Nocardia species distribution and antimicrobial susceptibility within Australia.

BACKGROUND: Nocardia is a ubiquitous saprophyte capable of causing human disease. Disease is primarily respiratory or cutaneous, usually acquired via inhalation or inoculation. Under the influence of environmental and host factors, Nocardia incidence and species distribution demonstrate geographical variation. AIMS: To examine for differences in Nocardia incidence within Western Australia (WA) and analyse species distribution in the context of prior published studies. To analyse antibiogram data from a nationwide passive antimicrobial resistance surveillance program. METHODS: Retrospective extraction of laboratory data for Western Australian Nocardia isolates over a 21-year period. Analysis of Nocardia antimicrobial susceptibility testing data submitted to the Australian Passive Antimicrobial Resistance Surveillance (APAS) program between 2005 and 2022. RESULTS: Nine hundred sixty WA isolates were identified, giving an annual incidence of 3.03 per 100 000 population with apparent latitudinal variation. The four most common species identified within WA and amongst APAS isolates were N. nova, N. cyriacigeorgica, N. brasiliensis and N. farcinica. APAS data demonstrated that all species exhibited high rates of susceptibility to linezolid (100%) and trimethoprim-sulfamethoxazole (98%). Amikacin (>90% susceptibility for all species except N. transvalensis) was the next most active parenteral agent, superior to both carbapenems and third-generation cephalosporins. Susceptibility to oral antimicrobials (other than linezolid) demonstrated significant interspecies variation. CONCLUSIONS: We demonstrate geographical variation in the distribution of Nocardia incidence. Four species predominate in the Australian setting, and nationwide data confirm a high in vitro susceptibility to trimethoprim-sulphamethoxazole and linezolid, justifying their ongoing role as part of first-line empiric therapy.

Scedosporium species and Lomentospora prolificans fungaemia is uniformly fatal in patients with haematological malignancy.

Scedosporium and Lomentospora species are environmental moulds that are virulent in immunocompromised hosts and rarely cause bloodstream infection (BSI). Patients with Scedosporium and Lomentospora species BSI were identified by the state public laboratory service in Queensland, Australia, over a 20-year period. Twenty-two incident episodes occurred among 21 residents; one patient had a second episode 321 days following the first. Of these, 18 were Lomentospora prolificans, three were Scedosporium apiospermum complex and one was a nonspeciated Scedosporium species. Seventeen (81%) patients died during their index admission, and all-cause mortality at 30, 90 and 365 days was 73%, 82% and 91% respectively. All 20 patients with haematological malignancy died within 365 days of follow-up with a median time to death of 9 days (interquartile range, 6-20 days) following diagnoses of BSI.

Aspergillus Species Causing Invasive Fungal Disease in Queensland, Australia.

BACKGROUND: Aspergillus species are important causes of invasive fungal disease, particularly among those with an impaired immune system. Increasing reports have revealed a rising incidence of antifungal drug resistance among Aspergillus spp., particularly among cryptic species. Understanding local antifungal susceptibility patterns is paramount to delivering optimal clinical care. METHODS: Aspergillus spp. recovered from clinical specimens between 2000 and 2021 from Pathology Queensland were collected. Aspergillus spp. were identified routinely morphologically, and where there was ambiguity or a lack of sporulation, by sequencing of the internal transcribed spacer (ITS) region. All Aspergillus spp. that underwent antifungal susceptibility testing according to the CLSI M38-A3 method and were recorded and included in the study. Amphotericin B, voriconazole, posaconazole, isavuconazole, micafungin, caspofungin, and anidulafungin were tested. Pathology Queensland services all public healthcare facilities in Queensland, Australia. RESULTS: 236 Aspergillus spp. were identified from clinical specimens during the study period. The most frequent species identified were Aspergillus section Fumigati (n = 119), Aspergillus section Flavi (n = 35), Aspergillus terreus (n = 32) and Aspergillus niger (n = 29). Overall, MIC50/90 values for voriconazole, posaconazole, itraconazole, and isavuconazole were 0.25/1, 0.25/0.5, 0.25/0.5, and 0.5/2 mg/L respectively. Echinocandins demonstrated low MIC values overall with micafungin and anidulafungin both having an MIC50/90 of 0.015/0.03 mg/L. A total of 15 cryptic species were identified; high triazole MIC values were observed with a voriconazole MIC50/90 of 2/8 mg/L. From 2017 to 2021 we observed an increase in incidence of isolates with high voriconazole MIC values. There was no difference in voriconazole MIC values between Aspergillus spp. acquired in North Queensland when compared to Southeast Queensland, Australia. CONCLUSION: Increasing reports of antifungal resistance among Aspergillus spp. is concerning and warrants further investigation both locally and worldwide. Active surveillance of both the emergence of different Aspergillus spp. and changes in antifungal susceptibility patterns over time is crucial to informing clinicians and treatment guidelines.

