Bacteria Isolated from Endotracheal Aspirate Samples and Antibiotic Resistance Rates: 5-year Analysis: 5-year Retrospective Analysis

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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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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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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Primary antibiotic resistance of Helicobacter pylori among a Chinese Tibetan population

Future Microbiology ◽

10.2217/fmb-2020-0206 ◽

2020 ◽

Vol 15 (14) ◽

pp. 1353-1361

Author(s):

Xiaoqiong Tang ◽

Xiaohong Chen ◽

Yalin Shen ◽

Tiankuo Yang ◽

Renwei Hu ◽

...

Keyword(s):

Helicobacter Pylori ◽

Antibiotic Resistance ◽

Primary Resistance ◽

Tibetan Population ◽

Disk Diffusion Assay ◽

Treatment Naïve ◽

Gastric Biopsies ◽

H Pylori ◽

Resistance Rates ◽

Diffusion Assay

Aim: To evaluate the primary antibiotic resistance in Helicobacter pylori strains isolated from a Chinese Tibetan population. Methods & materials: Gastric biopsies from 400 H. pylori treatment-naive Tibetan patients were collected for H. pylori isolation. Susceptibility to amoxicillin (AML)/clarithromycin (CLR)/levofloxacin (LEV)/metronidazole (MTZ)/tetracycline (TET)/rifampicin (RIF)/furazolidone (FZD) was determined by E-test or a disk diffusion assay. Results: Biopsies from 117 patients were H. pylori culture positive (29.3%). The primary resistance rates to MTZ, CLR, LEV, RIF, AML, TET and FZD were 90.6, 44.4, 28.2, 69.2, 7.7, 0.8 and 0.8%, respectively. Interestingly, 42.7% of the strains had simultaneous resistance to CLR and MTZ. Conclusion: Among Tibetan strains, primary resistance rates were high for CLR/MTZ/LEV, whereas primary resistance rates to AML/TET/FZD were low. The high resistance to RIF is a concerning finding.

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2049. Trends in Antibiotic Use and Antibiotic Resistance among Veterans Affairs Community Living Centers from 2011 to 2017

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.1729 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S690-S691

Author(s):

Haley Appaneal ◽

Aisling Caffrey ◽

Stephanie Hughes ◽

Vrishali Lopes ◽

Robin L Jump ◽

...

Keyword(s):

Escherichia Coli ◽

Pseudomonas Aeruginosa ◽

Antibiotic Resistance ◽

Antibiotic Use ◽

Veterans Affairs ◽

Fluoroquinolone Resistance ◽

Antibiotic Overuse ◽

Community Living Centers ◽

Resistance Rates ◽

Klebsiella Spp

Abstract Background Antibiotic resistance is a global public health crisis, with antibiotic overuse contributing to selection pressure, and thus driving antibiotic resistance. Strategies to reduce antibiotic overuse may slow the development of resistance, but large-scale studies assessing trends in antibiotic use and resistance among nursing homes at the national level are limited. We describe trends in antibiotic use and resistance nationally among Veterans Affairs (VA) Community Living Centers (CLCs). Methods We assessed antibiotic use and microbiological cultures among VA CLC residents from 2011 to 2017. Antibiotics were grouped into eight drug classes and annual days of antibiotic therapy per 1,000 bed-days were calculated. Facility-weighted annual antibiotic resistance rates were calculated. Joinpoint Software was used for regression analyses of trends over time and to estimate annual average percent changes (AAPC) with 95% confidence intervals (CI). Results Over 7 years and among 146 CLCs, several significant trends in decreasing antibiotic use and corresponding reductions in resistance were identified. Fluoroquinolone use decreased by 9.9% annually (95% CI −11.6 to −8.2%) and fluoroquinolone resistance decreased by 2.3% per year for Escherichia coli, 5.1% for Klebsiella spp., 1.8% for Proteus mirabilis, 4.9% for Pseudomonas aeruginosa, 12.6% for Enterobacter spp., and 3.2% for Enterococcus spp. Anti-pseudomonal penicillin use decreased by 6.6% annually (95% CI −10.6 to −2.4%) and anti-pseudomonal penicillin resistance rates decreased each year by 7.9% for Escherichia coli, 8.9% for Klebsiella spp., 15.2% for Proteus mirabilis and 4.2% for Pseudomonas aeruginosa. Anti-staphylococcal penicillin use decreased by 5.4% annually (95% CI −10.0 to −0.5%) and resistance in Staphylococcus aureus decreased 1.7% per year. Conclusion Nationally among VA CLCs, we observed significant reductions in the use of several classes of antibiotics with corresponding reductions in antibiotic resistance, including an impressive decline in fluoroquinolone use and corresponding decreases in fluoroquinolone resistance among six organisms. Future research should assess whether reductions in antibiotic use predict later reductions in antibiotic resistance and improvements in resident outcomes. Disclosures All authors: No reported disclosures.

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Comparison of Methicillin-Resistant Staphylococcus aureus Isolates from Cellulitis and from Osteomyelitis in a Taiwan Hospital, 2016–2018

Journal of Clinical Medicine ◽

10.3390/jcm8060816 ◽

2019 ◽

Vol 8 (6) ◽

pp. 816 ◽

Cited By ~ 1

Author(s):

Kuo-Ti Peng ◽

Tsung-Yu Huang ◽

Yao-Chang Chiang ◽

Yu-Yi Hsu ◽

Fang-Yi Chuang ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Methicillin Resistant Staphylococcus Aureus ◽

Joint Infection ◽

Sccmec Type ◽

Multidrug Resistant ◽

Chang Gung Memorial Hospital ◽

Methicillin Resistant ◽

Mrsa Strains ◽

Resistance Rates

Methicillin-resistant Staphylococcus aureus (MRSA) causes superficial infections such as cellulitis or invasive infections such as osteomyelitis; however, differences in MRSA isolates from cellulitis (CL-MRSA) and from osteomyelitis (OM-MRSA) at the same local area remain largely unknown. A total of 221 MRSA isolates including 106 CL-MRSA strains and 115 OM-MRSA strains were collected at Chang-Gung Memorial Hospital in Taiwan between 2016 and 2018, and their genotypic and phenotypic characteristics were compared. We found that OM-MRSA isolates significantly exhibited higher rates of resistance to multiple antibiotics than CL-MRSA isolates. Genotypically, OM-MRSA isolates had higher proportions of the SCCmec type III, the sequence type ST239, and the spa type t037 than CL-MRSA isolates. Besides the multidrug-resistant lineage ST239-t037-SCCmecIII more prevalent in OM-MRSA, higher antibiotic resistance rates were also observed in several other prevalent lineages in OM-MRSA as compared to the same lineages in CL-MRSA. Furthermore, when prosthetic joint infection (PJI) associated and non-PJI-associated MRSA strains in osteomyelitis were compared, no significant differences were observed in antibiotic resistance rates between the two groups, albeit more diverse genotypes were found in non-PJI-associated MRSA. Our findings therefore suggest that deep infections may allow MRSA to evade antibiotic attack and facilitate the convergent evolution and selection of multidrug-resistant lineages.

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