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Journal of Clinical Microbiology May 2023Due to limited therapeutic options, there is a clinical need to assess the activity of the combination of aztreonam (ATM) and ceftazidime-avibactam (CZA) to guide the...
Due to limited therapeutic options, there is a clinical need to assess the activity of the combination of aztreonam (ATM) and ceftazidime-avibactam (CZA) to guide the therapeutic management of multidrug-resistant (MDR) Gram-negative organism infections. We set out to develop a practical MIC-based broth disk elution (BDE) method to determine the activity of the combination ATM-CZA using readily available supplies and compare it to reference broth microdilution (BMD). For the BDE method, a 30-μg ATM disk, a 30/20-μg CZA disk, both disks in combination, and no disks were added to 4 separate 5-mL cation-adjusted Mueller-Hinton broth (CA-MHB) tubes, using various manufacturers. Three testing sites performed both BDE and reference BMD testing of bacterial isolates in parallel from a single 0.5 McFarland standard inoculum and after overnight incubation, assessed them for growth (not susceptible) or no growth (susceptible) at a final concentration of 6/6/4 μg/mL ATM-CZA. During the first phase, the precision and accuracy of the BDE were analyzed by testing 61 isolates at all sites. This testing yielded 98.3% precision between sites, with 98.3% categorical agreement and 1.8% major errors (ME). During the second phase, at each site, we evaluated unique, clinical isolates of metallo-β-lactamase (MBL)-producing ( = 75), carbapenem-resistant Pseudomonas aeruginosa ( = 25), Stenotrophomonas maltophilia ( = 46), and sp. ( = 1). This testing resulted in 97.9% categorical agreement, with 2.4% ME. Different results were observed for different disk and CA-MHB manufacturers, requiring a supplemental ATM-CZA-not-susceptible quality control organism to ensure the accuracy of results. The BDE is a precise and effective methodology for determining susceptibility to the combination ATM-CZA.
Topics: Humans; Aztreonam; Anti-Bacterial Agents; Microbial Sensitivity Tests; Ceftazidime; Drug Combinations; Gram-Negative Bacteria; Pseudomonas aeruginosa; beta-Lactamases
PubMed: 37070979
DOI: 10.1128/jcm.01647-22 -
Food Science & Nutrition Feb 2023The aim of this study was to investigate the sensory indicators, biogenic amine contents, and bacterial community structure and diversity of chilled chicken stored at... (Review)
Review
The aim of this study was to investigate the sensory indicators, biogenic amine contents, and bacterial community structure and diversity of chilled chicken stored at 4°C under aerobic conditions. Bacterial diversity and dominant bacteria were analyzed using high-throughput sequencing technique (HTS). The relationship between biogenic amine contents and microbial community structure was studied. The results showed that contents of putrescine and cadaverine increased significantly with storage time. Proteobacteria was absolutely dominant flora at the phylum level. The predominant spoilage bacteria found in chicken thighs were , , , , and , and the difference with chicken breasts was related to the presence of and absence of . , , and were reported for the first time as an important contributor to the spoilage-related microflora Bacterial diversity and richness indices showed fluctuating and decreasing trend with storage time. The redundancy analysis showed that the relative abundance of , , and was positively related to the contents of putrescine, cadaverine, and tyramine, while and showed positive relationship with putrescine content. Furthermore, positive relationship of and with the contents of cadaverine and tyramine was proposed for the first time. The key findings of this study can provide experimental data for food safety monitoring during refrigerated storage and preservation for poultry meat products.
PubMed: 36789075
DOI: 10.1002/fsn3.3122 -
International Journal of Systematic and... Oct 2023An aerobic, Gram-negative, non-motile, yellow-to-orange pigmented and round bacterium, designated strain SCSIO 72103, was isolated from sediment collected in the Pearl...
