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1.
Nat Commun ; 11(1): 1072, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32102999

RESUMO

Phosphocreatine (PCr) plays a vital role in neuron and myocyte energy homeostasis. Currently, there are no routine diagnostic tests to noninvasively map PCr distribution with clinically relevant spatial resolution and scan time. Here, we demonstrate that artificial neural network-based chemical exchange saturation transfer (ANNCEST) can be used to rapidly quantify PCr concentration with robust immunity to commonly seen MRI interferences. High-quality PCr mapping of human skeletal muscle, as well as the information of exchange rate, magnetic field and radio-frequency transmission inhomogeneities, can be obtained within 1.5 min on a 3 T standard MRI scanner using ANNCEST. For further validation, we apply ANNCEST to measure the PCr concentrations in exercised skeletal muscle. The ANNCEST outcomes strongly correlate with those from 31P magnetic resonance spectroscopy (R = 0.813, p < 0.001, t test). These results suggest that ANNCEST has potential as a cost-effective and widely available method for measuring PCr and diagnosing related diseases.


Assuntos
Imagem por Ressonância Magnética/métodos , Músculo Esquelético/fisiologia , Redes Neurais de Computação , Fosfocreatina/análise , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Humanos , Doenças Musculares/diagnóstico
2.
J Med Microbiol ; 69(2): 244-248, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31958047

RESUMO

Introduction. Mycoplasma genitalium is a sexually transmitted organism with high levels of resistance to the recommended first-line therapy, azithromycin. The ResistancePlus MG test concurrently detects M. genitalium, and the presence of macrolide-resistance mutations (MRM). European, UK and Australian guidelines recommend a diagnostic test that reports MRM to optimize treatment through resistance-guided therapy. Hence, for samples collected for use on other platforms, reflex testing using the ResistancePlus MG test would be beneficial.Aim. To validate the ResistancePlus MG assay using samples collected in Aptima buffer for testing on the Hologic Panther.Methodology. Positive (n=99) and negative (n=229) clinical samples collected in Aptima buffer were extracted on the MagNA Pure 96 (Roche Diagnostics), and tested with the ResistancePlus MG test on the LightCycler 480 II (Roche Diagnostics). Results were compared to matched samples collected using standard sample collection (urine or swab resuspended in PBS), with positive percent agreement (PPA), negative percent agreement (NPA) and Cohen's Kappa statistic.Results. The ResistancePlus MG test had high performance with a 200 µl input volume (PPA/NPA for M. genitalium detection, 92.9 % [95 % confidence interval (CI): 85.5-96.9]/100 % [95 % CI: 97.9-100], MRM detection, 96.9 % [95 % CI: 88.2-99.5]/85.7 % [95 % CI: 66.4-95.3]) and for 1 ml input volume (PPA/NPA for M. genitalium detection, 95.9%/96.6%, MRM detection, 98.4%/90.3%). Samples remained positive after storage at room temperature beyond the manufacturer-recommended storage of <60 days (mean storage time for 1 ml extraction: 129 days).Conclusion. Samples collected using Aptima collection kits are suitable for reflex testing using the ResistancePlus MG test, allowing detection of macrolide resistance.


Assuntos
Antibacterianos/farmacologia , Testes Diagnósticos de Rotina/métodos , Farmacorresistência Bacteriana , Infecções por Mycoplasma/microbiologia , Mycoplasma genitalium/efeitos dos fármacos , Mycoplasma genitalium/isolamento & purificação , Austrália , Testes Diagnósticos de Rotina/instrumentação , Humanos , Macrolídeos/farmacologia , Infecções por Mycoplasma/diagnóstico , Mycoplasma genitalium/genética , Kit de Reagentes para Diagnóstico , Manejo de Espécimes
4.
Ann Biol Clin (Paris) ; 77(6): 693-696, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31859648

RESUMO

Several hyperthyroidism misdiagnoses cases have been recently described due to biotin intake. Biotin used in immuno-analysis assays which rely on biotin/streptavidin binding properties. In these assays, high plasmatic biotin levels can lead to major analytical interferences resulting in falsely higher (competition tests) or falsely reduced determinations (for sandwiches assays). We performed a simulation test of biotin intake with patient's samples. We studied the effect of biotin on cardiac troponin I and total vitamin D (D2+D3) assays that are using biotin-streptavidin binding on Dimension EXL®. Increasing doses of biotin were added (28 samples for each parameter) before the assays. The results evidenced a significant negative interference of biotin on cardiac troponin I determinations for concentrations of 100 ng/mL and above, with a total loss of signal for higher biotin additions. Such interference may lead to inappropriate therapeutic decisions. Positive interferences were observed on total vitamin D (D2+D3) with less impact for therapeutic decisions.


