RESUMEN

BACKGROUND: Globally, around 7 to 20 million people are believed to be suffering from coinfection with both hepatitis B virus (HBV) and hepatitis C virus (HCV). The loop-mediated isothermal amplification (LAMP) approach, introduced by Notomi and colleagues, has undergone substantial advancements as an effective molecular tool that enables the simultaneous analysis of multiple samples in a single tube. METHODS: The present study examined the simultaneous detection of HBV and HCV in a single tube using melt curve analysis multiplex LAMP (mLAMP), which is based on the identification of unique melting peak temperatures. Selected regions for primer design including the S gene of HBV and the UTR gene of HCV. Primer optimization is initially performed through individual HBV and HCV LAMP analysis. Following the optimization process, the mLAMP assay was evaluated by optimizing the multiplex reaction mixture, determining the reaction time, and analyzing the limit of detection (LOD). The results are also analyzed using lateral flow dipsticks (LFD), which enable the visual detection of HBV and HCV by adding 20 pmol FITC-labeled LF primers into the reaction mixture prior the mLAMP. RESULTS: The LOD for the mLAMP assay was determined as 10 copies/µl, and no cross-reactivity with other microorganisms was detected. The detection results obtained from patient plasma were also visually demonstrated using LFD, and displayed significant concordance with those obtained from Real-Time Polymerase Chain Assay. The mLAMP assay revealed a diagnostic sensitivity of 95% for detecting the HBV, and LOD is 90% for HCV. The overall diagnostic sensitivity of the mLAMP assay for both viruses was 85%. The assay confirmed a specificity of 100%. CONCLUSION: The mLAMP assay displays significant promise for analyzing coinfected samples by simultaneously detecting the dual targets HBV and HCV within a set temperature of 62 °C, all within a time frame of 1 h. Additionally, when paired with disposable LFD, the mLAMP assay enables rapid visual detection of assay results in a matter of minutes. The result contributes to the mLAMP assay being highly suitable for coinfection screening, particularly in field conditions.

Asunto(s)

Coinfección , Hepacivirus , Virus de la Hepatitis B , Hepatitis B , Hepatitis C , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Sensibilidad y Especificidad , Humanos , Técnicas de Amplificación de Ácido Nucleico/métodos , Hepatitis C/diagnóstico , Hepatitis C/virología , Hepatitis C/complicaciones , Hepatitis B/diagnóstico , Hepatitis B/virología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Coinfección/diagnóstico , Coinfección/virología , Técnicas de Diagnóstico Molecular/métodos , Límite de Detección , Cartilla de ADN/genética

RESUMEN

PURPOSE: Blood culture (BC) is the gold standard for diagnosing blood stream infections (BSI) but is limited by long turnaround times (TAT) and low detection rate. The T2 Magnetic Resonance method (T2MR) offers a rapid, culture-independent alternative. The objective of this study was to compare the performance of the T2Bacteria assay to BCs in a real-world setting. METHODS: Retrospective comparative study consisting of T2Bacteria samples and BCs sampled within 72 h from the T2Bacteria sample. The primary outcome was detections by BC and T2Bacteria, respectively. The secondary outcome was difference in TAT. RESULTS: In total, 640 episodes were included, consisting of 640 T2Bacteria samples and 2,117 BCs. A median of three BCs was collected for each T2Bacteria sample. Overall positivity was 101 (15.8%) by either method. In 29 (28.7%) episodes, both T2Bacteria and BC were concordantly positive. In discordant episodes, 46/101 (45.5%) episodes were T2Bacteria positive/BC negative and 26/101 (25.7%) were T2Bacteria negative/BC positive (McNemar χ2, p < 0,05). In T2Bacteria positive/BC negative episodes, eight had growth of the same microorganism in a non-BC culture. Median (IQR) TAT for BC was 35 h and 30 min (25 h 50 min - 45 h 24 min), compared to 21 h and 3 min (17 h 6 min - 27 h 30 m) for T2Bacteria (p < 0.001), with longer delays for samplings occurring outside work hours. CONCLUSIONS: The study highlights a high discordance between T2Bacteria and BC and suggests complementary roles of the methods in BSI diagnostics. Furthermore, it is crucial to improve TAT by reducing preanalytical delays.

