Performance of 16S rRNA Gene Next-Generation Sequencing and the Culture Method in the Detection of Bacteria in Clinical Specimens.

Effective treatment of infectious diseases requires prompt and accurate bacterial identification and tailored antimicrobial treatments. Traditional culture methods are considered the gold standard, but their effectiveness diminishes for fastidious and hard-to-grow microorganisms. In recent years, molecular diagnostic tools such as 16S rRNA gene next-generation sequencing (16S NGS) have gained popularity in the field. We analysed data from samples submitted for 16S NGS between July 2022 and July 2023 at the Department of Advanced Translational Microbiology in Trieste, Italy. The study included samples submitted for both culture-based identification and 16S NGS. Conventional media were used for culture, and bacterial identification was performed using MALDI-TOF mass spectrometry. The V3 region of the 16S rRNA gene was sequenced using the Ion PGM platform. Among the 123 samples submitted, drainage fluids (38%) and blood (23%) were the most common, with requests predominantly from the Infectious Diseases (31.7%) and Orthopedic (21.13%) Units. In samples collected from patients with confirmed infections, 16S NGS demonstrated diagnostic utility in over 60% of cases, either by confirming culture results in 21% or providing enhanced detection in 40% of instances. Among the 71 patients who had received antibiotic therapies before sampling (mean 2.3 prior antibiotic days), pre-sampling antibiotic consumption did not significantly affect the sensitivity of 16S NGS. In routine microbiology laboratories, combining 16S NGS with culture method enhances the sensitivity of microbiological diagnostics, even when sampling is conducted during antibiotic therapy.

HAP-FAST: a feasibility study incorporating qualitative, mechanistic and costing sub-studies alongside a randomised pilot trial comparing chest x-ray to low-dose CT scan and empirical antibiotics to antibiotics guided by the BIOFIRE® FILM ARRAY® pneumonia plus panel in adults with suspected non-ventilator-associated hospital-cquired pneumonia.

INTRODUCTION: Non-ventilator-associated hospital-acquired pneumonia (nv-HAP) is the most common healthcare-associated infection (HCAI), is associated with high mortality and morbidity and places a major burden on healthcare systems. Diagnosis currently relies on chest x-rays to confirm pneumonia and sputum cultures to determine the microbiological cause. This approach leads to over-diagnosis of pneumonia, rarely identifies a causative pathogen and perpetuates unnecessary and imprecise antibiotic use. The HAP-FAST study aims to evaluate the feasibility of a randomised trial to evaluate the clinical impact of low-dose, non-contrast-enhanced thoracic CT scans and rapid molecular sputum analysis using the BIOFIRE® FILMARRAY® pneumonia plus panel (FAPP) for patients suspected with nv-HAP. METHODS AND ANALYSIS: The HAP-FAST feasibility study consists of a pilot randomised trial, a qualitative study, a costing analysis and exploratory analyses of clinical samples to investigate the immune-pathophysiology of HAP. Participants are identified and recruited from four acute hospitals in the Northwest of the UK. Using a Research Without Prior Consent model, the pilot trial will recruit 220 adult participants, with or without mental capacity, and with suspected HAP. HAP-FAST is a non-blinded, sequential, multiple assignment, randomised trial with two possible stages of randomisation: first, chest x-ray (CXR) or CT; second, if treated as nv-HAP, FAPP or standard microbiological processing alone (no FAPP). Pathogen-specific antibiotic guidance will be provided for FAPP results. Randomisation uses a web-based platform and followed up for 90 days. The feasibility of a future trial will be determined by assessing trial processes, outcome measures and patient and staff experiences. ETHICS AND DISSEMINATION: This study has undergone combined review by the UK NHS Research Ethics Committee and Health Research Authority. Results will be disseminated via peer-reviewed journals, via the funders' website and through a range of media to engage the public. TRIAL REGISTRATION NUMBER: NCT05483309.

Using cerebrospinal fluid nanopore sequencing assay to diagnose tuberculous meningitis: a retrospective cohort study in China.