Assuntos
Ligação Competitiva , Biotina/metabolismo , Testes Diagnósticos de Rotina , Hipertireoidismo/diagnóstico , Estreptavidina/metabolismo , Troponina I/análise , Vitamina D/análise , Adulto , Artefatos , Biotina/administração & dosagem , Biotina/efeitos adversos , Colecalciferol/análise , Colecalciferol/sangue , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico , Erros de Diagnóstico , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/normas , Ergocalciferóis/análise , Ergocalciferóis/sangue , Humanos , Hipertireoidismo/sangue , Imunoensaio/instrumentação , Imunoensaio/métodos , Miocárdio/química , Miocárdio/metabolismo , Troponina I/sangue , Troponina I/metabolismo , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico
5.
Vet Ital ; 55(3): 261-267, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31599551

RESUMO

Six horses were challenged experimentally with a strain of Burkholderia pseudomallei isolated from a fatal case of the infection in a dromedary camel years earlier in the Emirate of Dubai. Three horses were inoculated subcutaneously and in 3 the bacterium was administered by the oral route. Four of the horses became serologically positive based on reactions to one or more of the OIE described tests for glanders. B. pseudomallei was re-isolated from the 4 serological positive horses. Only one of the subcutaneously infected horses, developed fever for 3 days. The white blood cell values and the neutrophil counts were also elevated. The study confirmed that existing serological test for diagnosing glanders cannot differentiate between glanders and melioidosis in horses.


Assuntos
Burkholderia pseudomallei/fisiologia , Testes Diagnósticos de Rotina/veterinária , Doenças dos Cavalos/diagnóstico , Melioidose/veterinária , Animais , Anticorpos Antibacterianos/sangue , Testes Diagnósticos de Rotina/instrumentação , Feminino , Mormo/diagnóstico , Doenças dos Cavalos/microbiologia , Cavalos , Masculino , Melioidose/diagnóstico , Melioidose/microbiologia , Emirados Árabes Unidos
6.
PLoS Negl Trop Dis ; 13(8): e0007446, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31369558

RESUMO

BACKGROUND: Because the success of deworming programs targeting soil-transmitted helminths (STHs) is evaluated through the periodically assessment of prevalence and infection intensities, the use of the correct diagnostic method is of utmost importance. The STH community has recently published for each phase of a deworming program the minimal criteria that a potential diagnostic method needs to meet, the so-called target product profiles (TPPs). METHODOLOGY: We compared the diagnostic performance of a single Kato-Katz (reference method) with that of other microscopy-based methods (duplicate Kato-Katz, Mini-FLOTAC and FECPAKG2) and one DNA-based method (qPCR) for the detection and quantification of STH infections in three drug efficacy trials in Ethiopia, Lao PDR, and Tanzania. Furthermore, we evaluated a selection of minimal diagnostic criteria of the TPPs. PRINCIPAL FINDINGS: All diagnostic methods showed a clinical sensitivity of ≥90% for all STH infections of moderate-to-heavy intensities. For infections of very low intensity, only qPCR resulted in a sensitivity that was superior to a single Kato-Katz for all STHs. Compared to the reference method, both Mini-FLOTAC and FECPAKG2 resulted in significantly lower fecal egg counts for some STHs, leading to a substantial underestimation of the infection intensity. For qPCR, there was a positive significant correlation between the egg counts of a single Kato-Katz and the DNA concentration. CONCLUSIONS/SIGNIFICANCE: Our results indicate that the diagnostic performance of a single Kato-Katz is underestimated by the community and that diagnostic specific thresholds to classify intensity of infection are warranted for Mini-FLOTAC, FECPAKG2 and qPCR. When we strictly apply the TPPs, Kato-Katz is the only microscopy-based method that meets the minimal diagnostic criteria for application in the planning, monitoring and evaluation phase of an STH program. qPCR is the only method that could be considered in the phase that aims to seek confirmation for cessation of program. TRIAL REGISTRATION: ClinicalTrials.gov NCT03465488.


