CRISPR-based electrochemical biosensors: an alternative for point-of-care diagnostics?

The combination of CRISPR technology and electrochemical sensors has sparked a paradigm shift in the landscape of point-of-care (POC) diagnostics. This review explores the dynamic convergence between CRISPR and electrochemical sensing, elucidating their roles in rapid and precise biosensing platforms. CRISPR, renowned for its remarkable precision in genome editing and programmability capability, has found a novel application in conjunction with electrochemical sensors, promising highly sensitive and specific detection of nucleic acids and biomarkers associated with diverse diseases. This article navigates through fundamental principles, research developments, and applications of CRISPR-based electrochemical sensors, highlighting their potential to revolutionize healthcare accessibility and patient outcomes. In addition, some key points and challenges regarding applying CRISPR-powered electrochemical sensors in real POC settings are presented. By discussing recent advancements and challenges in this interdisciplinary field, this review evaluates the potential of these innovative sensors as an alternative for decentralized, rapid, and accurate POC testing, offering some insights into their applications across clinical scenarios and their impact on the future of diagnostics.

Impact of point-of-care gonorrhea and chlamydia testing in the emergency department on reducing overtreatment rates.

BACKGROUND: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections continue to increase in the United States. Advancement in technology with point-of-care (POC) testing can improve the overall treatment of sexually transmitted infections (STI) in the emergency department (ED) by shortening the time to test result and administration of accurate treatment. The purpose of this study was to assess if the POC test reduced the rate of overtreatment for CT and/or NG compared to the standard-of-care (SOC) test. METHODS: This retrospective cohort study included adult patients tested for CT and NG at two urban EDs between August 2020 and October 2022. This cohort excluded hospital admissions, elopement, pregnancy, rectal and oral samples, victims of sexual assault, and diagnoses for which antimicrobial treatment overlapped that of CT/NG. The primary outcome assessed overtreatment, defined as receiving treatment in the ED or a prescription prior to discharge for patients who tested negative for CT and/or NG. Secondary outcomes included undertreatment rates, overtreatment rates in select populations, test turnaround time, and ED length of stay (LOS). RESULTS: Of 327 patients screened, 97 patients were included in the SOC group and 100 in POC. Overtreatment for CT was provided in zero POC patients and 29 (29.9%) SOC patients (p < 0.001). NG was overtreated in 1 (1%) POC and 23 (23.7%) SOC (p < 0.001). POC was associated with undertreatment of CT and/or NG in two patients, compared to four patients tested with SOC. Overall, treatment was deemed inappropriate for 5 (5%) of those tested with POC, compared to 35 (36%) tested with SOC (p < 0.001). There was no difference in ED LOS (2.7 vs 3.01 h, p = 0.41). CONCLUSIONS: POC testing facilitated the return of results prior to patients being discharged from the ED. Compared to standard testing, POC improved appropriateness of CT and NG treatment by reducing the rates of overtreatment.

Fluid Responsiveness and Management in Obstetrics using Point-of-Care Ultrasound.

Fluid management in obstetric care is crucial due to the complex physiological conditions of pregnancy, which complicate clinical manifestations and fluid balance management. This expert review examines the use of point-of-care ultrasound (POCUS) to evaluate and monitor the response to fluid therapy in pregnant patients. Pregnancy induces significant physiological changes, including increased cardiac output and glomerular filtration rate, decreased systemic vascular resistance, and plasma oncotic pressure. Conditions like preeclampsia further complicate fluid management due to decreased intravascular volume and increased capillary permeability. Traditional methods of assessing fluid volume status, such as physical examination and invasive monitoring, are often unreliable or inappropriate. POCUS provides a non-invasive, rapid, and reliable means to assess fluid responsiveness, which is essential in managing fluid therapy in pregnant patients. This review details various POCUS modalities used to measure dynamic changes in fluid status, focusing on the evaluation of the inferior vena cava (IVC), lung ultrasound (Lung US), and the left ventricular outflow tract (LVOT). IVC ultrasound in spontaneously breathing patients determines diameter variability, predicting fluid responsiveness and being feasible even late in pregnancy. Lung ultrasound is critical for detecting early signs of pulmonary edema before clinical symptoms arise and is more accurate than traditional radiography. The LVOT velocity-time integral (VTI) assesses stroke volume response to fluid challenges, providing a quantifiable measure of cardiac function, especially beneficial in critical care settings where rapid and accurate fluid management is essential. The expert review synthesizes current evidence and practice guidelines, suggesting integrating POCUS as a fundamental aspect of fluid management in obstetrics. It calls for ongoing research to enhance techniques and validate their use in broader clinical settings, aiming to improve outcomes for pregnant patients and their babies by preventing complications associated with both under- and over-resuscitation.

Development of two novel on-site detection visualization methods for murine hepatitis virus based on the multienzyme isothermal rapid amplification.