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.

Mycoplasma hominis and Ureaplasma urealyticum infections in the immediate post-lung transplant period: A case series and literature review.

Mycoplasma hominis and Ureaplasma species infections in the post-transplant setting are believed to be donor-derived and can be associated with poor outcomes. Difficulty in culturing and identifying these organisms is a significant barrier to diagnosis and early intervention. Tetracyclines, macrolides and fluoroquinolones are the mainstay treatments to cure these infections; however, there are increasing reports of antibiotic resistance. In this case series, we report our single-centre experience with M. hominis and U. urealyticum infection after lung transplantation (9 recipients, all men, mean age 56 years). Delayed diagnosis was common. Young donor age (mean age 23 yrs) and high-risk donor social history (67%) were repeatedly noted in these cases, and all infections were associated with significant morbidity (anastomosis and sternal wound infection, empyema, mediastinitis, pericarditis). Two patients died; with one directly related to Ureaplasma urealyticum infection. In conclusion post lung transplant M. hominis, and U. urealyticum infections are challenging and carry high morbidity. More prospective studies are required to assess the true prevalence, full spectrum of complications and utility of molecular diagnostics to aid early diagnosis and identify antibiotic susceptibility of Mycoplasma and Ureaplasma infections in the post-lung transplant setting.

Novel Human Parechovirus 3 Diversity, Recombination, and Clinical Impact Across 7 Years: An Australian Story.

BACKGROUND: A novel human parechovirus 3 Australian recombinant (HPeV3-AR) strain emerged in 2013 and coincided with biennial outbreaks of sepsis-like illnesses in infants. We evaluated the molecular evolution of the HPeV3-AR strain and its association with severe HPeV infections. METHODS: HPeV3-positive samples collected from hospitalized infants aged 5-252 days in 2 Australian states (2013-2020) and from a community-based birth cohort (2010-2014) were sequenced. Coding regions were used to conduct phylogenetic and evolutionary analyses. A recombinant-specific polymerase chain reaction was designed and utilized to screen all clinical and community HPeV3-positive samples. RESULTS: Complete coding regions of 54 cases were obtained, which showed the HPeV3-AR strain progressively evolving, particularly in the 3' end of the nonstructural genes. The HPeV3-AR strain was not detected in the community birth cohort until the initial outbreak in late 2013. High-throughput screening showed that most (>75%) hospitalized HPeV3 cases involved the AR strain in the first 3 clinical outbreaks, with declining prevalence in the 2019-2020 season. The AR strain was not statistically associated with increased clinical severity among hospitalized infants. CONCLUSIONS: HPeV3-AR was the dominant strain during the study period. Increased hospital admissions may have been from a temporary fitness advantage and/or increased virulence.

Human T-cell leukaemia virus type 1 and Adult T-cell leukaemia/lymphoma in Queensland, Australia: a retrospective cross-sectional study.

