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Molecules (Basel, Switzerland) Dec 2017Aminoglycosides are a group of antibiotics used since the 1940s to primarily treat a broad spectrum of bacterial infections. The primary resistance mechanism against... (Review)
Review
Aminoglycosides are a group of antibiotics used since the 1940s to primarily treat a broad spectrum of bacterial infections. The primary resistance mechanism against these antibiotics is enzymatic modification by aminoglycoside-modifying enzymes that are divided into acetyl-transferases, phosphotransferases, and nucleotidyltransferases. To overcome this problem, new semisynthetic aminoglycosides were developed in the 70s. The most widely used semisynthetic aminoglycoside is amikacin, which is refractory to most aminoglycoside modifying enzymes. Amikacin was synthesized by acylation with the l-(-)-γ-amino-α-hydroxybutyryl side chain at the C-1 amino group of the deoxystreptamine moiety of kanamycin A. The main amikacin resistance mechanism found in the clinics is acetylation by the aminoglycoside 6'--acetyltransferase type Ib [AAC(6')-Ib], an enzyme coded for by a gene found in integrons, transposons, plasmids, and chromosomes of Gram-negative bacteria. Numerous efforts are focused on finding strategies to neutralize the action of AAC(6')-Ib and extend the useful life of amikacin. Small molecules as well as complexes ionophore-Zn or Cu were found to inhibit the acetylation reaction and induced phenotypic conversion to susceptibility in bacteria harboring the gene. A new semisynthetic aminoglycoside, plazomicin, is in advance stage of development and will contribute to renewed interest in this kind of antibiotics.
Topics: Amikacin; Anti-Bacterial Agents; Bacterial Infections; Genes, Bacterial; Gram-Negative Bacteria; Humans; Kanamycin Resistance
PubMed: 29257114
DOI: 10.3390/molecules22122267 -
The Journal of Antimicrobial... Oct 2016The objectives of this study were to identify the amikacin dosage regimens and drug concentrations consistent with good outcomes and to determine the drug exposures... (Review)
Review
OBJECTIVES
The objectives of this study were to identify the amikacin dosage regimens and drug concentrations consistent with good outcomes and to determine the drug exposures related to nephrotoxicity and ototoxicity.
METHODS
A literature review was conducted in Medline, EMBASE and the Cochrane Central Register of Controlled Trials. Full journal articles reporting randomized controlled trials, controlled clinical trials, interrupted time series trials, and controlled before and after studies involving amikacin therapeutic drug monitoring (TDM) and dose adjustment were considered for inclusion.
RESULTS
Seventeen studies for inclusion were identified, comprising 1677 participants. Amikacin doses ranged from 11 to 15 mg/kg/day with 13 studies using 15 mg/kg/day. Studies were generally designed to compare different aminoglycosides rather than to assess concentration-effect relationships. Only 11 papers presented data on target concentrations, rate of clinical cure and toxicity. Target peak concentrations ranged from 15 to 40 mg/L and target troughs were typically <10 or <5 mg/L. It was not clear whether these targets were achieved. Measured peaks averaged 28 mg/L for twice-daily dosing and 40-45 mg/L for once-daily dosing; troughs averaged 5 and 1-2 mg/L, respectively. Fifteen of the included studies reported rates of nephrotoxicity; auditory and vestibular toxicities were reported in 12 and 8 studies.
CONCLUSIONS
This systematic review found little published evidence to support an optimal dosage regimen or TDM targets for amikacin therapy. The use of alternative approaches, such as consensus opinion and a review of current practice, will be required to develop guidelines to maximize therapeutic outcomes and minimize toxicity with amikacin.
Topics: Adult; Amikacin; Anti-Bacterial Agents; Dose-Response Relationship, Drug; Drug Monitoring; Drug-Related Side Effects and Adverse Reactions; Humans; Interrupted Time Series Analysis; Treatment Outcome
PubMed: 27494904
DOI: 10.1093/jac/dkw250 -
The Cochrane Database of Systematic... May 2022The World Health Organization (WHO) End TB Strategy stresses universal access to drug susceptibility testing (DST). DST determines whether Mycobacterium tuberculosis... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The World Health Organization (WHO) End TB Strategy stresses universal access to drug susceptibility testing (DST). DST determines whether Mycobacterium tuberculosis bacteria are susceptible or resistant to drugs. Xpert MTB/XDR is a rapid nucleic acid amplification test for detection of tuberculosis and drug resistance in one test suitable for use in peripheral and intermediate level laboratories. In specimens where tuberculosis is detected by Xpert MTB/XDR, Xpert MTB/XDR can also detect resistance to isoniazid, fluoroquinolones, ethionamide, and amikacin.
