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Microbiology Spectrum Apr 2022This study aimed to evaluate whether trough level-guided monitoring can be replaced by area under the concentration-time curve (AUC) and MIC ratio-guided monitoring...
This study aimed to evaluate whether trough level-guided monitoring can be replaced by area under the concentration-time curve (AUC) and MIC ratio-guided monitoring (AUC/MIC ratio = 400) in patients infected with methicillin-resistant Staphylococcus aureus (MRSA) with a vancomycin MIC = 1 mg/L in Taiwan. In this retrospective study, patients treated with vancomycin for Methicillin-resistant Staphylococcus aureus (MRSA) infection were recruited from a teaching hospital in Taiwan from January 2016 to December 2017. Average trough concentrations were adjusted based on the average daily vancomycin dose, and the AUC/MIC ratio was calculated using the AUC/MIC conversion formula to analyze the correlation between trough or AUC/MIC ratio, nephrotoxicity, and clinical efficacy. As the primary outcome, the overall mean adjusted vancomycin average AUC/MIC ratio was 526.87 for a total of 102 patients. A total of 67% and 76% of the patients attained an AUC/MIC of ≥400 when the adjusted vancomycin trough concentrations were 10 to 15 mg/L and 15 to 20 mg/L, respectively. Additionally, 81.37% of the total study population had MRSA isolates with a vancomycin MIC of ≤1 mg/L. Moreover, in the subgroup, 92% of the patients attained an AUC/MIC of ≥400 on receiving vancomycin in the 10 to 15 mg/L trough range. An AUC/MIC of ≥400 was attained in patients infected with MRSA strains, who were treated by maintaining the vancomycin trough concentrations at 10 to 15 mg/L. Moreover, these patients demonstrated a lower incidence of nephrotoxicity. These findings support the use of the AUC/MIC ratio as a useful marker for the therapeutic monitoring of vancomycin owing to the clinical efficacy and safety of vancomycin in Taiwan. Since 2020, the Infectious Diseases Society of America (IDSA) updated vancomycin guidelines, and vancomycin AUC therapeutic drug monitor was updated to AUC/MIC in the United States. But acceptable rate of infection physicians in Taiwan was low. That is why this study evaluated in Taiwan.
Topics: Anti-Bacterial Agents; Humans; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Retrospective Studies; Staphylococcal Infections; Taiwan; Vancomycin
PubMed: 35412391
DOI: 10.1128/spectrum.01562-21 -
Clinical Microbiology and Infection :... Aug 2022Clostridioides difficile infections (CDI) are traditionally attributed to an older adult patient group but children can also be affected. Although the causative pathogen... (Review)
Review
BACKGROUND
Clostridioides difficile infections (CDI) are traditionally attributed to an older adult patient group but children can also be affected. Although the causative pathogen is the same in both populations, the management of CDI may differ.
OBJECTIVES
To discuss the current literature on CDI in the paediatric population and to provide CDI diagnostics and treatment guidance.
SOURCES
The literature was drawn from a search of PubMed from January 2017 to July 2021.
CONTENT
In the paediatric population, laboratory diagnostics for CDI should preferably be combined with laboratory diagnostics for other gastrointestinal pathogens. Coinfections of CDI are also possible. Though the detection of toxigenic C. difficile using a molecular assay may simply reflect colonisation rather than infection, detection of C. difficile free toxins A/B in faeces is much more indicative of true infection. CDI in children below 2 years of age and in the absence of risk factors is very difficult to diagnose and requires careful clinical judgement pending additional studies. Fidaxomicin has been shown to be superior to vancomycin with a sustained clinical response up to 30 days after the end of CDI treatment in children. Metronidazole is less effective than vancomycin in adults and there are no supporting data for its use in children. In recurrent CDI, treatment should be adjusted according to the drug or drug regimen used for the treatment of a previous episode(s). In multiple recurrent CDI, faecal microbiota transplantation can be effective.
