High-risk Escherichia coli clones that cause neonatal meningitis and association with recrudescent infection.

Neonatal meningitis is a devastating disease associated with high mortality and neurological sequelae. Escherichia coli is the second most common cause of neonatal meningitis in full-term infants (herein NMEC) and the most common cause of meningitis in preterm neonates. Here, we investigated the genomic relatedness of a collection of 58 NMEC isolates spanning 1974-2020 and isolated from seven different geographic regions. We show NMEC are comprised of diverse sequence types (STs), with ST95 (34.5%) and ST1193 (15.5%) the most common. No single virulence gene profile was conserved in all isolates; however, genes encoding fimbrial adhesins, iron acquisition systems, the K1 capsule, and O antigen types O18, O75, and O2 were most prevalent. Antibiotic resistance genes occurred infrequently in our collection. We also monitored the infection dynamics in three patients that suffered recrudescent invasive infection caused by the original infecting isolate despite appropriate antibiotic treatment based on antibiogram profile and resistance genotype. These patients exhibited severe gut dysbiosis. In one patient, the causative NMEC isolate was also detected in the fecal flora at the time of the second infection episode and after treatment. Thus, although antibiotics are the standard of care for NMEC treatment, our data suggest that failure to eliminate the causative NMEC that resides intestinally can lead to the existence of a refractory reservoir that may seed recrudescent infection.

Host gene expression signatures to identify infection type and organ dysfunction in children evaluated for sepsis: a multicentre cohort study.

BACKGROUND: Sepsis is defined as dysregulated host response to infection that leads to life-threatening organ dysfunction. Biomarkers characterising the dysregulated host response in sepsis are lacking. We aimed to develop host gene expression signatures to predict organ dysfunction in children with bacterial or viral infection. METHODS: This cohort study was done in emergency departments and intensive care units of four hospitals in Queensland, Australia, and recruited children aged 1 month to 17 years who, upon admission, underwent a diagnostic test, including blood cultures, for suspected sepsis. Whole-blood RNA sequencing of blood was performed with Illumina NovaSeq (San Diego, CA, USA). Samples with completed phenotyping, monitoring, and RNA extraction by March 31, 2020, were included in the discovery cohort; samples collected or completed thereafter and by Oct 27, 2021, constituted the Rapid Paediatric Infection Diagnosis in Sepsis (RAPIDS) internal validation cohort. An external validation cohort was assembled from RNA sequencing gene expression count data from the observational European Childhood Life-threatening Infectious Disease Study (EUCLIDS), which recruited children with severe infection in nine European countries between 2012 and 2016. Feature selection approaches were applied to derive novel gene signatures for disease class (bacterial vs viral infection) and disease severity (presence vs absence of organ dysfunction 24 h post-sampling). The primary endpoint was the presence of organ dysfunction 24 h after blood sampling in the presence of confirmed bacterial versus viral infection. Gene signature performance is reported as area under the receiver operating characteristic curves (AUCs) and 95% CI. FINDINGS: Between Sept 25, 2017, and Oct 27, 2021, 907 patients were enrolled. Blood samples from 595 patients were included in the discovery cohort, and samples from 312 children were included in the RAPIDS validation cohort. We derived a ten-gene disease class signature that achieved an AUC of 94·1% (95% CI 90·6-97·7) in distinguishing bacterial from viral infections in the RAPIDS validation cohort. A ten-gene disease severity signature achieved an AUC of 82·2% (95% CI 76·3-88·1) in predicting organ dysfunction within 24 h of sampling in the RAPIDS validation cohort. Used in tandem, the disease class and disease severity signatures predicted organ dysfunction within 24 h of sampling with an AUC of 90·5% (95% CI 83·3-97·6) for patients with predicted bacterial infection and 94·7% (87·8-100·0) for patients with predicted viral infection. In the external EUCLIDS validation dataset (n=362), the disease class and disease severity predicted organ dysfunction at time of sampling with an AUC of 70·1% (95% CI 44·1-96·2) for patients with predicted bacterial infection and 69·6% (53·1-86·0) for patients with predicted viral infection. INTERPRETATION: In children evaluated for sepsis, novel host transcriptomic signatures specific for bacterial and viral infection can identify dysregulated host response leading to organ dysfunction. FUNDING: Australian Government Medical Research Future Fund Genomic Health Futures Mission, Children's Hospital Foundation Queensland, Brisbane Diamantina Health Partners, Emergency Medicine Foundation, Gold Coast Hospital Foundation, Far North Queensland Foundation, Townsville Hospital and Health Services SERTA Grant, and Australian Infectious Diseases Research Centre.

