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1.
Vet Parasitol ; 277: 109017, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31901535

RESUMO

Cystic echinococcosis represents a significant problem in human and animal health and constitutes one of the most severe Neglected Tropical Diseases prioritized by the World Health Organization. The etiological agent is the complex Echinococcus granulosus sensu lato (s. l.), composed of several species/genotypes. Diagnosis in the definitive host and molecular epidemiology studies are important points for cystic echinococcosis control. Here we developed a new copro-LAMP assay, LAMP EGSL, for diagnosis in the definitive host for simultaneous detection of Echinococcus granulosus sensu stricto (s. s.), Echinococcus ortleppi, and Echinococcus canadensis species. Also, the analytical sensitivity, specificity and plausibility of performance in a rural context of a previously reported species-specific LAMP reaction, was evaluated. Both reactions showed high analytical sensitivity values (10 fg-100 fg DNA) and did not show cross reaction with DNA from host or other helminthic parasites. LAMP EGSL was performed with samples from an endemic area. In addition, the alkaline hydrolysis of one E. granulosus s. s. adult parasite followed by specific LAMP to E. granulosus s. s. was performed in a laboratory with low resources from another cystic echinococcosis endemic area. The results obtained suggest that LAMP EGSL represents a potential tool for canine diagnosis that could be useful for cystic echinococcosis control programs. In addition, we showed that LAMP reaction for E. granulous s. s., E. ortleppi and E. canadensis specific detection, could be useful for molecular epidemiology studies applicable to the definitive host. Both reactions were performed in endemic, rural areas without sophisticated equipment.


Assuntos
Testes Diagnósticos de Rotina/métodos , Doenças do Cão/diagnóstico , Equinococose/veterinária , Echinococcus granulosus , Parasitologia/métodos , Animais , Doenças do Cão/parasitologia , Cães , Equinococose/diagnóstico , Equinococose/parasitologia , Sensibilidade e Especificidade , Especificidade da Espécie
2.
MMWR Morb Mortal Wkly Rep ; 69(3): 63-66, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31971928

RESUMO

Since 2014, the recommended laboratory testing algorithm for diagnosing human immunodeficiency virus (HIV) infection has included a supplemental HIV-1/HIV-2 differentiation test to confirm infection type on the basis of the presence of type-specific antibodies (1). Correctly identifying HIV-1 and HIV-2 infections is vital because their epidemiology and clinical management differ. To describe the percentage of diagnoses for which an HIV-1/HIV-2 differentiation test result was reported and to categorize HIV type based on laboratory test results, 2010-2017 data from CDC's National HIV Surveillance System (NHSS) were analyzed. During 2010-2017, a substantial increase in the number of HIV-1/HIV-2 differentiation test results were reported to NHSS, consistent with implementation of the HIV laboratory-based testing algorithm recommended in 2014. However, >99.9% of all HIV infections identified in the United States were categorized as HIV-1, and the number of HIV-2 diagnoses (mono-infection or dual-infection) remained extremely low (<0.03% of all HIV infections). In addition, the overall number of false positive HIV-2 test results produced by the HIV-1/HIV-2 differentiation increased. The diagnostic value of a confirmatory antibody differentiation test in a setting with sensitive and specific screening tests and few HIV-2 infections might be limited. Evaluation and consideration of other HIV tests approved by the Food and Drug Administration (FDA) that might increase efficiencies in the CDC and Association of Public Health Laboratories-recommended HIV testing algorithm are warranted.