OBJECTIVES
To assess the diagnostic accuracy of Xpert MTB/XDR for pulmonary tuberculosis in people with presumptive pulmonary tuberculosis (having signs and symptoms suggestive of tuberculosis, including cough, fever, weight loss, night sweats). To assess the diagnostic accuracy of Xpert MTB/XDR for resistance to isoniazid, fluoroquinolones, ethionamide, and amikacin in people with tuberculosis detected by Xpert MTB/XDR, irrespective of rifampicin resistance (whether or not rifampicin resistance status was known) and with known rifampicin resistance.
SEARCH METHODS
We searched multiple databases to 23 September 2021. We limited searches to 2015 onwards as Xpert MTB/XDR was launched in 2020.
SELECTION CRITERIA
Diagnostic accuracy studies using sputum in adults with presumptive or confirmed pulmonary tuberculosis. Reference standards were culture (pulmonary tuberculosis detection); phenotypic DST (pDST), genotypic DST (gDST),composite (pDST and gDST) (drug resistance detection).
DATA COLLECTION AND ANALYSIS
Two review authors independently reviewed reports for eligibility and extracted data using a standardized form. For multicentre studies, we anticipated variability in the type and frequency of mutations associated with resistance to a given drug at the different centres and considered each centre as an independent study cohort for quality assessment and analysis. We assessed methodological quality with QUADAS-2, judging risk of bias separately for each target condition and reference standard. For pulmonary tuberculosis detection, owing to heterogeneity in participant characteristics and observed specificity estimates, we reported a range of sensitivity and specificity estimates and did not perform a meta-analysis. For drug resistance detection, we performed meta-analyses by reference standard using bivariate random-effects models. Using GRADE, we assessed certainty of evidence of Xpert MTB/XDR accuracy for detection of resistance to isoniazid and fluoroquinolones in people irrespective of rifampicin resistance and to ethionamide and amikacin in people with known rifampicin resistance, reflecting real-world situations. We used pDST, except for ethionamide resistance where we considered gDST a better reference standard.
MAIN RESULTS
We included two multicentre studies from high multidrug-resistant/rifampicin-resistant tuberculosis burden countries, reporting on six independent study cohorts, involving 1228 participants for pulmonary tuberculosis detection and 1141 participants for drug resistance detection. The proportion of participants with rifampicin resistance in the two studies was 47.9% and 80.9%. For tuberculosis detection, we judged high risk of bias for patient selection owing to selective recruitment. For ethionamide resistance detection, we judged high risk of bias for the reference standard, both pDST and gDST, though we considered gDST a better reference standard. Pulmonary tuberculosis detection - Xpert MTB/XDR sensitivity range, 98.3% (96.1 to 99.5) to 98.9% (96.2 to 99.9) and specificity range, 22.5% (14.3 to 32.6) to 100.0% (86.3 to 100.0); median prevalence of pulmonary tuberculosis 91.3%, (interquartile range, 89.3% to 91.8%), (2 studies; 1 study reported on 2 cohorts, 1228 participants; very low-certainty evidence, sensitivity and specificity). Drug resistance detection People irrespective of rifampicin resistance - Isoniazid resistance: Xpert MTB/XDR summary sensitivity and specificity (95% confidence interval (CI)) were 94.2% (87.5 to 97.4) and 98.5% (92.6 to 99.7) against pDST, (6 cohorts, 1083 participants, moderate-certainty evidence, sensitivity and specificity). - Fluoroquinolone resistance: Xpert MTB/XDR summary sensitivity and specificity were 93.2% (88.1 to 96.2) and 98.0% (90.8 to 99.6) against pDST, (6 cohorts, 1021 participants; high-certainty evidence, sensitivity; moderate-certainty evidence, specificity). People with known rifampicin resistance - Ethionamide resistance: Xpert MTB/XDR summary sensitivity and specificity were 98.0% (74.2 to 99.9) and 99.7% (83.5 to 100.0) against gDST, (4 cohorts, 434 participants; very low-certainty evidence, sensitivity and specificity). - Amikacin resistance: Xpert MTB/XDR summary sensitivity and specificity were 86.1% (75.0 to 92.7) and 98.9% (93.0 to 99.8) against pDST, (4 cohorts, 490 participants; low-certainty evidence, sensitivity; high-certainty evidence, specificity). Of 1000 