Does adjunctive clindamycin have a role in Staphylococcus aureus bacteremia? A protocol for the adjunctive treatment domain of the S. aureus Network Adaptive Platform (SNAP) randomized controlled trial.

INTRODUCTION: The use of adjunctive antibiotics directed against exotoxin production in Staphylococcus aureus bacteremia (SAB) is widespread, and is recommended in many guidelines, but there is limited evidence underpinning this. Existing guidelines are based on the theoretical premise of toxin suppression, as many strains of S. aureus produce toxins such as leucocidins (e.g., Panton-Valentine Leucocidin (PVL), toxic shock syndrome toxin 1 (TSST-1), exfoliative toxins, and various enterotoxins). Many clinicians therefore believe that limiting exotoxin production release by S. aureus could reduce its virulence and improve clinical outcomes. Clindamycin, a protein synthesis inhibitor antibiotic, is commonly used for this purpose. We report the domain-specific protocol, embedded in a large adaptive, platform trial, seeking to definitively answer this question. METHODS AND ANALYSIS: The Staphylococcus aureus Network Adaptive Platform (SNAP) trial is a pragmatic, randomized, multi-center adaptive platform trial that aims to compare different SAB therapies, simultaneously, for 90-day mortality. The adjunctive treatment domain aims to test the effectiveness of adjunctive antibiotics, initially comparing clindamycin to no adjunctive antibiotic, but future adaptations may include other agents. Individuals will be randomized to receive either five days of adjunctive clindamycin (or lincomycin) or no adjunctive antibiotic therapy alongside standard of care antibiotics. Most participants with SAB (within 72hr of index blood culture and not contraindicated) will be eligible to participate in this domain. Prespecified analyses are defined in the statistical appendix to the core protocol and domain-specific secondary analyses will be adjusted for resistance to clindamycin, disease phenotype (complicated or uncomplicated SAB) and PVL-positive isolate.

Genomic investigation and clinical correlates of the in vitro ß-lactam: NaHCO3 responsiveness phenotype among methicillin-resistant Staphylococcus aureus isolates from a randomized clinical trial.

NaHCO3 responsiveness is a novel phenotype where some methicillin-resistant Staphylococcus aureus (MRSA) isolates exhibit significantly lower minimal inhibitory concentrations (MIC) to oxacillin and/or cefazolin in the presence of NaHCO3. NaHCO3 responsiveness correlated with treatment response to ß-lactams in an endocarditis animal model. We investigated whether treatment of NaHCO3-responsive strains with ß-lactams was associated with faster clearance of bacteremia. The CAMERA2 trial (Combination Antibiotics for Methicillin-Resistant Staphylococcus aureus) randomly assigned participants with MRSA bloodstream infections to standard therapy, or to standard therapy plus an anti-staphylococcal ß-lactam (combination therapy). For 117 CAMERA2 MRSA isolates, we determined by broth microdilution the MIC of cefazolin and oxacillin, with and without 44 mM of NaHCO3. Isolates exhibiting ≥4-fold decrease in the MIC to cefazolin or oxacillin in the presence of NaHCO3 were considered "NaHCO3-responsive" to that agent. We compared the rate of persistent bacteremia among participants who had infections caused by NaHCO3-responsive and non-responsive strains, and that were assigned to combination treatment with a ß-lactam. Thirty-one percent (36/117) and 25% (21/85) of MRSA isolates were NaHCO3-responsive to cefazolin and oxacillin, respectively. The NaHCO3-responsive phenotype was significantly associated with sequence type 93, SCCmec type IVa, and mecA alleles with substitutions in positions -7 and -38 in the regulatory region. Among participants treated with a ß-lactam, there was no association between the NaHCO3-responsive phenotype and persistent bacteremia (cefazolin, P = 0.82; oxacillin, P = 0.81). In patients from a randomized clinical trial with MRSA bloodstream infection, isolates with an in vitro ß-lactam-NaHCO3-responsive phenotype were associated with distinctive genetic signatures, but not with a shorter duration of bacteremia among those treated with a ß-lactam.

Hepatitis B genotypes in Aboriginal and Torres Strait Islander Australians: correlation with clinical course and implications for management.