Murine hepatitis virus (MHV) infection is one of the most prevalent types of mice infection in laboratory. MHV could cause death in mice and even interfere with the results in animal experiments. Herein, we developed two isothermal approaches based on the Multienzyme Isothermal Rapid Amplification (MIRA), for rapid detection of MHV in conserved M gene. We designed and screened several pairs of primers and probes and the isothermal fluorescence detector was applied for the exonuclease Ⅲ reverse transcription MIRA (exo-RT-MIRA) assay. To further simplify the workflow, the portable fluorescence visualization instrument, also as a palm-sized handheld system, was used for the naked-eye exo-RT-MIRA assay. The amplification temperature and time were optimized. The assay could be processed well at 42 °C 20 min for the exo-RT-MIRA and the naked-eye exo-RT-MIRA assay. The limit of detection (LoD) of the exo-RT-MIRA assay was 43.4 copies/µL. The LoD of the naked-eye exo-RT-MIRA assay was 68.2 copies/µL. No nonspecific amplifications were observed in the two assays. A total of 107 specimens were examined by qPCR and two assays developed. The experimental results statistical analysis demonstrated that the exo-RT-MIRA assay with the qPCR yielded sufficient agreement with a kappa value of 1.000 (p < 0.0001). The results also exhibited a good agreement (kappa value, 0.961) (p < 0.0001) between the naked-eye exo-RT-MIRA assay and the qPCR assay. In our study, the exo-RT-MIRA assay and the naked-eye exo-RT-MIRA assay presented the possibility of new methods in MHV point-of-testing diagnosis.

Multicenter validation study for automated left ventricular ejection fraction assessment using a handheld ultrasound with artificial intelligence.

We sought to validate the ability of a novel handheld ultrasound device with an artificial intelligence program (AI-POCUS) that automatically assesses left ventricular ejection fraction (LVEF). AI-POCUS was used to prospectively scan 200 patients in two Japanese hospitals. Automatic LVEF by AI-POCUS was compared to the standard biplane disk method using high-end ultrasound machines. After excluding 18 patients due to infeasible images for AI-POCUS, 182 patients (63 ± 15 years old, 21% female) were analyzed. The intraclass correlation coefficient (ICC) between the LVEF by AI-POCUS and the standard methods was good (0.81, p < 0.001) without clinically meaningful systematic bias (mean bias -1.5%, p = 0.008, limits of agreement ± 15.0%). Reduced LVEF < 50% was detected with a sensitivity of 85% (95% confidence interval 76%-91%) and specificity of 81% (71%-89%). Although the correlations between LV volumes by standard-echo and those by AI-POCUS were good (ICC > 0.80), AI-POCUS tended to underestimate LV volumes for larger LV (overall bias 42.1 mL for end-diastolic volume). These trends were mitigated with a newer version of the software tuned using increased data involving larger LVs, showing similar correlations (ICC > 0.85). In this real-world multicenter study, AI-POCUS showed accurate LVEF assessment, but careful attention might be necessary for volume assessment. The newer version, trained with larger and more heterogeneous data, demonstrated improved performance, underscoring the importance of big data accumulation in the field.

The utilisation of emergency point-of-care ultrasound in a tertiary hospital emergency department in East London, South Africa.

Introduction: Emergency departments are the primary entry point for emergencies in the public healthcare system. Resource constraints burden a large proportion of the public hospital emergency departments, which includes limited access to radiological services. Emergency point-of-care ultrasound provides a tool capable of bridging this gap. The Eastern Cape is yet to describe the utilisation of emergency point-of-care ultrasound in any of its emergency departments. Methods: Frere Hospital initiated a clinical audit to assess the utilisation of emergency point-of-care ultrasound in its emergency department in 2022. This study was a retrospective review of the audit between 01 November 2022 until 28 February 2023. Data from the handwritten register regarding patient's presenting complaints and provisional diagnoses was also captured during the study period to draw comparisons between burden of disease and use of emergency point-of-care ultrasound. Results: A total of 9501 patients attended Frere Hospital's emergency department over the study period with 492 emergency point-of-care ultrasounds performed (overall utilisation rate 5.2 %). The five credentialed emergency point-of-care ultrasound providers performed the majority (n = 360, 73.2 %) of the applications, compared to 132 (26.8 %) performed by the seven non-credentialed providers. The extended focused abdominal sonography in trauma (eFAST) was the most frequently performed application (n = 140, 28.5 %). Conclusion: Emergency point-of-care ultrasound is underutilised in Frere Hospital's emergency department. The varied casemix requires upskilling of clinicians in emergency point-of-care ultrasound to suit the burden of disease experienced in the department. Ongoing emergency point-of-care ultrasound training, credentialing and research is important to ensure appropriate and quality emergency point-of-care ultrasound utilisation.

Direct RNA Sequencing of Foot-and-mouth Disease Virus Genome Using a Flongle on MinION.