people with pulmonary tuberculosis, detected as tuberculosis by Xpert MTB/XDR: - where 50 have isoniazid resistance, 61 would have an Xpert MTB/XDR result indicating isoniazid resistance: of these, 14/61 (23%) would not have isoniazid resistance (FP); 939 (of 1000 people) would have a result indicating the absence of isoniazid resistance: of these, 3/939 (0%) would have isoniazid resistance (FN). - where 50 have fluoroquinolone resistance, 66 would have an Xpert MTB/XDR result indicating fluoroquinolone resistance: of these, 19/66 (29%) would not have fluoroquinolone resistance (FP); 934 would have a result indicating the absence of fluoroquinolone resistance: of these, 3/934 (0%) would have fluoroquinolone resistance (FN). - where 300 have ethionamide resistance, 296 would have an Xpert MTB/XDR result indicating ethionamide resistance: of these, 2/296 (1%) would not have ethionamide resistance (FP); 704 would have a result indicating the absence of ethionamide resistance: of these, 6/704 (1%) would have ethionamide resistance (FN). - where 135 have amikacin resistance, 126 would have an Xpert MTB/XDR result indicating amikacin resistance: of these, 10/126 (8%) would not have amikacin resistance (FP); 874 would have a result indicating the absence of amikacin resistance: of these, 19/874 (2%) would have amikacin resistance (FN).
AUTHORS' CONCLUSIONS
Review findings suggest that, in people determined by Xpert MTB/XDR to be tuberculosis-positive, Xpert MTB/XDR provides accurate results for detection of isoniazid and fluoroquinolone resistance and can assist with selection of an optimised treatment regimen. Given that Xpert MTB/XDR targets a limited number of resistance variants in specific genes, the test may perform differently in different settings. Findings in this review should be interpreted with caution. Sensitivity for detection of ethionamide resistance was based only on Xpert MTB/XDR detection of mutations in the inhA promoter region, a known limitation. High risk of bias limits our confidence in Xpert MTB/XDR accuracy for pulmonary tuberculosis. Xpert MTB/XDR's impact will depend on its ability to detect tuberculosis (required for DST), prevalence of resistance to a given drug, health care infrastructure, and access to other tests.
Topics: Adult; Amikacin; Antibiotics, Antitubercular; Drug Resistance, Bacterial; Ethionamide; Fluoroquinolones; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Tuberculosis, Lymph Node; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary
PubMed: 35583175
DOI: 10.1002/14651858.CD014841.pub2 -
The Cochrane Database of Systematic... May 2021Neonatal sepsis is a major cause of morbidity and mortality. It is the third leading cause of neonatal mortality globally constituting 13% of overall neonatal mortality....
BACKGROUND
Neonatal sepsis is a major cause of morbidity and mortality. It is the third leading cause of neonatal mortality globally constituting 13% of overall neonatal mortality. Despite the high burden of neonatal sepsis, high-quality evidence in diagnosis and treatment is scarce. Due to the diagnostic challenges of sepsis and the relative immunosuppression of the newborn, many neonates receive antibiotics for suspected sepsis. Antibiotics have become the most used therapeutics in neonatal intensive care units, and observational studies in high-income countries suggest that 83% to 94% of newborns treated with antibiotics for suspected sepsis have negative blood cultures. The last Cochrane Review was updated in 2005. There is a need for an updated systematic review assessing the effects of different antibiotic regimens for late-onset neonatal sepsis.
OBJECTIVES
To assess the beneficial and harmful effects of different antibiotic regimens for late-onset neonatal sepsis.
SEARCH METHODS
We searched the following electronic databases: CENTRAL (2021, Issue 3); Ovid MEDLINE; Embase Ovid; CINAHL; LILACS; Science Citation Index EXPANDED and Conference Proceedings Citation Index - Science on 12 March 2021. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs.
SELECTION CRITERIA
We included RCTs comparing different antibiotic regimens for late-onset neonatal sepsis. We included participants older than 72 hours of life at randomisation, suspected or diagnosed with neonatal sepsis, meningitis, osteomyelitis, endocarditis, or necrotising enterocolitis. We excluded trials that assessed treatment of fungal infections.