BACKGROUND: The prevalence of chronic hepatitis B (CHB) in Aboriginal and Torres Strait Islander Australians in Far North Queensland (FNQ) is greater than twice that of the general Australian population. CHB is common in Torres Strait Islanders diagnosed with hepatocellular carcinoma (HCC) - and in Aboriginals with HCC living in the Northern Territory - however, Aboriginals diagnosed with HCC in FNQ very rarely have CHB. The explanation for this apparent disparity is uncertain. AIMS: To determine the HBV genotypes in the FNQ Aboriginal and Torres Strait Islander population and their correlation with clinical phenotype. METHODS: We determined the HBV genotype of Aboriginal and Torres Strait Islander Australians living with CHB in FNQ and correlated this with demographic and clinical findings. RESULTS: 134/197 (68%) enrolled individuals had a sufficient viral load for genotyping. All 40 people with HBV/D genotype had Aboriginal heritage, whereas 85/93 (91%) with HBV/C had Torres Strait Islander heritage (P < 0.0001). Individuals with HBV/D were younger than those with HBV/C (median (interquartile range) age: 43 (39-48) vs 53 (42-66) years, P = 0.0002). However, they were less likely to be HBeAg positive (1/40 (3%) vs 23/93 (25%), P = 0.001). All three HCCs developed in Torres Strait Islanders; two-thirds were infected with HBV/C14; genotyping was not possible in the other individual. All 10 diagnoses of cirrhosis occurred in Torres Strait Islanders, 6/10 were infected with HBV/C14, genotyping was not possible in the other four individuals. CONCLUSIONS: HBV genotypes in Aboriginal and Torres Strait Islander Australians in FNQ differ markedly, which could explain the significant differences in the clinical phenotype in the two populations and might be used to inform cost-effective CHB care in the region.

Avoiding misclassification of acute kidney injury: Timing is everything.

Accurate detection of acute kidney injury (AKI) in clinical trials is important. Using a 'baseline' creatinine from trial enrolment may not be ideal for understanding a participant's true baseline kidney function. We aimed to determine if a 'pre-trial baseline creatinine' resulted in comparable creatinine concentrations to a 'trial baseline creatinine', and how the timing of baseline creatinine affected the incidence of AKI in the Combination Antibiotic therapy for MEthicillin Resistant Staphylococcus aureus (CAMERA2) randomised trial. Study sites retrospectively collected a pre-trial baseline creatinine from up to 1 year before CAMERA2 trial enrolment ideally when the patient was medically stable. Baseline creatinine from CAMERA2 (the 'trial baseline creatinine'), was the highest creatinine measurement in the 24 h preceding trial randomisation. We used Wilcoxon sign rank test to compare pre-trial and trial baseline creatinine concentrations. We included 217 patients. The median pre-trial baseline creatinine was significantly lower than the median trial baseline creatinine (82 µmol/L [IQR 65-104 µmol/L] versus 86 µmol/L [IQR 66-152 µmol/L] p = <0.001). Using pre-trial baseline creatinine, 48 of 217 patients (22%) met criteria for an AKI at CAMERA2 enrolment and only 5 of these patients met criteria for an AKI using the CAMERA2 study protocol (using baseline creatinine from trial entry). Using a baseline creatinine from the time of trial enrolment failed to detect many patients with AKI. Trial protocols should consider the optimal timing of baseline creatinine and the limitations of using a baseline creatinine during an acute illness.

An evaluation and refinement of the "Hep B Story" app, tailored to meet the community's cultural needs.