IMPLICATIONS
If CDI laboratory testing is indicated in children with diarrhoea, the likelihood of C. difficile colonisation and coinfection with other intestinal pathogens should be considered. The currently available data support a change in the treatment strategy of CDI in children.
Topics: Aged; Anti-Bacterial Agents; Child; Clostridioides difficile; Clostridium Infections; Fidaxomicin; Humans; Vancomycin
PubMed: 35283312
DOI: 10.1016/j.cmi.2022.03.001 -
Current Biology : CB Aug 2023Antibiotic resistance often confers a fitness cost to the resistant cell and thus raises key questions of how resistance is maintained in the absence of antibiotics and,...
Antibiotic resistance often confers a fitness cost to the resistant cell and thus raises key questions of how resistance is maintained in the absence of antibiotics and, if lost, whether cells are genetically primed for re-evolving resistance. To address these questions, we have examined vancomycin-intermediate Staphylococcus aureus (VISA) strains that arise during vancomycin therapy. VISA strains harbor a broad spectrum of mutations, and they are known to be unstable both in patients and in the laboratory. Here, we show that loss of resistance in VISA strains is correlated with a fitness increase and is attributed to adaptive mutations, leaving the initial VISA-adaptive mutations intact. Importantly, upon a second exposure to vancomycin, such revertants evolve significantly faster to become VISA, and they reach higher resistance levels than vancomycin-naive cells. Further, we find that sub-lethal concentrations of vancomycin stabilize the VISA phenotype, as do the human β-defensin 3 (hBD-3) and the bacteriocin nisin that both, like vancomycin, bind to the peptidoglycan building block, lipid II. Thus, factors binding lipid II may stabilize VISA both in vivo and in vitro, and in case resistance is lost, mutations remain that predispose to resistance development. These findings may explain why VISA infections often are re-occurring and suggest that previous vancomycin adaptation should be considered a risk factor when deciding on antimicrobial chemotherapy.
Topics: Humans; Staphylococcus aureus; Vancomycin; Vancomycin Resistance; Anti-Bacterial Agents; Staphylococcal Infections
PubMed: 37494936
DOI: 10.1016/j.cub.2023.06.082 -
Antimicrobial Agents and Chemotherapy Apr 2022We determined optimal vancomycin starting dose regimens in infants ≤180 days of age to achieve the highest probability of target attainment with an area under the...
We determined optimal vancomycin starting dose regimens in infants ≤180 days of age to achieve the highest probability of target attainment with an area under the concentration-time curve for 24 h (AUC) of ≥400 using population pharmacokinetic (PK) modeling. Secondarily, determination of the relationship between serum creatinine (SCR) and vancomycin clearance in neonates was done. A retrospective population PK study was designed and included pediatric patients ≤180 days old who had received vancomycin and had a serum vancomycin concentration sampled. A population PK model was developed using Pumas (v1.0.5). Simulation was performed with various dosing regimens to evaluate the probability of AUC target attainment and probability of trough of ≤20 mg/liter, and comparison to published models was performed. Individual clearance estimates, obtained from the final model, were plotted against SCR and faceted by age quartiles to assess the relationship between SCR and vancomycin clearance. A total of 934 patients were included in the study (58.6% male; median age, 43.6 days [range of 0 to 184]; median number of concentration samples, 1 [range of 1 to 29]). A one-compartment model was developed with body weight (WT), SCR, and postmenstrual age (PMA) identified as significant covariates on clearance. Plotting vancomycin clearance versus SCR demonstrated no clear relationship between the two at <10 days postnatal age (PNA). Dosing regimens to attain AUC and trough targets were stratified according to SCR for ≥10 days PNA and PMA for <10 days PNA. A vancomycin population PK model was developed for pediatric patients <180 days of age incorporating WT, SCR, and PMA. The relationship between vancomycin clearance and serum creatinine is not clear at <10 days PNA.