DATA COLLECTION AND ANALYSIS
Three review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias. We used the GRADE approach to assess the certainty of evidence. Our primary outcome was all-cause mortality, and our secondary outcomes were: serious adverse events, respiratory support, circulatory support, nephrotoxicity, neurological developmental impairment, necrotising enterocolitis, and ototoxicity. Our primary time point of interest was at maximum follow-up.
MAIN RESULTS
We included five RCTs (580 participants). All trials were at high risk of bias, and had very low-certainty evidence. The five included trials assessed five different comparisons of antibiotics. We did not conduct a meta-analysis due to lack of relevant data. Of the five included trials one trial compared cefazolin plus amikacin with vancomycin plus amikacin; one trial compared ticarcillin plus clavulanic acid with flucloxacillin plus gentamicin; one trial compared cloxacillin plus amikacin with cefotaxime plus gentamicin; one trial compared meropenem with standard care (ampicillin plus gentamicin or cefotaxime plus gentamicin); and one trial compared vancomycin plus gentamicin with vancomycin plus aztreonam. None of the five comparisons found any evidence of a difference when assessing all-cause mortality, serious adverse events, circulatory support, nephrotoxicity, neurological developmental impairment, or necrotising enterocolitis; however, none of the trials were near an information size that could contribute significantly to the evidence of the comparative benefits and risks of any particular antibiotic regimen. None of the trials assessed respiratory support or ototoxicity. The benefits and harms of different antibiotic regimens remain unclear due to the lack of well-powered trials and the high risk of systematic errors.
AUTHORS' CONCLUSIONS
Current evidence is insufficient to support any antibiotic regimen being superior to another. RCTs assessing different antibiotic regimens in late-onset neonatal sepsis with low risks of bias are warranted.
Topics: Amikacin; Ampicillin; Anti-Bacterial Agents; Aztreonam; Bias; Cefazolin; Clavulanic Acid; Drug Therapy, Combination; Floxacillin; Gentamicins; Humans; Infant, Newborn; Neonatal Sepsis; Randomized Controlled Trials as Topic; Ticarcillin; Vancomycin
PubMed: 33998665
DOI: 10.1002/14651858.CD013836.pub2 -
Journal of Global Antimicrobial... Mar 2020The aim of this study was to describe antibiotic prescribing patterns and antimicrobial resistance rates in hospitalised children with febrile and afebrile urinary tract...
OBJECTIVES
The aim of this study was to describe antibiotic prescribing patterns and antimicrobial resistance rates in hospitalised children with febrile and afebrile urinary tract infections (UTIs).
METHODS
Antibiotic prescriptions and antibiograms for neonates, infants and older children with UTI admitted to a general district hospital in Central Greece were evaluated. Data covering a 5-year period were collected retrospectively from the Paediatric Department's Electronic Clinical Archive. Patients were included based on clinical and microbiological criteria. Antimicrobial susceptibility was determined by the Kirby-Bauer disk diffusion method.
RESULTS
A total of 230 patients were included in the study. Among 459 prescriptions identified, amikacin (31.2%) was the most common antibiotic prescribed in this population, followed by amoxicillin/clavulanic acid (17.4%) and ampicillin (13.5%). Children received prolonged intravenous (i.v.) treatments for febrile (mean ± S.D., 5.4 ± 1.45 days) and afebrile UTIs (mean ± S.D., 4.4 ± 1.64 days). A total of 236 pathogens were isolated. The main causative organism was Escherichia coli (79.2%) with high reported resistance rates to ampicillin (42.0%), trimethoprim/sulfamethoxazole (26.5%) and amoxicillin/clavulanic acid (12.2%); lower resistance rates were identified for third-generation cephalosporins (1.7%), nitrofurantoin (2.3%), ciprofloxacin (1.4%) and amikacin (0.9%). Klebsiella spp. isolates were highly resistant to cefaclor (27.3%).
CONCLUSION
High prescribing rates for amikacin and penicillins (± β-lactamase inhibitors) and prolonged i.v. treatments were observed. Escherichia coli was highly resistant to ampicillin, whilst third-generation cephalosporins exhibited greater in vitro efficacy. Establishment of antimicrobial stewardship programmes and regular monitoring of antimicrobial resistance could help to minimise inappropriate prescribing for UTIs.
