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Microbiology Spectrum Dec 2023This study first reported the effector kinetics of the new non-fluorinated quinolone, nemonoxacin, against macrolide-resistant (MRMP) and macrolide susceptible (MSMP)...
This study first reported the effector kinetics of the new non-fluorinated quinolone, nemonoxacin, against macrolide-resistant (MRMP) and macrolide susceptible (MSMP) strains along with other antimicrobial agents. The time-kill assays and pharmacodynamic analysis showed that nemonoxacin has significant mycoplasmacidal activity against MRMP and MSMP. This study paves the road to establish appropriate dosing protocols of a new antimicrobial drug for children infected with .
Topics: Child; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Anti-Bacterial Agents; Quinolones; Macrolides; Drug Resistance, Bacterial; Microbial Sensitivity Tests
PubMed: 37975686
DOI: 10.1128/spectrum.02431-23 -
Advances in Experimental Medicine and... 2024Clostridioides difficile infection (CDI) remains a significant cause of morbidity and mortality worldwide. Historically, two antibiotics (metronidazole and vancomycin)...
Clostridioides difficile infection (CDI) remains a significant cause of morbidity and mortality worldwide. Historically, two antibiotics (metronidazole and vancomycin) and a recent third (fidaxomicin) have been used for CDI treatment; convincing data are now available showing that metronidazole is the least efficacious agent. The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) management guidance for CDI were updated in 2021. This guidance document outlines the treatment options for a variety of CDI clinical scenarios and for non-antimicrobial management (e.g., faecal microbiota transplantation, FMT). One of the main changes is that metronidazole is no longer recommended as first-line CDI treatment. Rather, fidaxomicin is preferred on the basis of reduced recurrence rates with vancomycin as an acceptable alternative. Recommended options for recurrent CDI now include bezlotoxumab as well as FMT.A 2017 survey of 20 European countries highlighted variation internationally in CDI management strategies. A variety of restrictions were in place in 65% countries prior to use of new anti-CDI treatments, including committee/infection specialist approval or economic review/restrictions. This survey was repeated in November 2022 to assess the current landscape of CDI management practices in Europe. Of 64 respondents from 17 countries, national CDI guidelines existed in 14 countries, and 11 have already/plan to incorporate the ESCMID 2021 CDI guidance, though implementation has not been surveyed in 6. Vancomycin is the most commonly used first-line agent for the treatment of CDI (n = 42, 66%), followed by fidaxomicin (n = 30, 47%). Six (9%) respondents use metronidazole as first-line agent for CDI treatment, whereas 22 (34%) only in selected low-risk patient groups. Fidaxomicin is more likely to be used in high-risk patient groups. Availability of anti-CDI therapy influenced prescribing in six respondents (9%). Approval pre-prescription was required before vancomycin (n = 3, 5%), fidaxomicin (n = 10, 6%), bezlotoxumab (n = 11, 17%) and FMT (n = 10, 6%). Implementation of CDI guidelines is rarely audited.Novel anti-CDI agents are being evaluated; it is not yet clear what will be the roles of these agents. The treatment of recurrent CDI is particularly troublesome, and several different live biotherapeutics are being developed, in addition to FMT.
Topics: Humans; Fidaxomicin; Metronidazole; Vancomycin; Anti-Bacterial Agents; Clostridium Infections
PubMed: 38175471
DOI: 10.1007/978-3-031-42108-2_4 -
Helicobacter Oct 2023Antibiotic resistance is a well-known factor of Helicobacter pylori eradication failure. Heteroresistance indicates the coexistence of resistant and susceptible strains...
BACKGROUND
Antibiotic resistance is a well-known factor of Helicobacter pylori eradication failure. Heteroresistance indicates the coexistence of resistant and susceptible strains and might lead to underestimating antimicrobial resistance. This study aims to evaluate the susceptibility profile, the frequency of heteroresistance of H. pylori strains, and their effect on eradication success in a pediatric population.
MATERIALS AND METHODS
Children aged 2-17 years who underwent an upper gastrointestinal endoscopy from 2011 to 2019 with positive H. pylori status were included. Susceptibility was measured by disk diffusion and E-test. The difference in susceptibility profiles between isolates from the antrum and the corpus was used to detect heteroresistance. For those who received eradication treatment, we evaluated eradication rate and factors affecting treatment success.