OBJECTIVE: This study aimed to evaluate the efficiency of nanopore sequencing for the early diagnosis of tuberculous meningitis (TBM) using cerebrospinal fluid and compared it with acid-fast bacilli (AFB) smear, mycobacterial growth indicator tube culture and Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF). DESIGN: Single-centre retrospective study. SETTING: The Tuberculosis Diagnosis and Treatment Center of Zhejiang Chinese and Western Medicine Integrated Hospital. PARTICIPANTS: We enrolled 64 adult patients with presumptive TBM admitted to our hospital from August 2021 to August 2023. METHODS: We calculated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of AFB smear, culture, Xpert MTB/RIF and nanopore sequencing to evaluate their diagnostic efficacy compared with a composite reference standard for TBM. RESULTS: Among these 64 patients, all tested negative for TBM by AFB smear. The sensitivity, specificity, PPV and NPV were 11.11%, 100%, 100% and 32.2% for culture, 13.33%, 100%, 100% and 2.76% for Xpert MTB/RIF, and 77.78%, 100%, 100% and 65.52% for nanopore sequencing, respectively. CONCLUSION: The diagnostic accuracy of the nanopore sequencing test was significantly higher than that of conventional testing methods used to detect TBM.

Standardised protocol for a prospective international multicentre clinical-based evaluation of point-of-care tests for the screening of genital and extragenital chlamydial and gonococcal infections in men who have sex with men and for the screening of genital chlamydial, gonococcal and Trichomonas vaginalis infections in at risk women.

INTRODUCTION: In 2016, WHO estimated there were roughly 374 million new infections among adults of the following four curable sexually transmitted infections (STIs): chlamydia (caused by Chlamydia trachomatis (CT)), gonorrhoea (Neisseria gonorrhoeae (NG)), syphilis (Treponema pallidum) and trichomoniasis (Trichomonas vaginalis (TV)). Accurate point-of-care tests (POCTs) for screening of genital and extragenital CT, NG and TV infections are of great value and have been developed during recent decade. Several tests are commercially available and have shown encouraging performance compared with 'gold-standard' reference tests in laboratory-based studies. However, there is limited data on their clinical performance, including at the POC. Key populations, such as men who have sex with men (MSM), are at higher risk of these STIs at genital and extragenital sites and these STIs are often asymptomatic, especially in extragenital sites and in women. We will conduct a clinical-based evaluation to assess the performance characteristics and acceptability to end-users of molecular-based diagnostic technology for POC/near patient use of the Xpert CT/NG (Cepheid, Sunnyvale, California, USA) test for screening of genital, anorectal and pharyngeal CT and NG infections in MSM and the Xpert CT/NG and Xpert TV (Cepheid, Sunnyvale, California, USA) for screening of genital CT, NG and TV among women at risk for these STIs compared with gold-standard reference nucleic acid amplification tests. This master protocol outlines the overall research approach that will be used in seven countries. METHOD AND ANALYSES: Consecutive MSM and women at risk presenting at the clinical sites in high, and low- and middle-income countries will be enrolled. The POCTs to be evaluated are Xpert CT/NG and Xpert TV. All procedures will be carried out by trained healthcare staff and tests performed in strict accordance with the manufacturer's instructions. The sensitivity, specificity, positive and negative predictive values for each POCT will be calculated. The study is ongoing with recruitment expected to be completed in all countries by mid-2022 to late-2022. ETHICS AND DISSEMINATION: Prior to enrolment, this core protocol was independently peer-reviewed and approved by the research project review panel (RP2) of the WHO Department of Sexual and Reproductive Health and Research and by the WHO Ethics Review Committee (ERC). The core protocol has been slightly adapted accordingly to individual countries and adaptations approved by both RP2 and ERC, as well as all relevant institutional review boards at each participating site. Results will be disseminated through peer-reviewed journals and presented at relevant national/international conferences.

Bacterial growth in patients with low back pain and Modic changes: protocol of a multicentre, case-control biopsy study.

INTRODUCTION: Bacterial infection and Modic changes (MCs) as causes of low back pain (LBP) are debated. Results diverged between two randomised controlled trials examining the effect of amoxicillin with and without clavulanic acid versus placebo on patients with chronic LBP (cLBP) and MCs. Previous biopsy studies have been criticised with regard to methods, few patients and controls, and insufficient measures to minimise perioperative contamination. In this study, we minimise contamination risk, include a control group and optimise statistical power. The main aim is to compare bacterial growth between patients with and without MCs. METHODS AND ANALYSIS: This multicentre, case-control study examines disc and vertebral body biopsies of patients with cLBP. Cases have MCs at the level of tissue sampling, controls do not. Previously operated patients are included as a subgroup. Tissue is sampled before antibiotic prophylaxis with separate instruments. We will apply microbiological methods and histology on biopsies, and predefine criteria for significant bacterial growth, possible contamination and no growth. Microbiologists, surgeons and pathologist are blinded to allocation of case or control. Primary analysis assesses significant growth in MC1 versus controls and MC2 versus controls separately. Bacterial disc growth in previously operated patients, patients with large MCs and growth from the vertebral body in the fusion group are all considered exploratory analyses. ETHICS AND DISSEMINATION: The Regional Committees for Medical and Health Research Ethics in Norway (REC South East, reference number 2015/697) has approved the study. Study participation requires written informed consent. The study is registered at ClinicalTrials.gov (NCT03406624). Results will be disseminated in peer-reviewed journals, scientific conferences and patient fora. TRIAL REGISTRATION NUMBER: NCT03406624.

