bucharest peri-urban area were investigated for assessment of physico-chemical and microbiological quality with a view to determining its potential risk to public health. Results of chemical analysis revealed that nitrites, sulphates and chlorides were below the permissible levels, while 63.64% of the analysed groundwater sources exceeded the maximum admissible concentration for nitrates, with concentration variations ranging from 67.27 to 523.19 mg/L. The bacteriological analysis showed that in about 63% of groundwater sources total coliform, faecal coliform and enterococci have exceeded the threshold limits recommended by the Drinking Water Directive 98/83/EC and the Romanian Law. Another aim of the study was to investigate the prevalence of antibiotic resistance among Gram-negative strains isolated from groundwater sources. There observed the resistance to many antibiotics, particularly: ticarcillin (80%), aztreonam (29%), gentamicin (11%), imipenem (9%), ceftriaxone (9%), ceftazidime (3%) and ciprofloxacin (3%). Significant higher resistance rates were observed in strains isolated from shallow groundwater sources as compared with strains isolated from deep groundwater sources. Pseudomonas sp. (26%) isolates with multiple-drug resistance (MDR) were encountered. The results of the study revealed a bacteriological contamination and high levels of nitrate concentrations in most of the groundwater samples, which could pose an important risk to human health.

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An outbreak of methicillin resistant Staphylococcus epidermidis among neonates in a hospital in Saudi Arabia

The Journal of Infection in Developing Countries ◽

10.3855/jidc.1293 ◽

2011 ◽

Vol 5 (10) ◽

pp. 692-699 ◽

Cited By ~ 4

Author(s):

Maha Abd El Hafez ◽

Noha G. Khalaf ◽

Mohamed El Ahmady ◽

Ahmed Abd El Aziz ◽

Abd El Gawad Hashim

Keyword(s):

Saudi Arabia ◽

Antibiotic Resistance ◽

Staphylococcus Epidermidis ◽

Neonatal Intensive Care ◽

Meca Gene ◽

Neonatal Intensive Care Units ◽

Methicillin Resistant ◽

Resistance Patterns ◽

Clonal Origin ◽

Resistance Rates

Introduction: Staphylococcus epidermidis is a pathogen associated with nosocomial infection in neonatal intensive care units (NICU). This study investigates an outbreak of methicillin resistant S. epidermidis in an NICU in a hospital in Saudi Arabia. Methodology: A total of 41 isolates identified as Gram-positive cocci were obtained from blood culture, umbilical wound swabs and endotracheal aspirate specimens of neonates, of which 29 were identified as S. epidermidis. Bacterial identification at the species level and determination of antibiotic resistance were performed by MicroScan (Dade Behring, USA). Genotyping was completed using randomly amplified polymorphic DNA (RAPD) and the mecA gene was detected by PCR. Results: All 29 S. epidermidis isolates were found to be resistant to oxacillin and were positive for the mecA gene. The isolates showed several multidrug-resistance patterns; the resistance rates to gentamicin, erythromycin, clindamycin, and trimethoprim/sulfamethoxazole were 89.7%, 86.2%, 75.9% and 72.4%, respectively. All isolates were susceptible to vancomycin, teicoplanin, rifampin, synercid, and ciprofloxacin. Several genotypic and phenotypic patterns were detected among the S. epidermidis isolates: antibiogram typing showed seven different patterns, one of which was shared by 65% of the isolates, whereas the most prevalent RAPD genotype was shared by only five S. epidermidis isolates, and did not correlate with antibiotic resistance phenotype. Conclusion: The diverse clonal origin of tested isolates indicates the presence of multiple S. epidermidis strains among neonates in the NICU setting

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