An aerobic, Gram-negative, non-motile, yellow-to-orange pigmented and round bacterium, designated strain SCSIO 72103, was isolated from sediment collected in the Pearl River Estuary, Guangdong Province, PR China and subjected to a polyphasic taxonomic study. Growth occurred at 20-37 °C (optimum, 28 °C), pH 6-8 (optimum, pH 7) and with 1-5.5% NaCl (optimum, 1-3 %). Comparative 16S rRNA gene analysis indicated that strain SCSIO 72103 had the highest similarities to SNL9 (94.7 %) and SW105 (94.2 %). Phylogenetic analysis based 16S rRNA gene sequences showed that strain SCSIO 72103 formed a single clade with SW105. Strain SCSIO 72103 contained iso-C as the major fatty acid and the predominant respiratory quinone was menaquinone MK-6. These characteristics are consistent with those of SNL9 and SW105. Phosphatidylethanolamine, most notably, unidentified aminolipid and unidentified aminophospholipid were major polar lipids. Strain SCSIO 72103 had a single circular chromosome of 2.96 Mb with a DNA G+C content of 35.1 mol%. The average nucleotide identity, average amino acid identity (AAI) and digital DNA-DNA hybridization values showed that the pairwise similarities between SCSIO 72103 and the type strains of SNL9 and SW105 were 78.5-80.5 %, 79.0-81.4 % and 22.7-22.8 %, respectively. The AAI values between species in this clade and the type species of and were below the 65 % threshold, indicating that these species belong to a novel genus. On the basis of phylogenetic, physiological and chemotaxonomic characteristics, strain SCSIO 72103 represents a new species of a novel genus, for which the name gen. nov. sp. nov. is proposed. The type strain is SCSIO 72103 (=KCTC 92043=MCCC 1K06659). It is also proposed that nine known species in the genera and are reclassified as species.
Topics: Flavobacterium; Estuaries; Phylogeny; RNA, Ribosomal, 16S; Rivers; Base Composition; Fatty Acids; Sequence Analysis, DNA; DNA, Bacterial; Bacterial Typing Techniques; Bacteria, Aerobic; Amino Acids
PubMed: 37882776
DOI: 10.1099/ijsem.0.006091 -
Current Microbiology May 2023Myroides spp. are rare opportunistic pathogens, but they can be life-threatening because of their multidrug-resistant drug properties and their potential to cause...
Antibacterial and Antibiofilm Activities of Ceragenins Alone and in Combination with Levofloxacin Against Multidrug Resistant Myroides spp. Clinical Isolates from Patients with Urinary Tract Infections.
Myroides spp. are rare opportunistic pathogens, but they can be life-threatening because of their multidrug-resistant drug properties and their potential to cause outbreaks, especially in immunosuppressed patients. In this study, 33 isolates isolated from intensive care patients with urinary tract infections were examined for drug susceptibility. All isolates except three proved to be resistant to the tested conventional antibiotics. The effects of ceragenins, a class of compounds developed to mimic endogenous antimicrobial peptides, were evaluated against these organisms. The MIC values of nine ceragenins were determined, and the most effective ceragenins were CSA-131 and CSA-138. Three isolates that were susceptible to levofloxacin and two isolates resistant to all antibiotics underwent 16 s rDNA analysis, and whereas resistant isolates were identified as M. odoratus, susceptible isolates were identified as M. odoratimimus. CSA-131 and CSA-138 showed rapid antimicrobial effects observed in time-kill analyses. Combinations of ceragenins and levofloxacin caused a significant increase in antimicrobial and antibiofilm activities against M. odoratimimus isolates. In this study, Myroides spp. were found to be multidrug-resistant and have biofilm forming capacity, and ceragenins CSA-131 and CSA-138 were found to be especially effective on both planktonic and biofilm forms of Myroides spp.
Topics: Humans; Levofloxacin; Microbial Sensitivity Tests; Anti-Bacterial Agents; Anti-Infective Agents; Urinary Tract Infections; Flavobacteriaceae; Biofilms
PubMed: 37191731
DOI: 10.1007/s00284-023-03321-0 -
Japanese Journal of Infectious Diseases Nov 2023Myroides species have recently been reported more frequently in outbreaks in clinics and intensive care units (ICUs). In this study, we aimed to investigate the epidemic...
Myroides species have recently been reported more frequently in outbreaks in clinics and intensive care units (ICUs). In this study, we aimed to investigate the epidemic potential, antibiotic resistance profile, and risk factors of M. odoratimimus isolates that are increasingly being isolated from the ICUs of our hospital. Data from patients whose Myroides spp. were isolated from their clinical specimens over a 5-year period (September 2016 to January 2022) were retrospectively analyzed. Bacterial identification was performed using a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The presence of antibiotic resistance genes was analyzed using polymerase chain reaction (PCR). Possible clonal associations between isolates were investigated using enterobacterial repetitive intergenic consensus (ERIC)-PCR. As a result, 66 isolates were identified as M. odoratimimus and one isolate was identified as M. odoratus. The bla resistance gene was detected in all M. odoratimimus isolates, whereas sul2 was detected in ten isolates and tetX was detected in 11 isolates. No other resistance genes, such as bla, were detected. Additionally, two different clonal association patterns were discovered in the 24 selected isolates through the ERIC-PCR method. The increase in the immunosuppressive patient population indicate the possibility of encountering this agent and other opportunistic pathogens more frequently in the future.