OBJECTIVES: Human T-cell leukaemia virus type 1 (HTLV-1), an STI, is reported to be highly prevalent in Indigenous communities in Central Australia. HTLV-1 is an incurable, chronic infection which can cause Adult T-cell leukaemia/lymphoma (ATL). ATL is associated with high morbidity and mortality, with limited treatment options. We studied the prevalence of HTLV-1 and ATL in the state of Queensland, Australia. METHODS: Serum samples stored at healthcare services in Brisbane, Townsville and Cairns and at haemodialysis units in Brisbane (2018-2019) were screened for HTLV-1/2 antibodies using the Abbott ARCHITECT chemiluminescent microparticle immunoassay (CMIA) for antibodies against gp46-I, gp46-II and GD21 (Abbott CMIA, ARCHITECT). Reactive samples were confirmed through Western blot. Pooled Australian National Cancer Registry surveillance data reporting on cases coded for ATL (2004-2015) were analysed. RESULTS: Two out of 2000 hospital and health services samples were confirmed HTLV-1-positive (0.1%, 95% CI 0.02% to 0.4%), both in older women, one Indigenous and one non-Indigenous. All 540 haemodialysis samples tested negative for HTLV. All samples were HTLV-2-negative. Ten out of 42 (24.8%) reported cases of ATL in Australia were from Queensland (crude incidence rate 0.025/100 000; 95% CI 0.011 to 0.045); most cases were seen in adult men of non-Indigenous origin. Nineteen deaths due to ATL were recorded in Australia. CONCLUSION: We confirm that HTLV-1 and ATL were detected in Queensland in Indigenous and non-Indigenous people. These results highlight the need for HTLV-1 prevalence studies in populations at risk of STIs to allow the implementation of focused public health sexual and mother-to-child transmission prevention strategies.

Epidemiology and long-term neurological sequelae of childhood herpes simplex CNS infection.

AIM: Herpes simplex CNS infection is a rare but important cause of neurological disability. Long term outcomes after HSV CNS infection in Australia have not yet been fully described. We sought to provide a comprehensive review of HSV CNS infection in children using a retrospective 13-year evaluation of statewide laboratory and clinical records and a parent survey conducted at least one year after the initial infection. METHODS: All positive PCR HSV 1 and 2 results from cerebrospinal fluid (CSF) or brain tissue were obtained from Queensland pathology providers for children aged 0-16 years between 1 January 2005 and 31 December 2017. Clinical data were obtained from patient records and longer-term outcomes via parent survey at least 1 year after initial infection. RESULTS: Forty-three children were identified over the 13-year period, 17 (39.5%) neonates and 26 (60.4%) non-neonates. The annual incidence for HSV CNS infection in Queensland children aged ≤16 years was 0.3/100 000 (95% confidence intervals (CIs): 0.2-0.4) with neonates at highest risk (incidence 2.5/100 000 live births, 95% CI: 1.5-3.9). HSV 1 was the predominant serotype in both neonates and non-neonates (9/17, 52.9% neonates and 19/26, 73.1% non-neonates). Seven (16.3%) children died, five (5/17, 29.4% neonates), directly attributable to HSV CNS infection (all neonates). Twenty-five (58.1%) had neurological morbidity at discharge (9/17 neonates (52.9%) vs. 16/26 (61.5%) non-neonates) and 20/27 (74.1%) reported long-term neurological morbidity at follow-up (5/9 neonates (55.6%) vs. 15/18 non-neonates (83.3%)). Seven children (two neonates and four non-neonates) with long-term neurological sequelae had no neurological morbidity identified at discharge. CONCLUSION: Significant long-term neurologic sequelae were seen in children with HSV CNS infection even in children with no neurological disability identified at discharge from hospital. Careful neurodevelopmental follow-up of all children is recommended.

Shewanella spp. Bloodstream Infections in Queensland, Australia.

The epidemiology of bloodstream infections caused by Shewanella spp. is not well defined. Our objective was to define the incidence and determinants of Shewanella spp. bloodstream infections by using population-based surveillance in Queensland, Australia during 2000‒2019. The incidence was 1.0 cases/1 million persons annually and was highest during summer and in the tropical Torres and Cape region. Older persons and male patients were at highest risk. At least 1 concurrent condition was documented in 75% of case-patients, and 30-day all cause case-fatality rate was 15%. Aging populations in warm climates might expect an increasing burden of these infections.

