Epidemiology of biliary tract-associated bloodstream infections and adequacy of empiric therapy: an Australian population-based study.

PURPOSE: Although the biliary tract is a common source of invasive infections, the epidemiology of cholangitis- and cholecystitis-associated bloodstream infection (BSI) is not well defined. The objective of this study was to determine the incidence, clinical determinants, microbiology of biliary tract-associated BSI, and predicted adequacy of common empiric therapy regimens. METHODS: All biliary tract-associated BSI in Queensland during 2000-2019 were identified using state-wide data sources. Predicted adequacy of empiric antimicrobial therapy was determined according to microbiological susceptibility data. RESULTS: There were 3,698 episodes of biliary tract-associated BSI occurred in 3,433 patients of which 2,147 (58.1%) episodes were due to cholangitis and 1,551 (41.9%) cholecystitis, for age- and sex-standardized incidence rates of 2.7, and 2.0 per 100,000 population, respectively. An increasing incidence of biliary tract-associated BSI was observed over the study that was attributable to an increase in cholangitis cases. There was a significant increased risk for biliary tract-associated BSI observed with advancing age and male sex. Patients with cholangitis were older, more likely to have healthcare associated infection, and have more comorbidities most notably liver disease and malignancies as compared to patients with cholecystitis. The distribution of infecting pathogens was significantly different with polymicrobial aetiologies more commonly observed with cholangitis (18.4% vs. 10.5%; p < 0.001). The combination of ampicillin/gentamicin/metronidazole was predicted to have the overall highest adequacy (96.1%), whereas amoxicillin/clavulanate had the lowest (77.0%). Amoxicillin/clavulanate (75.2% vs. 79.4%, p:0.03) and ceftriaxone/metronidazole (83.4% vs. 89.6%; p < 0.001) showed significantly inferior predicted adequacy for cholangitis as compared to cholecystitis. CONCLUSIONS: Bloodstream infections related to cholecystitis and cholangitis exhibit different epidemiology, microbiology, and requirements for empiric therapy.

The effect of climate on melioidosis incidence in Townsville, Australia: a dry tropical region.

BACKGROUND: Townsville is in the dry tropics in Northern Australia and an endemic region for melioidosis. Melioidosis is an infectious disease caused by Burkholderia pseudomallei, a soil dwelling organism. The incidence of melioidosis is associated with high levels of rainfall and has been linked to multiple weather variables in other melioidosis endemic regions such as in Darwin. In contrast to Townsville, Darwin is in the wet-dry tropics in Northern Australia and receives 40% more rainfall. We assessed the relationship between melioidosis incidence and weather conditions in Townsville and compared the patterns to the findings in Darwin and other melioidosis endemic regions. METHOD: Performing a time series analysis from 1996 to 2020, we applied a negative binomial regression model to evaluate the link between the incidence of melioidosis in Townsville and various weather variables. Akaike's information criterion was used to assess the most parsimonious model with best predictive performance. Fourier terms and lagged deviance residuals were included to control long term seasonal trends and temporal autocorrelation. RESULTS: Humidity is the strongest predictor for melioidosis incidence in Townsville. Furthermore, the incidence of melioidosis showed a three-times rise in the Townsville region when >200 mm of rain fell within the fortnight. Prolonged rainfall had more impact than a heavy downpour on the overall melioidosis incident rate. There was no statistically significant increase in incidence with cloud cover in the multivariable model. CONCLUSION: Consistent with other reports, melioidosis incidence can be attributed to humidity and rainfall in Townsville. In contrast to Darwin, there was no strong link between melioidosis cases and cloud cover and nor single large rainfall events.

Burkholderia pseudomallei Clinical Isolates Are Highly Susceptible In Vitro to Cefiderocol, a Siderophore Cephalosporin.