RESULTS
Inclusion criteria were met by 565 children. Strains susceptible to all antibiotics were detected in 64.2%. Primary resistance rates for clarithromycin (CLA), metronidazole (MET), levofloxacin (LEV), tetracyclin (TET), and amoxicillin (AMO) were 11%, 22.9%, 6.9%, 0.4%, and 0% and secondary resistance rates were 20.4%, 29.4%, 9.3%, 0%, and 0%. Heteroresistance was present in untreated children in 2%, 7.1%, 0.7%, 0.7%, and 0% for CLA, MET, LEV, TET, and AMO. First-line eradication rates were 78.5% in intention-to-treat (ITT), 88.3% in full-analysis-set (FAS), and 94.1% in per-protocol (PP). Factors affecting eradication success were the duration of treatment when the triple-tailored treatment was used, the number of daily doses of amoxicillin administered, and the patient's adherence to treatment.
CONCLUSIONS
This study shows the presence of relatively low primary resistance rates for H. pylori isolates but demonstrates the presence of heteroresistance in our population. Routine biopsies from the antrum and corpus must be considered for susceptibility testing to allow tailored treatments and increase eradication rates. Treatment success is affected by treatment choice, correct dosing of medications, and adherence. All these factors should be considered when evaluating the efficacy of an eradication regimen.
Topics: Child; Humans; Helicobacter Infections; Helicobacter pylori; Anti-Bacterial Agents; Clarithromycin; Amoxicillin; Metronidazole; Levofloxacin; Drug Resistance, Bacterial; Tetracycline; Drug Therapy, Combination
PubMed: 37402147
DOI: 10.1111/hel.13006 -
BMC Microbiology Aug 2023The microbiome of the human gut serves a role in a number of physiological processes, but can be altered through effects of age, diet, and disturbances such as...
BACKGROUND
The microbiome of the human gut serves a role in a number of physiological processes, but can be altered through effects of age, diet, and disturbances such as antibiotics. Several studies have demonstrated that commonly used antibiotics can have sustained impacts on the diversity and the composition of the gut microbiome. The impact of the two most overused antibiotics, azithromycin, and amoxicillin, in the human microbiome has not been thoroughly described. In this study, we recruited a group of individuals and unrelated controls to decipher the effects of the commonly used antibiotics amoxicillin and azithromycin on their gut microbiomes.
RESULTS
We characterized the gut microbiomes by metagenomic sequencing followed by characterization of the resulting microbial communities. We found that there were clear and sustained effects of the antibiotics on the gut microbial community with significant alterations in the representations of Bifidobacterium species in response to azithromycin (macrolide antibiotic). These results were supported by significant increases identified in putative antibiotic resistance genes associated with macrolide resistance. Importantly, we did not identify these trends in the unrelated control individuals. There were no significant changes observed in other members of the microbial community.
CONCLUSIONS
As we continue to focus on the role that the gut microbiome plays and how disturbances induced by antibiotics might affect our overall health, elucidating members of the community most affected by their use is of critical importance to understanding the impacts of common antibiotics on those who take them. Clinical Trial Registration Number NCT05169255. This trial was retrospectively registered on 23-12-2021.
Topics: Humans; Anti-Bacterial Agents; Amoxicillin; Azithromycin; Metagenomics; Macrolides; Drug Resistance, Bacterial
PubMed: 37528343
DOI: 10.1186/s12866-023-02949-z -
Current Opinion in Infectious Diseases Oct 2023The emergence of globally resistant enteric Shigella and nontyphoidal Salmonella strains (NTS) has limited the selection of effective drugs, which has become a major... (Review)
Review
PURPOSE OF REVIEW
The emergence of globally resistant enteric Shigella and nontyphoidal Salmonella strains (NTS) has limited the selection of effective drugs, which has become a major challenge for the treatment of infections. The purpose of this review is to provide the current opinion on the antimicrobial-resistant enteric Shigella and nontyphoidal Salmonella .
RECENT FINDINGS
Enteric Shigella and NTS are resistant to almost all classes of antimicrobials in recent years. Those with co-resistance to ciprofloxacin, azithromycin and ceftriaxone, the first-line antibiotics for the treatment of infectious diarrhoea have emerged worldwide. Some of them have caused interregional and international spread by travel, trade, MSM, and polluted water sources. Several strains have even developed resistance to colistin, the last-resort antibiotic used for treatment of multidrug-resistant Gram-negative bacteria infections.