BACKGROUND: Hepatitis B is endemic amongst the Australian Aboriginal population in the Northern Territory. A participatory action research project identified the lack of culturally appropriate education tools and led to the development of the "Hep B Story" app in the Aboriginal language Yolŋu Matha. This paper describes a formal evaluation of the app's first version, which informed improvements and translation into a further ten Aboriginal languages. METHODS: The evaluation employed Participatory Action Research (PAR) principles to work within Indigenous research methodologies and prioritise Indigenous knowledge to improve the app iteratively. Semi-structured interviews and focus groups were conducted across the Northern Territory with 11 different language groups. Local Community Based Researchers and Aboriginal Research team members coordinated sessions. The recorded, translated conversations were transcribed verbatim and thematically analysed using an inductive and deductive approach. RESULTS: Between November 2018 and September 2020, 94 individuals from 11 language groups participated in 25 semi-structured interviews and 10 focus groups. All participants identified as Aboriginal. Most participants felt the app would be culturally appropriate for Aboriginal communities in the Northern Territory and improve knowledge surrounding hepatitis B. The information gathered from these interviews allowed for identifying five main themes: support for app, relationships, concept versus language, shame, and perceptions of images, along with errors that required modification. CONCLUSIONS: A "real-life" evaluation of the app was comprehensively completed using a PAR approach blended with Indigenous research methods. This evaluation allowed us to develop an updated and enhanced version of the app before creating the additional ten language versions. An iterative approach alongside strong community engagement was pivotal in ensuring the app's cultural safety and appropriateness. We recommend avoiding the use of knowledge-based evaluations in an Aboriginal setting to ensure relevant and culturally appropriate feedback is obtained.

External Validation of the Joint-Specific Bone Involvement, Antimicrobial Options, Coverage of the Soft Tissues, and Host Status (JS-BACH) Classification for Predicting Outcome in Periprosthetic Joint Infections: A Cohort of 653 Patients.

BACKGROUND: Periprosthetic joint infection (PJI) is a devastating complication in hip and knee joint arthroplasty. The "Joint-Specific Bone Involvement, Antimicrobial Options, Coverage of the Soft Tissues, and Host Status (JS-BACH)" classification system was developed in 2021 to stratify the complexity of PJI, and more importantly, to act as a tool to guide referrals to specialist centers. The "JS-BACH" classification has not been validated in an external cohort. This study aimed to do so using a large prospective cohort from Australia and New Zealand. METHODS: We applied the JS-BACH classification to the Prosthetic Joint Infection in Australia and New Zealand Observational (PIANO) cohort. This prospective study of newly diagnosed PJI collected 2-year outcome data from 653 participants enrolled in 27 hospitals. The definition of PJI treatment failure at 24 months was any of the following: death, clinical or microbiological signs of infection, destination prosthesis removed, or ongoing antibiotic use. Individual cases were classified as per JS-BACH into "1: uncomplicated" (n = 268), "2: complex" (n = 330), and "3: limited options" (n = 55). This cohort was similar to the original JS-BACH population in terms of baseline characteristics. However, there was a difference in complexity, with more debridement, antibiotics, and implant retention procedures, fewer revision procedures, and a higher proportion of uncomplicated patients in the PIANO cohort. RESULTS: The risk of treatment failure correlated strongly with the JS-BACH category, with odds ratios (95% confidence interval) for category 2 versus 1 of 1.75 (1.24 to 2.47) and for category 3 versus 1 of 7.12 (3.42 to 16.02). CONCLUSIONS: Despite the PIANO study population being less complicated than the original derivation cohort, the JS-BACH classification showed a clear association with treatment failure in this large external cohort.

Continuous vs Intermittent ß-Lactam Antibiotic Infusions in Critically Ill Patients With Sepsis: The BLING III Randomized Clinical Trial.