Cefiderocol is a cephalosporin designed to treat multidrug-resistant Gram-negative infections. By forming a chelated complex with ferric iron, cefiderocol is transported into the periplasmic space via bacterial iron transport systems and primarily binds to penicillin-binding protein 3 (PBP3) to inhibit peptidoglycan synthesis. This mode of action results in cefiderocol having greater in vitro activity against many Gram-negative bacilli than currently used carbapenems, ß-lactam/ß-lactamase inhibitor combinations, and cephalosporins. Thus, we investigated the in vitro activity of cefiderocol against a total of 246 clinical isolates of Burkholderia pseudomallei from Queensland, Australia. The collection was composed primarily of bloodstream (56.1%), skin and soft tissue (16.3%), and respiratory (15.9%) isolates. MICs of cefiderocol ranged from ≤0.03 to 16 mg/liter, whereas the MIC90 was 0.125 mg/liter. Based upon CLSI clinical breakpoints for cefiderocol against Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia, three isolates (1.2%) would be classified as nonsusceptible (MIC > 4 mg/liter). Using EUCAST non-species-specific (pharmacokinetic/pharmacodynamic [PK/PD]) clinical breakpoints or those set for Pseudomonas aeruginosa, four isolates (1.6%) would be resistant (MIC > 2 mg/liter). Further testing for coresistance to meropenem, ceftazidime, trimethoprim-sulfamethoxazole, amoxicillin-clavulanate, and doxycycline was performed on the four isolates with elevated cefiderocol MICs (>2 mg/liter); all isolates exhibited resistance to amoxicillin-clavulanic acid, while three isolates also displayed resistance to at least one other antimicrobial. Cefiderocol was found to be highly active in vitro against B. pseudomallei primary clinical isolates. This compound shows great potential for the treatment of melioidosis in countries of endemicity and should be explored further.

Laboratory Safety: Handling Burkholderia pseudomallei Isolates without a Biosafety Cabinet.

Burkholderia pseudomallei is a tier 1 select agent that is associated with laboratory-acquired melioidosis, with international guidelines recommending isolate handling within a class II biosafety cabinet (BSC) in a biosafety level 3 (BSL3) facility. In low-resource settings, this may not be practical; therefore, we aimed to assess the risk of laboratory-acquired melioidosis during routine work. Prior exposure to the organism was determined with a questionnaire and concomitant serology. Of 30 laboratory scientists handling B. pseudomallei on 1,267 occasions outside a biosafety cabinet, no infections were documented and all participants remained seronegative. Additionally, we performed controlled environmental air sampling during 78 laboratory handling events, including plate opening, oxidase testing, and McFarland suspension creation. None of the experiments demonstrated aerosolization of the organism. This study suggests the risk of laboratory-acquired melioidosis is low. However, individual laboratories will need to undertake a risk assessment, including melioidosis endemicity, availability of resources for containment, the nature of routine handling to be undertaken, and the presence of predisposing risk factors for infection in the staff concerned. Additionally, laboratories should take region-specific guidelines into consideration. Further research is required to better inform on the overall risk of infection in the microbiology laboratory.

A multi-country study using MALDI-TOF mass spectrometry for rapid identification of Burkholderia pseudomallei.

BACKGROUND: Burkholderia pseudomallei is the bacterial causative agent of melioidosis, a difficult disease to diagnose clinically with high mortality if not appropriately treated. Definitive diagnosis requires isolation and identification of the organism. With the increased adoption of MALDI-TOF MS for the identification of bacteria, we established a method for rapid identification of B. pseudomallei using the Vitek MS, a system that does not currently have B. pseudomallei in its in-vitro diagnostic database. RESULTS: A routine direct spotting method was employed to create spectra and SuperSpectra. An initial B. pseudomallei SuperSpectrum was created at Shoklo Malaria Research Unit (SMRU) from 17 reference isolates (46 spectra). When tested, this initial SMRU SuperSpectrum was able to identify 98.2 % (54/55) of Asian isolates, but just 46.7 % (35/75) of Australian isolates. Using spectra (430) from different reference and clinical isolates, two additional SMRU SuperSpectra were created. Using the combination of all SMRU SuperSpectra with seven existing SuperSpectra from Townsville, Australia 119 (100 %) Asian isolates and 31 (100 %) Australian isolates were correctly identified. In addition, no misidentifications were obtained when using these 11 SuperSpectra when tested with 34 isolates of other bacteria including the closely related species Burkholderia thailandensis and Burkholderia cepacia. CONCLUSIONS: This study has established a method for identification of B. pseudomallei using Vitek MS, and highlights the impact of geographical differences between strains for identification using this technique.

Antimicrobial stewardship in diabetic ketoacidosis: a single-centre experience.