SUMMARY
The drug resistance of enteric Shigella and NTS is largely driven by the use of antibiotics and horizontal gene transfer of mobile genetic elements. These two species show various drug resistance patterns in different regions and serotypes. Hence treatment decisions for Shigella and Salmonella infections need to take into consideration prevalent antimicrobial drug resistance patterns. It is worth noting that the resistance genes such as blaCTX,mph, ermB , qnr and mcr , which can cause resistance to ciprofloxacin, cephalosporin, azithromycin and colistin are widespread because of transmission by IncFII, IncI1, IncI2 and IncB/O/K/Z plasmids. Therefore, continuous global monitoring of resistance in Shigella and Salmonella is imperative.
Topics: Humans; Azithromycin; Colistin; Shigella; Salmonella; Anti-Bacterial Agents; Ciprofloxacin
PubMed: 37594001
DOI: 10.1097/QCO.0000000000000960 -
The Medical Clinics of North America Mar 2024Mycoplasma genitalium (MG) is an emerging sexually transmitted infection, which appears to be a cause of urethritis and cervicitis and has been associated with pelvic... (Review)
Review
Mycoplasma genitalium (MG) is an emerging sexually transmitted infection, which appears to be a cause of urethritis and cervicitis and has been associated with pelvic inflammatory disease (PID), epididymitis, proctitis, infertility, complications during pregnancy, and human immunodeficiency virus (HIV) transmission. Three Food and Drug Administration (FDA) approved tests are available. Testing should be focused to avoid inappropriate antibiotic use. The Center of Disease Control and Prevention (CDC) guidelines recommend testing for persistent male urethritis, cervicitis, and proctitis and state that testing should be considered in cases of PID. Testing is also recommended for sexual contacts of patients with MG. Testing is not recommended in asymptomatic patients, including pregnant patients, who do not have a history of MG exposure. Although resistance-guided therapy is recommended, there are currently no FDA approved tests for MG macrolide resistance, and tests are not widely available in the United States. The CDC recommends 2-step treatment with doxycycline followed by azithromycin or moxifloxacin. Moxifloxacin is recommended if resistance testing is unavailable or testing demonstrates macrolide resistance..
Topics: Pregnancy; Female; Humans; Male; Anti-Bacterial Agents; Urethritis; Mycoplasma genitalium; Moxifloxacin; Uterine Cervicitis; Macrolides; Mycoplasma Infections; Drug Resistance, Bacterial; Pelvic Inflammatory Disease; Proctitis; Primary Health Care
PubMed: 38331481
DOI: 10.1016/j.mcna.2023.07.004 -
The Journal of Maternal-fetal &... Dec 2024This study was aimed to investigate the serotypes, antibiotic susceptibilities, and multi-locus sequence type (MLST) profiles of group B (GBS) in the Beijing area.
OBJECTIVE
This study was aimed to investigate the serotypes, antibiotic susceptibilities, and multi-locus sequence type (MLST) profiles of group B (GBS) in the Beijing area.
METHODS
Lower vaginal and rectal swabs were obtained from pregnant women of 35-37 gestational weeks (GWs) who attended the Beijing Obstetrics and Gynecology Hospital. All GBS isolates were identified with Gram staining, catalase reaction assays, and CAMP tests, followed by antibiotic susceptibility testing, serotype identification, multilocus sequence typing and erythromycin resistance gene analysis ( and ).
RESULTS
From July 2020 to June 2022, 311 (5.17%) of 6012 pregnant women that were screened for GBS colonization were detected positive. Of the eight serotypes identified (III, Ia, Ib, IV, II, VIII, V, and NT), serotypes III (43.09%), Ia (34.08%) and Ib (17.04%) were the predominant species. In the antimicrobial susceptibility experiments, the resistant rates measured for erythromycin, clindamycin, levofloxacin, and tetracycline were 76.21%, 63.99%, 50.80%, and 81.03%, respectively, and 7.6% of GBS isolates showed inducible clindamycin in resistance (D-test phenotype). Meanwhile, the multilocus sequence typing analysis showed that sequence type 19 (ST19) (30.34%) and ST10 (18.62%) were the dominant sequence types. Among the 237 erythromycin-resistant isolates, 176 harbored (128, 54.00%) or (48, 20.30%) gene alone.