Assuntos
Testes Diagnósticos de Rotina/métodos , Helmintíase/parasitologia , Helmintíase/transmissão , Helmintos/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Solo/parasitologia , Adolescente , Animais , Brasil , Criança , Testes Diagnósticos de Rotina/instrumentação , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Helmintíase/diagnóstico , Helmintíase/epidemiologia , Helmintos/genética , Humanos , Laos/epidemiologia , Masculino , Microscopia , Técnicas de Diagnóstico Molecular/instrumentação , Contagem de Ovos de Parasitas/métodos , Prevalência , Sensibilidade e Especificidade , Tanzânia/epidemiologia , Organização Mundial da Saúde
7.
Parasitol Int ; 73: 101941, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31442664

RESUMO

Polymerase chain reaction (PCR) is an essential diagnostic method for highly sensitive detection of Plasmodium-infected erythrocytes in patients with malaria. This study compared the performance of filter papers used for the preparation of dried blood spots (DBS) in detecting Plasmodium by PCR. Whole blood spiked with P. falciparum-infected erythrocytes to obtain samples with various levels of parasitemia were applied to Whatman 3MM Chr papers, FTA Cards, or FTA Elute Cards to prepare the DBS. DNA was purified from the DBS using a DNA purification kit and used as the template for nested PCR. In probit analysis, the estimated limit of detection (LoD) was 5.5 parasites/µL blood for Whatman 3MM Chr papers and FTA Cards and 1.6 parasites/µL blood for the FTA Elute Card. This result suggested that the DBS prepared on an FTA Elute Card yield the best template DNA for subsequent high-sensitivity PCR-based detection of P. falciparum-infected erythrocytes. This finding can help improve the accuracy of malarial diagnostic tests.


Assuntos
DNA de Protozoário/análise , Teste em Amostras de Sangue Seco/métodos , Malária Falciparum/diagnóstico , Plasmodium falciparum/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 18S/análise , Testes Diagnósticos de Rotina/instrumentação , Humanos , Limite de Detecção
8.
Diagn Microbiol Infect Dis ; 95(3): 114841, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422873

RESUMO

OBJECTIVES: To compare the performance and time-to-result (TTR) for antimicrobial susceptibility testing (AST) of positive blood cultures (PBC) using the Accelerate Pheno™ system (AXDX) and both a direct VITEK® 2 card inoculation workflow (DV2) and traditional FDA-approved VITEK® 2 workflow using subcultured isolates (V2). METHODS: Patient samples with monomicrobial Gram-negative rod bacteremia were tested on AXDX and DV2 in tandem and compared to V2 AST results. Categorical agreement (CA) errors were adjudicated using broth microdilution. Instrumentation times and AST TTR were compared. RESULTS: AXDX and DV2 had a CA of 93.4% and 97.4%, respectively, compared to V2. Postadjudication, AXDX, DV2, and V2 had CA of 94.7%, 95.7%, and 96.5%, respectively. Instrument run times were 6.6 h, 9.4 h, and 9.2 h, and AST TTR were 8.9 h, 12.9 h and 35.5 h, respectively. CONCLUSIONS: AXDX and DV2 ASTs are fast and reliable, which may have significant antimicrobial stewardship implications.


Assuntos
Hemocultura , Testes Diagnósticos de Rotina/métodos , Testes de Sensibilidade Microbiana/métodos , Gestão de Antimicrobianos , Bacteriemia/microbiologia , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/normas , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Testes de Sensibilidade Microbiana/instrumentação , Testes de Sensibilidade Microbiana/normas , Estudos Prospectivos , Fatores de Tempo , Fluxo de Trabalho , beta-Lactamases/biossíntese
9.
BMC Med ; 17(1): 103, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31146732