Asunto(s)

Bacteriemia , Cultivo de Sangre , Humanos , Estudios Retrospectivos , Cultivo de Sangre/métodos , Bacteriemia/diagnóstico , Bacteriemia/microbiología , Femenino , Masculino , Persona de Mediana Edad , Bacterias/aislamiento & purificación , Bacterias/clasificación , Anciano

RESUMEN

Tick-borne encephalitis virus (TBEV), a zoonotic pathogen, can cause severe neurological complications and fatal outcomes in humans. Early diagnosis of TBEV infection is crucial for clinical practice. Although serological assays are frequently employed for detection, the lack of antibodies in the early stages of infection and the cross-reactivity of antibodies limit their efficacy. Conventional molecular diagnostic methods such as RT-qPCR can achieve early and accurate identification but require specialized instrumentation and professionals, hindering their application in resource-limited areas. Our study developed a rapid and visual TBEV molecular detection method by combining RT-recombinase-aided amplification, the CRISPR/Cas13a system, and lateral flow dipsticks. The diagnostic sensitivity of this method is 50 CFU/ml, with no cross-reactivity with a variety of viruses. The detection can be carried out within 1 h at a temperature between 37 and 42 °C, and the results can be visually determined without the need for complex instruments and professionals. Subsequently, this assay was used to analyze clinical samples from 15 patients suspected of TBEV infection and 10 healthy volunteers, and its sensitivity and specificity reached 100 %, which was consistent with the results of RT-qPCR. These results indicate that this new method can be a promising point-of-care test for the diagnosis of tick-borne encephalitis.

Asunto(s)

Sistemas CRISPR-Cas , Virus de la Encefalitis Transmitidos por Garrapatas , Recombinasas , Virus de la Encefalitis Transmitidos por Garrapatas/genética , Humanos , Recombinasas/metabolismo , Técnicas de Amplificación de Ácido Nucleico/métodos , Encefalitis Transmitida por Garrapatas/diagnóstico , Encefalitis Transmitida por Garrapatas/virología , Encefalitis Transmitida por Garrapatas/sangre , Sensibilidad y Especificidad , ARN Viral/genética , Técnicas de Diagnóstico Molecular/métodos

RESUMEN

The purpose of this study was to assess changes in time to optimal therapy (TTOT) for bacteremia due to select organisms after implementation of the BioFire® FilmArray® blood culture identification panels at two community teaching hospitals. TTOT (days) was similar in Pre-BCID compared to BCID1 and BCID2 [(2.48 vs. 2.65, p=0.10); (2.48 vs. 2.37, p=0.27)]. There were no significant differences in time to effective antimicrobial therapy between groups. However, there were significantly more therapy changes and appropriate carbapenem use within 24 hours of the Gram stain result for gram-negative organisms in the BCID2 arm compared to the Pre-BCID arm. Additionally, a significant reduction in the duration of vancomycin for gram-positive organisms was noted in the BCID2 arm compared to the Pre-BCID arm. These findings suggest that the incorporation of the BCID2 panel resulted in changes in prescribing practices, leading to more appropriate antimicrobial utilization in a subset of patients.

Asunto(s)

Antibacterianos , Bacteriemia , Cultivo de Sangre , Tiempo de Tratamiento , Cultivo de Sangre/métodos , Cultivo de Sangre/estadística & datos numéricos , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Tiempo de Tratamiento/estadística & datos numéricos , Antibacterianos/administración & dosificación , Prescripciones de Medicamentos/estadística & datos numéricos , Estudios Retrospectivos , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años

RESUMEN

Antibiotic resistance is a global challenge likely to cost trillions of dollars in excess costs in the health system and more importantly, millions of lives every year. A major driver of resistance is the absence of susceptibility testing at the time a healthcare worker needs to prescribe an antimicrobial. The effect is that many prescriptions are unintentionally wasted and expose mutable organisms to antibiotics increasing the risk of resistance emerging. Often simplistic solutions are applied to this growing issue, such as a naïve drive to increase the speed of drug susceptibility testing. This puts a spotlight on a technological solution and there is a multiplicity of such candidate DST tests in development. Yet, if we do not define the necessary information and the speed at which it needs to be available in the clinical decision-making progress as well as the necessary integration into clinical pathways, then little progress will be made. In this chapter, we place the technological challenge in a clinical and systems context. Further, we will review the landscape of some promising technologies that are emerging and attempt to place them in the clinic where they will have to succeed.