Foot-and-mouth disease (FMD) is a severe and extremely contagious viral disease of cloven-hoofed domestic and wild animals, which leads to serious economic losses to the livestock industry globally. FMD is caused by the FMD virus (FMDV), a positive-strand RNA virus that belongs to the genus Aphthovirus, within the family Picornaviridae. Early detection and characterization of FMDV strains are key factors to control new outbreaks and prevent the spread of the disease. Here, we describe a direct RNA sequencing method using Oxford Nanopore Technology (ONT) Flongle flow cells on MinION Mk1C (or GridION) to characterize FMDV. This is a rapid, low cost, and easily deployed point of care (POC) method for a near real-time characterization of FMDV in endemic areas or outbreak investigation sites. Key features • Saves ~35 min of the original protocol time by omitting the reverse transcription step and lowers the costs of reagents and consumables. • Replaces the GridION flow cell from the original protocol with the Flongle, which saves ~90% on the flow cell cost. • Combines the NGS benchwork with a modified version of our African swine fever virus (ASFV) fast analysis pipeline to achieve FMDV characterization within minutes. Graphical overview Schematic of direct RNA sequencing of foot-and-mouth disease virus (FMDV) process, which takes ~50 min from extracted RNA to final loading, modified from the ONT SQK-RNA002 protocol (Version: DRS_9080_v2_revO_14Aug2019).

Inferior vena cava ultrasound to predict hypotension after general anesthesia induction: a systematic review and meta-analysis of observational studies.

PURPOSE: Hypotension after induction of general anesthesia is common and is associated with significant adverse events. Identification of patients at high risk can inform the use of preoperative mitigation strategies. We conducted a systematic review and meta-analysis to assess the diagnostic accuracy of the inferior vena cava collapsibility index (IVC-CI) and maximal diameter (dIVCmax) in predicting postinduction hypotension and to identify their predictive performance across different threshold ranges. METHODS: We searched MEDLINE, PubMed®, and Embase from inception to March 2023 for prospective observational studies exploring the performance of IVC-CI and dIVCmax in predicting postinduction hypotension in adults presenting for elective surgery under general anesthesia. We excluded studies reporting on IVC parameters predicting postinduction hypotension in the obstetric patient population or exclusively in patients with obesity. Trials screening and data extraction were conducted independently. We performed meta-analyses to identify the performance of IVC parameters in predicting postinduction hypotension, followed by subgroup analyses that sought the IVC-CI range with the highest hierarchical summary receiver-operating characteristic area under the curve (HSROC-AUC). We used a bivariate random effects model to calculate summary estimates. We evaluated study quality using Newcastle-Ottawa scores and certainty of evidence using the GRADE framework. RESULTS: We included 14 studies involving 1,166 patients. Pooled sensitivity and specificity of the IVC-CI to predict postinduction hypotension was 0.68 (95% confidence interval [CI], 0.55 to 0.79; coverage probability, 0.91) and 0.78 (95% CI, 0.69 to 0.85; coverage probability, 0.9), respectively, with an HSROC-AUC of 0.80 (95% CI, 0.68 to 0.85, high quality of evidence). An IVC-CI threshold range of 40-45% had an HSROC-AUC of 0.86 (95% CI, 0.69 to 0.93, high quality of evidence). CONCLUSIONS: Preoperative IVC-CI is a strong predictor of postinduction hypotension. We recommend that future studies use an IVC-CI threshold of 40-45% (low certainty of evidence). Future studies are needed to establish whether ultrasound-guided preoperative optimization improves outcomes in high-risk patients. STUDY REGISTRATION: PROSPERO ( CRD42022316140 ); first submitted 10 March 2022.

RéSUMé: OBJECTIF: L'hypotension après l'induction de l'anesthésie générale est fréquente et est associée à des effets indésirables importants. L'identification des patient•es à haut risque peut éclairer l'utilisation de stratégies préopératoires d'atténuation. Nous avons réalisé une revue systématique et une méta-analyse pour évaluer la précision diagnostique de l'indice de collapsibilité de la veine cave inférieure (IC-VCI) et du diamètre maximal (dVCImax) pour prédire l'hypotension post-induction et identifier leurs performances prédictives dans différentes plages de seuils. MéTHODE: Nous avons fait des recherches dans les bases de données MEDLINE, PubMed® et Embase de leur création jusqu'en mars 2023 pour en extraire les études observationnelles prospectives explorant les performances de l'IC-VCI et du dVCImax pour la prédiction de l'hypotension post-induction chez des adultes se présentant pour une chirurgie non urgente sous anesthésie générale. Nous avons exclu les études rapportant des paramètres de VCI prédisant l'hypotension post-induction dans la population obstétricale ou exclusivement chez des personnes obèses. Le tri des études et l'extraction des données ont été menés indépendamment. Nous avons réalisé des méta-analyses pour identifier la performance des paramètres de VCI dans la prédiction de l'hypotension post-induction, suivies d'analyses de sous-groupes qui ont recherché la plage d'IC-VCI avec le plus haut niveau de hiérarchie de l'aire sous la courbe de la courbe ROC (HSROC-AUC). Nous avons utilisé un modèle bivarié à effets aléatoires pour calculer des estimations sommaires. Nous avons évalué la qualité des études à l'aide des scores de Newcastle-Ottawa et la certitude des données probantes à l'aide de l'outil GRADE. RéSULTATS: Quatorze études portant sur 1166 patient·es ont été incluses. La sensibilité et la spécificité combinées de l'IC-VCI pour prédire l'hypotension post-induction étaient de 0,68 (intervalle de confiance [IC] à 95 %, 0,55 à 0,79; probabilité de couverture, 0,91) et 0,78 (IC 95 %, 0,69 à 0,85; probabilité de couverture, 0,9), respectivement, avec une HSROC-AUC de 0,80 (IC 95 %, 0,68 à 0,85, données probantes de haute qualité). Une plage de seuils d'IC-VCI de 40 à 45 % avait une HSROC-AUC de 0,86 (IC 95 %, 0,69 à 0,93, haute qualité des données probantes). CONCLUSION: L'IC-VCI préopératoire est un bon prédicteur de l'hypotension post-induction. Nous recommandons que les études futures utilisent un seuil d'IC-VCI de 40 à 45 % (faible certitude des données probantes). De futures études sont nécessaires pour déterminer si l'optimisation préopératoire échoguidée améliore les devenirs chez la patientèle à risque élevé. ENREGISTREMENT DE L'éTUDE: PROSPERO ( CRD42022316140 ); première soumission le 10 mars 2022.