Achievement of therapeutic antibiotic exposures using Bayesian dosing software in critically unwell children and adults with sepsis.

PURPOSE: Early recognition and effective treatment of sepsis improves outcomes in critically ill patients. However, antibiotic exposures are frequently suboptimal in the intensive care unit (ICU) setting. We describe the feasibility of the Bayesian dosing software Individually Designed Optimum Dosing Strategies (ID-ODS™), to reduce time to effective antibiotic exposure in children and adults with sepsis in ICU. METHODS: A multi-centre prospective, non-randomised interventional trial in three adult ICUs and one paediatric ICU. In a pre-intervention Phase 1, we measured the time to target antibiotic exposure in participants. In Phase 2, antibiotic dosing recommendations were made using ID-ODS™, and time to target antibiotic concentrations were compared to patients in Phase 1 (a pre-post-design). RESULTS: 175 antibiotic courses (Phase 1 = 123, Phase 2 = 52) were analysed from 156 participants. Across all patients, there was no difference in the time to achieve target exposures (8.7 h vs 14.3 h in Phase 1 and Phase 2, respectively, p = 0.45). Sixty-one courses in 54 participants failed to achieve target exposures within 24 h of antibiotic commencement (n = 36 in Phase 1, n = 18 in Phase 2). In these participants, ID-ODS™ was associated with a reduction in time to target antibiotic exposure (96 vs 36.4 h in Phase 1 and Phase 2, respectively, p < 0.01). These patients were less likely to exhibit subtherapeutic antibiotic exposures at 96 h (hazard ratio (HR) 0.02, 95% confidence interval (CI) 0.01-0.05, p < 0.01). There was no difference observed in in-hospital mortality. CONCLUSIONS: Dosing software may reduce the time to achieve target antibiotic exposures. It should be evaluated further in trials to establish its impact on clinical outcomes.

A convergent evolutionary pathway attenuating cellulose production drives enhanced virulence of some bacteria.

Bacteria adapt to selective pressure in their immediate environment in multiple ways. One mechanism involves the acquisition of independent mutations that disable or modify a key pathway, providing a signature of adaptation via convergent evolution. Extra-intestinal pathogenic Escherichia coli (ExPEC) belonging to sequence type 95 (ST95) represent a global clone frequently associated with severe human infections including acute pyelonephritis, sepsis, and neonatal meningitis. Here, we analysed a publicly available dataset of 613 ST95 genomes and identified a series of loss-of-function mutations that disrupt cellulose production or its modification in 55.3% of strains. We show the inability to produce cellulose significantly enhances ST95 invasive infection in a rat model of neonatal meningitis, leading to the disruption of intestinal barrier integrity in newborn pups and enhanced dissemination to the liver, spleen and brain. Consistent with these observations, disruption of cellulose production in ST95 augmented innate immune signalling and tissue neutrophil infiltration in a mouse model of urinary tract infection. Mutations that disrupt cellulose production were also identified in other virulent ExPEC STs, Shigella and Salmonella, suggesting a correlative association with many Enterobacteriaceae that cause severe human infection. Together, our findings provide an explanation for the emergence of hypervirulent Enterobacteriaceae clones.

Prevalence of extra-pulmonary tuberculosis in Africa: A systematic review and meta-analysis.