Asunto(s)

Antibacterianos , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Humanos , Farmacorresistencia Bacteriana/efectos de los fármacos , Bacterias/efectos de los fármacos

RESUMEN

BACKGROUND AND AIMS: Strategies to assess patients with suspected acute myocardial infarction (AMI) using a point-of-care (POC) high-sensitivity cardiac troponin I (hs-cTnI) assay may expedite emergency care. A 2-h POC hs-cTnI strategy for emergency patients with suspected AMI was derived and validated. METHODS: In two international, multi-centre, prospective, observational studies of adult emergency patients (1486 derivation cohort and 1796 validation cohort) with suspected AMI, hs-cTnI (Siemens Atellica® VTLi) was measured at admission and 2 h later. Adjudicated final diagnoses utilized the hs-cTn assay in clinical use. A risk stratification algorithm was derived and validated. The primary diagnostic outcome was index AMI (Types 1 and 2). The primary safety outcome was 30-day major adverse cardiac events incorporating AMI and cardiac death. RESULTS: Overall, 81 (5.5%) and 88 (4.9%) patients in the derivation and validation cohorts, respectively, had AMI. The 2-h algorithm defined 66.1% as low risk with a sensitivity of 98.8% [95% confidence interval (CI) 89.3%-99.9%] and a negative predictive value of 99.9 (95% CI 99.2%-100%) for index AMI in the derivation cohort. In the validation cohort, 53.3% were low risk with a sensitivity of 98.9% (95% CI 92.4%-99.8%) and a negative predictive value of 99.9% (95% CI 99.3%-100%) for index AMI. The high-risk metrics identified 5.4% of patients with a specificity of 98.5% (95% CI 96.6%-99.4%) and a positive predictive value of 74.5% (95% CI 62.7%-83.6%) for index AMI. CONCLUSIONS: A 2-h algorithm using a POC hs-cTnI concentration enables safe and efficient risk assessment of patients with suspected AMI. The short turnaround time of POC testing may support significant efficiencies in the management of the large proportion of emergency patients with suspected AMI.

Asunto(s)

Algoritmos , Infarto del Miocardio , Troponina I , Humanos , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/sangre , Masculino , Femenino , Estudios Prospectivos , Troponina I/sangre , Anciano , Persona de Mediana Edad , Sistemas de Atención de Punto , Biomarcadores/sangre , Medición de Riesgo/métodos , Sensibilidad y Especificidad , Pruebas en el Punto de Atención

RESUMEN

Identifying organisms directly from positive blood culture bottles using matrix-assisted laser desorption-ionisation time-of-flight mass spectrometry (MALDI-TOF MS) has many advantages to patients, clinical services, and laboratories. However, few published methods have demonstrated good performance using the current BioMérieux culture bottles and MALDI-TOF system: BacT/Alert FAN plus and Vitek MS. The effect of transporting bottles on test performance has not been assessed for any direct-from-bottle MS method. In this study, 802 positive blood culture bottles were analysed including 234 requiring inter-laboratory transport, using a method involving protein extraction with formic acid and acetonitrile. Correct identification rates were high for Staphylococcus aureus (58/58 of new diagnostic samples), Enterococcus faecalis (27/27), Gram-negative bacilli (160/176, 90.1%), and coagulase-negative Staphylococcus species (108/132, 81.8%). Three false identifications were made, none with clinical significance. For Gram-positive cocci in pairs or chains, more correct identifications were made from bottles analysed immediately compared to transported bottles (67% vs 44%, p=0.016), and longer transport time was associated with slightly lower probability of correct identification (OR 0.984 per additional hour, p=0.040). Transportation was not associated with a difference for other organism types. This technique is a vastly more cost-effective alternative to molecular techniques for rapid identification of bacteraemia isolates, and performance is minimally affected by inter-laboratory transport of bottles at ambient temperature.