Appropriate use of blood cultures in the emergency department through machine learning (ABC): study protocol for a randomised controlled non-inferiority trial.

INTRODUCTION: The liberal use of blood cultures in emergency departments (EDs) leads to low yields and high numbers of false-positive results. False-positive, contaminated cultures are associated with prolonged hospital stays, increased antibiotic usage and even higher hospital mortality rates. This trial aims to investigate whether a recently developed and validated machine learning model for predicting blood culture outcomes can safely and effectively guide clinicians in withholding unnecessary blood culture analysis. METHODS AND ANALYSIS: A randomised controlled, non-inferiority trial comparing current practice with a machine learning-guided approach. The primary objective is to determine whether the machine learning based approach is non-inferior to standard practice based on 30-day mortality. Secondary outcomes include hospital length-of stay and hospital admission rates. Other outcomes include model performance and antibiotic usage. Participants will be recruited in the EDs of multiple hospitals in the Netherlands. A total of 7584 participants will be included. ETHICS AND DISSEMINATION: Possible participants will receive verbal information and a paper information brochure regarding the trial. They will be given at least 1 hour consideration time before providing informed consent. Research results will be published in peer-reviewed journals. This study has been approved by the Amsterdam University Medical Centers' local medical ethics review committee (No 22.0567). The study will be conducted in concordance with the principles of the Declaration of Helsinki and in accordance with the Medical Research Involving Human Subjects Act, General Data Privacy Regulation and Medical Device Regulation. TRIAL REGISTRATION NUMBER: NCT06163781.

Implementation of an antibiotic resistance surveillance tool in Madagascar, the TSARA project: a prospective, observational, multicentre, hospital-based study protocol.

INTRODUCTION: Antimicrobial resistance (AMR) has become a significant public health threat. Without any interventions, it has been modelled that AMR will account for an estimated 10 million deaths annually by 2050, this mainly affects low/middle-income countries. AMR has a systemic negative perspective affecting the overall healthcare system down to the patient's personal outcome. In response to this issue, the WHO urged countries to provide antimicrobial stewardship programmes (ASPs). ASPs in hospitals are a vital component of national action plans for AMR, and have been shown to significantly reduce AMR, in particular in low-income countries such as Madagascar.As part of an ASP, AMR surveillance provides essential information needed to guide medical practice. We developed an AMR surveillance tool-Technique de Surveillance Actualisée de la Résistance aux Antimicrobiens (TSARA)-with the support of the Mérieux Foundation. TSARA combines bacteriological and clinical information to provide a better understanding of the scope and the effects of AMR in Madagascar, where no such surveillance tool exists. METHODS AND ANALYSIS: A prospective, observational, hospital-based study was carried out for data collection using a standardised data collection tool, called TSARA deployed in 2023 in 10 hospitals in Madagascar participating in the national Malagasy laboratory network (Réseau des Laboratoires à Madagascar (RESAMAD)). Any hospitalised patient where the clinician decided to take a bacterial sample is included. As a prospective study, individual isolate-level data and antimicrobial susceptibility information on pathogens were collected routinely from the bacteriology laboratory and compiled with clinical information retrieved from face-to-face interviews with the patient and completed using medical records where necessary. Analysis of the local ecology, resistance rates and antibiotic prescription patterns were collected. ETHICS AND DISSEMINATION: This protocol obtained ethical approval from the Malagasy Ethical Committee n°07-MSANP/SG/AGMED/CNPV/CERBM on 24 January 2023. Findings generated were shared with national health stakeholders, microbiologists, members of the RESAMAD network and the Malagasy academic society of infectious diseases.

Barriers and enablers to blood culture sampling in Indonesia, Thailand and Viet Nam: a Theoretical Domains Framework-based survey.