Topics: Administration, Intravenous; Adolescent; Amikacin; Amoxicillin-Potassium Clavulanate Combination; Ampicillin; Anti-Bacterial Agents; Antimicrobial Stewardship; Child; Child, Preschool; Disk Diffusion Antimicrobial Tests; Drug Resistance, Multiple, Bacterial; Escherichia coli; Female; Fever; Greece; Humans; Infant; Infant, Newborn; Klebsiella; Male; Retrospective Studies; Urinary Tract Infections
PubMed: 31252156
DOI: 10.1016/j.jgar.2019.06.016 -
International Journal of Antimicrobial... May 2021The superiority of combination therapy for carbapenem-resistant Gram-negative bacilli (CR-GNB) infections remains controversial. In vitro models may predict the efficacy... (Meta-Analysis)
Meta-Analysis
The superiority of combination therapy for carbapenem-resistant Gram-negative bacilli (CR-GNB) infections remains controversial. In vitro models may predict the efficacy of antibiotic regimens against CR-GNB. A systematic review and meta-analysis was performed including pharmacokinetic/pharmacodynamic (PK/PD) and time-kill (TK) studies examining the in vitro efficacy of antibiotic combinations against CR-GNB [PROSPERO registration no. CRD42019128104]. The primary outcome was in vitro synergy based on the effect size (ES): high, ES ≥ 0.75, moderate, 0.35 < ES < 0.75; low, ES ≤ 0.35; and absent, ES = 0). A network meta-analysis assessed the bactericidal effect and re-growth rate (secondary outcomes). An adapted version of the ToxRTool was used for risk-of-bias assessment. Over 180 combination regimens from 136 studies were included. The most frequently analysed classes were polymyxins and carbapenems. Limited data were available for ceftazidime/avibactam, ceftolozane/tazobactam and imipenem/relebactam. High or moderate synergism was shown for polymyxin/rifampicin against Acinetobacter baumannii [ES = 0.91, 95% confidence interval (CI) 0.44-1.00], polymyxin/fosfomycin against Klebsiella pneumoniae (ES = 1.00, 95% CI 0.66-1.00) and imipenem/amikacin against Pseudomonas aeruginosa (ES = 1.00, 95% CI 0.21-1.00). Compared with monotherapy, increased bactericidal activity and lower re-growth rates were reported for colistin/fosfomycin and polymyxin/rifampicin in K. pneumoniae and for imipenem/amikacin or imipenem/tobramycin against P. aeruginosa. High quality was documented for 65% and 53% of PK/PD and TK studies, respectively. Well-designed in vitro studies should be encouraged to guide the selection of combination therapies in clinical trials and to improve the armamentarium against carbapenem-resistant bacteria.
Topics: Amikacin; Anti-Bacterial Agents; Azabicyclo Compounds; Carbapenems; Ceftazidime; Cephalosporins; Colistin; Drug Combinations; Drug Resistance, Bacterial; Drug Synergism; Drug Therapy, Combination; Fosfomycin; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Imipenem; In Vitro Techniques; Microbial Sensitivity Tests; Polymyxins; Rifampin; Tazobactam; Tobramycin
PubMed: 33857539
DOI: 10.1016/j.ijantimicag.2021.106344 -
Antimicrobial Agents and Chemotherapy Sep 2022Sulbactam-durlobactam is a β-lactam-β-lactamase inhibitor combination designed to treat serious Acinetobacter baumannii complex (ABC) infections, including...