Asunto(s)

Cultivo de Sangre , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Cultivo de Sangre/métodos , Manejo de Especímenes/métodos , Bacteriemia/diagnóstico , Bacteriemia/microbiología , Técnicas Bacteriológicas/métodos

RESUMEN

Sepsis is a major health concern globally, and identification of the causative organism usually takes several days. Furthermore, molecular amplification using whole blood from patients with sepsis remains challenging because of primer cross-reactivity with human DNA, which can delay appropriate clinical intervention. To address these concerns, we designed primers that could reduce cross-reactivity. By evaluating these primers against human DNA, we confirmed that the cross-reactivity observed with conventional primers was notably absent. In silico PCR further demonstrated the specificity and efficiency of the designed primers across 23 bacterial species that are often associated with sepsis. When tested using blood samples from sepsis patients, the designed primers showed moderate sensitivity and high specificity. Surprisingly, our method identified bacteria even in samples that were detected at other sites but tested negative using conventional blood culture methods. Although we identified some challenges, such as contamination with Acetobacter aceti due to the saponin pretreatment of samples, the developed method demonstrates remarkable potential for rapid identification of the causative organisms of sepsis and provides a new avenue for diagnosis in clinical practice.

Asunto(s)

Bacterias , Cartilla de ADN , Sensibilidad y Especificidad , Sepsis , Humanos , Sepsis/microbiología , Sepsis/diagnóstico , Sepsis/sangre , Cartilla de ADN/genética , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/clasificación , ADN Bacteriano/genética , Reacción en Cadena de la Polimerasa/métodos , Reacciones Cruzadas , ADN/sangre , ADN/genética

RESUMEN

OBJECTIVE: Globally, there are estimated to be 2.9 million cholera cases annually. Early detection of cholera outbreaks is crucial for resource allocation for case management and for targeted interventions to be delivered to stop the spread of cholera. In resource limited settings such as Eastern Democratic Republic of the Congo (DRC), there is often limited laboratory capacity for analysing stool samples for cholera by bacterial culture. Therefore, rapid diagnostic tests (RDTs) for cholera present a promising tool to rapidly test stool samples in a health facility setting for cholera. Our objective is to evaluate the Crystal VC O1 RDT for cholera detection compared with bacterial culture and polymerase chain reaction (PCR) for Vibrio cholerae. METHODS: From March 2020 to December 2022, stool samples were collected from 644 diarrhoea patients admitted to 94 health facilities in Bukavu in Eastern DRC. Patient stool samples were analysed by Crystal VC O1 RDT for cholera and by bacterial culture and PCR for V. cholerae O1. RESULTS: Twenty six percent of diarrhoea patients (166/644) had stool samples positive for cholera by RDT, and 24% (152/644) had stool samples positive for V. cholerae O1 by bacterial culture or PCR. The overall specificity and sensitivity of the Crystal VC O1 RDT by direct testing was 94% (95% confidence interval [CI]: 92%-96%) and 90% (95% CI, 84%-94%), respectively, when compared with either a positive result by bacterial culture or PCR. CONCLUSION: Our findings suggest that the Crystal VC O1 RDT presents a promising tool for cholera surveillance in this cholera endemic setting in sub-Saharan Africa.

Asunto(s)

Cólera , Heces , Vibrio cholerae O1 , Humanos , Cólera/diagnóstico , Cólera/prevención & control , Cólera/epidemiología , República Democrática del Congo/epidemiología , Vibrio cholerae O1/aislamiento & purificación , Masculino , Heces/microbiología , Femenino , Adulto , Adolescente , Persona de Mediana Edad , Adulto Joven , Sensibilidad y Especificidad , Niño , Diarrea/prevención & control , Diarrea/microbiología , Diarrea/diagnóstico , Preescolar , Reacción en Cadena de la Polimerasa , Pruebas Diagnósticas de Rutina/métodos , Lactante , Anciano , Brotes de Enfermedades/prevención & control , Prueba de Diagnóstico Rápido