OBJECTIVE: Blood culture (BC) sampling is recommended for all suspected sepsis patients prior to antibiotic administration. We examine barriers and enablers to BC sampling in three Southeast Asian countries. DESIGN: A Theoretical Domains Framework (TDF)-based survey, comprising a case scenario of a patient presenting with community-acquired sepsis and all 14 TDF domains of barriers/enablers to BC sampling. SETTING: Hospitals in Indonesia, Thailand and Viet Nam, December 2021 to 30 April 2022. PARTICIPANTS: 1070 medical doctors and 238 final-year medical students were participated in this study. Half of the respondents were women (n=680, 52%) and most worked in governmental hospitals (n=980, 75.4%). OUTCOME MEASURES: Barriers and enablers to BC sampling. RESULTS: The proportion of respondents who answered that they would definitely take BC in the case scenario was highest at 89.8% (273/304) in Thailand, followed by 50.5% (252/499) in Viet Nam and 31.3% (157/501) in Indonesia (p<0.001). Barriers/enablers in nine TDF domains were considered key in influencing BC sampling, including 'priority of BC (TDF-goals)', 'perception about their role to order or initiate an order for BC (TDF-social professional role and identity)', 'perception that BC is helpful (TDF-beliefs about consequences)', 'intention to follow guidelines (TDF-intention)', 'awareness of guidelines (TDF-knowledge)', 'norms of BC sampling (TDF-social influence)', 'consequences that discourage BC sampling (TDF-reinforcement)', 'perceived cost-effectiveness of BC (TDF-environmental context and resources)' and 'regulation on cost reimbursement (TDF-behavioural regulation)'. There was substantial heterogeneity between the countries. In most domains, the lower (higher) proportion of Thai respondents experienced the barriers (enablers) compared with that of Indonesian and Vietnamese respondents. A range of suggested intervention types and policy options was identified. CONCLUSIONS: Barriers and enablers to BC sampling are varied and heterogenous. Cost-related barriers are more common in more resource-limited countries, while many barriers are not directly related to cost. Context-specific multifaceted interventions at both hospital and policy levels are required to improve diagnostic stewardship practices.

Enhanced active case finding of drug-resistant tuberculosis in Namibia: a protocol for the hotspots, hospitals, and households (H3TB) study.

INTRODUCTION: Namibia is a high tuberculosis (TB)-burden country with an estimated incidence of 460/100 000 (around 12 000 cases) per year. Approximately 4.5% of new cases and 7.9% of previously treated TB cases are multidrug resistant (MDR) and 47% of patients with MDR-TB are HIV coinfected. Published data suggest a clustering of MDR-TB transmission in specific areas. Identifying transmission clusters is key to implementing high-yield and cost-effective interventions. This includes knowing the yield of finding TB cases in high-transmission zones (eg, community hotspots, hospitals or households) to deliver community-based interventions. We aim to identify such transmission zones for enhanced case finding and evaluate the effectiveness of this approach. METHODS AND ANALYSIS: H3TB is an observational cross-sectional study evaluating MDR-TB active case finding strategies. Sputum samples from MDR-TB cases in three regions of Namibia will be evaluated by whole genome sequencing (WGS) in addition to routine sputum investigations (Xpert MTB/RIF, culture and drug susceptibility testing). We will collect information on household contacts, use of community spaces and geographical map intersections between participants, synthesising these data to identify transmission hotspots. We will look at the feasibility, acceptability, yield and cost of case finding strategies in these hotspots, and in households of patients with MDR-TB and visitors of hospitalised patients with MDR-TB. A compartmental transmission dynamic model will be constructed to evaluate the impact and cost-effectiveness of the strategies if scaled. ETHICS AND DISSEMINATION: Ethics approval was obtained. Participants will give informed consent. H3TB will capitalise on a partnership with the Ministry of Health and Social Services to follow up individuals diagnosed with MDR-TB and integrate WGS data with innovative contact network mapping, to allow enhanced case finding. Study data will contribute towards a systems approach to TB control. Equally important, it will serve as a role model for similar studies in other high-incidence settings.

ChatGPT Performance in Diagnostic Clinical Microbiology Laboratory-Oriented Case Scenarios.