BACKGROUND: Diabetic ketoacidosis (DKA) is a common and serious complication arising predominantly in patients with type 1 diabetes mellitus. International data demonstrate that infection is one of the most common precipitating causes of DKA. Currently there are limited data regarding the role of antimicrobial stewardship (AMS) in this setting. AIM: To provide epidemiologic data regarding infections precipitating DKA, microbiological aetiology and antimicrobial prescribing practices in order to inform AMS interventions. METHODS: Retrospective chart review of all type 1 diabetes mellitus DKA presentations from May 2015 to June 2018. RESULTS: In total, 249 DKA presentations occurred in 111 patients. Suspected infection accounted for 100/249 (40%) presentations, and only 36/249 (14.5%) were proven or probable infections. Skin and soft tissue infection was the most common (9/36, 25%), followed by urinary tract infection (8/36, 22%) and respiratory tract infection (7/36, 19%). A pathogen was identified in 24/100 presumed infections and included Staphylococcus aureus (24, 46%), Klebsiella pneumoniae (4/24, 17%) and Escherichia coli (3/24, 13%). No viral pathogens were identified. Of 80 empirical antimicrobial prescriptions, 75% were inappropriate based on guideline management of the documented suspected infection. Single agent ceftriaxone was appropriately prescribed in 7/23 (30%) cases, and was most frequently prescribed overall 23/80 (29%). CONCLUSION: This study demonstrates a lower incidence of infection compared to most previous publications, and suggests that infection-precipitated DKA may be over reported. Furthermore, our findings provide support for the role of AMS in the management of DKA.

Retrospective Review of Treponema pallidum PCR and Serology Results: Are Both Tests Necessary?

There has been a resurgence of syphilis diagnoses in Australia. We investigated whether our Treponema pallidum PCR test provides any additional diagnostic information over syphilis serology (chemiluminescence immunoassay [CMIA], Treponema pallidum particle agglutination [TPPA] assay, and the rapid plasma reagin [RPR] flocculation test). A retrospective audit of all T. pallidum PCR requests that came through our laboratory from January 2010 to June 2017 was conducted; data collected included age, gender, site of swab, and results from T. pallidum PCR, syphilis serology, and herpes simplex virus 1 (HSV-1) and HSV-2 PCRs. A total of 441 T. pallidum PCR tests were performed; on average, 3 T. pallidum PCRs per month were requested in 2011, and this rate increased to 17.2 requests per month in 2017. A total of 323 patients had both T. pallidum PCR and syphilis serology performed, with 67% of swabs taken from the genitals. T. pallidum PCR gave positive results for 61/323 (19%) patients; of these 61 patients, 59 (97%) also had positive syphilis serology results (T. pallidum PCR sensitivity, 68%; specificity, 99%; positive predictive value, 97%; negative predictive value, 89%). Syphilis serology was positive for 91/323 patients (28%); of these 91 patients, 61 (66%) were also T. pallidum PCR positive (syphilis serology sensitivity, 97%; specificity, 88%; positive predictive value, 60%; negative predictive value, 99%). The Cohen's kappa value was 0.74, indicating substantial agreement between the two tests. Our results show that most patients with positive T. pallidum PCR results also had positive syphilis serology. Therefore, T. pallidum PCR adds little clinical value over serology for the diagnosis of syphilis in certain clinical settings.

Cryptococcal infections over a 15 year period at a tertiary facility & impact of guideline management.

Cryptococcosis is an invasive fungal infection caused primarily by Cryptococcus neoformans and Cryptococcus gattii species, presenting predominantly as meningoencephalitis. The aim of this study is to assess all cryptococcal infections managed at our facility from 2001 to 2015 to determine incidence, risk factors, and comparison of outcomes prior to and following introduction of the 2010 Infectious Disease Society of America (IDSA) guidelines. Retrospective analysis of all patients diagnosed and treated for cryptococcal infection occurring between January 2001 and December 2015. Of 102 patients diagnosed with cryptococcal infection, 97 were eligible for study inclusion. There appears to be an overall increased incidence of cryptococcosis in both transplant and non-transplant cohorts with a peak in 2015 of 6 transplant and 13 non-transplant cases. In the meningitis cohort, 38/52 (73%) of identified isolates were C. neoformans, and 14/52 (27%) were C. gattii. Notably, 14/14 (100%) of C. gattii isolates were associated with meningitis, as compared to only 38/64 (59%) C. neoformans associated with meningitis (P: .003). It appears that patients presenting with cough are less likely to have meningitis, 17/27 (63%), (P: .005). When stratifying for culture positive meningitis lumbar puncture opening pressure, the median in the culture positive cohort was 31.5 cm H2 O compared with 15.5 cm H2 O (P: .036).Multiple admissions were required prior to diagnosis in the majority of cases with only 18/72 (25%) diagnosed on 1st presentation. Postguideline mortality has improved from 15% to 6.1% (P: .046). Cryptococcal infection remains relatively uncommon, but there appears to be an increasing trend in incidence. Overall mortality is relatively low and has improved since introduction of the 2010 IDSA guidelines.