RESUMEN

Introduction: Brain tumors are a major source of disease burden in pediatric population, with the most common tumor types being pilocytic astrocytoma, ependymoma and medulloblastoma. In every tumor entity, surgery is the cornerstone of treatment, but the importance of gross-total resection and the corresponding patient prognosis is highly variant. However, real-time identification of pediatric CNS malignancies based on the histology of the frozen sections alone is especially troublesome. We propose a novel method based on differential mobility spectrometry (DMS) analysis for rapid identification of pediatric brain tumors. Methods: We prospectively obtained tumor samples from 15 pediatric patients (5 pilocytic astrocytomas, 5 ependymomas and 5 medulloblastomas). The samples were cut into 36 smaller specimens that were analyzed with the DMS. Results: With linear discriminant analysis algorithm, a classification accuracy (CA) of 70% was reached. Additionally, a 75% CA was achieved in a pooled analysis of medulloblastoma vs. gliomas. Discussion: Our results show that the DMS is able to differentiate most common pediatric brain tumor samples, thus making it a promising additional instrument for real-time brain tumor diagnostics.

RESUMEN

We assessed the performance of GenMark's ePlex® Blood Culture Identification (BCID) Panels for overall agreement of organism identification and resistance mechanism detection with standard microbiologic methods. This study included patients with a positive blood culture from May 2020 to January 2021. The primary outcomes were to assess concordance of ePlex® organism identification with standard identification methods and concordance of ePlex® genotypic resistance mechanism detection with standard phenotypic susceptibility testing. Secondary outcomes included panel specific performance and characterization of antimicrobial stewardship opportunities. The overall identification concordance rate in 1276 positive blood cultures was 98.1%. The overall concordance for the presence of resistance markers was 98.2% and concordance for the absence of resistance markers was 100%. A majority of ePlex® results (69.5%) represented opportunities for potential antimicrobial stewardship intervention. High concordance rates between the ePlex® BCID panels and standard identification and susceptibility methods enable utilization of results to guide rapid antimicrobial optimization.

Asunto(s)

Antibacterianos , Programas de Optimización del Uso de los Antimicrobianos , Cultivo de Sangre , Pruebas de Sensibilidad Microbiana , Humanos , Cultivo de Sangre/métodos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Bacterias/genética , Bacterias/clasificación , Farmacorresistencia Bacteriana/genética , Bacteriemia/microbiología , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Genotipo

RESUMEN

This study assessed the performance of the BioFire Blood Culture Identification 2 (BCID2) panel in identifying microorganisms and antimicrobial resistance (AMR) profiles in positive blood cultures (BCs) and its influence on turnaround time (TAT) compared with conventional culture methods. We obtained 117 positive BCs, of these, 102 (87.2%) were correctly identified using BCID2. The discordance was due to off-panel pathogens detected by culture (n = 13), and additional pathogens identified by BCID2 (n = 2). On-panel pathogen concordance between the conventional culture and BCID2 methods was 98.1% (102/104). The conventional method detected 19 carbapenemase-producing organisms, 14 extended-spectrum beta-lactamase-producing Enterobacterales, 18 methicillin-resistant Staphylococcus spp., and four vancomycin-resistant Enterococcus faecium. BCID2 correctly predicted 53 (96.4%) of 55 phenotypic resistance patterns by detecting AMR genes. The TAT for BCID2 was significantly lower than that for the conventional method. BCID2 rapidly identifies pathogens and AMR genes in positive BCs.

Asunto(s)

Cultivo de Sangre , Reacción en Cadena de la Polimerasa Multiplex , Reacción en Cadena de la Polimerasa Multiplex/métodos , Humanos , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana/genética , Proteínas Bacterianas/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/efectos de los fármacos , Enterococos Resistentes a la Vancomicina/genética , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Bacteriemia/microbiología , Bacteriemia/diagnóstico

RESUMEN

The recent global pandemic of coronavirus disease 2019 (COVID-19) has enormously promoted the development of diagnostic technology. To control the spread of pandemic diseases and achieve rapid screening of the population, ensuring that patients receive timely treatment, rapid diagnosis has become the top priority in the development of clinical technology. This review article aims to summarize the current rapid nucleic acid diagnostic technologies applied to pandemic disease diagnosis, from rapid extraction and rapid amplification to rapid detection. We also discuss future prospects in the development of rapid nucleic acid diagnostic technologies.