Topics: Humans; Persistent Infection; Retrospective Studies; Enterobacteriaceae; Drug Resistance, Multiple, Bacterial; Anti-Bacterial Agents; Disease Outbreaks; Hospitals; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 37394461
DOI: 10.7883/yoken.JJID.2023.005 -
Acta Microbiologica Et Immunologica... Mar 2022Myroides spp. are opportunistic environmental Gram-negative bacteria. These affect mostly immunocompromised hosts and generally lead to soft tissue, and urinary tract...
Myroides spp. are opportunistic environmental Gram-negative bacteria. These affect mostly immunocompromised hosts and generally lead to soft tissue, and urinary tract infections. Bacteremia most commonly develop secondary to soft tissue or catheter related infections and may lead rarely to mortality. Myroides spp. are generally suscetible to fluoroquinolones, piperacillin/tazobactam, trimethoprim/sulfamethoxazole, carbapenems or tetracyclines however, pan-resistant isolates and multiple resistance genes have been reported in clinical isolates of Myroides spp. We report a pan-resistant Myroides odoratimimus bacteremia in a patient with severe COVID-19 ending with fatality and in this context a review of reported Myroides bacteremias are also described. In this study, a 64-year old male patient with history of coronary artery bypass was admitted to ICU with severe COVID-19 pneumonia accompanied by pneumomediastinum and pneumopericardium. Continous renal replacement therapy and extracorporeal membraneous-oxygenation were initiated due to acute renal failure and persistent hypercarbia/hypoxia, respectively. Within four weeks of hospitalization various episodes of bacteremia developed and multiple antibiotics were used. On the 5th week of follow-up, acute phase reactants increased and empirical broad spectrum antibiotics were initiated. Blood culture revealed Gram-negative rods. The patient became hypotensive and despite maximum medical care he was lost due to cardiac arrest. M. odoratimimus was identified by MALDI-TOF and the bacterium was pan-resistant. According to Center for Genomic Epidemiology results the strain was identified as M. odoratimimus PR63039 and the genome analysis revealed antibiotic resistance genes associated with resistance to beta-lactams (bla OXA-347, bla MUS-1, bla EBR-1), tetracyclines (tetX), sulfonamides (sul2), macrolides (ereD), (ermF).
PubMed: 35312630
DOI: 10.1556/030.2022.01702 -
The Journal of Hospital Infection Jul 2023Myroides spp. are Gram-negative bacilli that are commonly found in soil and water, acting as low-level opportunistic pathogens and causing a variety of infections.
BACKGROUND
Myroides spp. are Gram-negative bacilli that are commonly found in soil and water, acting as low-level opportunistic pathogens and causing a variety of infections.
AIM
To assess the risk factors for multi-drug-resistant myroides infections, association with comorbid illnesses, patient care and susceptibility to antibiotics.
METHODS
This retrospective analytical study was conducted in Istanbul Başakşehir Çam and Sakura City Hospital, and included patients with Myroides spp. isolated in their culture samples. Total hospitalization days, first isolation day and 30-day mortality values of the patients were analysed statistically, and P<0.05 was considered to indicate significance.
RESULTS
Myroides spp. were isolated from 437 culture samples from 228 patients. Of these cases, 210 (92.1%) were classified as having asymptomatic bacteriuria, and 18 (7.9%) as having an infection caused by Myroides spp. One hundred and seventy-four (76.3%) patients were followed up in the intensive care unit, and total hospitalization days (median 24.5 days) and first isolation day (median 9.5 days) of infected patients were shorter than those for colonized patients (P=0.023 and 0.030, respectively). No difference was found in 30-day mortality between infected and colonized patients (P=0.312).
CONCLUSIONS
Myroides infections were seen more frequently in patients who were hospitalized for a long time, used broad-spectrum antimicrobials, underwent invasive procedures, and had co-factors such as diabetes and cerebrovascular disease. In addition, the resistance rates of Myroides odoratus were higher than those of Myroides odoratimimus, and the use of quinolones for the treatment of patients with M. odoratimimus infection led to a higher cure rate.
Topics: Humans; Retrospective Studies; Gram-Negative Bacteria; Anti-Bacterial Agents; Bacteria, Aerobic; Risk Factors; Intensive Care Units
PubMed: 37094716
DOI: 10.1016/j.jhin.2023.04.010 -
The Journal of Antimicrobial... Jun 2020To report a novel tigecycline resistance gene, tet(X6), and its variants in four bacterial species isolated from chickens and pigs in China.
