The impact of the coronavirus disease (COVID-19) pandemic on antimicrobial resistance (AMR) is a major concern.
To compare the number of patients and isolation rate of antimicrobial-resistant ...bacteria before and after the beginning of the COVID-19 pandemic using the comprehensive national surveillance data.
We utilized comprehensive surveillance data, collected in the Japan Nosocomial Infections Surveillance programme, which included a total of 16.7 million samples of 5.9 million tested patients from >1300 hospitals. We compared the number of patients and isolation rate of five bacteria between 2019 and 2020, including antimicrobial-susceptible and -resistant bacteria of Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa.
The number of patients and isolation rate of S. aureus and meticillin-resistant S. aureus decreased slightly; those of S. pneumoniae and penicillin-resistant S. pneumoniae decreased by 60%; and those of third-generation cephalosporin-resistant K. pneumoniae increased. The isolation rate of the remaining bacteria apparently increased, although the number of patients decreased. This was due to a substantial decrease in the total number of tested patients (the denominator of the isolation rate), which was larger than that of the number of patients (the numerator of the isolation rate). Consistent results were obtained when the same data were re-aggregated using the procedure of the World Health Organization Global Antimicrobial Resistance Surveillance System, demonstrating the general importance of this problem.
Surveillance data during the COVID-19 pandemic must be carefully interpreted based on examination of the numerator, denominator and background factors that affect the denominator.
We sought to optimize a method for quantification of the calcium in the aortic-valvar complex for the prediction of significant paravalvular leak (PVL) after transcatheter aortic valve implantation ...(TAVI).
All patients had severe symptomatic aortic stenosis and were treated with balloon-expandable TAVI (Sapien/Sapien-XT, Edwards Lifesciences LLC, Irvine, CA, USA). In order to correct for precise annular sizing, only patients with available contrast computed tomography (CT) data for measurements were included (n = 198). Paravalvular leak was quantified using peri-procedural transoesophageal echocardiography by Valve Academic Research Consortium-2 (VARC-2) criteria (grade ≥ moderate was considered significant). A detailed region-of-interest methodology separated quantification of calcium in each of the aortic leaflets to that in the left ventricular outflow tract (LVOT) and was used to predict PVL in receiver operator characteristic curve analyses. For non-contrast scans, the greatest discriminatory value for PVL was seen at the 450 Hounsfield Unit (HU) threshold for detection (volume ≥626 mm(3)), whereas for contrast scans it was at 850 HU (≥235 mm(3)). Left ventricular outflow tract calcium predicted PVL but only as a binary variable with no incremental value of quantification. In a multivariable binary logistic regression model, annulus area ≥ prosthesis area (OR 3.5, 95% CI 1.5-8.2, P = 0.005), contrast leaflet calcium volume (850-HU threshold) ≥235 mm(3) (OR 2.8, 95% CI 1.2-6.7, P = 0.023), and presence of LVOT calcium (OR 2.8, 95% CI 1.2-7.0, P = 0.022) were independent predictors for PVL ≥ moderate.
Both leaflet and LVOT calcium are significant predictors of PVL and exert an important synergistic influence on this complication, even in appropriately sized valves. With careful attention to thresholds for detection, clinically relevant leaflet calcium volumes can be identified with either non-contrast or contrast CT scans.
Antimicrobial resistance in Staphylococcus aureus imposes a high disease burden. Both phenotypic and genotypic monitoring are key to understanding and containing emerging resistant strains.
...Phenotypic monitoring of emerging resistance in S. aureus and correlation of priority strain phenotypes with whole-genome sequencing (WGS) findings.
Antimicrobial susceptibility test results of >40,000 isolates from 213 participating hospitals from 2011 to 2019 were exported from the national Japan Nosocomial Infections Surveillance (JANIS) database. Longitudinal and geographic distribution and prevalence of distinct multi-drug resistance phenotypes (‘resistance profiles’) of S. aureus were examined among hospitals and prefectures. We further conducted a genome sequence analysis of strains with specific resistance profiles of concern.