Topics: Adult; Anti-Bacterial Agents; Body Weight; Child; Computer Simulation; Creatinine; Female; Humans; Infant; Infant, Newborn; Male; Retrospective Studies; Vancomycin
PubMed: 35293782
DOI: 10.1128/aac.01899-21 -
International Journal of Molecular... Nov 2023has emerged as a critical human pathogen, and a number of isolated reports have described the successful treatment of infections with vancomycin, a drug that is...
has emerged as a critical human pathogen, and a number of isolated reports have described the successful treatment of infections with vancomycin, a drug that is typically used to target Gram-positive bacteria. This study employed in vitro broth microdilution checkerboard and time-kill assays, as well as in vivo zebrafish animal models to evaluate the individual and combination antimicrobial effects of vancomycin and rifampin against . The minimum inhibitory concentration ranges of vancomycin and rifampin against 167 isolates of were 16-256 mg/L and 0.06-128 mg/L, respectively. The checkerboard assay results revealed a synergistic effect between vancomycin and rifampin in 16.8% (28/167) of the isolates. Time-kill assays were implemented for 66 isolates, and the two-drug combination had a synergistic interaction in 57 (86.4%) isolates. In vivo zebrafish studies revealed that treatment with vancomycin monotherapy, rifampin monotherapy, or vancomycin-rifampin combination therapy yielded a higher survival rate than the control group treatment with 0.9% saline. The results of this study support the use of vancomycin to treat infections.
Topics: Animals; Humans; Vancomycin; Rifampin; Anti-Bacterial Agents; Zebrafish; Microbial Sensitivity Tests
PubMed: 38069334
DOI: 10.3390/ijms242317012 -
Clinical Infectious Diseases : An... Mar 2023Antimicrobial susceptibility testing (AST) is not routinely performed for Clostridioides difficile and data evaluating minimum inhibitory concentrations (MICs) are...
BACKGROUND
Antimicrobial susceptibility testing (AST) is not routinely performed for Clostridioides difficile and data evaluating minimum inhibitory concentrations (MICs) are limited. We performed AST and whole genome sequencing (WGS) for 593 C. difficile isolates collected between 2012 and 2017 through the Centers for Disease Control and Prevention's Emerging Infections Program.
METHODS
MICs to 6 antimicrobial agents (ceftriaxone, clindamycin, meropenem, metronidazole, moxifloxacin, and vancomycin) were determined using the reference agar dilution method according to Clinical and Laboratory Standards Institute guidelines. Whole genome sequencing was performed on all isolates to detect the presence of genes or mutations previously associated with resistance.
RESULTS
Among all isolates, 98.5% displayed a vancomycin MIC ≤2 μg/mL and 97.3% displayed a metronidazole MIC ≤2 μg/mL. Ribotype 027 (RT027) isolates displayed higher vancomycin MICs (MIC50: 2 μg/mL; MIC90: 2 μg/mL) than non-RT027 isolates (MIC50: 0.5 μg/mL; MIC90: 1 μg/mL) (P < .01). No vanA/B genes were detected. RT027 isolates also showed higher MICs to clindamycin and moxifloxacin and were more likely to harbor associated resistance genes or mutations.
CONCLUSIONS
Elevated MICs to antibiotics used for treatment of C. difficile infection were rare, and there was no increase in MICs over time. The lack of vanA/B genes or mutations consistently associated with elevated vancomycin MICs suggests there are multifactorial mechanisms of resistance. Ongoing surveillance of C. difficile using reference AST and WGS to monitor MIC trends and the presence of antibiotic resistance mechanisms is essential.