BACKGROUND: Artificial intelligence (AI)-based tools can reshape healthcare practice. This includes ChatGPT which is considered among the most popular AI-based conversational models. Nevertheless, the performance of different versions of ChatGPT needs further evaluation in different settings to assess its reliability and credibility in various healthcare-related tasks. Therefore, the current study aimed to assess the performance of the freely available ChatGPT-3.5 and the paid version ChatGPT-4 in 10 different diagnostic clinical microbiology case scenarios. METHODS: The current study followed the METRICS (Model, Evaluation, Timing/Transparency, Range/Randomization, Individual factors, Count, Specificity of the prompts/language) checklist for standardization of the design and reporting of AI-based studies in healthcare. The models tested on December 3, 2023 included ChatGPT-3.5 and ChatGPT-4 and the evaluation of the ChatGPT-generated content was based on the CLEAR tool (Completeness, Lack of false information, Evidence support, Appropriateness, and Relevance) assessed on a 5-point Likert scale with a range of the CLEAR scores of 1-5. ChatGPT output was evaluated by two raters independently and the inter-rater agreement was based on the Cohen's κ statistic. Ten diagnostic clinical microbiology laboratory case scenarios were created in the English language by three microbiologists at diverse levels of expertise following an internal discussion of common cases observed in Jordan. The range of topics included bacteriology, mycology, parasitology, and virology cases. Specific prompts were tailored based on the CLEAR tool and a new session was selected following prompting each case scenario. RESULTS: The Cohen's κ values for the five CLEAR items were 0.351-0.737 for ChatGPT-3.5 and 0.294-0.701 for ChatGPT-4 indicating fair to good agreement and suitability for analysis. Based on the average CLEAR scores, ChatGPT-4 outperformed ChatGPT-3.5 (mean: 2.64±1.06 vs. 3.21±1.05, P=.012, t-test). The performance of each model varied based on the CLEAR items, with the lowest performance for the "Relevance" item (2.15±0.71 for ChatGPT-3.5 and 2.65±1.16 for ChatGPT-4). A statistically significant difference upon assessing the performance per each CLEAR item was only seen in ChatGPT-4 with the best performance in "Completeness", "Lack of false information", and "Evidence support" (P=0.043). The lowest level of performance for both models was observed with antimicrobial susceptibility testing (AST) queries while the highest level of performance was seen in bacterial and mycologic identification. CONCLUSIONS: Assessment of ChatGPT performance across different diagnostic clinical microbiology case scenarios showed that ChatGPT-4 outperformed ChatGPT-3.5. The performance of ChatGPT demonstrated noticeable variability depending on the specific topic evaluated. A primary shortcoming of both ChatGPT models was the tendency to generate irrelevant content lacking the needed focus. Although the overall ChatGPT performance in these diagnostic microbiology case scenarios might be described as "above average" at best, there remains a significant potential for improvement, considering the identified limitations and unsatisfactory results in a few cases.

Genital tract infections, the vaginal microbiome and gestational age at birth among pregnant women in South Africa: a cohort study protocol.

INTRODUCTION: Preterm birth complications are the most common cause of death in children under 5 years. The presence of multiple microorganisms and genital tract inflammation could be the common mechanism driving early onset of labour. South Africa has high levels of preterm birth, genital tract infections and HIV infection among pregnant women. We plan to investigate associations between the presence of multiple lower genital tract microorganisms in pregnancy and gestational age at birth. METHODS AND ANALYSIS: This cohort study enrols around 600 pregnant women at one public healthcare facility in East London, South Africa. Eligible women are ≥18 years and at <27 weeks of gestation, confirmed by ultrasound. At enrolment and 30-34 weeks of pregnancy, participants receive on-site tests for Chlamydia trachomatis and Neisseria gonorrhoeae, with treatment if test results are positive. At these visits, additional vaginal specimens are taken for: PCR detection and quantification of Trichomonas vaginalis, Candida spp., Mycoplasma genitalium, M. hominis, Ureaplasma urealyticum and U. parvum; microscopy and Nugent scoring; and for 16S ribosomal RNA gene sequencing and quantification. Pregnancy outcomes are collected from a postnatal visit and birth registers. The primary outcome is gestational age at birth. Statistical analyses will explore associations between specific microorganisms and gestational age at birth. To explore the association with the quantity of microorganisms, we will construct an index of microorganism load and use mixed-effects regression models and classification and regression tree analysis to examine which combinations of microorganisms contribute to earlier gestational age at birth. ETHICS AND DISSEMINATION: This protocol has approvals from the University of Cape Town Research Ethics Committee and the Canton of Bern Ethics Committee. Results from this study will be uploaded to preprint servers, submitted to open access peer-reviewed journals and presented at regional and international conferences. TRIAL REGISTRATION NUMBER: NCT06131749; Pre-results.