Effect of Departmental and Physician-Selected Interventions on Point-of-Care Ultrasound Documentation Completion.

Background Point-of-care ultrasound (POCUS) has been disruptive to many experienced emergency physicians as it requires competence in a new physical skill, real-time image interpretation, and navigation of novel software for submission to the electronic health record (EHR). Incomplete documentation of a performed POCUS study used for clinical decision-making represents a potential medicolegal liability, may expose the patient to repetitive or potentially unnecessary imaging, and is a missed opportunity for reimbursement. Identifying effective facilitators of ED POCUS documentation completion requires additional investigation. Methods In the first part of this mixed-methods study, eligible attending physicians were stratified into levels of use ("high"/"low"/"never") based on recent POCUS documentation performance. Semi-structured interviews were conducted with high and low utilizers to explore their perceptions of the POCUS submission workflow and their receptivity to various proposed interventions. Qualitative data were analyzed using a thematic analysis that explored perceived usefulness and usability. The second part of the study consisted of two intervention phases. First, physicians achieving minimum POCUS documentation numbers were rewarded with additional shift scheduling flexibility. In the second phase, the intervention that garnered the most interview support, daily documentation reminder emails, was implemented. The primary outcome was the individual POCUS documentation rates calculated as all studies submitted divided by all studies performed (submitted plus unsubmitted) per month. Provider-level monthly data was aggregated into a departmental rate. Results Interviews were conducted with 12 physicians, six from the highest and six from the lowest documentation quartiles. Both groups supported the same two proposed interventions: reminder emails ranked first, then monetary rewards ranked second. High utilizers emphasized the clinical utility of POCUS, whereas low utilizers expressed concerns over "double billing" and exposure to medicolegal liability with uncertain scan interpretations. For low utilizers, a documentation decision could be dependent on the performing resident physician's displayed confidence. Both groups voiced frustration with the need to use a separate program, Qpath (Telexy Healthcare, Inc, Maple Ridge, British Columbia, Canada), for POCUS documentation. During intervention phase one, the aggregate departmental documentation rate increased from 44.6% to 60.1% with the introduction of the schedule request incentive. This improvement was seen across all documentation quartiles. The departmental rate remained stable and did not improve further following the addition of the daily documentation reminder emails in intervention phase two. When reminder emails ceased yet the day-off request incentive continued, the departmental rate did not drop. Conclusions The implementation of a non-financial shift scheduling incentive correlated with the largest increase in departmental POCUS documentation rate. Interviewees incorrectly predicted that email reminders would be the most influential intervention highlighting a mismatch between physician perception and effective drivers of behavior change. Further investigation may focus on determining the size and longevity of the isolated impact of a schedule request incentive, as one might expect diminishing marginal utility.

Effectiveness of HIV self-testing when offered within assisted partner services in Western Kenya (APS-HIVST Study): a cluster randomized controlled trial.