Sulbactam-durlobactam is a β-lactam-β-lactamase inhibitor combination designed to treat serious Acinetobacter baumannii complex (ABC) infections, including carbapenem-non-susceptible and multidrug-resistant (MDR) isolates. The current study characterized the activity of sulbactam-durlobactam against a collection of 5,032 ABC clinical isolates collected in 33 countries across the Asia/South Pacific region, Europe, Latin America, the Middle East, and North America from 2016 to 2021. The sulbactam-durlobactam MIC and MIC were 1 and 2 μg/mL, respectively, for all ABC isolates tested. The addition of durlobactam (at a fixed concentration of 4 μg/mL) to sulbactam decreased its MIC by 8-fold (from 8 to 1 μg/mL) and its MIC by 32-fold (from 64 to 2 μg/mL) for all ABC isolates. The activity of sulbactam-durlobactam was maintained across individual ABC species, years, global regions of collection, specimen sources, and resistance phenotypes, including MDR and extensively drug-resistant (XDR) isolates. At 4 μg/mL (preliminary sulbactam-durlobactam susceptible MIC breakpoint), sulbactam-durlobactam inhibited 98.3% of all ABC isolates and >96% of sulbactam-, imipenem-, ciprofloxacin-, amikacin-, and minocycline-non-susceptible isolates; as well as colistin-resistant, MDR, and XDR isolates. Most imipenem-non-susceptible ABC isolates (96.8%, 2,488/2,570) were carbapenem-resistant A. baumannii (CRAB); 96.9% (2,410/2,488) of CRAB isolates were sulbactam-durlobactam-susceptible. More than 80% of ABC isolates had sulbactam-durlobactam MIC values that were ≥2 doubling-dilutions (4-fold) lower than sulbactam alone. Only 1.7% (84/5,032) of ABC isolates from 2016 to 2021 had sulbactam-durlobactam MIC values of >4 μg/mL. Of the 84 isolates, 94.0% were A. baumannii, 4.8% were A. pittii, and 1.2% were A. nosocomialis. In summary, sulbactam-durlobactam demonstrated potent antibacterial activity against a 2016 to 2021 collection of geographically diverse clinical isolates of ABC isolates, including carbapenem-non-susceptible and MDR isolates.
Topics: Acinetobacter Infections; Acinetobacter baumannii; Amikacin; Anti-Bacterial Agents; Azabicyclo Compounds; Carbapenems; Ciprofloxacin; Colistin; Drug Combinations; Humans; Imipenem; Microbial Sensitivity Tests; Minocycline; Sulbactam; beta-Lactamase Inhibitors
PubMed: 36005804
DOI: 10.1128/aac.00781-22 -
Antimicrobial Agents and Chemotherapy Aug 2019Multidrug-resistant (MDR) Gram-negative organisms are a major health concern due to lack of effective therapy. Emergence of resistance to newer agents like...
Evaluation of the Synergy of Ceftazidime-Avibactam in Combination with Meropenem, Amikacin, Aztreonam, Colistin, or Fosfomycin against Well-Characterized Multidrug-Resistant Klebsiella pneumoniae and Pseudomonas aeruginosa.
Multidrug-resistant (MDR) Gram-negative organisms are a major health concern due to lack of effective therapy. Emergence of resistance to newer agents like ceftazidime-avibactam (CZA) further magnifies the problem. In this context, combination therapy of CZA with other antimicrobials may have potential in treating these pathogens. Unfortunately, there are limited data regarding these combinations. Therefore, the objective of this study was to evaluate CZA in combination with amikacin (AMK), aztreonam (AZT), colistin (COL), fosfomycin (FOS), and meropenem (MEM) against 21 carbapenem-resistant and 21 MDR strains. The potential for synergy was evaluated via MIC combination evaluation and time-kill assays. All strains were further characterized by whole-genome sequencing, quantitative real-time PCR, and SDS-PAGE analysis to determine potential mechanisms of resistance. Compared to CZA alone, we observed a 4-fold decrease in CZA MICs for a majority of strains and at least a 2-fold decrease for most isolates in the majority of combinations tested. In both and strains, CZA in combination with AMK or AZT was synergistic (≥2.15-log CFU/ml decrease). CZA-MEM was effective against and CZA-FOS was effective against Time-kill analysis also revealed that the synergy of CZA with MEM or AZT may be due to the previously reported restoration of MEM or AZT activity against these organisms. Our findings show that CZA in combination with these antibiotics has potential for therapeutic options in difficult to treat pathogens. Further evaluation of these combinations is warranted.
Topics: Amikacin; Azabicyclo Compounds; Aztreonam; Ceftazidime; Colistin; Drug Combinations; Drug Resistance, Multiple, Bacterial; Drug Synergism; Fosfomycin; Klebsiella pneumoniae; Meropenem; Microbial Sensitivity Tests; Pseudomonas aeruginosa
PubMed: 31182535
DOI: 10.1128/AAC.00779-19 -
BMJ Open Sep 2021Pre-emptive inhaled antibiotics may be effective to reduce the occurrence of ventilator-associated pneumonia among critically ill patients. Meta-analysis of small sample...
