Antimicrobial Resistance Patterns of Common Gram-Negative Microorganisms Isolated from Patients with Lower Respiratory Tract Infections in a Teaching Hospital in Vietnam.

This cross-sectional study investigated the antimicrobial resistance (AMR) patterns of gram-negative pathogens isolated from 4,789 hospitalized patients with lower respiratory tract infections (LRTIs). Of the collected specimens, 1,325 (27.7%) tested positive for gram-negative bacteria. Acinetobacter baumannii (38.6%), Pseudomonas aeruginosa (33.5%), Klebsiella pneumoniae (18.7%), Escherichia coli (5.6%), and Klebsiella aerogenes (3.5%) were the most prevalent isolates. AMR analysis revealed high resistance rates (79.9%-100%) of A. baumannii isolates to multiple classes of antibiotics except amikacin, trimethoprim/sulfamethoxazole, and colistin. P. aeruginosa displayed low resistance to colistin (< 10%) but high resistance to other antibiotics. K. pneumoniae displayed high resistance rates of 90.0%-100.0% to most penicillins, whereas resistance rates were notably lower for colistin (7.1%) and amikacin (16.7%). K. aerogenes exhibited high resistance to various antibiotics and sensitivity to amikacin (95.1%), ampicillin (100.0%), and colistin (100.0%). E. coli isolates exhibited resistance to ampicillin (96.9%) and maximum sensitivity to several antibiotics. Our study identified significant AMR trends and highlighted the prevalence of multidrug-resistant strains (93.6% for K. aerogenes and 69.1%-92.4% for other isolates). These findings emphasize the urgent need for appropriate antibiotic management practices to combat AMR in gram-negative pathogens associated with LRTIs.

Efficacy and safety of zero-fluoroscopy ablation of ventricular arrhythmias originating from the right ventricular outflow tract: Comparison with fluoroscopy-guided ablation without a three-dimensional electroanatomic mapping system.

Background: Radiofrequency catheter ablation is the preferred treatment choice for ventricular arrhythmias (VAs) originating from right ventricular outflow tract (RVOT) in symptomatic patients and is usually performed under fluoroscopy guidance. Zero-fluoroscopy (ZF) ablations using 3D mapping system applied for treatment of various types of arrhythmias are trending and practiced in many centers around the world, but rarely done in Vietnam. The objective of this study was to evaluate the efficacy and safety of zero-fluoroscopy ablation of RVOT VAs, compared with fluoroscopy-guided ablation without a 3D electroanatomic mapping (EAM) system. Methods and Results: We conducted a nonrandomized, prospective single-center study including 114 patients with RVOT VAs that had electrocardiographic features of typical left bundle branch block, inferior axis QRS morphology, and a precordial transition ≥ V3, from May 2020 to July 2022. The patients were assigned (without randomization) to two different approaches of either zero-fluoroscopy ablation under the guidance of the Ensite system (ZF group) or fluoroscopy-guided ablation without a 3D EAM (fluoroscopy group) in a 1:1 ratio. After a follow-up time of 5.0 ± 4.9 months and 6.9 ± 9.3 months in the ZF and fluoroscopy groups, respectively, the results showed a higher success rate in the fluoroscopy group than in the complete ZF group (87.3% vs 86.8%), although the difference was not statistically significant. No major complication was noted in both the groups. Conclusion: ZF ablation for RVOT VAs can be done safely and effectively using the 3D electroanatomic mapping system. The results of ZF approach are comparable to that of the fluoroscopy-guided approach without a 3D EAM system.

Development of a new biochemical test to diagnose and monitor neuroblastoma in Vietnam: homovanillic and vanillylmandelic acid by gas chromatography-mass spectrometry.

OBJECTIVES: The aim of this study was to develop an accurate robust testing method to simultaneously measure urine levels of HVA and VMA using gas chromatography mass spectrometry (GCMS) and to establish age-specific reference intervals of HVA and VMA in random urines for Vietnamese children. DESIGN AND METHODS: The assay for urinary HVA and VMA was developed based on a classical urinary organic acid profiling method. Briefly, this incorporated 3-phenyl butyric acid as the internal standard and liquid-liquid extraction with ethyl acetate followed by derivatization with BSTFA. The Agilent 7890A GC and 5975C Mass Selective Detector in single ion monitoring mode was used for analysis. Reference intervals were developed from random urine samples collected from 634 disease free Vietnamese children and compared to 50 known neuroblastoma patient samples. Results were reported relative to creatinine concentration. Age related 95% reference intervals for urinary HVA and VMA were estimated from sample quantiles. The analytes (expressed as analyte/creatinine ratios) diagnostic values were determined by calculating the related sensitivity, specificity and likelihood ratios. RESULTS: HVA and VMA were linear to at least 193 and 221µmol/L, respectively. The limit of quantitation for both analytes was 0.9µmol/L. Using the bi-level control (n=15), the within-batch coefficients of variations (CVs) were less than 3% for both analytes across the assay range. The between-batch CVs (n=20 over three months), were 3.6% at 11µmol/L and 2.1% at 88µmol/L for HVA, 6.6% at 18.2µmol/L and 2.6% at 90.6µmol/L for VMA. Vietnamese age related reference intervals were established for urinary HVA and VMA per creatinine. HVA for children <6months (n=91) was 5.3-37.0µmol/mmol; 6months to <1year (n=141) was 2.7-27.7µmol/mmol; 1 to 5years (n=139) was 3.4-17.9µmol/mmol; 6 to 10years (n=136) was 2.7-8.8µmol/mmol; and 11 to 15years (n=127) was 1.1-9.4µmol/mmol. VMA for children <6months was 1.8-12.2µmol/mmol; 6months to <1year was 1.5-9.3µmol/mmol; 1 to 5years was 1.9-7.8µmol/mmol; 6 to 10years was 1.6-5.1µmol/mmol; and 11 to 15years was <0.9-6.3µmol/mmol. CONCLUSIONS: A robust testing method for simultaneous quantitation of urinary HVA and VMA by GCMS was developed. This method is accurate, precise and fit for its clinical purpose and suitable for developing countries. Age-related reference intervals of urinary HVA and VMA were established for Vietnamese children and the intervals declined progressively with increasing age for each analyte.