INTRODUCTION: Assisted partner services (APS) is an effective strategy for increasing HIV testing, new diagnosis, and linkage to care among sexual partners of people living with HIV (PLWH). APS can be resource intensive as it requires community tracing to locate each partner named and offer them testing. There is limited evidence for the effectiveness of offering HIV self-testing (HIVST) as an option for partner testing within APS. METHODS: We conducted a cluster randomized controlled trial comparing provider-delivered HIV testing (Standard APS) versus offering partners the option of provider-delivered testing or HIVST (APS+HIVST) at 24 health facilities in Western Kenya. Facilities were randomized 1:1 and we conducted intent-to-treat analyses using Poisson generalized linear mixed models to estimate intervention impact on HIV testing, new HIV diagnoses, and linkage to care. All models accounted for clustering at the clinic level and new diagnoses and linkage models were adjusted for individual-level age, sex, and income a priori. RESULTS: From March to December 2021, 755 index clients received APS and named 5054 unique partners. Among these, 1408 partners reporting a prior HIV diagnosis were not eligible for HIV testing and were excluded from analyses. Of the remaining 3646 partners, 96.9% were successfully contacted for APS and tested for HIV: 2111 (97.9%) of 2157 in the APS+HIVST arm and 1422 (95.5%) of 1489 in the Standard APS arm. In the APS+HIVST arm, 84.6% (1785/2111) tested via HIVST and 15.4% (326/2111) received provider-delivered testing. Overall, 16.7% of the 3533 who tested were newly diagnosed with HIV (APS+HIVST = 357/2111 [16.9%]; Standard APS = 232/1422 [16.3%]). Of the 589 partners who were newly diagnosed, 90.7% were linked to care (APS+HIVST = 309/357 [86.6%]; Standard APS = 225/232 [97.0%]). There were no significant differences between the two arms in HIV testing (relative risk [RR]: 1.02, 95% CI: 0.96-1.10), new HIV diagnoses (adjusted RR [aRR]: 1.03, 95% CI: 0.76-1.39) or linkage to care (aRR: 0.88, 95% CI: 0.74-1.06). CONCLUSIONS: There were no differences between APS+HIVST and Standard APS, demonstrating that integrating HIVST into APS continues to be an effective strategy for identifying PLWH by successfully reaching and HIV testing >95% of elicited partners, newly diagnosing with HIV one in six of those tested, >90% of whom were linked to care. CLINICAL TRIAL NUMBER: NCT04774835.

Serial paired arterial and jugular venous point-of-care values in dogs undergoing manual basic life support.

OBJECTIVE: To evaluate differences in point-of-care (POC) variables obtained from arterial and jugular venous blood in dogs undergoing manual basic life support (BLS) and report changes over time. DESIGN: Experimental study. SETTING: Small animal research facility. ANIMALS: Twenty-four purpose-bred research dogs. INTERVENTIONS: Dogs were anesthetized, and arterial catheters were placed before euthanasia. One minute after cardiopulmonary arrest, BLS consisting of manual chest compressions and ventilation delivered via endotracheal intubation, face mask, mouth-to-nose, or no ventilation was initiated. Paired arterial and jugular venous blood samples were obtained for POC testing before euthanasia (T0), at 3 minutes (T3), and at 6 minutes (T6) into BLS. MEASUREMENTS AND MAIN RESULTS: The association of POC variables with arterial or venous sample type while controlling for type of ventilation and sampling timepoint was determined using a generalized linear mixed model. Variables obtained from arterial and venous blood samples were compared over time using repeated measures ANOVA or Friedman test. Pao2, anion gap, potassium, chloride, glucose concentration, and PCV were significantly higher in arterial blood samples compared with venous samples (P < 0.03). By T6, arterial glucose concentration, arterial and venous base excess, venous pH, and plasma lactate, potassium, creatinine, bicarbonate, and sodium concentrations were significantly increased, and arterial and venous Po2, ionized calcium concentration, PCV, and total plasma protein concentration were significantly decreased from T0 (P < 0.05). CONCLUSIONS: Although statistically significant, arteriovenous differences and changes in POC blood variables during BLS were small and not clinically relevant over time. Given the challenges of arterial blood sampling, it may be reasonable to pursue venous blood sampling during CPR. Further studies in dogs undergoing BLS and advanced life support are needed to better understand the potential clinical role of POC testing during CPR.

Examining barriers to antiretroviral therapy initiation in infants living with HIV in sub-Saharan Africa despite the availability of point-of-care diagnostic testing: a narrative systematic review.

INTRODUCTION: Antiretroviral therapy (ART) initiation in infants living with HIV before 12 weeks of age can reduce the risk of mortality by 75%. Point-of-care (POC) diagnostic testing is critical for prompt ART initiation; however, despite its availability, rates of ART initiation are still relatively low before 12 weeks of age. This systematic review describes the barriers to ART initiation in infants before 12 weeks of age, despite the availability of POC. METHODS: This systematic review used a narrative synthesis methodology. We searched PubMed and Scopus using search strategies that combined terms of multiple variants of the keywords "early infant initiation on antiretroviral therapy," "barriers" and "sub-Saharan Africa" (initial search 18th January 2023; final search 1st August 2023). We included qualitative, observational and mixed methods studies that reported the influences of early infant initiation on ART. We excluded studies that reported influences on other components of the Prevention of Mother to Child Transmission cascade. Using a deductive approach guided by the updated Consolidated Framework of Implementation Research, we developed descriptive codes and themes around barriers to early infant initiation on ART. We then developed recommendations for interventions for the identified barriers using the action, actor, target and time framework from the codes. RESULTS: Of the 266 abstracts reviewed, 52 full-text papers were examined, of which 12 papers were included. South Africa had most papers from a single country (n = 3) and the most reported study design was retrospective (n = 6). Delays in ART initiation beyond 12 weeks in infants 0-12 months were primarily associated with health facility and maternal factors. The most prominent barriers identified were inadequate resources for POC testing (including human resources, laboratory facilities and patient follow-up). Maternal-related factors, such as limited male involvement and maternal perceptions of treatment and care, were also influential. DISCUSSION: We identified structural barriers to ART initiation at the health system, social and cultural levels. Improvements in the timely allocation of resources for POC testing operations, coupled with interventions addressing social and behavioural barriers among both mothers and healthcare providers, hold a promise for enhancing timely ART initiation in infants. CONCLUSIONS: This paper identifies barriers and proposes strategies for timely ART initiation in infants.