Topics: Humans; United States; Vancomycin; Metronidazole; Clostridioides difficile; Clindamycin; Moxifloxacin; Clostridioides; Clostridium Infections; Anti-Bacterial Agents; Genomics; Microbial Sensitivity Tests; Ribotyping
PubMed: 36208202
DOI: 10.1093/cid/ciac817 -
Letters in Applied Microbiology Sep 2022Clostridium (Clostridioides) difficile infection (CDI) remains an urgent threat to patients in health systems worldwide. Recurrent CDI occurs in up to 30% of cases due... (Review)
Review
Clostridium (Clostridioides) difficile infection (CDI) remains an urgent threat to patients in health systems worldwide. Recurrent CDI occurs in up to 30% of cases due to sustained dysbiosis of the gut microbiota which normally protects against CDI. Associated costs of initial and recurrent episodes of CDI impose heavy financial burdens on health systems. Vancomycin and metronidazole have been the mainstay of therapy for CDI for many years; however, these agents continue to cause significant disruption to the gut microbiota and thus carry a high risk of recurrence for CDI patients. Treatment regimens are now turning towards novel narrow spectrum antimicrobial agents which target C. difficile while conserving the commensal gut microbiota, thus significantly reducing risk of recurrence. One such agent, fidaxomicin, has been in therapeutic use for several years and is now recommended as a first-line treatment for CDI, as it is superior to vancomycin in reducing risk of recurrence. Another narrow spectrum agent, ridnilazole, was recently developed and is undergoing evaluation of its potential clinical utility. This review aimed to summarize experimental reports of ridinilazole and assess its potential as a first-line agent for treatment of CDI. Reported results from in vitro assessments, and from hamster models of CDI, show potent activity against C. difficile, non-inferiority to vancomycin for clinical cure and non-susceptibility among most gut commensal bacteria. Phase I and II clinical trials have been completed with ridinilazole showing high tolerability and efficacy in treatment of CDI, and superiority over vancomycin in reducing recurrence of CDI within 30 days of treatment completion. Phase III trials are currently underway, the results of which may prove its potential to reduce recurrent CDI and lessen the heavy health and financial burden C. difficile imposes on patients and healthcare systems.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Benzimidazoles; Clostridioides; Clostridioides difficile; Clostridium; Clostridium Infections; Fidaxomicin; Humans; Metronidazole; Pyridines; Vancomycin
PubMed: 35119124
DOI: 10.1111/lam.13664 -
BMC Infectious Diseases Jan 2022Vancomycin-resistant enterococci (VRE) is the cause of severe patient health and monetary burdens. Antibiotic use is a confounding effect to predict VRE in patients, but...
BACKGROUND
Vancomycin-resistant enterococci (VRE) is the cause of severe patient health and monetary burdens. Antibiotic use is a confounding effect to predict VRE in patients, but the antibiotic use of patients who may have frequented the same ward as the patient in question is often neglected. This study investigates how patient movements between hospital wards and their antibiotic use can explain the colonisation of patients with VRE.
METHODS
Intrahospital patient movements, antibiotic use and PCR screening data were used from a hospital in the Netherlands. The PageRank algorithm was used to calculate two daily centrality measures based on the spatiotemporal graph to summarise the flow of patients and antibiotics at the ward level. A decision tree model was used to determine a simple set of rules to estimate the daily probability of patient VRE colonisation for each hospital ward. The model performance was improved using a random forest model and compared using 30% test sample.
RESULTS
Centrality covariates summarising the flow of patients and their antibiotic use between hospital wards can be used to predict the daily colonisation of VRE at the hospital ward level. The decision tree model produced a simple set of rules that can be used to determine the daily probability of patient VRE colonisation for each hospital ward. An acceptable area under the ROC curve (AUC) of 0.755 was achieved using the decision tree model and an excellent AUC of 0.883 by the random forest model on the test set. These results confirms that the random forest model performs better than a single decision tree for all levels of model sensitivity and specificity on data not used to estimate the models.
CONCLUSION
This study showed how the movements of patients inside hospitals and their use of antibiotics could predict the colonisation of patients with VRE at the ward level. Two daily centrality measures were proposed to summarise the flow of patients and antibiotics at the ward level. An early warning system for VRE can be developed to test and further develop infection prevention plans and outbreak strategies using these results.
Topics: Cross Infection; Gram-Positive Bacterial Infections; Humans; Vancomycin; Vancomycin Resistance; Vancomycin-Resistant Enterococci
PubMed: 35057734
DOI: 10.1186/s12879-022-07043-9 -
Scientific Reports Jan 2020Vancomycin, a branched tricyclic glycosylated peptide antibiotic, is a last-line defence against serious infections caused by staphylococci, enterococci and other...