Pasteurella species bloodstream infections in Queensland, Australia, 2000-2019.

Pasteurella species are infrequent but potentially severe causes of bloodstream infection (BSI). The objective of this study was to determine the incidence, risk factors, and outcomes of Pasteurella species BSI in a large Australian population. Retrospective, laboratory-based surveillance was conducted in Queensland, Australia (population ≈ 5 million) during 2000-2019, and clinical and outcome information was established by linkage to state hospital admissions and vital statistics databases. During more than 86 million person-years of surveillance, 272 incident Pasteurella species BSI occurred for an overall age- and sex-standardized annual incidence of 3.3 per million residents. The incidence of Pasteurella species BSI was highest in recent years and older individuals were at greatest risk. The median (interquartile range) Charlson Comorbidity Index was 2 (0-4) with scores of zero, 1, 2, and 3 + observed in 81 (30%), 37 (14%), 44 (16%), and 110 (40%) of cases. The 30-day all-cause case fatality was 9% (24/272) and patients who died had more comorbidities and were less likely to have community-associated disease. Although Pasteurella species are infrequent causes of BSI, older individuals and those with comorbidities are at highest risk. The burden of this disease may be expected to increase with an aging and more comorbid population.

Epidemiology of Aeromonas Species Bloodstream Infection in Queensland, Australia: Association with Regional and Climate Zones.

Aeromonas species can cause severe bloodstream infection (BSI) however, few studies have examined their epidemiology in non-selected populations. The objective of this study was to describe the incidence and determinants of Aeromonas species BSI in Queensland, Australia. A retrospective population-based cohort study was conducted during 2000-2019. Aeromonas species BSI were identified by laboratory surveillance and clinical and outcome information through data linkages to statewide databases. A total of 407 incident Aeromonas species BSI were identified with an age- and sex-standardized incidence of 5.2 per million residents annually. No trend in annual incidence rate during two decades of surveillance was demonstrated. Significant variable monthly occurrences were observed with highest rates during warmer, wetter months, and lowest rates during winter and dry periods. There was significant variability in incidence accordingly to region and climate zones, with higher rates observed in tropical north regions and lowest in southeastern corner. The highest incidence was observed in very remote and hot areas in Queensland. Cases were infrequent in children and risk was highest in elderly and males. Seventy-eight patients died within 30 days with a case-fatality rate of 19%. Older age, non-focal infection, higher Charlson score, and monomicrobial bacteremia were independent risk factors for death. Demographic and climatic changes may increase the burden of these infections in future years.

Strategies Used for Implementing and Promoting Adherence to Antibiotic Guidelines in Low- and Lower-Middle-Income Countries: A Systematic Review.

Containing antimicrobial resistance and reducing high levels of antibiotic consumption in low- and lower middle-income countries are a major challenge. Clinical guidelines targeting antibiotic prescribing can reduce consumption, however, the degrees to which clinical guidelines are adopted and adhered to are challenging for developers, policy makers and users. The aim of this study was to review the strategies used for implementing and promoting antibiotic guideline adherence in low- and lower middle-income countries. A review of published literature was conducted using PubMed, Cochrane Library, SCOPUS and the information systems of the World Health Organization and the Australian National University according to PRISMA guidelines and our PROSPERO protocol. The strategies were grouped into five broad categories based on the Cochrane Effective Practice and Organization of Care taxonomy. The 33 selected studies, representing 16 countries varied widely in design, setting, disease focus, methods, intervention components, outcomes and effects. The majority of interventions were multifaceted and resulted in a positive direction of effect. The nature of the interventions and study variability made it impossible to tease out which strategies had the greatest impact on improving CG compliance. Audit and feedback coupled with either workshops and/or focus group discussions were the most frequently used intervention components. All the reported strategies are established practices used in antimicrobial stewardship programs in high-income countries. We recommend interrupted time series studies be used as an alternative design to pre- and post-intervention studies, information about the clinical guidelines be made more transparent, and prescriber confidence be investigated.

Granulicatella adiacens: An uncommon diagnosis of prosthetic hip joint infection. A case report with review of the literature.

We report a case of prosthetic hip infection in a 79 year old man caused by Granulicatella adiacens. The diagnosis was achieved using broad range 16S PCR gene analysis at an early stage, after joint aspiration and culture failed to yield a pathogen. Staged revision surgery together with administration of appropriate antibiotics resulted in cure. Granulicatella adiacens is a nutritionally variant streptococcus (NVS). It has been increasingly reported to cause significant morbidities involving various systems. Its insidious growth due to complex growth requirements, has made its diagnosis challenging, and often delays appropriate antibiotic administration.

Rapid detection of NDM and VIM carbapenemase encoding genes by recombinase polymerase amplification and lateral flow-based detection.

Carbapenemase-producing organisms (CPOs) pose a serious clinical threat and rapid detection tools are essential to aid in patient management. We developed rapid and simple molecular tests to detect blaNDM-type and blaVIM-type carbapenemase genes using recombinase polymerase amplification (RPA) combined with a lateral flow detection. The tests could provide results in approximately 15 min when using DNA extracts, with limits of detection of 9.2 copies/µl for the blaNDM-type assay and 7.5 copies/µl for blaVIM-type assay, and successfully detected all isolates harbouring the carbapenemase encoding genes in a panel of 57 isolates. These RPA tests may be suitable for use in low-resource settings to tailor rapid implementation of infection control precautions and antibiotic stewardship.

Herpes Simplex Virus Infection in Infants: 13 Year Evaluation (2005-2017) of Laboratory Confirmed Cases in Queensland, Australia.

BACKGROUND: National neonatal surveillance for herpes simplex virus (HSV) disease suggests that the incidence of HSV disease may be higher in Queensland (QLD) than in other Australian States. We sought to investigate the incidence via a retrospective 13-year evaluation of statewide laboratory data, autopsy data and linked clinical records of infants with laboratory confirmed infection. METHODS: All positive polymerase chain reaction HSV 1 and 2 results were obtained for infants 0-3 months of age from January 1, 2005 to December 31, 2017. Clinical data were obtained from patient records and parent questionnaires were used to evaluate long-term sequelae. RESULTS: One hundred seventy-two infants with HSV positive polymerase chain reaction results: 121 (70.3%) with HSV 1. Of 104 (60.5%) infants with signs of HSV disease, 76 (73.1%) were neonates (≤28 days of age) [incidence 9.6 (95% confidence interval, 7.0-11.5) per 100,000 live births] and 28 (26.9%) were young infants (29-90 days of age) [3.6 (95% confidence interval, 2.4-5.4) per 100,000 live births]. The annual incidence of neonatal HSV disease increased significantly in Queensland over the study period (P < 0.01). Of the 76 neonates with HSV disease, 58 (76.3%) presented with the skin, eye, mouth (SEM) disease, 17 (22.4%) with HSV encephalitis and 11 (14.5%) had disseminated disease. Young infants presented with HSV skin, eye, mouth disease (21, 75.0%) or HSV encephalitis (6, 21.4%). Death occurred in 12/104 (11.5%) infants (all neonates) with 10 attributable to HSV disease. CONCLUSION: The incidence of neonatal HSV disease in QLD is almost 3 times the national reported incidence. Further research is being undertaken to explore reasons for this change and implications for practice.

Testing for Common Respiratory Viruses in Children Admitted to Pediatric Intensive Care: Epidemiology and Outcomes.