The use of diagnostic ultrasound by primary care physicians in Switzerland - a cross-sectional study.

BACKGROUND: Diagnostic ultrasound has become a bedside tool widely available to many primary care physicians (PCPs) in Europe. It is often used as point-of-care ultrasonography (POCUS) in this setting. In Switzerland, certain POCUS examinations are listed as learning objectives in existing ultrasound training programs (we defined these examinations as swissPOCUS = sPOCUS). Ultrasound performed by PCPs can lead to faster diagnostic workup and reduce referral to secondary care units. However, adequate training is crucial to guarantee high quality. To guide the development of ultrasound training programs for PCPs, this study explores the use of ultrasound in primary care in Switzerland. METHODS: This was a cross-sectional study. We invited PCPs from the Swiss practice-based research network "Sentinella" to collect data on the first 5 daily ultrasounds they ordered or performed themselves. Participating PCPs collected data for 3 months - divided into 4 groups to account for seasonal differences. RESULTS: Out of 188 PCPs invited, 81.9% provided data through an initial questionnaire. 46.8% provided data on 1616 ultrasounds. 56.5% of PCPs had access to ultrasound machines, while 29.8% had completed formal training. 77% of the reported ultrasounds were self-performed; 27% of the reported scans (35% of all self-performed scans) were performed by PCPs with incomplete or no formal training. The main areas of interest were the abdominal (57.9%) and the musculoskeletal (22%) region. 36.9% of reported examinations were sPOCUS exams. Among PCPs with access to US machines, the percentages of referred examinations were similar for sPOCUS (11.9%) and non-sPOCUS (11.3%) indications. However, some sPOCUS musculoskeletal ultrasounds were often referred (e.g. tendon/ligament/muscle injuries or cutaneous/subcutaneous tumour). CONCLUSION: Most Swiss PCPs had access to ultrasound equipment and performed a majority of both sPOCUS and non-sPOCUS scans themselves, often without or with incomplete training. This reflects the fact that POCUS was only recently introduced in Switzerland. There is a need for easily accessible POCUS training programs aimed at PCPs in Switzerland. Training courses for PCPs should focus on abdominal and musculoskeletal ultrasound, because these were the most common sites for scans, and because some sPOCUS musculoskeletal examinations showed a particularly high percentage of referral.

The cost-effectiveness of integrating simplified HCV testing into HIV pre-exposure prophylaxis (PrEP) and treatment services among men who have sex with men in Taiwan.

Background: Simplified hepatitis C virus (HCV) testing integrated into existing HIV services has the potential to improve HCV diagnoses and treatment. We evaluated the cost-effectiveness of integrating different simplified HCV testing strategies into existing HIV pre-exposure prophylaxis (PrEP) and treatment services among men who have sex with men (MSM) in Taiwan. Methods: Mathematical modeling was used to assess the cost-effectiveness of integrating simplified HCV tests (point-of-care antibody, reflex RNA, or immediate point-of-care RNA) with HCV treatment into existing HIV prevention and care for MSM from a healthcare perspective. The impact of increasing PrEP and HIV treatment coverage among MSM in combination with these HCV testing strategies was also considered. We reported lifetime costs (2022 US dollars) and quality-adjusted life years (QALYs) and calculated incremental cost-effectiveness ratios (ICERs) with a 3% annual discounting rate. Findings: Point-of-care HCV antibody and reflex RNA testing are cost-effective compared to current HCV testing in all PrEP and HIV treatment coverage scenarios (ICERs <$32,811/QALY gained). Immediate point-of-care RNA testing would be only cost-effective compared to the current HCV testing if coverage of HIV services remained unchanged. Point-of-care antibody testing in an unchanged HIV services coverage scenario and all simplified HCV testing strategies in scenarios that increased both HIV PrEP and treatment coverage form an efficient frontier, indicating best value for money strategies. Interpretation: Our findings support the integration of simplified HCV testing and people-centered services for MSM and highlight the economic benefits of integrating simplified HCV testing into existing services for MSM alongside HIV PrEP and treatment. Funding: This study was made possible as part of a research-funded PhD being undertaken by HJW under the UNSW Sydney Scientia scholarship and was associated with the Rapid Point of Care Research Consortium for infectious disease in the Asia Pacific (RAPID), which is funded by an NHMRC Centre for Research Excellence. JG is supported by a National Health and Medical Research Council Investigator Grant (1176131).