Asunto(s)

COVID-19 , Ácidos Nucleicos , Humanos , Pandemias , COVID-19/diagnóstico , COVID-19/epidemiología , Tecnología , Prueba de COVID-19

RESUMEN

The use of molecular identification panels has advanced the diagnosis for blood stream infections with fast turnaround time and high accuracy. Yet, this technology cannot completely replace conventional blood culture and standardized antibiotic susceptibility testing (AST) given its limitations and occasional false results. Here we present two cases of bacteremia caused by Kluyvera. Its identification and antibiotic resistance were at least partially mispresented by blood culture molecular identification panels on ePlex, Verigene, and Biofire. The detection of CTX-M resistance marker did not align with the susceptibility to the third generation cephalosporins among a wide range of antibiotics for this organism. Conventional extended-spectrum beta-lactamase (ESBL) testing was used to confirm the absence of ESBL. Caution should be taken when managing cases with CTX-M or ESBL detection in blood culture caused by uncommon pathogens. Conventional culture with microbial identification and standardized AST should continue to be the gold standard for routine patient care. IMPORTANCE: This is the first report that highlights the limitations of blood culture molecular identification panels on identifying Kluyvera and its associated antibiotic resistance patterns. Both the false identification and overreporting of antibiotic resistance could mislead the treatment for bacteremia caused by this pathogen. Patient isolation could have been avoided due to the lack of extended-spectrum beta-lactamase (ESBL) activity of the organism. This report emphasizes the importance of confirming rapid identification and antibiotic resistance by molecular technologies with standardized methods. It also provides insight into the development of new diagnostic panels.

Asunto(s)

Antibacterianos , Bacteriemia , Cultivo de Sangre , Kluyvera , Pruebas de Sensibilidad Microbiana , beta-Lactamasas , Femenino , Humanos , Masculino , Antibacterianos/farmacología , Bacteriemia/microbiología , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , beta-Lactamasas/genética , Cultivo de Sangre/métodos , Cefalosporinas/farmacología , Cefalosporinas/uso terapéutico , Errores Diagnósticos , Farmacorresistencia Bacteriana/genética , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/diagnóstico , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Kluyvera/genética , Kluyvera/efectos de los fármacos , Kluyvera/aislamiento & purificación , Anciano de 80 o más Años

RESUMEN

BACKGROUND: Different mosquito control strategies have been implemented to mitigate or prevent mosquito-related public health situations. Modern mosquito control largely relies on multiple approaches, including targeted, specific treatments. Given this, it is becoming increasingly important to supplement these activities with rapid and mobile diagnostic capacities for mosquito-borne diseases. We aimed to create and test the applicability of a rapid diagnostic system for West Nile virus that can be used under field conditions. METHODS: In this pilot study, various types of adult mosquito traps were applied within the regular mosquito monitoring activity framework for mosquito control. Then, the captured specimens were used for the detection of West Nile virus RNA under field conditions with a portable qRT-PCR approach within 3-4 h. Then, positive samples were subjected to confirmatory RT-PCR or NGS sequencing in the laboratory to obtain genome information of the virus. We implemented phylogenetic analysis to characterize circulating strains. RESULTS: A total of 356 mosquito individuals representing 7 species were processed in 54 pools, each containing up to 20 individuals. These pools were tested for the presence of West Nile virus, and two pools tested positive, containing specimens from the Culex pipiens and Anopheles atroparvus mosquito species. As a result of subsequent sequencing, we present the complete genome of West Nile virus and Bagaza virus. CONCLUSIONS: The rapid identification of infected mosquitoes is the most important component of quick response adulticide or larvicide treatments to prevent human cases. The conceptual framework of real-time surveillance can be optimized for other pathogens and situations not only in relation to West Nile virus. We present an early warning system for mosquito-borne diseases and demonstrate its application to aid rapid-response mosquito control actions.