OBJECTIVES: Viral infections are common in children, but there is a lack of data on severe viral infections in critically ill children. We investigated testing for viral infections in children requiring PICU admission and describe the epidemiology and outcomes. DESIGN: Multicenter retrospective study. Results of viral testing for nine respiratory viruses using polymerase chain reaction were collected. PARTICIPANTS: Children less than 16 years old nonelectively admitted to PICU over a 6-year period. SETTING: Two tertiary PICUs in Queensland, Australia. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Primary outcome was PICU length of stay. Secondary outcomes included need for and duration of intubation and mortality in PICU. Univariate and multivariate regression analyses were performed, adjusting for age, indigenous status, comorbidities, and severity of illness. RESULTS: Of 6,426 nonelective admissions, 2,956 (46%) were polymerase chain reaction tested for a virus of which 1,353 (46%) were virus positive. Respiratory syncytial virus was the most common pathogen identified (n = 518, 33%), followed by rhinovirus/enterovirus and adenovirus. Across all patients who underwent polymerase chain reaction testing, identification of a respiratory virus was not significantly associated with longer overall length of stay (multivariate odds ratio, 1.08; 95% CI, 0.99-1.17; p = 0.068) or longer intubation (p = 0.181), whereas the adjusted odds for intubation and mortality were significantly lower (p < 0.01). Subgroup analyses restricted to patients with acute respiratory infections (n = 1,241), bronchiolitis (n = 761), pneumonia (n = 311), confirmed bacterial infection (n = 345), and malignancy (n = 95) showed that patients positive for a virus on testing had significantly longer PICU length of stay (multivariate p < 0.05). In children with pneumonia, identification of a respiratory virus was associated with significantly increased duration of ventilation (p = 0.003). No association between positive test results for multiple viruses and outcomes was observed. CONCLUSION: Viral infections are common in critically ill children. Viral infections were associated with lower intubation and mortality rates compared with all children testing negative for viral infections. In several subgroups studied, identification of viral pathogens was associated with longer PICU length of stay while mortality was comparable. Prospective studies are required to determine the benefit of routine testing for respiratory viruses at the time of PICU admission.

Integrating multiple genomic technologies to investigate an outbreak of carbapenemase-producing Enterobacter hormaechei.

Carbapenem-resistant Enterobacteriaceae (CRE) represent an urgent threat to human health. Here we report the application of several complementary whole-genome sequencing (WGS) technologies to characterise a hospital outbreak of blaIMP-4 carbapenemase-producing E. hormaechei. Using Illumina sequencing, we determined that all outbreak strains were sequence type 90 (ST90) and near-identical. Comparison to publicly available data linked all outbreak isolates to a 2013 isolate from the same ward, suggesting an environmental source in the hospital. Using Pacific Biosciences sequencing, we resolved the complete context of the blaIMP-4 gene on a large IncHI2 plasmid carried by all IMP-4-producing strains across different hospitals. Shotgun metagenomic sequencing of environmental samples also found evidence of ST90 E. hormaechei and the IncHI2 plasmid within the hospital plumbing. Finally, Oxford Nanopore sequencing rapidly resolved the true relationship of subsequent isolates to the initial outbreak. Overall, our strategic application of three WGS technologies provided an in-depth analysis of the outbreak.

Genomic analysis of carbapenemase-producing Enterobacteriaceae in Queensland reveals widespread transmission of blaIMP-4 on an IncHI2 plasmid.

Carbapenemase-producing Enterobacteriaceae (CPE) are an increasingly common cause of healthcare-associated infections and may occasionally be identified in patients without extensive healthcare exposure. blaIMP-4 is the most frequently detected carbapenemase gene in Enterobacteriaceae within Australia, but little is known about the mechanisms behind its persistence. Here we used whole genome sequencing (WGS) to investigate the molecular epidemiology of blaIMP-4 in Queensland, Australia. In total, 107 CPE were collected between 2014 and 2017 and sent for WGS on an Illumina NextSeq500. Resistance genes and plasmid types were detected using a combination of read mapping and nucleotide comparison of de novo assemblies. Six isolates were additionally sequenced using Oxford Nanopore MinION to generate long-reads and fully characterize the context of the blaIMP-4 gene. Of 107 CPE, 93 carried the blaIMP-4 gene; 74/107 also carried an IncHI2 plasmid, suggesting carriage of the blaIMP-4 gene on an IncHI2 plasmid. Comparison of these isolates to a previously characterized IncHI2 plasmid pMS7884A (isolated from an Enterobacter hormaechei strain in Brisbane) suggested that all isolates carried a similar plasmid. Five of six representative isolates sequenced using Nanopore long-read technology carried IncHI2 plasmids harbouring the blaIMP-4 gene. While the vast majority of isolates represented E. hormaechei, several other species were also found to carry the IncHI2 plasmid, including Klebsiella species, Escherichia coli and Citrobacter species. Several clonal groups of E. hormaechei were also identified, suggesting that persistence of blaIMP-4 is driven by both presence on a common plasmid and clonal spread of certain E. hormaechei lineages.