Cryptococcal infections in solid organ transplant recipients over a 15-year period at a state transplant center.

BACKGROUND: The aim of this research paper was to determine the incidence, risk factors, and clinical outcome of solid organ transplant (SOT) recipients diagnosed and treated for cryptococcosis at our institution. METHODS: Retrospective analysis of all patients with SOT diagnosed and treated for cryptococcal infection occurring between January 2001 and December 2015. RESULTS: Of 102 patients diagnosed with cryptococcal infection, 23 were SOT recipients. Renal transplant accounted for 22/23 cases, of which 13 had meningitis. The annual incidence of infection has risen significantly, and is now greater than 2/1000 prevalent renal transplant recipients. As expected, biochemical factors associated with meningitis include lower glucose on cerebrospinal fluid (CSF) analysis, median 2.4 vs 4.5 mmol/L (P=.02); CSF white blood cell median 50 vs 1/µL (P<.001); CSF protein, median 950 vs 335 mg/L (P=.04). Serum cryptococcal antigen titers were higher in the meningitis cohort, median 512 vs 32 (P=.03). Clinically, headache on admission (odds ratio: 9 [1.29-63.03], P=.03) and a prolonged length of stay (median of 36 vs 13 days) in the meningitis cohort (P=.02) were significant. CONCLUSION: Cryptococcal infection in SOT recipients remains rare; however, there has been a marked increase in cases since 2014. This study reveals a need for increased vigilance for a potential emerging infectious disease. It furthermore highlights the need for ongoing research to further aid early diagnosis, prognostication, management, and screening cost-effectiveness.

Ureaplasma urealyticum necrotizing soft tissue infection.

Ureaplasma urealyticum is a urogenital commensal and often associated with localised infection. With the advent of monoclonal immunosuppressive therapy and improved diagnostic methods, reports of non-urogenital infections are accumulating. We report a rare case of U. urealyticum necrotizing soft tissue infection and left hip septic arthritis in a hypogammaglobulinaemic patient. Consideration of this organism as an etiological agent, and potential early use of nucleic-acid diagnostic investigation with empiric therapy including activity against Ureaplasma in this patient population may be warranted.

Haematologic and Urologic Manifestations of Cryptococcus neoformans.

Cryptococcus neoformans classically causes pulmonary and central nervous system (CNS) infection in immunocompromised hosts and can lead to disseminated disease. Two cases of atypical cryptococcal infection are presented-an elderly Human Immunodeficiency Virus- (HIV-) negative male with a urinary source of infection and a young HIV-positive male with bone marrow infiltration complicated by haemophagocytic lymphohistiocytosis (HLH). A literature review of systemic cryptococcal infections involving the genitourinary tract and bone marrow was performed. These cases highlight the importance of clinicians considering uncommon manifestations of cryptococcal disease.

The Genomic Epidemiology of Clinical Burkholderia pseudomallei Isolates in North Queensland, Australia.

Background:Burkholderia pseudomallei, the causative agent of melioidosis, is highly genetically recombinant, resulting in significant genomic diversity. Multiple virulence factors have been associated with specific disease presentations. To date, there are limited data relating to genomic diversity and virulence factors associated with melioidosis cases in North Queensland, Australia. Aim: To describe the genetic diversity of B. pseudomallei and identify virulence factors associated with clinical risk factors and patient outcomes. Methods: Whole genome sequencing of clinical isolates was performed and analysed with clinical data obtained from a retrospective melioidosis cohort study. Results: Fifty-nine distinct sequence types (STs) were identified from the 128 clinical isolates. Six STs comprised 64/128 (50%) isolates. Novel STs accounted for 38/59 (64%) STs, with ST TSV-13 as the most prevalent (n = 7), and were less likely to possess an LPS A genotype or YLF gene cluster (p < 0.001). These isolates were most likely to be found outside the inner city (aOR: 4.0, 95% CI: 1.7-9.0, p = 0.001). ST TSV-13 was associated with increased mortality (aOR: 6.1, 95% CI: 1.2-30.9, p = 0.03). Patients with a history of alcohol excess were less likely to be infected by fhaB3 (aOR 0.2, 95% CI: 0.1-0.7, p = 0.01) or YLF (aOR: 0.4, 95% CI: 0.2-0.9, p = 0.04) positive isolates. Conclusions: There are a significant number of novel sequence types in Townsville, Australia. An emerging novel ST appears to have an association with geographic location and mortality. Ongoing investigation is required to further understand the impact of this ST on the Townsville region.

First report of probable neurobrucellosis in Australia.

We report the first known Australian case of probable neurobrucellosis, in a young feral-pig shooter who presented with episodic left-sided visual loss and left-sided numbness and headache. Treatment with intravenous ceftriaxone and oral rifampicin, doxycycline and trimethoprim­sulfamethoxazole resulted in a good clinical response.

Melioidosis Queensland: An analysis of clinical outcomes and genomic factors.

BACKGROUND: The clinical and genomic epidemiology of melioidosis varies across regions. AIM: To describe the clinical and genetic diversity of B. pseudomallei across Queensland, Australia. METHODS: Whole genome sequencing of clinical isolates stored at the melioidosis reference lab from 1996-2020 was performed and analysed in conjunction with available clinical data. RESULTS: Isolates from 292 patients were analysed. Bacteraemia was present in 71% and pneumonia in 65%. The case-fatality rate was 25%. Novel sequence types (ST) accounted for 51% of all isolates. No association was identified between the variable virulence factors assessed and patient outcome. Over time, the proportion of First Nation's patients declined from 59% to 26%, and the proportion of patients aged >70 years rose from 13% to 38%. CONCLUSION: This study describes a genomically diverse and comparatively distinct collection of B. pseudomallei clinical isolates from across Queensland, Australia. An increasing incidence of melioidosis in elderly patients may be an important factor in the persistently high case-fatality in this region and warrants further investigation and directed intervention.

Expanding the Geographic Boundaries of Melioidosis in Queensland, Australia.

Melioidosis is an infectious disease caused by the bacterium Burkholderia pseudomallei. Although this environmental organism is endemic in certain regions of Australia, it is not considered endemic in Southern Queensland, where the last case was reported 21 years ago. We report a climate change-associated outbreak of melioidosis occurring during two La Niña events in a region previously considered nonendemic for B. pseudomallei. During a 15-month period, 14 cases of locally acquired melioidosis were identified. Twelve patients were adults (> 50 years), with diabetes mellitus the most common risk factor in 6 of 12 patients (50%). Eleven patients (79%) had direct exposure to floodwaters or the flooded environment. This study suggests an association between climate change and an increased incidence of melioidosis. In addition, this is the first report of environmental sampling and whole-genome analysis to prove endemicity and local acquisition in this region.

Speed and safety of mass spectrometry for identification of Burkholderia pseudomallei directly from spiked blood cultures.

Burkholderia pseudomallei is a bipolar Gram-negative bacillus and the causative agent of melioidosis; an infectious disease which commonly presents with bacteraemia. Data regarding direct from blood culture identification of B. pseudomallei using the Vitek mass spectrometer (MS) are limited. The authors aim to assess the safety and sensitivity of the Vitek MS for identification of B. pseudomallei from spiked positive blood culture samples. Safety was assessed by determining the ability of the standard MS α-cyano-4-hydroxycinnamic acid (CHCA) matrix solution to inactivate B. pseudomallei. Organism identification using the manufacturer's blood culture extraction method was compared to an in-house technique. Additionally, identification following abbreviated agar incubation of blood culture broth was performed. All 70 MS target spots were inactivated by the matrix solution. The manufacturer's blood culture extraction method identified 0/26 (0%) B. pseudomallei samples. An in-house method using the spun deposit from blood culture broth samples identified 38/38 (100%) B. pseudomallei samples. MS analysis of a blood culture broth drop on Chocolate agar following a 6 h incubation identified 30/32 (94%) samples. Decreased time to diagnosis of melioidosis bacteraemia is likely to improve patient outcomes. This study adds to the literature with regards to the utility of MALDI-TOF MS identification of B. pseudomallei both directly from positive blood culture broth and a subsequent 6 h plate incubation. The use of a standard matrix solution inactivates the organism, and use of the spun deposit from a positive blood culture broth is most effective for early identification of B. pseudomallei.