OBJECTIVE: The burden of extra-pulmonary tuberculosis (EPTB) is not well quantified in TB endemic countries such as those in sub-Saharan Africa. This study aimed to quantify that burden via a systematic review of the prevalence of EPTB in African countries. METHODS: Studies were retrieved by searching five databases; 105 studies published between 1990 and 2023 were included. The studies described the prevalence of EPTB among the general population (4 studies), TB patients (68) and patients with other conditions, including HIV (15), meningitis (3), renal failure (3) and other comorbidities, some of which are cancer (12). Due to the low number of studies reporting EPTB in patients with conditions other than TB, the meta-analysis was performed on studies reporting on EPTB among TB patients (68 studies). Meta-analysis was performed on the 68 studies (271,073 participants) using a random-effects model to estimate the pooled prevalence of EPTB. Meta-regression was used to explore possible explanations for heterogeneity according to regions and time periods. RESULTS: The pooled prevalence of EPTB among TB patients was 26% (95% CI 23-29%). There was substantial heterogeneity of prevalence for the five African regions. The Eastern region had the highest prevalence of 32% (95% CI 28-37%) and the lowest in Western Africa, 16% (95% CI 10-24%). There was no significant difference in the prevalence of EPTB between the 3 eleven-year time periods. CONCLUSIONS: Our systematic review and meta-analysis give insight into the burden of EPTB in Africa. This review could inform clinical and programmatic practices-a higher suspicion index for clinicians and more effort for better services. This could contribute to efforts aiming to end TB, which have historically been focused on PTB.Coordinated efforts that target both EPTB and PTB are needed.

Rapid nanopore sequencing and predictive susceptibility testing of positive blood cultures from intensive care patients with sepsis.

We aimed to evaluate the performance of Oxford Nanopore Technologies (ONT) sequencing from positive blood culture (BC) broths for bacterial identification and antimicrobial susceptibility prediction. Patients with suspected sepsis in four intensive care units were prospectively enrolled. Human-depleted DNA was extracted from positive BC broths and sequenced using ONT (MinION). Species abundance was estimated using Kraken2, and a cloud-based system (AREScloud) provided in silico predictive antimicrobial susceptibility testing (AST) from assembled contigs. Results were compared to conventional identification and phenotypic AST. Species-level agreement between conventional methods and AST predicted from sequencing was 94.2% (49/52), increasing to 100% in monomicrobial infections. In 262 high-quality AREScloud AST predictions across 24 samples, categorical agreement (CA) was 89.3%, with major error (ME) and very major error (VME) rates of 10.5% and 12.1%, respectively. Over 90% CA was achieved for some taxa (e.g., Staphylococcus aureus) but was suboptimal for Pseudomonas aeruginosa. In 470 AST predictions across 42 samples, with both high quality and exploratory-only predictions, overall CA, ME, and VME rates were 87.7%, 8.3%, and 28.4%. VME rates were inflated by false susceptibility calls in a small number of species/antibiotic combinations with few representative resistant isolates. Time to reporting from sequencing could be achieved within 8-16 h from BC positivity. Direct sequencing from positive BC broths is feasible and can provide accurate predictive AST for some species. ONT-based approaches may be faster but significant improvements in accuracy are required before it can be considered for clinical use.IMPORTANCESepsis and bloodstream infections carry a high risk of morbidity and mortality. Rapid identification and susceptibility prediction of causative pathogens, using Nanopore sequencing direct from blood cultures, may offer clinical benefit. We assessed this approach in comparison to conventional phenotypic methods and determined the accuracy of species identification and susceptibility prediction from genomic data. While this workflow holds promise, and performed well for some common bacterial species, improvements in sequencing accuracy and more robust predictive algorithms across a diverse range of organisms are required before this can be considered for clinical use. However, results could be achieved in timeframes that are faster than conventional phenotypic methods.

Implementing paediatric appropriate use criteria for endotracheal suction to reduce complications in mechanically ventilated children with respiratory infections.