INTRODUCTION
Pre-emptive inhaled antibiotics may be effective to reduce the occurrence of ventilator-associated pneumonia among critically ill patients. Meta-analysis of small sample size trials showed a favourable signal. Inhaled antibiotics are associated with a reduced emergence of antibiotic resistant bacteria. The aim of this trial is to evaluate the benefit of a 3-day course of inhaled antibiotics among patients undergoing invasive mechanical ventilation for more than 3 days on the occurrence of ventilator-associated pneumonia.
METHODS AND ANALYSIS
Academic, investigator-initiated, parallel two group arms, double-blind, multicentre superiority randomised controlled trial. Patients invasively ventilated more than 3 days will be randomised to receive 20 mg/kg inhaled amikacin daily for 3 days or inhaled placebo (0.9% Sodium Chloride). Occurrence of ventilator-associated pneumonia will be recorded based on a standardised diagnostic framework from randomisation to day 28 and adjudicated by a centralised blinded committee.
ETHICS AND DISSEMINATION
The protocol and amendments have been approved by the regional ethics review board and French competent authorities (Comité de protection des personnes Ouest I, No.2016-R29). All patients will be included after informed consent according to French law. Results will be disseminated in international scientific journals.
TRIAL REGISTRATION NUMBERS
EudraCT 2016-001054-17 and NCT03149640.
Topics: Administration, Inhalation; Amikacin; Double-Blind Method; Humans; Multicenter Studies as Topic; Pneumonia, Ventilator-Associated; Randomized Controlled Trials as Topic; Respiration, Artificial; Treatment Outcome
PubMed: 34521664
DOI: 10.1136/bmjopen-2020-048591 -
Clinical Microbiology and Infection :... Jun 2023For non-tuberculous mycobacteria (NTM), minimum inhibitory concentration (MIC) distributions of wild-type isolates have not been systematically evaluated despite their...
Towards clinical breakpoints for non-tuberculous mycobacteria - Determination of epidemiological cut off values for the Mycobacterium avium complex and Mycobacterium abscessus using broth microdilution.
OBJECTIVE
For non-tuberculous mycobacteria (NTM), minimum inhibitory concentration (MIC) distributions of wild-type isolates have not been systematically evaluated despite their importance for establishing antimicrobial susceptibility testing (AST) breakpoints.
METHODS
We gathered MIC distributions for drugs used against the Mycobacterium avium complex (MAC) and Mycobacterium abscessus (MAB) obtained by commercial broth microdilution (SLOMYCOI and RAPMYCOI) from 12 laboratories. Epidemiological cut-off values (ECOFFs) and tentative ECOFFs (TECOFFs) were determined by EUCAST methodology including quality control (QC) strains.
RESULTS
The clarithromycin ECOFF was 16 mg/L for M. avium (n = 1271) whereas TECOFFs were 8 mg/L for M. intracellulare (n = 415) and 1 mg/L for MAB (n = 1014) confirmed by analysing MAB subspecies without inducible macrolide resistance (n = 235). For amikacin, the ECOFFs were 64 mg/L for MAC and MAB. For moxifloxacin, the WT spanned >8 mg/L for both MAC and MAB. For linezolid, the ECOFF and TECOFF were 64 mg/L for M. avium and M. intracellulare, respectively. Current CLSI breakpoints for amikacin (16 mg/L), moxifloxacin (1 mg/L) and linezolid (8 mg/L) divided the corresponding WT distributions. For QC M. avium and M. peregrinum, ≥95% of MIC values were well within recommended QC ranges.
CONCLUSION
As a first step towards clinical breakpoints for NTM, (T)ECOFFs were defined for several antimicrobials against MAC and MAB. Broad wild-type MIC distributions indicate a need for further method refinement which is now under development within the EUCAST subcommittee for anti-mycobacterial drug susceptibility testing. In addition, we showed that several CLSI NTM breakpoints are not consistent in relation to the (T)ECOFFs.
Topics: Humans; Mycobacterium avium Complex; Anti-Bacterial Agents; Nontuberculous Mycobacteria; Amikacin; Mycobacterium abscessus; Moxifloxacin; Linezolid; Mycobacterium avium-intracellulare Infection; Microbial Sensitivity Tests; Drug Resistance, Bacterial; Macrolides; Mycobacterium tuberculosis; Mycobacterium Infections, Nontuberculous; Mycobacterium avium
PubMed: 36813087
DOI: 10.1016/j.cmi.2023.02.007