Asunto(s)

Culex , Culicidae , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Animales , Humanos , Virus del Nilo Occidental/genética , Fiebre del Nilo Occidental/diagnóstico , Fiebre del Nilo Occidental/prevención & control , Fiebre del Nilo Occidental/epidemiología , Filogenia , Proyectos Piloto , Control de Mosquitos , Mosquitos Vectores

RESUMEN

Rapid diagnostic tests that differentiate between Gram positive, Gram negative and the absence of aerobic bacteria in milk samples from dairy cows with clinical mastitis can support antimicrobial treatment decisions and contribute to a more prudent use of antimicrobials in the dairy industry. The objective of this study was to evaluate the test characteristics of the novel rapid BACT mastitis test in discriminating causes of clinical mastitis under laboratory conditions. Test outcomes of 155 milk samples from clinical mastitis cases were incubated for 14-16 h in the BACT test and compared to results of bacteriological culture. The accuracy for detection of bacterial growth and Gram positive growth was 91 and 89%, respectively. The BACT test could provide an accurate and relatively fast decision tool for farmers to aid in antimicrobial treatment decisions in cases of clinical mastitis.

Asunto(s)

Mastitis Bovina , Leche , Animales , Femenino , Bovinos , Mastitis Bovina/diagnóstico , Mastitis Bovina/microbiología , Leche/microbiología , Leche/química , Sensibilidad y Especificidad , Técnicas Bacteriológicas/veterinaria , Bacterias Grampositivas/aislamiento & purificación , Industria Lechera/métodos , Bacterias Gramnegativas/aislamiento & purificación , Pruebas Diagnósticas de Rutina/veterinaria , Prueba de Diagnóstico Rápido

RESUMEN

Background: Metagenomic next-generation sequencing (mNGS) testing identifies thousands of potential pathogens in a single blood test, though data on its real-world diagnostic utility are lacking. Objectives: Determine the diagnostic utility of mNGS testing in practice and factors associated with high clinical utility. Design: Retrospective cohort study of mNGS tests ordered from June 2018 through May 2020 at a community teaching hospital. Methods: Tests were included if ordered for diagnostic purposes in patients with probable or high clinical suspicion of infection. Exclusions included patient expiration, hospice care, or transfer outside of the institution. Utility criteria were established a priori by the research team. Two investigators independently reviewed each test and categorized it to either high or low diagnostic utility. Reviewer discordance was referred to a third investigator. The stepwise multiple regression method was used to identify clinical factors associated with high diagnostic utility. Results: Among 96 individual tests from 82 unique patients, 80 tests met the inclusion criteria for analysis. At least one potential pathogen was identified in 58% of tests. Among 112 pathogens identified, there were 74 bacteria, 25 viruses, 12 fungi, and 1 protozoon. In all, 46 tests (57.5%) were determined to be of high diagnostic utility. Positive mNGS tests were identified in 36 (78.3%) and 11 (32.4%) of high and low diagnostic utility tests, respectively (p < 0.001). Antimicrobials were changed after receiving test results in 31 (67.4%) of high utility tests and 4 (11.8%) of low utility tests (p < 0.0001). In the multiple regression model, a positive test [odds ratio (OR) = 10.9; 95% confidence interval (CI), 3.2-44.4] and consultation with the company medical director (OR = 3.6; 95% CI, 1.1-13.7) remained significantly associated with high diagnostic utility. Conclusion: mNGS testing resulted in high clinical utility in most cases. Positive mNGS tests were associated with high diagnostic utility. Consultation with the Karius® medical director is recommended to maximize utility.

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Evaluating the real world utility of using a diagnostic test that uses cell-free DNA to identify bacteria, viruses, fungi and protozoa from blood in hospitalized adult and pediatric patients Our institution has utilized a meta-genomic test that identifies bacteria, DNA-based viruses, fungi and protozoa from blood sample in hospitalized patients to support diagnostics in select clinical cases. We evaluated the utility of these tests in an adult and pediatric population. We found that 58% of the 96 tests from 82 unique patients produced a pathogen. Overall, a majority (58%) of tests were deemed to be of high utility which directly resulted in changes in antimicrobial therapy, selection of duration of therapy, direction for new diagnostics, or avoidance of further need for diagnostics. Positive tests and consultation with the medical director of the laboratory were both associated with high utility of the tests.