BACKGROUND: Endotracheal suction is used to maintain endotracheal tube patency. There is limited guidance to inform clinical practice for children with respiratory infections. OBJECTIVE: The objective of this study was to determine whether implementation of a paediatric endotracheal suction appropriate use guideline Paediatric AirWay Suction (PAWS) is associated with an increased use of appropriate and decreased use of inappropriate suction interventions. METHODS: A mixed-method, pre-implementation-post-implementation study was conducted between September 2021 and April 2022. Suction episodes in mechanically ventilated children with a respiratory infection were eligible. Using a structured approach, we implemented the PAWS guideline in a single paediatric intensive care unit. Evaluation included clinical (e.g., suction intervention appropriateness), implementation (e.g., acceptability), and cost outcomes (implementation costs). Associations between implementation of the PAWS guideline and appropriateness of endotracheal suction intervention use were investigated using generalised linear models. RESULTS: Data from 439 eligible suctions were included in the analysis. Following PAWS implementation, inappropriate endotracheal tube intervention use reduced from 99% to 58%, an absolute reduction (AR) of 41% (95% confidence interval [CI]: 25%, 56%). Reductions were most notable for open suction systems (AR: 48%; 95% CI: 30%, 65%), 0.9% sodium chloride use (AR: 23%; 95% CI: 8%, 38%) and presuction and postsuction manual bagging (38%; 95% CI: 16%, 60%, and 86%; 95% CI: 73%, 99%), respectively. Clinicians perceived PAWS as acceptable and suitable for use. CONCLUSIONS: Implementation of endotracheal tube suction appropriate use guidelines in a mixed paediatric intensive care unit was associated with a large reduction in inappropriate suction intervention use in paediatric patients with respiratory infections.

Neonatal Vascular Access Practice and Complications: An Observational Study of 1,375 Catheter Days.

Vascular access devices play vital roles within neonatal care. We aimed to identify neonatal vascular access device insertion and management practices, and describe the incidence and risk factors for complication development. This is a prospective cohort study of neonates requiring vascular access devices over 3 months in an Australian quaternary-referral neonatal intensive care unit. In addition to describing current practices, primary outcomes were device failure, complications, and skin complications. Results are reported using descriptive statistics and with risk factors calculated via Cox proportional hazards regression. A total of 104 neonates required 302 vascular access devices, over 1375 catheter days. Peripheral intravenous catheters (PIVCs) were most used (n = 186; 62%), followed by umbilical venous catheters (n = 52; 17%). Insertion attempts were often undocumented; but for those recorded, 5% of devices (n = 15) required 4 attempts or more. Device failure occurred in 28% (n = 82), at an incidence rate of 62.5 per 1000 catheter days (95% confidence interval [CI] 49.7-75.9). Failure was most frequent in PIVCs (37%; n = 68), peripheral arterial catheters (33%; n = 2), and peripherally inserted central catheters (20%; n = 6). Infiltration and extravasation were the most frequent cause of PIVC failure (12%; n = 35). A birth weight less than 1500 g was associated with a significant decrease in PIVC failure (hazard ratio 0.58; 95% CI 0.34-0.99).

Application of the ViroKey® SQ FLEX assay for detection of cytomegalovirus antiviral resistance.

BACKGROUND: Cytomegalovirus (CMV) is a viral infection which establishes lifelong latency, often reactivating and causing disease in immunosuppressed individuals, including haematopoietic stem cell transplant (HSCT) recipients. Treatment can be problematic due to antiviral resistance which substantially increases the risk of patient mortality. Diagnostic testing capabilities for CMV antiviral resistance in Australia and elsewhere have traditionally relied on gene-specific Sanger sequencing approaches, however, are now being superseded by next generation sequencing protocols. OBJECTIVE: Provide a snapshot of local mutations and explore the feasibility of the ViroKeyࣨ® SQ FLEX Genotyping Assay (Vela Diagnostics Pty Ltd) by examining sequencing success. METHOD: Performed sequencing on adult (n = 38) and paediatric (n = 81) plasma samples, over a large range of viral loads (above and below the assay recommended threshold of ≥1,000 International Units (IU)/mL; noting most of our paediatric samples have loads <1,000 IU/mL). RESULTS: Eleven test runs (including three repeat runs; 14 to 15 samples per run) were conducted, and four runs were deemed valid. The overall individual sample success rate for the four evaluable test runs was 71.2% (42/59 samples); 80.4% (37/46) samples ≥1,000 IU/mL were valid. Ten clinically important antiviral resistance mutations were detected, the most common being A594V in the UL97 gene, found in 6 (5%) samples. CONCLUSIONS: A range of technical issues were experienced, however with improvement this platform could be a useful addition to routine pathology workflows, providing timely antiviral resistance results for patients undergoing HSCT.