Country adoption of WHO 2019 guidance on HIV testing strategies and algorithms: a policy review across the WHO African region.

OBJECTIVES: In 2019, the WHO released guidelines on HIV testing service (HTS). We aim to assess the adoption of six of these recommendations on HIV testing strategies among African countries. DESIGN: Policy review. SETTING: 47 countries within the WHO African region. PARTICIPANTS: National HTS policies from the WHO African region as of December 2021. PRIMARY AND SECONDARY OUTCOME MEASURES: Uptake of WHO recommendations across national HTS policies including the standard three-test strategy; discontinuation of a tiebreaker test to rule in HIV infection; discontinuation of western blotting (WB) for HIV diagnosis; retesting prior to antiretroviral treatment (ART) initiation and the use of dual HIV/syphilis rapid diagnostic tests (RDTs) in antenatal care. Country policy adoption was assessed on a continuum, based on varying levels of complete adoption. RESULTS: National policies were reviewed for 96% (n=45/47) of countries in the WHO African region, 38% (n=18) were published before 2019 and 60% (n=28) adopted WHO guidance. Among countries that had not fully adopted WHO guidance, not yet adopting a three-test strategy was the most common reason for misalignment (45%, 21/47); of which 31% and 22% were in low-prevalence (<5%) and high-prevalence (≥5%) countries, respectively. Ten policies (21%) recommended the use of WB and 49% (n=23) recommended retesting before ART initiation. Dual HIV/syphilis RDTs were recommended in 45% (n=21/47) of policies. CONCLUSIONS: Many countries in the African region have adopted WHO-recommended HIV testing strategies; however, efforts are still needed to fully adopt WHO guidance. Countries should accelerate their efforts to adopt and implement a three-test strategy, retesting prior to ART initiation and the use of dual HIV/syphilis RDTs.

WHY STOP? A prospective observational vignette-based study to determine the cognitive-behavioural effects of rapid diagnostic PCR-based point-of-care test results on antibiotic cessation in ICU infections.

OBJECTIVES: Point-of-care tests (POCTs) for infection offer accurate rapid diagnostics but do not consistently improve antibiotic stewardship (ASP) of suspected ventilator-associated pneumonia. We aimed to measure the effect of a negative PCR-POCT result on intensive care unit (ICU) clinicians' antibiotic decisions and the additional effects of patient trajectory and cognitive-behavioural factors (clinician intuition, dis/interest in POCT, risk averseness). DESIGN: Observational cohort simulation study. SETTING: ICU. PARTICIPANTS: 70 ICU consultants/trainees working in UK-based teaching hospitals. METHODS: Clinicians saw four case vignettes describing patients who had completed a course of antibiotics for respiratory infection. Vignettes comprised clinical and biological data (ie, white cell count, C reactive protein), varied to create four trajectories: clinico-biological improvement (the 'improvement' case), clinico-biological worsening ('worsening'), clinical improvement/biological worsening ('discordant clin better'), clinical worsening/biological improvement ('discordant clin worse'). Based on this, clinicians made an initial antibiotics decision (stop/continue) and rated confidence (6-point Likert scale). A PCR-based POCT was then offered, which clinicians could accept or decline. All clinicians (including those who declined) were shown the result, which was negative. Clinicians updated their antibiotics decision and confidence. MEASURES: Antibiotics decisions and confidence were compared pre-POCT versus post-POCT, per vignette. RESULTS: A negative POCT result increased the proportion of stop decisions (54% pre-POCT vs 70% post-POCT, χ2(1)=25.82, p<0.001, w=0.32) in all vignettes except improvement (already high), most notably in discordant clin worse (49% pre-POCT vs 74% post-POCT). In a linear regression, factors that significantly reduced clinicians' inclination to stop antibiotics were a worsening trajectory (b=-0.73 (-1.33, -0.14), p=0.015), initial confidence in continuing (b=0.66 (0.56, 0.76), p<0.001) and involuntary receipt of POCT results (clinicians who accepted the POCT were more inclined to stop than clinicians who declined it, b=1.30 (0.58, 2.02), p<0.001). Clinician risk averseness was not found to influence antibiotic decisions (b=-0.01 (-0.12, 0.10), p=0.872). CONCLUSIONS: A negative PCR-POCT result can encourage antibiotic cessation in ICU, notably in cases of clinical worsening (where the inclination might otherwise be to continue). This effect may be reduced by high clinician confidence to continue and/or disinterest in POCT, perhaps due to low trust/perceived utility. Such cognitive-behavioural and trajectorial factors warrant greater consideration in future ASP study design.