Comparative evaluation of Panther Fusion and real-time PCR for detection of Burkholderia pseudomallei in spiked human blood.

Introduction. Melioidosis is an infection that most commonly presents with bacteraemia. Culture-based laboratory methods can result in a significant delay to organism identification. Molecular diagnostic techniques have a high sensitivity and rapid time to diagnosis. A decreased time to diagnosis is likely to improve patient outcomes. Aim. To compare the Panther Fusion automated molecular instrument to an in-house method for the detection of Burkholderia pseudomallei directly from spiked human whole-blood samples. Results. The in-house method detected 11/12 (92 %) samples with a B. pseudomallei concentration of 2.5-4.5×102 c.f.u. ml-1. The Panther was less reliable, detecting only 8/14 (75 %) samples with a similar bacterial concentration. The Panther was able to detect 12/12 (100 %) spiked blood culture-positive samples. Conclusion. The direct detection of B. pseudomallei from patient blood on presentation to a healthcare facility will significantly decrease time to diagnosis. We describe an in-house real-time PCR method with the lowest reported limit of detection to date. Due to lower sensitivity, the Panther Fusion would be best used as a diagnostic method directly from a positive blood culture.

The epidemiology of melioidosis in Townsville, Australia.

BACKGROUND: Melioidosis in an infection caused by Burkholderia pseudomallei, an organism endemic to tropical and subtropical regions. METHODS: This study describes the epidemiology of melioidosis in Townsville, QLD, Australia, as well as clinical features, risk factors associated with the disease, the burden of infection on the Aboriginal and Torres Strait Islander (ATSI) community and patient outcomes over time. RESULTS: From 1997 to 2020, 128 patients were admitted to Townsville University Hospital. The total annual incidence of infection was 3.2 cases per 100 000 compared with 15.3 per 100 000 in the ATSI population. The majority of cases (n=82 [64%]) were male. Alcohol excess (55%) and diabetes mellitus (48%) were the most common risk factors. Bacteraemia occurred in 87 (70%) patients and pneumonia was the most common focus of infection in 84 (69%). The case fatality rate was 23%, with no difference for the ATSI population (6/32 [19%]). The presence of malignancy was the risk factor most associated with mortality (relative risk 2.7 [95% confidence interval 1.4-5.1], p=0.005). CONCLUSIONS: The ATSI community was overrepresented in this study, however, there was no significant difference in adverse outcomes. The case fatality rate was higher than in other regions in Australia. This discrepancy may relate in part to the different risk groups seen in these settings coupled with potential organism variability.

Clinical Burkholderia pseudomallei isolates from north Queensland carry diverse bimABm genes that are associated with central nervous system disease and are phylogenomically distinct from other Australian strains.

BACKGROUND: Burkholderia pseudomallei is an environmental gram-negative bacterium that causes the disease melioidosis and is endemic in many countries of the Asia-Pacific region. In Australia, the mortality rate remains high at approximately 10%, despite curative antibiotic treatment being available. The bacterium is almost exclusively found in the endemic region, which spans the tropical Northern Territory and North Queensland, with clusters occasionally present in more temperate climates. Despite being endemic to North Queensland, these infections remain understudied compared to those of the Northern Territory. METHODOLOGY/PRINCIPAL FINDINGS: This study aimed to assess the prevalence of central nervous system (CNS) disease associated variant bimABm, identify circulating antimicrobial resistance mutations and genetically distinct strains from Queensland, via comparative genomics. From 76 clinical isolates, we identified the bimABm variant in 20 (26.3%) isolates and in 9 (45%) of the isolates with documented CNS infection (n = 18). Explorative analysis suggests a significant association between isolates carrying the bimABm variant and CNS disease (OR 2.8, 95% CI 1.3-6.0, P = 0.009) compared with isolates carrying the wildtype bimABp. Furthermore, 50% of isolates were identified as novel multi-locus sequence types, while the bimABm variant was more commonly identified in isolates with novel sequence types, compared to those with previously described. Additionally, mutations associated with acquired antimicrobial resistance were only identified in 14.5% of all genomes. CONCLUSIONS/SIGNIFICANCE: The findings of this research have provided clinically relevant genomic data of B. pseudomallei in Queensland and suggest that the bimABm variant may enable risk stratification for the development CNS complications and be a potential therapeutic target.