Evaluation of Xpert point-of-care assays for detection of HIV infection in persons using long-acting cabotegravir for pre-exposure prophylaxis.

Detection of HIV infection may be challenging in persons using long-acting cabotegravir (CAB-LA) pre-exposure prophylaxis (PrEP) due to viral suppression and reduced/delayed antibody production. We evaluated two point-of-care tests for detecting HIV infection in persons who received CAB-LA in the HPTN 083 trial. Samples were obtained from 12 participants who received CAB-LA and had delayed detection of HIV infection using HIV rapid tests and an antigen/antibody test (52 plasma samples; 18 dried blood spot [DBS] samples). Plasma samples were tested with the Xpert HIV-1 Viral Load XC test (Xpert VL-XC); DBS samples were tested with the total nucleic acid Xpert HIV-1 Qual XC test (Xpert Qual-XC). Results from these assays were compared to results from three reference, laboratory-based, plasma RNA assays (Aptima HIV-1 Qualitative assay [Aptima Qual]; Aptima HIV-1 Quant DX Assay [Aptima Quant]; cobas HIV-1/HIV-2 Qualitative Test [cobas]). HIV RNA was detected with all four plasma assays for all samples with viral loads (VLs) ≥ 200 copies/mL; the number of samples with VLs < 200 copies/mL with HIV RNA detected was: Xpert VL-XC: 19/26 (73.1%); Aptima Qual: 17/26 (65.4%); Aptima Quant: 17/26 (65.4%); and cobas: 12/21 (57.1%). The Xpert Qual-XC assay was positive for all DBS samples with VLs ≥ 200 copies/mL and 1/10 DBS with VLs < 200 copies/mL. The performance of the Xpert VL-XC assay was comparable to the reference assays for detecting HIV infection in these cases. The Xpert Qual-XC assay was less sensitive than plasma-based HIV RNA assays for detecting HIV in the setting of CAB-LA PrEP. IMPORTANCE: HIV RNA assays can detect HIV infections earlier than HIV rapid tests or Ag/Ab tests in persons using CAB-LA PrEP. Earlier HIV diagnosis could allow for earlier treatment initiation and reduced risk of INSTI resistance. POC tests may help detect HIV infection before CAB-LA administration and may be more accessible than laboratory-based assays in some settings. In this study, the POC Xpert VL-XC assay detected HIV RNA in most samples from individuals who received CAB-LA PrEP and had delayed detection of HIV infection with HIV rapid tests and an Ag/Ab test. The performance of this assay was similar to laboratory-based HIV RNA assays in this cohort. The POC Xpert Qual-XC assay detects both HIV RNA and DNA, with a higher viral load cutoff for RNA detection. This assay was negative for most lower viral load samples and did not offer an advantage for HIV screening in persons using CAB-LA PrEP.

Point-of-Care Newborn Screening for Sickle Cell Disease at Selected Health Facilities in the Gambia.

Sickle cell disease (SCD) contributes significantly to childhood morbidity and mortality in sub-Saharan Africa. Early diagnosis through newborn screening (NBS) and subsequent comprehensive follow-up care will reduce the burden. Up till now, the prevalence of SCD among newborns remains unknown in The Gambia and there is no national NBS programme to address this significant public health issue. We assessed the real-time frequency of SCD in the country and determined differences in the pattern of SCD phenotypes among different ethnic groups. A preliminary prospective feasibility study was done in eight purposively selected hospitals in the seven Health Administrative Regions and Banjul. Consecutive newborn babies delivered or managed in these facilities were screened using HemoTypeSC, a sensitive and specific ELISA-based point-of-care test (POCT). Babies identified as SCD with HemoTypeSC were retested at age ≥6 months using alkaline cellulose acetate hemoglobin electrophoresis (ACAE). Head-to-head comparison between HemoType screening and gold standard HPLC could not be done. 1,168 newborn babies were screened from April 14 to August 12, 2023. Fifteen (1.3%) had homozygous HbS (HbSS), two (0.2%) heterozygous for HbS and HbC (HbSC), 204 (17.5%) had sickle cell trait (HbAS), four (0.3%) heterozygous for HbA and HbC (HbAC), and 943 (80.7%) had normal hemoglobin (HbAA). The 17 with SCD (HbSS and HbSC) comprised of 7 (2.2%) of 324 Fula; 6 (1.4%) of 426 Mandinka; 2 (1.6%) of 125 Jola and 2 (1.3%) of 150 Wolof. Fourteen (82.4%) of the 17 accepted the diagnosis and were enrolled into the SCD program. For these 14, HemoTypeSC had 100% sensitivity with ACAE when repeated at age ≥6 months. In addition to determining the real-time newborn prevalence of SCD and trait in The Gambia for the first time, this pilot study showed that SCD-POCT is feasible in Gambian health facilities.

Point-of-care isothermal nucleic acid amplification tests: progress and bottlenecks for extraction-free sample collection and preparation.

