Antimicrobial Resistance Patterns of Staphylococcus Aureus Isolated at a General Hospital in Vietnam Between 2014 and 2021.

Purpose: Staphylococcus aureus is a commensal bacteria species that can cause various illnesses, from mild skin infections to severe diseases, such as bacteremia. The distribution and antimicrobial resistance (AMR) pattern of S. aureus varies by population, time, geographic location, and hospital wards. In this study, we elucidated the epidemiology and AMR patterns of S. aureus isolated from a general hospital in Vietnam. Methods: This was a cross-sectional study. Data on all S. aureus infections from 2014 to 2021 were collected from the Microbiology department of Military Hospital 103, Vietnam. Only the first isolation from each kind of specimen from a particular patient was analyzed using the Cochran-Armitage and chi-square tests. Results: A total of 1130 individuals were diagnosed as S. aureus infection. Among them, 1087 strains were tested for AMR features. Most patients with S. aureus infection were in the age group of 41-65 years (39.82%). S. aureus isolates were predominant in the surgery wards, and pus specimens were the most common source of isolates (50.62%). S. aureus was most resistant to azithromycin (82.28%), erythromycin (82.82%), and clindamycin (82.32%) and least resistant to teicoplanin (0.0%), tigecycline (0.16%), quinupristin-dalfopristin (0.43%), linezolid (0.62%), and vancomycin (2.92%). Methicillin-resistant S. aureus (MRSA) and multidrug-resistant (MDR) S. aureus were prevalent, accounting for 73.02% and 60.90% of the total strains respectively, and the strains isolated from the intensive care unit (ICU) had the highest percentage of multidrug resistance (77.78%) among the wards. Conclusion: These findings highlight the urgent need for continuous AMR surveillance and updated treatment guidelines, particularly considering high resistance in MRSA, MDR strains, and ICU isolates. Future research focusing on specific resistant populations and potential intervention strategies is crucial to combat this rising threat.

Distribution and Antibiotic Resistance Characteristics of Bacteria Isolated from Blood Culture in a Teaching Hospital in Vietnam During 2014-2021.

Purpose: Studies on the epidemiology of bloodstream infection (BSI) and antimicrobial resistance (AMR) are limited in Vietnam. Thus, the present study aimed to elucidate the epidemiology of BSI and AMR of BSI-causing bacteria in Vietnam. Methods: Data regarding blood cultures from 2014 to 2021 were collected and analyzed using the chi-square test, Cochran-Armitage test, and binomial logistic regression model. Results: Overall, 2405 (14.15%) blood cultures were positive during the study period. In total, 55.76% of BSIs occurred in patients aged ≥60 years. The male-to-female ratio of patients with BSI was 1.87:1. Escherichia coli (26.11%), Staphylococcus aureus (15.79%), Klebsiella pneumoniae (10.44%), Acinetobacter baumannii (4.70%), and Pseudomonas aeruginosa (3.45%) were the leading bacterial species causing BSI. The AMR rate of these bacteria isolated in the intensive care unit (ICU) was significantly higher compared with that of those in other wards. E. coli was the least resistant to carbapenems (2.39%-4.14%), amikacin (3.85%), and colistin (11.54%) and most resistant to penicillins (>80.0%). S. aureus was the least resistant to glycopeptides (0%-3.38%), quinupristin-dalfopristin (0.59%), and linezolid (1.02%) and most resistant to clindamycin (71.57%). K. pneumoniae was the least resistant to ertapenem (8.86%), amikacin (9.39%), and colistin (15.38%) and most resistant to aztreonam (83.33%). A. baumannii was the least resistant to amikacin (16.67%) and colistin (16.67%) and highly resistant to other antibiotics (≥50.0%). P. aeruginosa was the least resistant to colistin (16.33%) and piperacillin (28.17%) and highly resistant to other antibiotics (≥50.0%). Notably, the multidrug resistance rate of E. coli (76.41%) was the highest among common pathogens, followed by A. baumannii (71.57%), P. aeruginosa (64.56%), S. aureus (56.99%), and K. pneumoniae (43.72%). Conclusion: The AMR rate of BSI-causing bacteria, particularly strains isolated from ICU, was alarmingly high. There is a need for new antibiotics, therapeutic strategies, as well as prevention and control to combat BSI and AMR.