Vancomycin, a branched tricyclic glycosylated peptide antibiotic, is a last-line defence against serious infections caused by staphylococci, enterococci and other Gram-positive bacteria. Orally-administered vancomycin is the drug of choice to treat pseudomembranous enterocolitis in the gastrointestinal tract. However, the risk of vancomycin-resistant enterococcal infection or colonization is significantly associated with oral vancomycin. Using the powerful matrix-free assay of co-sedimentation analytical ultracentrifugation, reinforced by dynamic light scattering and environmental scanning electron microscopy, and with porcine mucin as the model mucin system, this is the first study to demonstrate strong interactions between vancomycin and gastric and intestinal mucins, resulting in very large aggregates and depletion of macromolecular mucin and occurring at concentrations relevant to oral dosing. In the case of another mucin which has a much lower degree of glycosylation (~60%) - bovine submaxillary mucin - a weaker but still demonstrable interaction is observed. Our demonstration - for the first time - of complexation/depletion interactions for model mucin systems with vancomycin provides the basis for further study on the implications of complexation on glycopeptide transit in humans, antibiotic bioavailability for target inhibition, in situ generation of resistance and future development strategies for absorption of the antibiotic across the mucus barrier.
Topics: Animals; Anti-Bacterial Agents; Cattle; Gastrointestinal Tract; Mucins; Protein Aggregates; Protein Binding; Swine; Vancomycin
PubMed: 31969624
DOI: 10.1038/s41598-020-57776-3 -
BMC Health Services Research Jul 2023Currently, the detection rates of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) in the blood cultures of...
BACKGROUND AND OBJECTIVE
Currently, the detection rates of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) in the blood cultures of neonates with sepsis exceed the national average drug resistance level, and vancomycin and linezolid are the primary antibacterial drugs used for these resistant bacteria according to the results of etiological examinations. However, a comprehensive evaluation of their costs and benefits in late-onset neonatal sepsis in a neonatal intensive care unit (NICU) has not been conducted. This study aimed to compare the cost and effectiveness of vancomycin and linezolid in treating neonatal sepsis in the NICU.
METHODS
A cost-effectiveness analysis of real-world data was carried out by retrospective study in our hospital, and the cost and effectiveness of vancomycin and linezolid were compared by establishing a decision tree model. The drug doses in the model were 0.6 g for linezolid and 0.5 g for vancomycin. The cost break down included cost of medical ward, NICU stay, intravenous infusion of vancomycin or linezolid, all monitoring tests, culture tests and drugs. The unit costs were sourced from hospital information systems. The effectiveness rates were obtained by cumulative probability analysis. One-way sensitivity analysis was used to analyze uncertain influencing factors.
RESULTS
The effectiveness rates of vancomycin and linezolid in treating neonatal sepsis in the NICU were 89.74% and 90.14%, respectively, with no significant difference. The average cost in the vancomycin group was ¥12261.43, and the average cost in the linezolid group was ¥17227.96. The incremental cost effectiveness was ¥12416.33 cost per additional neonate with treatment success in the linezolid group compared to vancomycin group at discharge. Factors that had the greatest influence on the sensitivity of the incremental cost-effectiveness ratio were the price of linezolid and the effectiveness rates.
CONCLUSIONS
The cost for treatment success of one neonate in linezolid group was ¥5449.17 more than that in vancomycin group, indicating that vancomycin was more cost-effective. Therefore, these results can provide a reference for a cost effectiveness treatment scheme for neonatal sepsis in the NICU.
Topics: Vancomycin; Linezolid; Anti-Bacterial Agents; Neonatal Sepsis; Cost-Effectiveness Analysis; Humans; Methicillin-Resistant Staphylococcus aureus; Male; Female; Infant; Coagulase; Retrospective Studies; Drug Costs; Treatment Outcome; China
PubMed: 37468855
DOI: 10.1186/s12913-023-09628-9