Antimicrobial resistance in southern China: results of prospective surveillance in Dongguan city, 2017

The Analysis of Drug-Resistant Bacteria from Different Regions of Anhui in 2021

Purpose

To analyze the differences in clinical distribution and antimicrobial resistance of pathogens among northern Anhui, central Anhui, and southern Anhui in 2021, and to provide a basis for the rational use of drugs for clinicians in different regions.

Methods

Nonrepetitive pathogens isolated from clinical samples of inpatients and outpatients from 59 member units with qualified data in 2021 were obtained from the Anhui Province Antimicrobial Resistance Surveillance System, which was divided into northern Anhui, central Anhui, and southern Anhui by region. Identification and antimicrobial susceptibility analyses were carried out using the Vitek 2 Compact and standard disc diffusion method. The results were determined according to the American Clinical Laboratory Standards Institute in 2021 with data analyzed using WHONET 5.6 and SPSS 17.0.

Results

A total of 133,268 pathogenic bacteria were isolated from clinical samples. Staphylococcus aureus (S. aureus) was the most common gram-positive bacterium and Escherichia coli (E. coli) was the most common gram-negative bacterium. Sputum was the main source of clinical specimens. The detection rates of methicillin-resistant S.aureus, methicillin-resistant coagulase-negative Staphylococcus, carbapenem-resistant E. coli, carbapenem-resistant Klebsiella pneumoniae (K. pneumoniae), carbapenem-resistant Acinetobacter baumannii, third-generation cephalosporin-resistant E. coli, and third-generation cephalosporin-resistant K. pneumoniae were higher in northern Anhui than in southern Anhui (P<0.0001). E. coli, K. pneumoniae, and Pseudomonas aeruginosa were sensitive to amikacin. Strains resistant to vancomycin, linezolid, and teicoplanin were not isolated until 2021.

Conclusion

There were significant differences in bacterial resistance in different regions of Anhui Province. Antibiotic resistance in northern Anhui was the most serious in 2021. Antimicrobial agents must be used according to the resistance of the bacteria in the local region.

Non-Canonical Host Intracellular Niche Links to New Antimicrobial Resistance Mechanism

Globally, infectious diseases are one of the leading causes of death among people of all ages. The development of antimicrobials to treat infectious diseases has been one of the most significant advances in medical history. Alarmingly, antimicrobial resistance is a widespread phenomenon that will, without intervention, make currently treatable infections once again deadly. In an era of widespread antimicrobial resistance, there is a constant and pressing need to develop new antibacterial drugs. Unraveling the underlying resistance mechanisms is critical to fight this crisis. In this review, we summarize some emerging evidence of the non-canonical intracellular life cycle of two priority antimicrobial-resistant bacterial pathogens: Pseudomonas aeruginosa and Staphylococcus aureus. The bacterial factors that modulate this unique intracellular niche and its implications in contributing to resistance are discussed. We then briefly discuss some recent research that focused on the promises of boosting host immunity as a combination therapy with antimicrobials to eradicate these two particular pathogens. Finally, we summarize the importance of various strategies, including surveillance and vaccines, in mitigating the impacts of antimicrobial resistance in general.

Mortality associated with third generation cephalosporin-resistance in Enterobacteriaceae infections: a multicenter cohort study in Southern China

Background: Emerging third-generation cephalosporin-resistant Enterobacteriaceae (3GCR-EB) pose global healthcare concern. This study assessed the in-hospital mortality attributed to 3GCR-EB.Methods: The study cohort comprised inpatients with community-onset or healthcare-associated infection caused by Enterobacteriaceae in three tertiary-care public hospitals in 2017. In-hospital mortality was compared between 3GCR-EB infected patients and third-generation cephalosporin-susceptible Enterobacteriaceae (3GCS-EB) infected patients using competing risk survival models.Results: Of 2,343 study patients (median age 60 years; 45.2% male), 1,481 (63.2%) had 3GCS-EB and 862 (36.8%) 3GCR-EB infection. 494 (57.0%) 3GCR-EB isolates were co-resistant to fluoroquinolones and 15 (1.7%) to carbapenems. In-hospital mortality was similar in 3GCS-EB and 3GCR-EB infections (2.4% vs. 2.8%; p = 0.601). No increase in the hazard of in-hospital mortality was detected for 3GCR-EB compared to 3GCS-EB infection (sub-distribution hazard ratio [HR] 0.80; 95%CI, 0.41-1.55) adjusting for patient age, sex, intensive care admission, origin of infection and site of infection. Analysis of cause-specific hazards showed that 3GCR-EB infections significantly decreased the daily rate of hospital discharge (cause-specific HR = 0.84; 95%CI, 0.76-0.92) leading to lengthier hospitalizations.Conclusion: 3GCR-EB infection per se was not associated with increased in-hospital mortality in this study, but placed significant healthcare burden by increasing the length of hospitalization.

Distribution and Antimicrobial Susceptibility of Gram-Positive and Gram-Negative Pathogens Isolated from Patients Hospitalized in a Tertiary Teaching Hospital in Southwestern China

Background: Bacteria are the most common causes of clinical infectious diseases. The distribution and antimicrobial resistance (AMR) rates of bacteria provide important guidelines for clinical antibacterial treatment; however, the information in this region is still missing. Objectives: This study aimed to evaluate the changes in the distribution and AMR rates of clinical isolates from inpatients. Methods: We conducted a retrospective cross-sectional analysis of the distribution and antimicrobial susceptibility of all non-duplicate Gram-negative bacterial (GNB) and Gram-positive bacterial (GPB) isolates collected from January 1, 2013, to December 31, 2018, in our hospital. Results: In total, 56,535 and 3,518 non-repetitive isolates were detected in the whole hospital and intensive care units (ICUs), respectively. The isolates included GPB (26.3% and 18.4%, respectively) and GNB (73.7% and 81.6%, respectively). The five dominant bacteria were the same in the whole hospital and ICUs, but Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii percentages were different. The detection rates of all isolates and five dominant bacteria were significantly different between the ICUs and the whole hospital (P < 0.05). The detection rate of extended-spectrum β-lactamase (ESBL)-E. coli (54.1%) was significantly higher than that of K. pneumoniae (26.1%). The detection rates of carbapenem-resistant (CR) and extensively drug-resistant (XDR)-A. baumannii were the highest in both the ICUs (87.1% and 21.8%, respectively) and the whole hospital (65.5% and 12.9%, respectively). The methicillin-resistant S. aureus (MRSA) detection rate was high (26.5%) but showed a significant decreasing trend (P < 0.05). The detection rates of ESBL and XDR-E. coli, CRAB, and XDR-S. aureus were significantly different between the ICUs and the whole hospital (P < 0.05). Gram-negative bacteria were highly susceptible to amikacin (> 90%) and tigecycline (> 98%). Staphylococcus aureus showed 100% susceptibility to vancomycin and linezolid. Acinetobacter baumannii had the highest resistance to imipenem (62.8%) and meropenem (64.0%). Except for A. baumannii and E. coli (P < 0.05), the AMR levels and the trends of the other isolates were similar between the ICUs and the whole hospital (P > 0.05). Conclusions: Currently, the appropriate antimicrobial agents in our hospital include amikacin and tigecycline for the treatment of GNB infections and vancomycin and linezolid for the treatment of GPB infections. Moreover, it is still necessary to monitor AMR in the ICUs and the whole hospital simultaneously.