Cytomegalovirus in children undergoing haematopoietic stem cell transplantation: a diagnostic and therapeutic approach to antiviral resistance.

Cytomegalovirus (CMV) is a ubiquitous virus which causes a mild illness in healthy individuals. In immunocompromised individuals, such as children receiving haematopoietic stem cell transplantation, CMV can reactivate, causing serious disease and increasing the risk of death. CMV can be effectively treated with antiviral drugs, but antiviral resistance is an increasingly common complication. Available therapies are associated with adverse effects such as bone marrow suppression and renal impairment, making the choice of appropriate treatment challenging. New agents are emerging and require evaluation in children to establish their role. This review will discuss established and emerging diagnostic tools and treatment options for CMV, including antiviral resistant CMV, in children undergoing haematopoietic stem cell transplant.

A multicentre, retrospective audit of fosfomycin use for urinary tract infections in Australian children and adolescents.

BACKGROUND: Urinary tract infections (UTIs) due to MDR organisms are increasingly common. The lack of paediatric data on efficacious antibiotics makes UTI treatment particularly challenging. Data on the efficacy of fosfomycin use for UTI in children are variable. METHODS: We conducted a retrospective audit of children aged 0-18 years who were treated with fosfomycin for UTI at seven tertiary paediatric hospitals in Australia over a 7 year period, from 2014 to 2020. RESULTS: Ninety-one children with a median age of 5 years (range 2 months to 18 years) received oral fosfomycin for UTI. The majority (57/91, 63%) had one or more comorbidity, with the most common being renal tract anomalies (24/91, 26%). Fifty-nine (65%) had febrile UTI, 14/91 (15%) had pyelonephritis and 1/91 (1%) was bacteraemic. A majority (80/91, 88%) of urinary cultures had an ESBL-producing Gram-negative pathogen isolated. Fosfomycin susceptibility was evident in all 80 isolates tested. For uncomplicated UTI, the most common dose in children aged <1, 1-12 and >12 years was 1, 2 and 3 g, respectively. For complicated UTI, doses of 2 and 3 g were most common. The median duration of fosfomycin administration was 5 days (range 1-82). Clinical cure was achieved in 84/90 (93%); the six with treatment failure had underlying comorbidities. Overall, 2/91 (2%) children experienced drug-related adverse effects comprising gastrointestinal symptoms in both, which resolved after treatment discontinuation. CONCLUSIONS: Fosfomycin is well tolerated and associated with favourable treatment outcomes in children with UTI. Further research on the optimal dosing strategy is required.

Rapid molecular detection of CMY-2, and CTX-M group 1 and 9 variants via recombinase polymerase amplification.

Background: Due to their prevalence worldwide, the ß-lactamases CTX-M and plasmid-mediated CMY-2 are important antimicrobial resistance enzymes in a clinical setting. While culture- and PCR-based detection methods exist for these targets, they are time consuming and require specialist equipment and trained personnel to carry out. Methods: In this study, three rapid diagnostic single-plex and a prototype triplex assay were developed, using recombinase polymerase amplification with lateral flow detection (RPA-LF), and tested for their sensitivity and specificity using two isolate DNA panels (n = 90 and n = 120 isolates). In addition, the RPA-LF assays were also tested with a small number of faecal extract samples (n = 18). Results: The RPA-LF assays were able to detect bla CXT-M-group-1, bla CTX-M-group-9 and bla CMY-2-type variants with high sensitivity (82.1%-100%) and specificity (100%) within a short turnaround time (15-20 min for amplification and detection). Conclusions: RPA-LF assays developed in this study have the potential to be used at or close to the point of care, as well as in low-resource settings, producing rapid results to support healthcare professionals in their treatment decisions.