RESUMO

BACKGROUND: Accurate and timely diagnosis of malaria is essential for disease management and surveillance. Thin and thick blood smear microscopy and malaria rapid diagnostic tests (RDTs) are standard malaria diagnostics, but both methods have limitations. The novel automated hematology analyzer XN-30 provides standard complete blood counts (CBC) as well as quantification of malaria parasitemia at the price of a CBC. This study assessed the accuracy of XN-30 for malaria detection in a controlled human malaria infection (CHMI) study and a phase 3 diagnostic accuracy study in Burkina Faso. METHODS: Sixteen healthy, malaria-naive CHMI participants were challenged with five Plasmodium falciparum-infected mosquitoes. Blood was sampled daily for XN-30, blood smear microscopy, and malaria qPCR. The accuracy study included patients aged > 3 months presenting with acute febrile illness. XN-30, microscopy, and rapid diagnostic tests (HRP-2/pLDH) were performed on site; qPCR was done in retrospect. The malaria reference standard was microscopy, and results were corrected for sub-microscopic cases. RESULTS: All CHMI participants became parasitemic by qPCR and XN-30 with a strong correlation for parasite density (R2 = 0.91; p < .0001). The XN-30 accurately monitored treatment and allowed detection of recrudescence. Out of 908 patients in the accuracy study, 241 had microscopic malaria (density 24-491,802 parasites/µL). The sensitivity and specificity of XN-30 compared to microscopy were 98.7% and 99.4% (PPV = 98.7%, NPV = 99.4%). Results were corrected for qPCR-confirmed sub-microscopic cases. Three microscopy-confirmed cases were not detected by XN-30. However, XN-30 detected 19/134 (14.2%) qPCR-confirmed cases missed by microscopy. Among qPCR-confirmed cases, XN-30 had a higher sensitivity (70.9% versus 66.4%; p = .0009) and similar specificity (99.6% versus 100%; p = .5) as microscopy. The accuracy of XN-30 for microscopic malaria was equal to or higher than HRP-2 and pLDH RDTs, respectively. CONCLUSIONS: The XN-30 is a novel, automated hematology analyzer that combines standard hemocytometry with rapid, objective, and robust malaria detection and quantification, ensuring prompt treatment of malaria and malaria anemia and follow-up of treatment response. TRIAL REGISTRATION: Both trials were registered on clinicaltrials.gov with respective identifiers NCT02836002 (CHMI trial) and NCT02669823 (diagnostic accuracy study).


Assuntos
Testes Diagnósticos de Rotina , Hematologia/instrumentação , Malária/diagnóstico , Adolescente , Adulto , Animais , Antígenos de Protozoários/análise , Antígenos de Protozoários/sangue , Automação Laboratorial , Burkina Faso , Criança , Pré-Escolar , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Método Duplo-Cego , Feminino , Hematologia/métodos , Humanos , Lactente , Recém-Nascido , Malária/sangue , Malária Falciparum/sangue , Malária Falciparum/diagnóstico , Masculino , Pessoa de Meia-Idade , Parasitemia/sangue , Parasitemia/diagnóstico , Plasmodium falciparum/imunologia , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
10.
PLoS Negl Trop Dis ; 13(5): e0007303, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31067228

RESUMO

BACKGROUND: Typhoid fevers are infections caused by the bacteria Salmonella enterica serovar Typhi (Salmonella Typhi) and Paratyphi A, B and C (Salmonella Paratyphi). Approximately 17.8 million incident cases of typhoid fever occur annually, and incidence is highest in children. The accuracy of current diagnostic tests of typhoid fever is poorly understood. We aimed to determine the comparative accuracy of available tests for the pediatric population. METHODS: We first conducted a systematic literature review to identify studies that compared diagnostic tests for typhoid fever in children (aged ≤15 years) to blood culture results. We applied a Bayesian latent-class extension to a network meta-analysis model. We modelled known diagnostic properties of bone marrow culture and the relationship between bone marrow and blood culture as informative priors in a Bayesian framework. We tested sensitivities for the proportion of negative blood samples that were false as well as bone marrow sensitivity and specificity. RESULTS: We found 510 comparisons from 196 studies and 57 specific to the pediatric population. IgM-based tests outperformed their IgG-based counterparts for ELISA and Typhidot tests. The lateral flow IgG test performed comparatively well with 92% sensitivity (72% to 98% across scenario analyses) and 94% specificity. The most sensitive test of those investigated for the South Asian pediatric population was the Reverse Passive Hemagglutination Assay with 99% sensitivity (98% - 100% across scenario analyses). Adding a Widal slide test to other typhoid diagnostics did not substantially improve diagnostic performance beyond the single test alone, however, a lateral flow-based IgG rapid test combined with the typhoid/paratyphoid (TPT) assay yielded improvements in sensitivity without substantial declines in specificity and was the best performing combination test in this setting. CONCLUSION: In the pediatric population, lateral-flow IgG, TPT and Reverse Passive Hemagglutination tests had high diagnostic accuracy compared to other diagnostics. Combinations of tests may provide a feasible option to increase diagnostic sensitivity. South Asia has the most informed set of data on typhoid diagnostic testing accuracy, and the evidence base in other important regions needs to be expanded.