The overall prevalence of meticillin-resistant S. aureus (MRSA) decreased from 40.3% to 35.1% from 2011 to 2019. However, among dozens of S. aureus resistance profiles, only one profile of a type of MRSA, exhibited a statistically significant increase in inpatient frequency, exceeding 10% during the nine years. This MRSA profile showed resistance to oxacillin, erythromycin and levofloxacin. Analysis of WGS results of S. aureus isolates with this phenotype revealed that most belonged to clonal complex 8, and all carried SCCmec IV, typical of community-acquired MRSA.
Tracking distinct resistance profiles deepened our understanding of the overall decrease in MRSA and led to recognition of the emergence of a new resistance phenotype. This study provides a model for future epidemiological research on antimicrobial resistance correlating multi-drug resistance phenotypes with selective genome sequencing, which can be applied to other bacterial species.
Summary Background Nosocomial infections caused by Acinetobacter baumannii international clone II (IC II) can cause severe clinical outcomes. Aim Differential evaluation of bactericidal efficacy of ...chlorhexidine gluconate (CHX) and benzethonium chloride (BZT) disinfectants against IC II and non-IC II isolates. Methods Minimum inhibitory concentrations (MICs) of CHX and BZT were determined for 137 A. baumannii IC II, 99 non-IC II and 69 non- baumannii isolates, further classified according to MIC values into disinfectant-reduced susceptible (DRS) and disinfectant-susceptible (DS) groups. Time-kill curves and minimum bactericidal concentrations (MBCs) were evaluated for representative isolates in each group. Results CHX and BZT MIC90 s for IC II isolates were 100 and 175 mg/L, respectively, but those for non-IC II and non- baumannii isolates were <100 mg/L. Nevertheless, time-kill curves indicated that CHX and BZT reduced live bacterial cell number by 5 log10 for IC II and non-IC II isolates within 30 s when used at 1000 mg/L, comparable to practical use concentrations. CHX MBC at 30 s was 1000 mg/L for IC II and non-IC II isolates, and was not influenced by addition of 3% bovine serum albumin (BSA); BZT MBC at 30 s was 100 mg/L without BSA and increased up to 500 mg/L upon addition of BSA. No significant differences in BSA were found between DRS and DS isolates. Conclusion CHX and BZT were effective against Acinetobacter spp. including IC II at a concentration of 1000 mg/L and exposure for at least 30 s, but their concentrations should be considered carefully to ensure sufficient effects in both clinical and healthcare settings.
This study sought to monitor the presence of carbapenem-resistant Enterobacteriaceae (CRE) and the proportion New Delhi metallo-beta-lactamase 1 (NDM-1)-producing bacteria between August 2010 and ...December 2012 in a surgical hospital in Vietnam. We identified 47 CRE strains from a total of 4,096 Enterobacteriaceae isolates (1.1 %) that were NDM-1-positive from 45 patients admitted to 11 different departments, with the majority being from the urology department. The NDM-1 gene was found in seven different species. Genotyping revealed limited clonality of NDM-1-positive isolates. Most of the isolates carried the NDM-1 gene on a plasmid and 17.8 % (8/45) of those were readily transferable. We found five patients at admission and one patient at discharge with NDM-1-positive bacteria in their stool. From 200 screening environmental hospital samples, five were confirmed to be NDM-1-positive and included
Acinetobacter
species (
n
= 3) and
Enterobacter aerogenes
(
n
= 2). The results reveal that NDM-1-producing Enterobacteriaceae are commonly isolated in patients admitted to a Vietnamese surgical hospital and are also detected in the hospital environment.
Acinetobacter baumannii
is an important cause of multidrug-resistant hospital acquired infections in the world. Here, we investigate the presence of NDM-1 and other carbapenemases among ...carbapenem-resistant
A. baumannii
isolated between August 2010 and December 2014 from three large hospitals in Hanoi, Vietnam. We identified 23/582 isolates (4 %) (11 from hospital A, five from hospital B, and seven from hospital C) that were NDM-1 positive, and among them 18 carried additional carbapenemase genes, including seven isolates carrying NDM-1, IMP-1, and OXA-58 with high MICs for carbapenems. Genotyping indicated that NDM-1 carrying
A. baumannii
have expanded clonally in these hospitals. Five new STs (ST1135, ST1136, ST1137, ST1138, and ST1139) were identified. One isolate carried NDM-1 on a plasmid belonging to the N-repA replicon type; no NDM-1-positive plasmids were identified in the other isolates. We have shown the extent of the carbapenem resistance and the local clonal spread of
A. baumannii
carrying NDM-1 in these hospitals; coexistence of NDM-1 and IMP-1 is reported for the first time from Vietnam here, and this will further seriously limit future therapeutic options.