Detection of Streptococcus pyogenes M1UK in Australia and characterization of the mutation driving enhanced expression of superantigen SpeA.

A new variant of Streptococcus pyogenes serotype M1 (designated 'M1UK') has been reported in the United Kingdom, linked with seasonal scarlet fever surges, marked increase in invasive infections, and exhibiting enhanced expression of the superantigen SpeA. The progenitor S. pyogenes 'M1global' and M1UK clones can be differentiated by 27 SNPs and 4 indels, yet the mechanism for speA upregulation is unknown. Here we investigate the previously unappreciated expansion of M1UK in Australia, now isolated from the majority of serious infections caused by serotype M1 S. pyogenes. M1UK sub-lineages circulating in Australia also contain a novel toxin repertoire associated with epidemic scarlet fever causing S. pyogenes in Asia. A single SNP in the 5' transcriptional leader sequence of the transfer-messenger RNA gene ssrA drives enhanced SpeA superantigen expression as a result of ssrA terminator read-through in the M1UK lineage. This represents a previously unappreciated mechanism of toxin expression and urges enhanced international surveillance.

Evolving insights into the epidemiology of Moraxella species bloodstream infection from two decades of surveillance in Queensland, Australia.

The epidemiology of Moraxella species bloodstream infection (BSI) is poorly defined due to their rarity. We sought to determine the incidence, risk factors, and outcomes of Moraxella species BSI in a large Australian population. All Moraxella species BSIs in patients admitted to Queensland (population estimate 5 million) public health facilities between 2000 and 2019 and submitted to Queensland pathology laboratory-based surveillance were included. Clinical and hospitalisation data were matched with laboratory-based surveillance data. Incidence rate ratios (IRR) with 95% confidence intervals (CI) were calculated. In total, 375 incident Moraxella species BSI occurred during 86 million person-years of surveillance, with an annualised age and sex standardised incidence of 4.3 per million residents. Isolates were most commonly identified as M. catarrhalis (n = 128; 34%) and community-associated (n = 225; 60%). Incidence was highest in infants, with increasing age associated with lower incidence rate. Males were at higher risk (incidence 2.9 vs. 2.0 per million, IRR1.4; 95% CI, 1.2-1.8), this was most pronounced at age extremes. Two-thirds of adults and 43% of children with Moraxella BSI had at least one comorbid illness. When compared to infections in adults, children were more likely to have community-associated disease, and a head and neck source focus of infection. The all-cause 30-day case-fatality rate was 4% (15/375) and this was significantly higher among adults (14/191; 7% vs 1/183; 1%; p < 0.001). Our findings demonstrate the low burden of Moraxella species BSI in a state-wide cohort, for which young children have the highest risk.

Validation of a paediatric sepsis screening tool to identify children with sepsis in the emergency department: a statewide prospective cohort study in Queensland, Australia.

OBJECTIVE: The Surviving Sepsis Campaign guidelines recommend the implementation of systematic screening for sepsis. We aimed to validate a paediatric sepsis screening tool and derive a simplified screening tool. DESIGN: Prospective multicentre study conducted between August 2018 and December 2019. We assessed the performance of the paediatric sepsis screening tool using stepwise multiple logistic regression analyses with 10-fold cross-validation and evaluated the final model at defined risk thresholds. SETTING: Twelve emergency departments (EDs) in Queensland, Australia. PARTICIPANTS: 3473 children screened for sepsis, of which 523 (15.1%) were diagnosed with sepsis. INTERVENTIONS: A 32-item paediatric sepsis screening tool including rapidly available information from triage, risk factors and targeted physical examination. PRIMARY OUTCOME MEASURE: Senior medical officer-diagnosed sepsis combined with the administration of intravenous antibiotics in the ED. RESULTS: The 32-item paediatric sepsis screening tool had good predictive performance (area under the receiver operating characteristic curve (AUC) 0.80, 95% CI 0.78 to 0.82). A simplified tool containing 16 of 32 criteria had comparable performance and retained an AUC of 0.80 (95% CI 0.78 to 0.82). To reach a sensitivity of 90% (95% CI 87% to 92%), the final model achieved a specificity of 51% (95% CI 49% to 53%). Sensitivity analyses using the outcomes of sepsis-associated organ dysfunction (AUC 0.84, 95% CI 0.81 to 0.87) and septic shock (AUC 0.84, 95% CI 0.81 to 0.88) confirmed the main results. CONCLUSIONS: A simplified paediatric sepsis screening tool performed well to identify children with sepsis in the ED. Implementation of sepsis screening tools may improve the timely recognition and treatment of sepsis.