Assuntos
Testes Diagnósticos de Rotina/métodos , Febre Tifoide/diagnóstico , Adolescente , Anticorpos Antibacterianos/sangue , Teorema de Bayes , Criança , Pré-Escolar , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/normas , Feminino , Humanos , Masculino , Kit de Reagentes para Diagnóstico/normas , Salmonella typhi/genética , Salmonella typhi/isolamento & purificação , Sensibilidade e Especificidade , Febre Tifoide/sangue , Febre Tifoide/microbiologia , Adulto Jovem
11.
Transbound Emerg Dis ; 66(4): 1789-1795, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077564

RESUMO

Foot-and-mouth disease (FMD) is a highly contagious disease of livestock that requires rapid control. Early detection is critical but transportation of samples to laboratory delays testing. Sensitive and specific field-deployable assays are therefore desirable. Real-time reverse transcription polymerase chain reaction (RRT-PCR) and RRT-loop-mediated isothermal amplification assays for FMDV on portable platforms have been described but none of these are handheld. In this report, we have evaluated a handheld Biomeme two3™ Real-Time PCR Thermocycler (two3) as a field-deployable platform for FMDV RRT-PCR targeting the 3D gene segment. Two3's performance was compared with the laboratory-based reference assay on the ABI7500 platform. RNA extraction using a rapid Biomeme proprietary sample prep technology (M1) was compared with MagMax RNA extraction. Two3 successfully detected FMDV isolates for six serotypes (O, A, Asia 1, SAT 1, 2 and 3). Serotype C was excluded since it has not been detected in the field since 2004. The limits of detection for serial 10-fold dilutions of cell culture isolates were equal or one log different between two3 and ABI7500. Furthermore, two3 detected FMDV RNA in multiple sample types including serum, vesicular fluid, tissue suspensions, oral fluid, oral and nasal swabs. Two3 also detected FMDV RNA directly in vesicular fluid and other samples without prior RNA extraction. Comparison of the time to first detection of a positive result in serial samples in MagMax RNA extraction/ABI7500 (MgMx/ABI) system vs. M1 RNA extraction/Two3 system revealed similar or slightly better analytical sensitivity for the MgMx/ABI system. Overall, RNA extraction by M1 yielded good results and FMDV RNA detection on two3 was not significantly different from the ABI7500. Therefore, two3 could potentially enable sensitive penside detection of FMDV within an hour using M1-extracted RNA or direct testing of vesicular fluid and swabs without RNA extraction thereby ensuring prompt implementation of appropriate control measures.


Assuntos
Doenças dos Bovinos/diagnóstico , Vírus da Febre Aftosa/isolamento & purificação , Febre Aftosa/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Doenças dos Ovinos/diagnóstico , Doenças dos Suínos/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/virologia , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/veterinária , Febre Aftosa/virologia , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Sorogrupo , Ovinos , Doenças dos Ovinos/virologia , Suínos , Doenças dos Suínos/virologia
12.
J Microbiol Immunol Infect ; 52(5): 760-768, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31085115

RESUMO

BACKGROUND/PURPOSE: Early recognition of causative pathogens is critical for the appropriate management of central nervous system infection and improved outcomes. The BioFire® FilmArray® Meningitis/Encephalitis Panel (BioFire® ME Panel, BioFire Diagnostics) is the first U.S. Food and Drug Administration (FDA)-approved multiplex PCR assay that allows the rapid detection of 14 pathogens, including bacteria (n = 6), viruses (n = 7), and fungi (n = 1), from cerebrospinal fluid (CSF). The performance of the panel is expected to be dependent on the epidemiology of M/E in different geographical regions. METHODS: In this preliminary study, we used the BioFire® ME Panel in 42 subjects who presented to the emergency department with symptoms of M/E in our hospital. The results were compared to conventional culture, antigen detection, PCR, and various laboratory findings. RESULTS: The panel detected six positive samples, of which five were viral and one bacterial. We observed an overall agreement rate of 88% between the BioFire® ME Panel results and the conventional methods. There were no false-positive findings, but five discordant results were observed for enterovirus, herpes simplex virus type 1, Escherichia coli, and Cryptococcus species. CONCLUSIONS: The BioFire® ME Panel performed equivalently to the traditional PCR methods for virus detection, and better than bacterial cultures. This revolutionary system represents a paradigm shift in the diagnosis of M/E and may aid in the rapid identification of community-acquired M/E. However, the usefulness of this tool is limited in regions with a high prevalence of infectious M/E caused by microorganisms not included in the panel.