Paediatric intensive care admissions during the 2015-2016 Queensland human parechovirus outbreak.

AIM: The human parechovirus (HPeV) has emerged as a pathogen causing sepsis-like presentations in young infants, but there is a lack of data on HPeV presentations requiring intensive care support. We aimed to characterise the clinical presentation, disease severity, management and outcome of a population-based cohort of children with microbiologically confirmed HPeV infection requiring admission to paediatric intensive care units (PICUs) in Queensland, Australia during a recent outbreak. METHODS: This was a multicentre retrospective study of children admitted to PICU between 1 January 2015 and 31 December 2016 with confirmed HPeV infection. RESULTS: Thirty infants (median age 20 days) with HPeV genotype 3 were admitted to PICU, representing 16% of all children with HPeV admitted to hospital and 6.4% of non-elective PICU admissions in children <1 year of age. Children requiring PICU admission were younger than children admitted to hospital (P = 0.001). Apnoea, haemodynamic instability with tachycardia and seizures represented the main reasons for PICU admission. Eleven children (37%) required mechanical ventilation for a median duration of 62 h, 22 (73%) received fluid boluses and 7 (23%) were treated with vasoactive agents for a median duration of 53 h. Median length of stay was 2.62 days. A total of 24 children (80%) fulfilled sepsis criteria, 14 (47%) severe sepsis and 7 (23%) septic shock criteria. Eight (27%) had abnormal brain magnetic resonance imaging. No patient died. CONCLUSIONS: We confirm that HPeV infection is an important cause of sepsis-like syndrome in infants with substantial associated morbidity. Optimal management and long-term outcomes require further investigation.

Viral Respiratory Infections Diagnosed After PICU Admission.

OBJECTIVES: Reduction of nosocomial infections represents an increasingly recognized aspect of PICU benchmarking. We investigated the prevalence and outcomes of viral respiratory infections acquired during admission to PICU. DESIGN: Multicenter, statewide retrospective linkage study. SETTING: Tertiary PICU. PATIENTS: All children less than 16 years requiring PICU admission for greater than 48 hours from January 1, 2008, until December 31, 2013. INTERVENTION: Testing was performed in symptomatic patients using an extended panel polymerase chain reaction capturing nine respiratory viruses. Duration of intubation and total duration of respiratory support were primary outcomes. MEASUREMENTS AND MAIN RESULTS: Of 3,607 patients admitted to PICU for greater than 48 hours, 102 (2.8%) were diagnosed with a PICU-associated viral infection out of 702 patients (19.4%) undergoing viral testing, reflecting a rate of 2.8 PICU-associated viral infections per 1,000 PICU patient days. Compared with negative/untested patients, those with PICU-associated viral infections had greater intubation duration (median 164 vs 67; p< 0.001), longer respiratory support (204 vs 68 hr; p < 0.001), were more likely to require extracorporeal life support (odds ratio, 5.3; 2.7-10.3; p < 0.001), high-frequency oscillatory ventilation (odds ratio, 3.0; 1.7-5.4; p < 0.001), and inhaled nitric oxide (odds ratio, 2.7; 1.5-5.0; p = 0.001). When comparing patients with PICU-associated viral infection with patients who tested negative for respiratory viruses, no substantial difference in these outcomes was found. CONCLUSIONS: The acquisition of viral infections during PICU admission is less frequent compared with previous reports on bacterial and fungal hospital-acquired infections. We did not observe worse patient-centered outcomes when comparing virus positive versus tested but negative patients. Our findings challenge the clinical value of performing viral respiratory diagnostics in PICU patients evaluated for infection.