Although several clinical variables are associated with the recurrence of atrial fibrillation (AF) following catheter ablation, the influence of renal function remains to be determined.
To evaluate ...the association of renal function with the outcome of the paroxysmal AF ablation.
224 patients underwent catheter ablation for paroxysmal AF. The relationship between the pre-procedural clinical valuables and ablation outcomes was evaluated.
Over the course of 37.4±24.4 months of follow-up of catheter ablation procedures for AF (mean number of procedures 1.33±0.45), 91.1% of patients (204/224) became free from AF without antiarrhythmic drugs. The estimated glomerular filtration rate (eGFR) was lower in patients with recurrent AF than in those without recurrence (66.6±17.5 vs 78.4±16.8 ml/min/1.73 m(2), p=0.003). AF recurred more frequently in patients with low eGFR (<60 ml/min/1.73 m(2)) than in those with high eGFR (>60 ml/min/1.73 m(2); 24.3% vs 6.7%, p=0.006). Among the various clinical factors, low eGFR (p=0.02) and left atrium (LA) dilatation (p=0.002) independently predicted the clinical outcome of ablation in patients with paroxysmal AF.
Low eGFR and LA dilatation independently influence the outcome of catheter ablation for paroxysmal AF.
Our institute has constructed a new treatment facility for carbon ion scanning beam therapy. The first clinical trials were successfully completed at the end of November 2011. To evaluate patient ...setup accuracy, positional errors between the reference Computed Tomography (CT) scan and final patient setup images were calculated using 2D-3D registration software. Eleven patients with tumors of the head and neck, prostate and pelvis receiving carbon ion scanning beam treatment participated. The patient setup process takes orthogonal X-ray flat panel detector (FPD) images and the therapists adjust the patient table position in six degrees of freedom to register the reference position by manual or auto- (or both) registration functions. We calculated residual positional errors with the 2D-3D auto-registration function using the final patient setup orthogonal FPD images and treatment planning CT data. Residual error averaged over all patients in each fraction decreased from the initial to the last treatment fraction 1.09 mm/0.76° (averaged in the 1st and 2nd fractions) to 0.77 mm/0.61° (averaged in the 15th and 16th fractions). 2D-3D registration calculation time was 8.0 s on average throughout the treatment course. Residual errors in translation and rotation averaged over all patients as a function of date decreased with the passage of time (1.6 mm/1.2° in May 2011 to 0.4 mm/0.2° in December 2011). This retrospective residual positional error analysis shows that the accuracy of patient setup during the first clinical trials of carbon ion beam scanning therapy was good and improved with increasing therapist experience.
We assessed the impact of changes in patient position on carbon-ion scanning beam distribution during treatment for prostate cancer.
68 patients were selected. Carbon-ion scanning dose was ...calculated. Two different planning target volumes (PTVs) were defined: PTV1 was the clinical target volume plus a set-up margin for the anterior/lateral sides and posterior side, while PTV2 was the same as PTV1 minus the posterior side. Total prescribed doses of 34.4 Gy relative biological effectiveness (RBE) and 17.2 Gy (RBE) were given to PTV1 and PTV2, respectively. To estimate the influence of geometric variations on dose distribution, the dose was recalculated on the rigidly shifted single planning CT based on two dimensional-three dimensional rigid registration of the orthogonal radiographs before and after treatment for the fraction of maximum positional changes.
Intrafractional patient positional change values averaged over all patients throughout the treatment course were less than the target registration error = 2.00 mm and angular error = 1.27°. However, these maximum positional errors did not occur in all 12 treatment fractions. Even though large positional changes occurred during irradiation in all treatment fractions, lowest dose encompassing 95% of the target (D95)-PTV1 was >98% of the prescribed dose.
Intrafractional patient positional changes occurred during treatment beam irradiation and degraded carbon-ion beam dose distribution. Our evaluation did not consider non-rigid deformations, however, dose distribution was still within clinically acceptable levels.
Inter- and intrafractional changes did not affect carbon-ion beam prostate treatment accuracy.
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