Importance: Whether ß-lactam antibiotics administered by continuous compared with intermittent infusion reduces the risk of death in patients with sepsis is uncertain. Objective: To evaluate whether continuous vs intermittent infusion of a ß-lactam antibiotic (piperacillin-tazobactam or meropenem) results in decreased all-cause mortality at 90 days in critically ill patients with sepsis. Design, Setting, and Participants: An international, open-label, randomized clinical trial conducted in 104 intensive care units (ICUs) in Australia, Belgium, France, Malaysia, New Zealand, Sweden, and the United Kingdom. Recruitment occurred from March 26, 2018, to January 11, 2023, with follow-up completed on April 12, 2023. Participants were critically ill adults (≥18 years) treated with piperacillin-tazobactam or meropenem for sepsis. Intervention: Eligible patients were randomized to receive an equivalent 24-hour dose of a ß-lactam antibiotic by either continuous (n = 3498) or intermittent (n = 3533) infusion for a clinician-determined duration of treatment or until ICU discharge, whichever occurred first. Main Outcomes and Measures: The primary outcome was all-cause mortality within 90 days after randomization. Secondary outcomes were clinical cure up to 14 days after randomization; new acquisition, colonization, or infection with a multiresistant organism or Clostridioides difficile infection up to 14 days after randomization; ICU mortality; and in-hospital mortality. Results: Among 7202 randomized participants, 7031 (mean [SD] age, 59 [16] years; 2423 women [35%]) met consent requirements for inclusion in the primary analysis (97.6%). Within 90 days, 864 of 3474 patients (24.9%) assigned to receive continuous infusion had died compared with 939 of 3507 (26.8%) assigned intermittent infusion (absolute difference, -1.9% [95% CI, -4.9% to 1.1%]; odds ratio, 0.91 [95% CI, 0.81 to 1.01]; P = .08). Clinical cure was higher in the continuous vs intermittent infusion group (1930/3467 [55.7%] and 1744/3491 [50.0%], respectively; absolute difference, 5.7% [95% CI, 2.4% to 9.1%]). Other secondary outcomes were not statistically different. Conclusions and Relevance: The observed difference in 90-day mortality between continuous vs intermittent infusions of ß-lactam antibiotics did not meet statistical significance in the primary analysis. However, the confidence interval around the effect estimate includes the possibility of both no important effect and a clinically important benefit in the use of continuous infusions in this group of patients. Trial Registration: ClinicalTrials.gov Identifier: NCT03213990.

Adapting and translating the 'Hep B Story' App the right way: A transferable toolkit to develop health resources with, and for, Aboriginal people.

ISSUE ADDRESSED: In 2014 the 'Hep B Story App', the first hepatitis B educational app in an Aboriginal language was released. Subsequently, in 2018, it was assessed and adapted before translation into an additional 10 Aboriginal languages. The translation process developed iteratively into a model that may be applied when creating any health resource in Aboriginal languages. METHODS: The adaptation and translation of the 'Hep B Story' followed a tailored participatory action research (PAR) process involving crucial steps such as extensive community consultation, adaptation of the original material, forward and back translation of the script, content accuracy verification, voiceover recording, and thorough review before the publication of the new version. RESULTS: Iterative PAR cycles shaped the translation process, leading to a refined model applicable to creating health resources in any Aboriginal language. The community-wide consultation yielded widespread chronic hepatitis B education, prompting participants to share the story within their families, advocating for hepatitis B check-ups. The project offered numerous insights and lessons, such as the significance of allocating sufficient time and resources to undertake the process. Additionally, it highlighted the importance of implementing flexible work arrangements and eliminating barriers to work for the translators. CONCLUSIONS: Through our extensive work across the Northern Territory, we produced an educational tool for Aboriginal people in their preferred languages and developed a translation model to create resources for different cultural and linguistic groups. SO WHAT?: This translation model provides a rigorous, transferable method for creating accurate health resources for culturally and linguistically diverse populations.

Early oral antibiotic switch in Staphylococcus aureus bacteraemia: The Staphylococcus aureus Network Adaptive Platform (SNAP) Trial Early Oral Switch Protocol.

BACKGROUND: Staphylococcus aureus bloodstream infection (bacteraemia) is traditionally treated with at least two weeks of IV antibiotics in adults, 3-7 days in children, and often longer for those with complicated disease. The current practice of treating S. aureus bacteraemia (SAB) with prolonged IV antibiotics (rather than oral antibiotics) is based on historical observational research and expert opinion. Prolonged IV antibiotic therapy has significant disadvantages for patients and healthcare systems, and there is growing interest in whether a switch to oral antibiotics following an initial period of IV therapy is a safe alternative for clinically stable patients. PROTOCOL: The early oral switch (EOS) domain of the S. aureus Network Adaptive Platform (SNAP) trial will assess early switch to oral antibiotics compared with continued IV treatment in clinically stable patients with SAB. The primary endpoint is 90-day all-cause mortality. Hospitalised SAB patients are assessed at platform day 7 +/- 2 (uncomplicated SAB) and day 14 +/-2 (complicated SAB) to determine their eligibility for randomisation to EOS (intervention) or continued IV treatment (current standard of care). DISCUSSION: Recruitment is occurring to the EOS domain of the SNAP trial. As of August 2023, 21% of all SNAP participants had been randomised to the EOS domain, a total of 264 participants across 77 centres, with an aim to recruit at least 1000 participants. We describe challenges and facilitators to enrolment in this domain to aid those planning similar trials.