Assuntos
Testes Diagnósticos de Rotina/métodos , Encefalite/diagnóstico , Meningite/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Adulto , Idoso , Bactérias/isolamento & purificação , Testes Diagnósticos de Rotina/instrumentação , Serviço Hospitalar de Emergência , Feminino , Fungos/isolamento & purificação , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Taiwan , Vírus/isolamento & purificação
13.
Clin Microbiol Infect ; 25(9): 1086-1095, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31039443

RESUMO

BACKGROUND: Microbial whole genome sequencing (WGS) has many advantages over standard microbiological methods. However, it is not yet widely implemented in routine hospital diagnostics due to notable challenges. OBJECTIVES: The aim was to extract managerial, financial and clinical criteria supporting the decision to implement WGS in routine diagnostic microbiology, across different operational models of implementation in the hospital setting. METHODS: This was a systematic review of literature identified through PubMed and Web of Science. English literature studies discussing the applications of microbial WGS without limitation on publication date were eligible. A narrative approach for categorization and synthesis of the sources identified was adopted. RESULTS: A total of 98 sources were included. Four main alternative operational models for incorporating WGS in clinical microbiology laboratories were identified: full in-house sequencing and analysis, full outsourcing of sequencing and analysis and two hybrid models combining in-house/outsourcing of the sequencing and analysis components. Six main criteria (and multiple related sub-criteria) for WGS implementation emerged from our review and included cost (e.g. the availability of resources for capital and operational investment); manpower (e.g. the ability to provide training programmes or recruit trained personnel), laboratory infrastructure (e.g. the availability of supplies and consumables or sequencing platforms), bioinformatics requirements (e.g. the availability of valid analysis tools); computational infrastructure (e.g. the availability of storage space or data safety arrangements); and quality control (e.g. the existence of standardized procedures). CONCLUSIONS: The decision to incorporate WGS in routine diagnostics involves multiple, sometimes competing, criteria and sub-criteria. Mapping these criteria systematically is an essential stage in developing policies for adoption of this technology, e.g. using a multicriteria decision tool. Future research that will prioritize criteria and sub-criteria that were identified in our review in the context of operational models will inform decision-making at clinical and managerial levels with respect to effective implementation of WGS for routine use. Beyond WGS, similar decision-making challenges are expected with respect to future integration of clinical metagenomics.


Assuntos
Doenças Transmissíveis/diagnóstico , Testes Diagnósticos de Rotina/normas , Técnicas Microbiológicas/normas , Sequenciamento Completo do Genoma/normas , Técnicas de Apoio para a Decisão , Testes Diagnósticos de Rotina/economia , Testes Diagnósticos de Rotina/instrumentação , Humanos , Metagenômica , Técnicas Microbiológicas/economia , Técnicas Microbiológicas/instrumentação , Controle de Qualidade , Sequenciamento Completo do Genoma/economia , Sequenciamento Completo do Genoma/instrumentação
14.
EBioMedicine ; 42: 504-510, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30885726