RESUMEN

Background. A bloodstream infection (BSI) presents a complex and serious health problem, a problem that is being exacerbated by increasing antimicrobial resistance (AMR).Gap Statement. The current turnaround times (TATs) for most antimicrobial susceptibility testing (AST) methods offer results retrospective of treatment decisions, and this limits the impact AST can have on antibiotic prescribing and patient care. Progress must be made towards rapid BSI diagnosis and AST to improve antimicrobial stewardship and reduce preventable deaths from BSIs. To support the successful implementation of rapid AST (rAST) in hospital settings, a rAST method that is affordable, is sustainable and offers comprehensive AMR detection is needed.Aim. To evaluate a scattered light-integrated collection (SLIC) device against standard of care (SOC) to determine whether SLIC could accelerate the current TATs with actionable, accurate rAST results for Gram-negative BSIs.Methods. Positive blood cultures from a tertiary referral hospital were studied prospectively. Flagged positive Gram-negative blood cultures were confirmed by Gram staining and analysed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Vitek 2, disc diffusion (ceftriaxone susceptibility only) and an SLIC device. Susceptibility to a panel of five antibiotics, as defined by European Committee on Antimicrobial Susceptibility Testing breakpoints, was examined using SLIC.Results. A total of 505 bacterial-antimicrobial combinations were analysed. A categorical agreement of 95.5 % (482/505) was achieved between SLIC and SOC. The 23 discrepancies that occurred were further investigated by the broth microdilution method, with 10 AST results in agreement with SLIC and 13 in agreement with SOC. The mean time for AST was 10.53±0.46 h and 1.94±0.02 h for Vitek 2 and SLIC, respectively. SLIC saved 23.96±1.47 h from positive blood culture to AST result.Conclusion. SLIC has the capacity to provide accurate AST 1 day earlier from flagged positive blood cultures than SOC. This significant time saving could accelerate time to optimal antimicrobial therapy, improving antimicrobial stewardship and management of BSIs.

Asunto(s)

Programas de Optimización del Uso de los Antimicrobianos , Sepsis , Humanos , Cultivo de Sangre , Estudios Retrospectivos , Bacterias Gramnegativas , Antibacterianos/farmacología

RESUMEN

We developed a novel culture-based test, the Rapid CAZ/AVI NP test, for rapid identification of ceftazidime/avibactam susceptibility/resistance in Enterobacterales. This test is based on glucose metabolization upon bacterial growth in the presence of a defined concentration of ceftazidime/avibactam (128/53 µg/mL). Bacterial growth is visually detectable by a red to yellow color change of red phenol, a pH indicator. A total of 101 well characterized enterobacterial isolates were used to evaluate the test performance. This test showed positive percent agreement of 100% and negative percent agreement of 98.5% with overall percent agreement of 99%, by comparison with the MIC gradient strip test (Etest) taken as the reference standard method. The Rapid CAZ/AVI NP test had only 1.5% major errors and 0% extremely major errors. This test is rapid (result within 2 hours 45 minutes), reliable, affordable, easily interpretable, and easy to implement in clinical microbiology laboratories without requiring any specific equipment.

Asunto(s)

Compuestos de Azabiciclo , Ceftazidima , Gammaproteobacteria , Ceftazidima/farmacología , Enterobacteriaceae , Laboratorios

RESUMEN

IMPORTANCE: Our study addresses a significant issue in the medical and scientific community-the delayed administration of appropriate antimicrobial treatments due to the time-consuming process of phenotypic susceptibility data collection in gram-negative bloodstream infections. Our research indicates that a multiplex PCR rapid diagnostic test (RDT) significantly outperformed two clinical scoring tools in predicting ceftriaxone susceptibility. Multiplex PCR also led to reduced instances of undertreatment with ceftriaxone and minimized overtreatment with carbapenems. Furthermore, multiplex PCR demonstrated high sensitivity and specificity in predicting ceftriaxone susceptibility. The results of our study underscore the potential RDTs to reduce the time to appropriate antimicrobial therapy, leading to improved patient outcomes and reduced healthcare costs.

Asunto(s)

Antiinfecciosos , Bacteriemia , Sepsis , Humanos , Prueba de Diagnóstico Rápido , Ceftriaxona/uso terapéutico , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Antiinfecciosos/uso terapéutico , Sepsis/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética