Superinfection rate among the patients treated with carbapenem versus piperacillin/tazobactam: Retrospective observational study

Bacterial Superinfections in Critically Ill Patients With SARS-CoV-2 Infection: A Retrospective Cohort Study

Background: There is a considerable gap in the current evidence concerning the prevalence of superinfections among critically ill patients with SARS-CoV-2 infection in Saudi Arabia. Objectives: We sought to determine the prevalence of bacterial superinfections following the initiation of antibiotic therapy in critically ill patients with SARS-CoV-2 infection. Methods: A retrospective observational study that included patients with SARS-CoV-2 infection admitted to the intensive care unit (ICU) for at least 24 hours and received empirical antibiotic therapy. The primary outcome was the rate of bacterial superinfections occurring at least 48 hours after the initiation of antibiotics. ICU-related outcomes and complications were compared between subgroups with and without superinfections and amongst the two most frequently used antibiotic regimens. Results: A total of 230 patients were included in our study. Superinfections developed in 40 (17.4%) patients, with the median time from the first dose of antibiotic to the emergence of superinfection of 17.6 days (IQR 9.8-29.2). Patients with superinfections had longer median ICU stays [ 27.1 days(IQR 15.2-43.3) versus 7.1 days(IQR 3.8-11.8); P < 0.001], developed more complications [92.5% versus 52.6%; P < 0.001], and had higher ICU mortality [45.0% versus 22.1%; P = 0.0034] compared to patients without superinfections. The two most frequently prescribed antibiotic regimens were piperacillin/tazobactam plus levofloxacin (53.9%) and meropenem plus levofloxacin (19.7%). Although there was no significant difference in the rate of superinfections [15.3% versus 26.7%; P = 0.09] between the two groups, patients in the superinfections group who received piperacillin/tazobactam plus levofloxacin developed more complications [94.7% versus 91.7%; P < 0.001] and had a higher ICU mortality [57.9% versus 50%; P < 0.001]. Conclusion: Superinfections occurred at a higher rate in critically ill patients with SARS-CoV-2 infection post empirical antibiotics initiation. The use of piperacillin/tazobactam plus levofloxacin was associated with an increase in the rate of complications and higher ICU mortality. Larger multicenter studies are needed to confirm these results.

The quality of antimicrobial prescribing in skin and soft tissue management in Australian hospitals: an analysis of the National Antimicrobial Prescribing Survey data

BACKGROUND

Skin and soft tissue infections (SSTIs) are among the most common indications for antimicrobial prescribing in hospitals. Inappropriate antimicrobial use can lead to increased morbidity, unnecessary hospital re-admission and increased antimicrobial resistance. This study aimed to assess the quality of antimicrobial prescribing practices in SSTI management within Australian hospitals to provide guidance for future practice.

METHODS

A retrospective analysis was conducted with data from the National Antimicrobial Prescribing Survey (NAPS). SSTI prescribing data from Hospital NAPS (2013-2022) and surgical site infection data from Surgical NAPS (2016-2022) datasets were analysed. Variables assessed included guideline compliance, appropriateness as per the structured NAPS algorithm, and reasons for inappropriateness.

RESULTS

From the Hospital NAPS dataset, 40,535 antimicrobial prescriptions for SSTIs were analysed. The most common indication was cellulitis (34.1%, N=13,822), and the most prescribed antimicrobial was flucloxacillin (18.8%, N=7,638). SSTI indications had a lower rate of guideline compliance but a higher rate of appropriateness compared with all other indications for antimicrobial prescriptions (guideline compliance 66.3%, N=21,035 vs 67.4%, N=156,285; appropriateness 75.6%, N=30,639 vs 72.7%, N=209,383). The most common reason for inappropriateness was incorrect dose or frequency (29.3%, N=2367). From the Surgical NAPS dataset, 5674 prescriptions for surgical site infections were analysed. Of these, 68.2% (N=3867) were deemed to be appropriate. The most common reason for inappropriateness was incorrect dose or frequency (27.7%, N=350).

CONCLUSIONS

As SSTIs are a common indication for prescribing an antimicrobial in Australian hospitals, identifying effective antimicrobial stewardship strategies to optimize antimicrobial use for SSTI management is recommended to improve patient outcomes.

Flagellotropic Bacteriophages: Opportunities and Challenges for Antimicrobial Applications

Bacteriophages (phages) are the most abundant biological entities in the biosphere. As viruses that solely infect bacteria, phages have myriad healthcare and agricultural applications including phage therapy and antibacterial treatments in the foodservice industry. Phage therapy has been explored since the turn of the twentieth century but was no longer prioritized following the invention of antibiotics. As we approach a post-antibiotic society, phage therapy research has experienced a significant resurgence for the use of phages against antibiotic-resistant bacteria, a growing concern in modern medicine. Phages are extraordinarily diverse, as are their host receptor targets. Flagellotropic (flagellum-dependent) phages begin their infection cycle by attaching to the flagellum of their motile host, although the later stages of the infection process of most of these phages remain elusive. Flagella are helical appendages required for swimming and swarming motility and are also of great importance for virulence in many pathogenic bacteria of clinical relevance. Not only is bacterial motility itself frequently important for virulence, as it allows pathogenic bacteria to move toward their host and find nutrients more effectively, but flagella can also serve additional functions including mediating bacterial adhesion to surfaces. Flagella are also a potent antigen recognized by the human immune system. Phages utilizing the flagellum for infections are of particular interest due to the unique evolutionary tradeoff they force upon their hosts: by downregulating or abolishing motility to escape infection by a flagellotropic phage, a pathogenic bacterium would also likely attenuate its virulence. This factor may lead to flagellotropic phages becoming especially potent antibacterial agents. This review outlines past, present, and future research of flagellotropic phages, including their molecular mechanisms of infection and potential future applications.