Genetic Mapping of Multiple Traits Identifies Novel Genes for Adiposity, Lipids, and Insulin Secretory Capacity in Outbred Rats.

Despite the successes of human genome-wide association studies, the causal genes underlying most metabolic traits remain unclear. We used outbred heterogeneous stock (HS) rats, coupled with expression data and mediation analysis, to identify quantitative trait loci (QTLs) and candidate gene mediators for adiposity, glucose tolerance, serum lipids, and other metabolic traits. Physiological traits were measured in 1,519 male HS rats, with liver and adipose transcriptomes measured in >410 rats. Genotypes were imputed from low-coverage whole-genome sequencing. Linear mixed models were used to detect physiological and expression QTLs (pQTLs and eQTLs, respectively), using both single nucleotide polymorphism (SNP)- and haplotype-based models for pQTL mapping. Genes with cis-eQTLs that overlapped pQTLs were assessed as causal candidates through mediation analysis. We identified 14 SNP-based pQTLs and 19 haplotype-based pQTLs, of which 10 were in common. Using mediation, we identified the following genes as candidate mediators of pQTLs: Grk5 for fat pad weight and serum triglyceride pQTLs on Chr1, Krtcap3 for fat pad weight and serum triglyceride pQTLs on Chr6, Ilrun for a fat pad weight pQTL on Chr20, and Rfx6 for a whole pancreatic insulin content pQTL on Chr20. Furthermore, we verified Grk5 and Ktrcap3 using gene knockdown/out models, thereby shedding light on novel regulators of obesity.

Antiretroviral drug resistance mutations among patients failing first-line treatment in Hanoi, Vietnam.

Objectives: To study the prevalence of drug resistance and genotype testing for HIV drug resistance on HIV/AIDS patients with first-line antiretroviral treatment failure at Dong Da Hospital, Hanoi, Vietnam. Patients and methods: Forty-seven patients in Dong Da Hospital, Hanoi, with confirmation of first-line antiretroviral therapy (ART) failure were enrolled in this study from June 2006 to December 2016. Both the protease and reverse transcriptase genes were amplified and sequenced using Trugene® HIV-1 Genotyping Kit and OpenGene® DNA system at the biomolecular laboratory of the National Institute of Hygiene and Epidemiology, Vietnam. The Stanford HIV database algorithm was used for interpretation of resistance data and genotyping. Results: Drug resistance mutations were 90.7% in patients with first-line treatment failure. Amongst patients with drug resistance mutation, 97.7% resisted to non-nucleoside reverse transcriptase inhibitors (NNRTIs), followed by nucleoside reverse transcriptase inhibitors (NRTIs, 95.3%) and protease inhibitors (PIs, 11.6%). Amongst the genetic mutations resistant to NNRTIs, G190S mutation was the highest (51.2%), K101HQ mutation was 39.5% and Y181I mutation was 34.9%. In genetic mutations to NRTIs, M184V mutation was 88.4%. In thymidine analogue mutations, K70R mutation was the most common (37.2%), followed by D67N, T215F and T69N mutations (27.9%, 27.9% and 25.6%, respectively). In genetic mutations in PIs, M36I and K20R mutations made up 9.3%. In NNRTIs, the prevalence of nevirapine resistance was 55.8%, and that of efavirenz resistance was 4.7%. In NRTIs, the ratio of lamivudine resistance was 93.0%, and that of zidovudine resistance was 9.3%. No lopinavir/ritonavir resistance was recorded. Conclusions: Drug resistance mutations in patients with first-line ART failure had a high prevalence of NNRTI and NRTI resistance but still susceptible to PIs.