CONCLUSION
The infection rates, serotypes or MSLT distribution, and antimicrobial resistance of GBS in Beijing area were investigated, which may be applied in analyses of the epidemiological characteristics of GBS. This contributes to the basic knowledge required for successful GBS vaccine development suited for disease prevention and treatment in China, as well as the implementation of effective clinical antimicrobials.
Topics: Female; Humans; Pregnancy; Anti-Bacterial Agents; Serogroup; Pregnant Women; Clindamycin; Streptococcal Infections; Multilocus Sequence Typing; Drug Resistance, Bacterial; Erythromycin; Streptococcus agalactiae; China; Microbial Sensitivity Tests
PubMed: 38124302
DOI: 10.1080/14767058.2023.2295805 -
Epidemiology and Infection Apr 2024This paper retrospectively analysed the prevalence of macrolide-resistant (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145...
This paper retrospectively analysed the prevalence of macrolide-resistant (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.
Topics: Mycoplasma pneumoniae; Humans; China; Macrolides; Retrospective Studies; Child; Anti-Bacterial Agents; Drug Resistance, Bacterial; Child, Preschool; Adolescent; Adult; Female; Male; Pneumonia, Mycoplasma; Middle Aged; Young Adult; Microbial Sensitivity Tests; Aged; Infant; Prevalence; RNA, Ribosomal, 23S; Aged, 80 and over
PubMed: 38634450
DOI: 10.1017/S0950268824000323 -
World Journal of Microbiology &... Sep 2023A comparative analysis between water and sediment can provide better information to understand the dynamics of the inhabitant microbiome and their respective antibiotic...
A comparative analysis between water and sediment can provide better information to understand the dynamics of the inhabitant microbiome and their respective antibiotic resistance genes of a river. Therefore, the present investigation was carried to explore the limited information available on bacterial microbiome and their predictive antibiotic resistance genes (ARGs) from water and sediment of the Ganga River. The study utilized the NGS-based sequences previously submitted under the accession number (PRJNA847424 and PRJNA892876). Overall analysis revealed that twenty phyla and fifty-four genera were shared between the water and sediment of the Ganga River. Of them, nine phyla and nineteen genera were observed as significantly different (p-value < 0.05). Where the majority of the genera were associated with the sediment samples over the water that identify the sediment samples as more diverse for species richness. Similarly, seventy-six ARGs were shared between water and sediment samples. Of the ten abundant antibiotic resistance pathways, seven were relatively abundant in sediment samples as compared to the water. Vancomycin resistance genes were significantly more abundant among sediment samples, whereas β-lactam resistance genes were equally distributed in water and sediment samples. The network analysis further revealed that five genera (Flavobacterium, Pseudomonas, Acinetobacter, Candidatus_divison CL5003, and Candidatus_division SWB02) showed a significantly positive correlation with six antibiotic resistance pathways (β-lactam, vancomycin, multidrug resistance, tetracycline, aminoglycoside, and macrolide resistance pathways). The study comes out with several findings where sediment may be considered as a more atrocious habitat for evolving the resistance mechanisms against threatful antibiotics over the water samples of the Ganga River.
Topics: Anti-Bacterial Agents; Water; Rivers; Drug Resistance, Bacterial; Macrolides; Vancomycin; India
PubMed: 37656255
DOI: 10.1007/s11274-023-03730-0 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Aug 2023Tacrolimus (FK506) is a 23-membered macrolide with immunosuppressant activity that is widely used clinically for treating the rejection after organ transplantation. The... (Review)
Review
Tacrolimus (FK506) is a 23-membered macrolide with immunosuppressant activity that is widely used clinically for treating the rejection after organ transplantation. The research on tacrolimus production was mainly focused on biosynthesis methods, within which there are still some bottlenecks. This review summarizes the progress made in tacrolimus biosynthesis modification of metabolic pathways and control of fermentation process, with the hope to address the technical bottlenecks for tacrolimus biosynthesis and improve tacrolimus production by fermentation engineering and metabolic engineering.
Topics: Tacrolimus; Immunosuppressive Agents; Fermentation; Macrolides; Anti-Bacterial Agents
PubMed: 37622350
DOI: 10.13345/j.cjb.220994