OBJECTIVES
To report a novel tigecycline resistance gene, tet(X6), and its variants in four bacterial species isolated from chickens and pigs in China.
METHODS
WGS was conducted to identify the suspected resistance genes in the tigecycline-resistant Myroides phaeus 18QD1AZ29W. Functional cloning, homology modelling and molecular docking were performed to compare the function with other Tet(X) variants. Retrospective screening for tet(X6) was conducted for 80 isolates in our WGS data collection, and all genomic environments of tet(X6)-positive isolates were analysed.
RESULTS
The tigecycline-resistant M. phaeus 18QD1AZ29W isolated from a pig farm in Shandong in 2018 was positive for tet(X2) and a novel tet(X) gene, designated tet(X6). Tet(X6) could increase the MICs of all tested tetracyclines/glycylcyclines for Escherichia coli only 2- to 4-fold, which was possibly due to a lower tetracycline binding capacity of Tet(X6) compared with that of other Tet(X) variants. Retrospective screening showed that seven other isolates (7/80, 8.8%), comprising four Proteus spp. and three Acinetobacter spp. from chickens and pigs in Shandong and Guangdong, were positive for three different variants of tet(X6). The analysis of the genomic environment revealed that two tet(X6)-positive isolates from M. phaeus and Proteus cibarius, respectively, contained ISCR2, which may play a role in tet(X6) transmission.
CONCLUSIONS
This study identified a novel type of tigecycline resistance gene, tet(X6), in Myroides, Acinetobacter and Proteus from chickens and swine. Tet(X6) conferred lower tetracycline/glycylcycline MICs than other Tet(X) variants, and ISCR2 may play a role in the transmission of tet(X6).
Topics: Acinetobacter; Animals; Anti-Bacterial Agents; Chickens; China; Flavobacteriaceae; Microbial Sensitivity Tests; Molecular Docking Simulation; Proteus; Retrospective Studies; Swine; Tetracycline Resistance; Tigecycline
PubMed: 32068864
DOI: 10.1093/jac/dkaa037 -
IDCases 2021Formerly classified under the genus species are common gram-negative, environmental bacterium ubiquitous in soil and water. While infrequent, infections of human hosts...
Formerly classified under the genus species are common gram-negative, environmental bacterium ubiquitous in soil and water. While infrequent, infections of human hosts can result in devastating consequences due the bacteria's intrinsic multidrug resistance, particularly in those who are immunocompromised. The pathogenicity and mechanisms for resistance remain poorly understood at this time. The case presented in this report details bacteremia secondary to a soft tissue infection of the lower extremities and adds to the 60 documented infections to date, of which 15 were also characterized by a similar infection.
PubMed: 33850715
DOI: 10.1016/j.idcr.2021.e01061 -
Indian Journal of Critical Care... Apr 2024species are ubiquitous in the environment and cause a variety of infections like urinary tract infections (UTI), sepsis, meningitis, cholecystitis, pneumonia, and soft...
AIM AND BACKGROUND
species are ubiquitous in the environment and cause a variety of infections like urinary tract infections (UTI), sepsis, meningitis, cholecystitis, pneumonia, and soft tissue infections, especially among immunocompromised populations. These are usually resistant to multiple antibiotics. This study aimed to demonstrate the clinical profile, underlying comorbidities, and antimicrobial susceptibility of isolates obtained from nosocomial UTI cases.
MATERIALS AND METHODS
A sudden rise in the isolation of spp. from the repeated urine samples of admitted patients alerted us to conduct this retrospective observational study. Urine cultures that grew species were included in this study. Antibiotic susceptibility was performed and the patient's clinical data was analyzed.
RESULTS
A total of 14 spp. isolates were obtained from urine culture. The maximum number of cases (71.4%) were from the Nephrology ward and ICUs. The average (mean) age of patients was 46 years (range 2-80 years). All patients were catheterized. All isolates were multidrug resistant. Minocycline and doxycycline were the only drugs found effective in this study.
CONCLUSIONS
species are emerging rare pathogens that can cause UTI in immunocompromised and catheterized patients. Minocycline may be used for treating such infections.
HOW TO CITE THIS ARTICLE
Sahu C, Chaudhary R, Bhartiya C, Patel SS, Bhatnagar N. A Retrospective Study on UTI by Species: An Emerging Drug Resistant Nosocomial Pathogen. Indian J Crit Care Med 2024;28(4):399-403.
PubMed: 38585315
DOI: 10.5005/jp-journals-10071-24683