Evolution of Diagnostic and Forensic Microbiology in the Era of Artificial Intelligence.

Diagnostic microbiology plays a vital role in managing infectious diseases, combating antimicrobial resistance, and containment of outbreaks. During the fourth industrial revolution, when artificial intelligence (AI) became an essential part of our day-to-day lives, its integration into healthcare would further revolutionize our knowledge and potential. Although in the budding stage, AI with machine learning is being increasingly utilized in various aspects of diagnostic microbiology. It can handle large datasets that are difficult to analyze manually. Researchers have developed and demonstrated several machine-learning algorithms for interpreting bacterial cultures, conducting image analysis for microbial detection, and predicting antimicrobial susceptibility patterns. Thus, AI may most likely be the ultimate solution to the ever-increasing demand for improved results with shorter turnaround times. AI can also assist forensic microbiologists in crime scene investigations, as it can guide individual identification, cause and time since death, and manner of death. This review summarizes the application of AI in diagnostic microbiology for performing diverse sets of microbial investigations and is an essential aid in forensic microbiology.

Diagnostic validity of MRI for central nervous system tuberculosis: protocol for a systematic review and meta-analysis.

INTRODUCTION: Central nervous system tuberculosis (CNSTB) is a severe condition, sometimes associated with a poor prognosis. Early diagnosis of CNSTB remains challenging, considering that conventional methods lack sensitivity or might lead to certain side effects. Herein, we presented a protocol for a systematic review and meta-analysis to assess the diagnostic efficacy of MRI for CNSTB. METHODS AND ANALYSIS: SinoMed, Wanfang database, China National Knowledge Infrastructure, Embase, the Cochrane Library and PubMed will be searched to identify studies reporting on the use of MRI in the diagnosis of CNSTB from database inception to December 2023. The following keywords will be applied: 'Intracranial tuberculosis', 'Cerebral tuberculosis', 'Central nervous system tuberculosis', 'Spinal tuberculous arachnoiditis' and 'Magnetic Resonance Imaging'. Studies that evaluate the diagnostic accuracy of MRI for the diagnosis of CNSTB and report clear reference criteria will be included. Studies from which full true positive, false positive, false negative and true negative values cannot be extracted, those published in languages other than English or Chinese, abstracts not reporting the full text, and case reports will be excluded. Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) will be used to evaluate the methodological quality of each included study. Stata V.15.0 and RevMan V.5.3 will be used to perform a meta-analysis and generate forest plots and summary receiver operating characteristic curves. In case of significant heterogeneity between studies, possible sources of heterogeneity will be explored through subgroup and meta-regression analyses. ETHICS AND DISSEMINATION: This research is based on public databases and does not require ethical approval. Results will be submitted for publication in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42023415690.

Diagnostic utility of haematological parameters in predicting the severity of HIV infection in southwestern Ethiopia: a comparative cross-sectional study.

OBJECTIVES: This study aimed to evaluate the diagnostic utility of haematological parameters as a predictive marker of the severity of HIV infection in southwestern Ethiopia. DESIGN: Comparative cross-sectional study. SETTING: This study was conducted in southwestern Ethiopia. PARTICIPANTS: Venous blood samples were collected from 344 participants (172 HIV, 172 healthy controls (HC)) and haematological parameters were determined using the automated haematology analyser. The diagnostic utility of haematological parameters was determined by a receiver operating curve analysis. Data were analysed using SPSS V.21 and the p value was set at less than 0.05 for the statistical significance. RESULTS: In this study, red cell count (RCC) distinguishes HIV-infected patients from HC at a threshold value of 4.05×109/L with sensitivity, specificity and an area under the curves (AUC) of 73.8%, 78.5% and 0.87, respectively. At a cut-off value of 4.25×109/L, RCC significantly distinguishes non-severe HIV-infected patients from HC with a sensitivity of 72.7%, specificity of 81.7% and an AUC of 0.86. Haemoglobin (Hgb) significantly differentiates severe HIV-infected patients from HC with sensitivity, specificity and an AUC of 95.9%, 86.7% and 0.96, respectively. Platelet count (PLT) significantly discriminates HC from non-severe and severe HIV-infected patients with an AUC of 0.74 and 0.963, respectively. CONCLUSION: RCC, PLT and Hgb demonstrated better diagnostic performance in predicting the severity of HIV infection and have been identified as the best haematological markers in predicting the presence and severity of HIV infection. Thus, the haematological profiles (RCC, PLT and Hgb) should be used as an alternative marker to predict the severity of HIV infection and may provide supportive information for evidence-based interventions and early diagnosis of infections.