RESUMO

BACKGROUND: Iron deficiency (ID) and anaemia are major health concerns, particularly in young children. Screening for ID based on haemoglobin (Hb) concentration alone has been shown to lack sensitivity and specificity. The American Academy of Pediatrics (AAP) recommends soluble transferrin receptor (sTfR) as a promising approach to screen for iron deficiency. However, in most settings, assessment of iron status requires access to centralized laboratories. There is an urgent need for rapid, sensitive, and affordable diagnostics for sTfR at the point-of-care. METHODS: An immunochromatographic assay-based point-of-care screening device was developed for rapid quantification of sTfR from a drop of serum within a few minutes. Performance optimization of the assay was done in sTfR-spiked buffer and commercially available sTfR calibrator, followed by a small-scale proof-of-concept validation with archived serum samples. FINDINGS: On preliminary testing with archived serum samples and comparison with Ramco ELISA, a correlation of 0.93 (P < 0.0001) was observed, demonstrating its potential for point-of-care assessment of iron status. INTERPRETATION: The analytical performance of the point-of-care sTfR screening device indicates the potential for application in home-use test kits and field settings, especially in low- and middle-income settings. An added advantage of sTfR quantification in combination with our previously reported serum ferritin diagnostics is in integration of Cook's equation as a quantitative and minimally-invasive indicator of total body iron stores. FUND: Thrasher Research Fund (Early Career Award #13379), NIH R03 EB 023190, NSF grant #1343058, and Nutrition International (project #10-8007-CORNE-01).


Assuntos
Anemia Ferropriva/sangue , Anemia Ferropriva/diagnóstico , Testes Imediatos , Receptores da Transferrina/sangue , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Humanos , Nanotecnologia , Fitas Reagentes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Clin Lab ; 65(1)2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30775889

RESUMO

BACKGROUND: Urinalysis based on microbiological culture and manual microscopy requires expertise and is labor intensive. Automated screening could save time and improve patient management in clinical settings. METHODS: We evaluated the fully automated cobas u 701 analyzer for identifying infection-negative urine samples using 2,046 anonymized samples from a routine pathology laboratory. Samples containing ≥ 40 white blood cells (WBC)/µL and/or ≥ 100 bacteria/µL were considered positive. For microbiological cultures: pure growth of ≥ 108 colony-forming units (cfu)/L was considered significant; > 107 cfu/L was considered significant for pregnant women, children < 12 years, immune-compromised/critical care patients or patients with > 100 WBC/µL. RESULTS: The cobas u 701 analyzer identified 1,346 positive samples, giving a 65.7% culture rate. Sensitivity and negative predictive value were high (> 99%). Most replicates were within two standard deviations of the original measurement. CONCLUSIONS: The cobas u 701 analyzer is an effective screening tool for routine urinalysis and demonstrates rapid turnaround times, thus benefiting patients and clinicians.


Assuntos
Infecções Bacterianas/urina , Programas de Rastreamento/métodos , Microscopia/métodos , Urinálise/métodos , Automação , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Carga Bacteriana , Criança , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Feminino , Humanos , Contagem de Leucócitos , Programas de Rastreamento/instrumentação , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Urina/citologia , Urina/microbiologia
17.
Acta Trop ; 193: 7-11, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30768978

RESUMO

Microscopic examination of blood smears is the standard method for malaria diagnosis but is labor-intensive and requires expert staff. CellaVision DM96 (CellaVision, Lund, Sweden) is a digital hematology analyzer available for advanced morphological analysis of blood films including intracellular parasites. Here, we evaluated the CellaVision DM96 Advanced RBC Application for malaria detection in stained peripheral blood (PB) smears. Two hundred and twenty thin PB smear slides (84 P. vivax, 14 P. falciparum, 122 negative controls) were stained with Wright-Giemsa using automated slidemaker/strainers of Beckman Coulter hematology systems (LH780, Beckman Coulter Inc., Miami, FL). The slides were automatically analyzed by CellaVision, and images were manually reviewed by experts. The results of automatic and manual detection by CellaVision were compared to those of microscopic examination. The sensitivity and specificity of automatic detection by CellaVision were 23.5% (23/98) and 81.1% (99/122), respectively. When CellaVision images were manually reviewed, the sensitivity and specificity increased to 65.3% (64/98) and 90.2% (110/122), respectively. The detection of P. falciparum showed the highest sensitivity by both the automated (33.3%) and the manual (85.7%) method. CellaVision misinterpreted malaria parasites as Howell-Jolly bodies in 57.1%, as Pappenheimer bodies in 84.7%, and as basophilic stipplings in 75.5% of the slides. Malaria diagnosis using CellaVision DM96 requires further improvements. Manual review improves CellaVision performance, but confirmation by conventional microscopy remains essential.