Current Epidemiology and Clinical Features of Cryptococcus Infection in Patients Without Human Immunodeficiency Virus: A Multicenter Study in 46 Hospitals in Australia and New Zealand.

BACKGROUND: Patients without human immunodeficiency virus (HIV) are increasingly recognized as being at risk for cryptococcosis. Knowledge of characteristics of cryptococcosis in these patients remains incomplete. METHODS: We conducted a retrospective study of cryptococcosis in 46 Australian and New Zealand hospitals to compare its frequency in patients with and without HIV and describe its characteristics in patients without HIV. Patients with cryptococcosis between January 2015 and December 2019 were included. RESULTS: Of 475 patients with cryptococcosis, 90% were without HIV (426 of 475) with marked predominance in both Cryptococcus neoformans (88.7%) and Cryptococcus gattii cases (94.3%). Most patients without HIV (60.8%) had a known immunocompromising condition: cancer (n = 91), organ transplantation (n = 81), or other immunocompromising condition (n = 97). Cryptococcosis presented as incidental imaging findings in 16.4% of patients (70 of 426). The serum cryptococcal antigen test was positive in 85.1% of tested patients (319 of 375); high titers independently predicted risk of central nervous system involvement. Lumbar puncture was performed in 167 patients to screen for asymptomatic meningitis, with a positivity rate of 13.2% where meningitis could have been predicted by a high serum cryptococcal antigen titer and/or fungemia in 95% of evaluable cases. One-year all-cause mortality was 20.9% in patients without HIV and 21.7% in patients with HIV (P = .89). CONCLUSIONS: Ninety percent of cryptococcosis cases occurred in patients without HIV (89% and 94% for C. neoformans and C. gattii, respectively). Emerging patient risk groups were evident. A high level of awareness is warranted to diagnose cryptococcosis in patients without HIV.

A multi-site, international laboratory study to assess the performance of penicillin susceptibility testing of Staphylococcus aureus.

OBJECTIVES: There is clinical uncertainty over the optimal treatment for penicillin-susceptible Staphylococcus aureus (PSSA) infections. Furthermore, there is concern that phenotypic penicillin susceptibility testing methods are not reliably able to detect some blaZ-positive S. aureus. METHODS: Nine S. aureus isolates, including six genetically diverse strains harbouring blaZ, were sent in triplicate to 34 participating laboratories from Australia (n = 14), New Zealand (n = 6), Canada (n = 12), Singapore (n = 1) and Israel (n = 1). We used blaZ PCR as the gold standard to assess susceptibility testing performance of CLSI (P10 disc) and EUCAST (P1 disc) methods. Very major errors (VMEs), major error (MEs) and categorical agreement were calculated. RESULTS: Twenty-two laboratories reported 593 results according to CLSI methodology (P10 disc). Nineteen laboratories reported 513 results according to the EUCAST (P1 disc) method. For CLSI laboratories, the categorical agreement and calculated VME and ME rates were 85% (508/593), 21% (84/396) and 1.5% (3/198), respectively. For EUCAST laboratories, the categorical agreement and calculated VME and ME rates were 93% (475/513), 11% (84/396) and 1% (3/198), respectively. Seven laboratories reported results for both methods, with VME rates of 24% for CLSI and 12% for EUCAST. CONCLUSIONS: The EUCAST method with a P1 disc resulted in a lower VME rate compared with the CLSI methods with a P10 disc. These results should be considered in the context that among collections of PSSA isolates, as determined by automated MIC testing, less than 10% harbour blaZ. Furthermore, the clinical relevance of phenotypically susceptible, but blaZ-positive S. aureus, remains unclear.

Optimal drug therapy for Staphylococcus aureus bacteraemia in adults.