Randomised, open-label, non-inferiority clinical trial on the efficacy and safety of a 7-day vs 14-day course of antibiotic treatment for uncomplicated enterococcal bacteraemia: the INTENSE trial protocol.

INTRODUCTION: Enterococcus spp is responsible for 8%-15% of total bacteraemias with an associated global mortality around 23%-30%. Regarding the clinical management of enterococcal bacteraemia, the evidence on the duration of antibiotic treatment is scarce and the studies do not discriminate between complicated and uncomplicated bacteraemia. METHODS: The INTENSE study is a multicentre, open-label, randomised, pragmatic, phase-IV clinical trial to demonstrate the non-inferiority of a 7-day vs 14-day course for the treatment of uncomplicated enterococcal bacteraemia and incorporating the early switching to oral antibiotics when feasible. The primary efficacy endpoint is the clinical cure at day 30±2 after the end of the treatment. Secondary endpoints will include the rate of relapse or infective endocarditis, length of stay, duration of intravenous therapy, Clostridioides difficile infection and the evaluation of the safety of both treatment arms through the recording and analysis of adverse events. For a 6% non-inferiority margin and considering a 5% withdrawal rate, 284 patients will be included. ANALYSIS: The difference in proportions with one-sided 95% CIs will be calculated for the clinical cure rate using the control group as reference. For secondary categorical endpoints, a similar analysis will be performed and Mann-Whitney U-test will be used to compare median values of quantitative variables. A superiority analysis applying the response adjusted for days of antibiotic risk will be performed if there were incidents in recruitment; will allow obtaining results with 194 patients recruited. ETHICS AND DISSEMINATION: The study has obtained the authorisation from the Spanish Regulatory Authority, the approval of the ethics committee and the agreement of the directors of each centre. Data will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05394298.

Extra-urogenital infection by Mycoplasma hominis in transplant patients: two case reports and literature review.

BACKGROUND: Mycoplasma hominis is a facultative anaerobic bacterium commonly present in the urogenital tract. In recent years, M. hominis has increasingly been associated with extra-urogenital tract infections, particularly in immunosuppressed patients. Detecting M. hominis in a diagnostic laboratory can be challenging due to its slow growth rate, absence of a cell wall, and the requirements of specialized media and conditions for optimal growth. Consequently, it is necessary to establish guidelines for the detection of this microorganism and to request the appropriate microbiological work-up of immunosuppressed patients. CASE PRESENTATION: We hereby present two cases of solid organ transplant patients who developed M. hominis infection. Microscopic examination of the bronchial lavage and pleural fluid showed no microorganisms. However, upon inoculating the specimens onto routine microbiology media, the organism was successfully identified and confirmation was performed using 16S rDNA sequencing. Both patients received appropriate treatment resulting in the resolution of M. hominis infection. CONCLUSIONS: The prompt detection of M. hominis in a clinical specimen can have a significant impact on patient care by allowing for early intervention and ultimately resulting in more favorable clinical outcomes, especially in transplant patients.

A Difficult-To-Diagnose Case of American Tegumentary Leishmaniasis.

This case report presents a difficult-to-diagnose case of American tegumentary leishmaniasis (ATL) caused by Leishmania (Viannia) guyanensis in a 24-year-old Hispanic male with a travel history to the Panama jungle, an endemic region for tropical infectious diseases. The patient initially presented with persistent skin lesions that progressed to abscesses with ulceration. Despite negative initial diagnostic tests, including microbiological investigations and histopathological examination, a comprehensive diagnostic workup and subsequent polymerase chain reaction (PCR) confirmed the presence of Leishmania parasites. This case underscores the need to consider tropical infectious diseases despite initial negative tests. Accurate species identification is vital for proper drug treatment, with miltefosine as an emerging option. Early, precise diagnosis and tailored management are essential for successful treatment. This report emphasizes the significance of conducting a comprehensive diagnostic workup, including PCR, in individuals with a history of travel to endemic regions, to accurately diagnose and effectively manage complex infectious diseases.