Assuntos
Testes Diagnósticos de Rotina/instrumentação , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Plasmodium falciparum , Plasmodium vivax , Humanos , Malária Falciparum/sangue , Malária Vivax/sangue , Microscopia , Sensibilidade e Especificidade
18.
Transbound Emerg Dis ; 66(1): 144-155, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30103262

RESUMO

Differential diagnosis of diseases that share common clinical signs typically requires the performance of multiple independent diagnostic tests to confirm diagnosis. Diagnostic tests that can detect and discriminate between multiple differential pathogens in a single reaction may expedite, reduce costs, and streamline the diagnostic testing workflow. Livestock haemorrhagic diseases like classical swine fever (CSF), African swine fever (ASF), and vesicular diseases, such as foot-and-mouth disease (FMD), vesicular stomatitis (VS), and swine vesicular disease (SVD) can have an enormous impact on the livestock industry and economy of countries that were previously free of the diseases. Thus, rapid diagnosis of these diseases is critical for disease control. Here, we describe the development and initial laboratory validation of a novel fully automated user-developed assay for simultaneous detection and differentiation of multiple viruses of veterinary importance in a single reaction with minimal user-intervention. The user only performs sample loading, placement of consumables and reagents, selection and initiation of assay while all other processes (i.e., nucleic acid extraction, multiplex RT-PCR, reverse dot blot detection and result reporting) are performed fully automated. The current assay has a turn-around time of approximately 6 hr and can simultaneously process up to 24 samples. The automated assay accurately and specifically detected 37 laboratory amplified strains of the five target viruses, including all seven serotypes of FMD virus, three genotypes of CSF virus, and two serotypes of VS virus. The assay also detected targeted viruses in a variety of clinical samples collected from infected animals, such as oral fluid, oral swab, nasal swab, whole blood, serum, as well as tonsil, spleen, kidney, and ileum. No cross-reactivity was observed with 15 nontarget viruses that affect livestock and samples from clinically healthy animals. To our knowledge, this is the first fully automated and integrated assay for simultaneous detection of multiple high consequence veterinary pathogens.


Assuntos
Testes Diagnósticos de Rotina/veterinária , Monitoramento Epidemiológico/veterinária , Genoma Viral , Immunoblotting/veterinária , Microfluídica/métodos , Reação em Cadeia da Polimerase/veterinária , Febre Suína Africana/diagnóstico , Animais , Peste Suína Clássica/diagnóstico , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Febre Aftosa/diagnóstico , Immunoblotting/métodos , Gado , Microfluídica/instrumentação , Reação em Cadeia da Polimerase/métodos , Suínos , Doença Vesicular Suína/diagnóstico , Estomatite Vesicular/diagnóstico
20.
Diagn Microbiol Infect Dis ; 93(1): 44-53, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30279025

RESUMO

Galactomannan (GM), 1,3-ß-D-glucan (BDG) and aspergillus-lateral flow device (LFD) are recognized as diagnostic tools for invasive aspergillosis (IA). The combined performance of these assays, however, is inconsistent in various studies. We undertook a meta-analysis of 13 studies involving 1513 patients to evaluate the utility of GM in combination with BDG or LFD for diagnosing IA. The pooled SEN, SPE, PLR, NLR and diagnostic odds ratio (DOR) were calculated and constructed to summarize the overall combined performance. Combining both positive results of GM and BDG assays leaded to the pooled SEN 0.49 (95%CI 0.27-0.72), SPE 0.98 (95%CI 0.94-1.00), PLR 31.68 (95%CI 5.36-187.37), NLR 0.52 (95%CI 0.32-0.84) and DOR 61.23 (95%CI 6.96-538.90). Comparing with GM and BDG assays, both positive results of GM and LFD leaded to high SEN, similar SPE, low PLR and NLR. At least one positive result of GM or LFD conferred great SEN 0.93 and low NLR 0.08. Both positive results of GM and BDG or LFD assay were in favor of confirming the existence of IA. And both negative results of GM and LFD were beneficial to rule out IA. Further studies with sufficient sample size should focus on the diagnostic performance and cost-effectiveness of these combined tests in clinical setting.


Assuntos
Antígenos de Fungos/análise , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Aspergilose Pulmonar Invasiva/diagnóstico , Mananas/análise , Técnicas Microbiológicas/instrumentação , beta-Glucanas/análise , Aspergillus/imunologia , Aspergillus/isolamento & purificação , Humanos , Imunoensaio/instrumentação , Técnicas Microbiológicas/normas , Razão de Chances , Sensibilidade e Especificidade
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