PURPOSE OF REVIEW: Staphylococcus aureus is a significant human pathogen, causing a variety of infections, from skin and soft tissue infections to endocarditis, bone and joint infections and deep tissue abscesses. Mortality from S. aureus bacteraemia remains high, without major therapeutic advances in recent decades. RECENT FINDINGS: In recent years, optimized dosing of antibiotics is increasingly being recognized as a cornerstone of management for severe infections including S. aureus bacteraemia. This comprehensive review details the pharmacokinetics/pharmacodynamics (PK/PD) targets for commonly used antistaphylococcal antibiotics and the doses predicted to achieve them in clinical practice. Recent advances in dosing of teicoplanin and use of cefazolin in CNS infections and findings from combination therapy studies are discussed. Drug exposure relationships related to toxicity are also detailed. SUMMARY: This review details the different PK/PD targets for drugs used to treat S. aureus bacteraemia and how to apply them in various scenarios. The drug doses that achieve them, and the risks of toxicity are also provided.

Temporal patterns of antibiotic prescribing for sore throat, otitis media, and sinusitis: a longitudinal study of general practitioner registrars.

BACKGROUND: Antibiotics provide minimal benefit for sore throat, otitis media, and sinusitis. Antibiotic stewardship, with reduced prescribing, is required to address antibiotic resistance. As most antibiotic prescribing occurs in general practice and prescribing habits develop early, general practitioner (GP) trainees (registrars) are important for effective antibiotic stewardship. OBJECTIVES: To establish temporal trends in Australian registrars' antibiotic prescribing for acute sore throat, acute otitis media, and acute sinusitis. DESIGN: A longitudinal analysis of data from the Registrar Clinical Encounters in Training (ReCEnT) study from 2010 to 2019. PARTICIPANTS: ReCEnT is an ongoing cohort study of registrars' in-consultation experiences and clinical behaviours. Pre-2016, 5 of 17 Australian training regions participated. From 2016, 3 of 9 regions (42% of Australian registrars) participate. MAIN MEASURES: The outcome was prescription of an antibiotic for a new acute problem/diagnosis of sore throat, otitis media, or sinusitis. The study factor was year (2010-2019). KEY RESULTS: Antibiotics were prescribed in 66% of sore throat diagnoses, 81% of otitis media, and in 72% of sinusitis. Prescribing frequencies decreased between 2010 and 2019 by 16% for sore throat (from 76% to 60%) by 11% for otitis media (from 88% to 77%) and by 18% for sinusitis (from 84% to 66%). In multivariable analyses, "Year" was associated with reduced prescribing for sore throat (OR 0.89; 95%CI 0.86-0.92; p < 0.001), otitis media (OR 0.90; 95%CI 0.86-0.94; p < 0.001), and sinusitis (OR 0.90; 95%CI 0.86, 0.94; p < 0.001). CONCLUSIONS: Registrars' prescribing rates for sore throat, otitis media, and sinusitis significantly decreased during the period 2010-2019. However, educational (and other) interventions to further reduce prescribing are warranted.

"The most culturally safe training I've ever had": the co-design of a culturally safe Managing hepatitis B training course with and for the Aboriginal health workforce of the Northern Territory of Australia.

BACKGROUND: The Aboriginal health workforce provide responsive, culturally safe health care. We aimed to co-design a culturally safe course with and for the Aboriginal health workforce. We describe the factors which led to the successful co-design, delivery, and evaluation of the "Managing hepatitis B" course for the Aboriginal health workforce. METHODS: A Participatory Action Research approach was used, involving ongoing consultation to iteratively co-design and then develop course content, materials, and evaluation tools. An Aboriginal and Torres Strait Islander research and teaching team received education in chronic hepatitis B and teaching methodologies. Pilot courses were held, in remote communities of the Northern Territory, using two-way learning and teach-back methods to further develop the course and assess acceptability and learnings. Data collection involved focus group discussions, in-class observations, reflective analysis, and use of co-designed and assessed evaluation tools. RESULTS: Twenty-six participants attended the pilot courses. Aboriginal and Torres Strait Islander facilitators delivered a high proportion of the course. Evaluations demonstrated high course acceptability, cultural safety, and learnings. Key elements contributing to success and acceptability were acknowledging, respecting, and integrating cultural differences into education, delivering messaging and key concepts through an Aboriginal and Torres Strait Islander lens, using culturally appropriate approaches to learning including storytelling and visual teaching methodologies. Evaluation of culturally safe frameworks and findings from the co-design process led to the creation of a conceptual framework, underpinned by meeting people's basic needs, and offering a safe and comfortable environment to enable productive learning with attention to the following: sustenance, financial security, cultural obligations, and gender and kinship relationships. CONCLUSIONS: Co-designed education for the Aboriginal health workforce must embed principles of cultural safety and meaningful community consultation to enable an increase in knowledge and empowerment. The findings of this research can be used to guide the design of future health education for First Nations health professionals and to other non-dominant cultures. The course model has been successfully transferred to other health issues in the Northern Territory.