Improving paediatric antimicrobial stewardship in remote and regional Queensland hospitals: development and qualitative evaluation of a tailored intervention for intravenous-to-oral antibiotic switching.

OBJECTIVES: Timely intravenous-to-oral antibiotic switching for children is important for paediatric antimicrobial stewardship (AMS). However, low decision-making confidence and fragmentation of patient care can hamper implementation, with difficulties heightened regionally where AMS programmes for children are lacking. The aim of this study was to develop and evaluate user-led creation and implementation of an intervention package for early intravenous-to-oral switching at regional hospitals in Queensland, Australia. DESIGN: Guided by theory, a four-phase approach was used to: (1) develop multifaceted intervention materials; (2) review materials and their usage through stakeholders; (3) adapt materials based on user-feedback and (4) qualitatively evaluate health workers experiences at 6 months postintervention. SETTING: Seven regional hospitals in Queensland, Australia. PARTICIPANTS: Phase 2 included 15 stakeholders; health workers and patient representatives (patient-guardians and Indigenous liaison officers). Phase 4 included 20 health workers across the seven intervention sites. RESULTS: Content analysis of health worker and parent/guardian reviews identified the 'perceived utility of materials' and 'possible barriers to use'. 'Recommendations and strategies for improvement' provided adjustments for the materials that were able to be tailored to individual practice. Postintervention interviews generated three overarching themes that combined facilitators and barriers to switching: (1) application of materials, (2) education and support, and (3) team dynamics. Overall, despite difficulties with turnover and problems with the medical hierarchy, interventions aided and empowered antibiotic therapy decision-making and enhanced education and self-reflection. CONCLUSIONS: Despite structural barriers to AMS for switching from intravenous-to-oral antibiotics in paediatric patients, offering a tailored multifaceted intervention was reported to provide support and confidence to adjust practice across a diverse set of health workers in regional areas. Future AMS activities should be guided by users and provide opportunities for tailoring tools to practice setting and patients' requirements.

Proof-of-concept, rapid, instrument-free molecular detection of Neisseria gonorrhoeae and ciprofloxacin susceptibility.

OBJECTIVES: To develop instrument-free point-of-care methods using recombinase polymerase amplification (RPA) technology coupled with a simple lateral flow detection system to detect Neisseria gonorrhoeae and susceptibility to ciprofloxacin. METHODS: For identification of gonococcal infection, an RPA-based method was developed targeting the gonococcal porA pseudogene (NG-porA-RPA). For ciprofloxacin susceptibility, predictive WT sequences at codons 91 and 95 of the gonococcal gyrA DNase gene were targeted. Given the known complexities of SNP detection using RPA (e.g. the ability to accommodate mismatches) we trialled several different assays incorporating various additional non-template mismatches in the oligonucleotide sequences to reduce affinity for the mutant (resistant) gyrA sequences. Assays were evaluated using a bank of N. gonorrhoeae (n = 10) and non-gonococcal (n = 5) isolates and a panel of N. gonorrhoeae nucleic acid amplification test (NAAT)-positive clinical sample extracts (n = 40). RESULTS: The NG-porA-RPA assay was specific to N. gonorrhoeae and provided a positive percentage agreement (PPA) of 87.5% (35/40) compared with a commercial N. gonorrhoeae NAAT when applied to the 40 clinical sample extracts. For gyrA, the non-template bases successfully reduced banding intensity for double-mutant strains (mutations at both 91 and 95), but not for rarer single-mutant (91 only) strains. The most promising gyrA assay, NG-gyrA-RPA08, correctly detected 83% (25/30) of infections from NAAT-positive clinical samples confirmed to have WT gyrA sequences based on Sanger sequencing. CONCLUSIONS: These proof-of-concept data show that RPA technology has considerable promise for detecting N. gonorrhoeae and associated antibiotic susceptibility and would offer a diagnostic-based stewardship strategy identified as urgently needed by the WHO.