INTRODUCTION: Suitable sample collection and preparation methods are essential to enable nucleic acid amplification testing at the point of care (POC). Strategies that allow direct isothermal nucleic acid amplification testing (iNAAT) of crude sample lysate without the need for nucleic acid extraction minimize time to result as well as the need for operator expertise and costly infrastructure. AREAS COVERED: The authors review research to understand how sample matrix and preparation affect the design and performance of POC iNAATs. They focus on approaches where samples are directly combined with liquid reagents for preparation and amplification via iNAAT strategies. They review factors related to the type and method of sample collection, storage buffers, and lysis strategies. Finally, they discuss RNA targets and relevant regulatory considerations. EXPERT OPINION: Limitations in sample preparation methods are a significant technical barrier preventing implementation of nucleic acid testing at the POC. The authors propose a framework for co-designing sample preparation and amplification steps for optimal performance with an extraction-free paradigm by considering a sample matrix and lytic strategy prior to an amplification assay and readout. In the next 5 years, the authors anticipate increasing priority on the co-design of sample preparation and iNAATs.

An Ultrasensitive Biosensor for Probing Subcellular Distribution and Mitochondrial Transport of l-2-Hydroxyglutarate.

l-2-Hydroxyglutarate (l-2-HG) is a functionally compartmentalized metabolite involved in various physiological processes. However, its subcellular distribution and mitochondrial transport remain unclear owing to technical limitations. In the present study, an ultrasensitive l-2-HG biosensor, sfLHGFRH, composed of circularly permuted yellow fluorescent protein and l-2-HG-specific transcriptional regulator, is developed. The ability of sfLHGFRH to be used for analyzing l-2-HG metabolism is first determined in human embryonic kidney cells (HEK293FT) and macrophages. Then, the subcellular distribution of l-2-HG in HEK293FT cells and the lower abundance of mitochondrial l-2-HG are identified by the sfLHGFRH-supported spatiotemporal l-2-HG monitoring. Finally, the role of the l-glutamate transporter SLC1A1 in mitochondrial l-2-HG uptake is elucidated using sfLHGFRH. Based on the design of sfLHGFRH, another highly sensitive biosensor with a low limit of detection, sfLHGFRL, is developed for the point-of-care diagnosis of l-2-HG-related diseases. The accumulation of l-2-HG in the urine of patients with kidney cancer is determined using the sfLHGFRL biosensor.

Accuracy of point-of-care capillary blood sugar measurements in critically ill patients: An observational study.

Background: Accurately monitoring blood glucose levels is vital for critically ill individuals. Point-of-care (POC) glucose meters are commonly used in local intensive care units (ICUs). This study aimed to assess the precision of POC glucose meter readings in critically ill individuals with specific evaluation in patients with and without shock against the reference standard of venous blood glucose measurements. Methods: An observational study was done on adult patients admitted in the ICU at a teaching institution. Capillary blood samples were collected from the patient's fingertip using lancet device with aseptic measures. The sample was analyzed using the GlucoCare Sense Glucometer (RMD Mediaids Limited, Taiwan). At the same time, 2 ml of blood was drawn from the patient's peripheral veins and analyzed by glucose oxidase-peroxidase method as reference. Results: POC glucose measurements averaged 140 ± 20.23 mg/dl, while laboratory values were recorded as 116.10 ± 17.13 mg/dl. The difference between the two methods was 24.34 ± 12.01 mg/dl. A strong correlation (r = 0.805) was found between capillary and laboratory blood glucose levels, indicating a significant association (P < 0.0001). Twenty-two (44%) patients were in shock during the study. The mean difference between laboratory and POC blood glucose levels was higher in patients with circulatory shock (36.82 ± 4.84 mg/dl) than those without shock (14.61 ± 4.49 mg/dl), P < 0.05. Conclusion: POC glucose meters may lead to underdetection of hypoglycemia in critically ill patients, as their values are higher than laboratory values. Moreover, the results showed that POC glucometers are inaccurate for monitoring glucose in hypotensive patients in shock. Standard venous glucose monitoring methods may be more appropriate for these patients.

Retrospect, advances and challenges in Chagas disease diagnosis: a comprehensive review.

Chagas disease, caused by Trypanosoma cruzi, affects millions worldwide. The 2030 WHO roadmap aims to eliminate it as a public health concern, emphasising the need for timely diagnosis to enhance treatment access. Current diagnostic algorithms, which rely on multiple tests, have prolonged turnaround times. This proves particularly problematic in resource-limited settings. Addressing this issue necessitates the validation and adoption of innovative tools. We explore recent developments in Chagas disease diagnosis, reviewing historical context and advancements. Despite progress, challenges persist. This article contributes to the understanding of current and future directions in this neglected healthcare area. Parasitological methods are simple but exhibit low sensitivity and require supplementary tests. Molecular methods, with automation potential, allow quantification and higher throughput. Serological tools show good performance but struggle with parasite antigenic diversity. Prioritising point-of-care tests is crucial for widespread accessibility and could offer a strategy to control disease impact. Ultimately, balancing achievements and ongoing obstacles is essential for comprehensive progress.