Success of Debridement, Antibiotics, and Implant Retention in Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: Results From a Prospective Multicenter Study of 189 Cases.

BACKGROUND: This study aimed to identify the success rate of debridement, antibiotics, and implant retention (DAIR) for prosthetic joint infection (PJI) in a large prospective cohort of patients undergoing total knee arthroplasty (TKA). The ability for different PJI classification systems to predict success was assessed. METHODS: Prospective data recorded in the Prosthetic Joint Infection in Australia and New Zealand Observational study were analyzed. One hundred eighty-nine newly diagnosed knee PJIs were managed with DAIR between July 2014 and December 2017. Patients were prospectively followed up for 2 years. A strict definition of success was used, requiring the patient being alive with documented absence of infection, no ongoing antibiotics and the index prosthesis in place. Success was compared against the Coventry (early PJI ≤1 month), International Consensus Meeting (early ≤90 days), Auckland (early <1 year), and Tsukayama (early ≤1 month, hematogenous >1 month with <7 days symptoms, chronic >1 month with >7 days symptoms) classifications. RESULTS: DAIR success was 45% (85/189) and was highest in early PJIs defined according to the Coventry (adjusted odds ratio [aOR] = 3.9, P = .01), the International Consensus Meeting (aOR = 3.1, P = .01), and the Auckland classifications (aOR = 2.6, P = .01). Success was lower in both hematogenous (aOR = 0.4, P = .03) and chronic infections (aOR = 0.1, P = .003). CONCLUSION: Time since primary TKA is an important predictor of DAIR success. Success was highest in infections occurring <1 month of the primary TKA and progressively decreased as time since the primary TKA increased.

The Staphylococcus aureus Network Adaptive Platform Trial Protocol: New Tools for an Old Foe.

Staphylococcus aureus bloodstream (SAB) infection is a common and severe infectious disease, with a 90-day mortality of 15%-30%. Despite this, <3000 people have been randomized into clinical trials of treatments for SAB infection. The limited evidence base partly results from clinical trials for SAB infections being difficult to complete at scale using traditional clinical trial methods. Here we provide the rationale and framework for an adaptive platform trial applied to SAB infections. We detail the design features of the Staphylococcus aureus Network Adaptive Platform (SNAP) trial that will enable multiple questions to be answered as efficiently as possible. The SNAP trial commenced enrolling patients across multiple countries in 2022 with an estimated target sample size of 7000 participants. This approach may serve as an exemplar to increase efficiency of clinical trials for other infectious disease syndromes.

Preventing early childhood transmission of hepatitis B in remote aboriginal communities in Northern Australia.

BACKGROUND: Chronic hepatitis B is a public health concern in Aboriginal communities in the Northern Territory of Australia with prevalence almost four times the non-Aboriginal population. Infection is suspected to mainly occur in early life, however, the mode of transmission and vaccine effectiveness is not known in this population. WHO has set a target for hepatitis B elimination by 2030; elimination in this disproportionately affected population in Australia will require understanding of the modes of transmission and vaccine effectiveness. METHODS: We conducted the study at four very remote Aboriginal communities. We approached mothers who had chronic hepatitis B and had given birth between 1988 and 2013 for consent. We obtained hepatitis B serology, immunisation and birth details from the medical record. If both mother and child had hepatitis B viral DNA detected, we performed viral whole genome sequencing. RESULTS: We approached 45 women for consent, of whom 23 agreed to participate. We included 20 mothers and 38 of their children. Of the 20 included mothers, 5 (25%) had children who were hepatitis B immune by exposure and 3 (15%) had children with evidence of chronic hepatitis B infection at the time of assessment. Hepatitis B immunoglobulin (HBIg) had been given at birth in 29/38 (76.3, 95% CI 59.8-88.6) children, and 26 children (68.4, 95% CI 51.3-82.5) were fully vaccinated. Of the 3 children who had chronic hepatitis B, all had received HBIg at birth and two were fully vaccinated. Of the 5 who were immune by exposure, 4 had received HBIg at birth and one was fully vaccinated. Whole genome sequencing revealed one episode of definite mother to child transmission. There was also one definite case of horizontal transmission. CONCLUSIONS: Chronic hepatitis B in this context is a sensitive issue, with a high proportion of women refusing consent. Although uncommon, there is ongoing transmission of hepatitis B to Aboriginal children in remote northern Australia despite vaccination, and this is likely occurring by both vertical and horizontal routes. Prevention will require ongoing investment to overcome the many barriers experienced by this population in accessing care.