Patient and economic impact of implementing a paediatric sepsis pathway in emergency departments in Queensland, Australia.

We examined systems-level costs before and after the implementation of an emergency department paediatric sepsis screening, recognition and treatment pathway. Aggregated hospital admissions for all children aged < 18y with a diagnosis code of sepsis upon admission in Queensland, Australia were compared for 16 participating and 32 non-participating hospitals before and after pathway implementation. Monte Carlo simulation was used to generate uncertainty intervals. Policy impacts were estimated using difference-in-difference analysis comparing observed and expected results. We compared 1055 patient episodes before (77.6% in-pathway) and 1504 after (80.5% in-pathway) implementation. Reductions were likely for non-intensive length of stay (- 20.8 h [- 36.1, - 8.0]) but not intensive care (-9.4 h [- 24.4, 5.0]). Non-pathway utilisation was likely unchanged for interhospital transfers (+ 3.2% [- 5.0%, 11.4%]), non-intensive (- 4.5 h [- 19.0, 9.8]) and intensive (+ 7.7 h, [- 20.9, 37.7]) care length of stay. After difference-in-difference adjustment, estimated savings were 596 [277, 942] non-intensive and 172 [148, 222] intensive care days. The program was cost-saving in 63.4% of simulations, with a mean value of $97,019 [- $857,273, $1,654,925] over 24 months. A paediatric sepsis pathway in Queensland emergency departments was associated with potential reductions in hospital utilisation and costs.

Impact of 1-hour and 3-hour sepsis time bundles on patient outcomes and antimicrobial use: A before and after cohort study.

BACKGROUND: Sepsis bundles, promulgated by Surviving Sepsis Campaign have not been widely adopted because of variability in sepsis identification strategies, implementation challenges, concerns about excess antimicrobial use, and limited evidence of benefit. METHODS: A 1-hour septic shock and a 3-hour sepsis bundle were implemented using a Breakthrough Series Collaborative in 14 public hospitals in Queensland, Australia. A before (baseline) and after (post-intervention) study evaluated its impact on outcomes and antimicrobial prescription in patients with confirmed bacteremia and sepsis. FINDINGS: Between 01 July 2017 to 31 March 2020, of 6976 adults presenting to the Emergency Departments and had a blood culture taken, 1802 patients (732 baseline, 1070 post-intervention) met inclusion criteria. Time to antibiotics in 1-hour 73.7% vs 85.1% (OR 1.9 [95%CI 1.1-3.6]) and the 3-hour bundle compliance (48.2% to 63.3%, OR 1.7, [95%CI 1.4 to 2.1]) improved post-intervention, accompanied by a significant reduction in Intensive Care Unit (ICU) admission rates (26.5% vs 17.5% (OR 0.5, [95%CI 0.4 to 0.7]). There were no significant differences in-hospital and 30-day post discharge mortality between the two phases. In a post-hoc analysis of the post-intervention phase, sepsis pathway compliance was associated with lower in-hospital mortality (9.7% vs 14.9%, OR 0.6, 95%CI 0.4 to 0.8). The proportions of appropriate antimicrobial prescription at baseline and post-intervention respectively were 55.4% vs 64.1%, (OR 1.4 [95%CI 0.9 to 2.1]). INTERPRETATION: Implementing 1-hour and 3-hour sepsis bundles for patients presenting with bacteremia resulted in improved bundle compliance and a reduced need for ICU admission without adversely influencing antimicrobial prescription.