Antibiotic prescribing for upper respiratory tract infections and acute bronchitis: a longitudinal analysis of general practitioner trainees.

BACKGROUND: Most antibiotic prescribing for upper respiratory tract infections (URTIs) and acute bronchitis is inappropriate. Substantive and sustained reductions in prescribing are needed to reduce antibiotic resistance. Prescribing habits develop early in clinicians' careers. Hence, general practice (GP) trainees are an important group to target. OBJECTIVES: We aimed to establish temporal trends in antibiotic prescribing for URTIs and acute bronchitis/bronchiolitis by Australian GP trainees (registrars). METHODS: A longitudinal analysis, 2010-2019, of the Registrars Clinical Encounters in Training (ReCEnT) dataset. In ReCEnT, registrars record clinical and educational content of 60 consecutive consultations, on 3 occasions, 6 monthly. Analyses were of new diagnoses of URTI and acute bronchitis/bronchiolitis, with the outcome variable a systemic antibiotic being prescribed. The independent variable of interest was year of prescribing (modelled as a continuous variable). RESULTS: 28,372 diagnoses of URTI and 5,289 diagnoses of acute bronchitis/bronchiolitis were recorded by 2,839 registrars. Antibiotic prescribing for URTI decreased from 24% in 2010 to 12% in 2019. Prescribing for acute bronchitis/bronchiolitis decreased from 84% to 72%. "Year" was significantly, negatively associated with antibiotic prescribing for both URTI (odds ratio [OR] 0.90; 95% confidence interval [CI]: 0.88-0.93) and acute bronchitis/bronchiolitis (OR 0.92; 95% CI: 0.88-0.96) on multivariable analysis, with estimates representing the mean annual change. CONCLUSIONS: GP registrars' prescribing for URTI and acute bronchitis/bronchiolitis declined over the 10-year period. Prescribing for acute bronchitis/bronchiolitis, however, remains higher than recommended benchmarks. Continued education and programme-level antibiotic stewardship interventions are required to further reduce registrars' antibiotic prescribing for acute bronchitis/bronchiolitis to appropriate levels.

It is well known that antibiotic consumption can cause antibiotic resistance. Most antibiotic prescribing happens in general practice. The common cold (upper respiratory tract infections) and cough (acute bronchitis) are 2 conditions that antibiotics are often prescribed for, but are not needed. There is considerable evidence that antibiotics do not help these conditions improve, and guidelines in Australia state that they are not a treatment option. General practitioners at the beginning of their career form prescribing habits early on. In light of the problem of antibiotic resistance, it is important to know how new doctors prescribe antibiotics, as they may do this for the rest of their career. We investigated their prescribing for the common cold and cough, from 2010 to 2019. We found that overall their prescribing has been declining over the last 10 years, but prescribing for cough is still too high. There needs to be more interventions in this group of doctors to reduce prescribing for this condition.

Proposed empiric antibiotic therapy for prosthetic joint infections: an analysis of the Prosthetic Joint Infection in Australia and New Zealand, Observational (PIANO) cohort.

Empiric antibiotic therapy in suspected prosthetic joint infection should cover likely pathogens while avoiding overly broad-spectrum antibiotics. We analysed individual patient data from a large prospective cohort study (Prosthetic Joint Infection in Australia and New Zealand, Observational (PIANO)) and found that causative organisms vary with the presentation type, with early post-operative infections more likely to be polymicrobial (41%) compared with late acute infections (10%). We thus propose empirical regimens tailored to the presentation type and presence or absence of sepsis.