Assuntos
Testes Diagnósticos de Rotina/métodos , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , HIV-2/isolamento & purificação , Adolescente , Adulto , Algoritmos , Feminino , Infecções por HIV/epidemiologia , Humanos , Laboratórios , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto Jovem
3.
BMC Infect Dis ; 19(1): 1017, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791265

RESUMO

BACKGROUND: Early diagnosis and treatment of neurosyphilis is of great significance for regression. There is no gold standard for the diagnosis of neurosyphilis. We did this study to explore the factors associated with the clinical diagnosis of neurosyphilis and assess their accuracy for the diagnosis of neurosyphilis. METHODS: We retrospectively reviewed 100 cases of syphilis patients who underwent lumbar puncture at a major dermatology hospital in Guangzhou, China between April 2013 and November 2016. Fifty patients who were clinically diagnosed with neurosyphilis were selected as case group. Control group consisted of 50 general syphilis patients who were matched with age and gender. The records of patients were reviewed to collect data of socio-demographic information, clinical symptom, and laboratory indicators. Multivariable logistic regression was used to explore diagnostic indictors, and ROC analysis was used to assess diagnostic accuracy. RESULTS: Neurological symptoms (odds ratio (OR) = 59.281, 95% CI:5.215-662.910, P = 0.001), cerebrospinal fluid (CSF) Treponema pallidum particle agglutination (TPPA) titer (OR = 1.004, 95% CI:1.002-1.006, P < 0.001), CSF protein (OR = 1.005, 95% CI:1.000-1.009, P = 0.041), and CSF white blood cell (WBC) (OR = 1.120, 95% CI:1.017-1.233, P = 0.021) were found to be statistically associated with neurosyphilis. In ROC analysis, CSF TPPA titer had a sensitivity of 90%, a specificity of 84%, and an area under curve (AUC) of 0.941. CONCLUSION: CSF TPPA can potentially be considered as an alternative test for diagnosis of neurosyphilis. Combining with neurological symptoms, CSF protein, CSF WBC, the diagnosis would have a higher sensitivity.


Assuntos
Soronegatividade para HIV , Neurossífilis/diagnóstico , Adulto , Estudos de Casos e Controles , China/epidemiologia , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/normas , Feminino , Infecções por HIV/líquido cefalorraquidiano , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neurossífilis/líquido cefalorraquidiano , Neurossífilis/complicações , Neurossífilis/epidemiologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Sífilis/líquido cefalorraquidiano , Sífilis/complicações , Sífilis/diagnóstico , Sífilis/epidemiologia , Treponema pallidum
4.
BMC Infect Dis ; 19(1): 993, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752713

RESUMO

BACKGROUND: The goal of this study was to further investigate the clinical effectiveness of the T-SPOT.TB test in diagnosing tuberculosis (TB), including the effects of T-SPOT.TB test on evaluating diverse TB types and locations. METHODS: We collected 20,332 specimens from patients suspected to have TB. Afterwards, we performed an integrative analysis of T-SPOT.TB results and clinical diagnoses, and evaluated the composition ratio and positive detection rate of the T-SPOT.TB test in various age groups, sample types, and hospital departments. In addition, we compared the spot number and composition rate between latent TB infection (LTBI), active TB infection, and old TB infection groups. The active TB group was then further divided into pulmonary TB (PTB), pulmonary and extrapulmonary TB (PETB), and extrapulmonary TB (EPTB) subgroups, and we evaluated whether there were statistical differences in spot number and composition rate between subgroups. RESULTS: Positive results from the T-SPOT.TB test were found across different age groups, specimen types, and hospital departments. Elderly patient groups, pleural effusion samples, and thoracic surgery departments showed the highest rates of positivity. There were no statistically significant differences in spot number of CFP-10 and ESAT-6 wells between disease groups or active TB subgroups. The composition rate, however, was significantly different when ESAT-6 and CFP-10 wells were double-positive. The spot number and composition rate were statistically different between the three disease groups, but showed no significant differences between the three subgroups of active TB. CONCLUSIONS: The results of T-SPOT. TB test showed differences in LTBI, active TB and old TB. Additionally, a higher spot number level was observed in the active TB group.


Assuntos
Testes Diagnósticos de Rotina/métodos , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Resultado do Tratamento , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/microbiologia , Adulto Jovem
5.
Arch Virol ; 164(12): 3007-3017, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31598846

RESUMO

Classical swine fever (CSF) is an important viral disease of domestic pigs and wild boar. The structural proteins E2 and Erns of classical swine fever virus (CSFV), which participate in the attachment of the virion to the host cell surface and its subsequent entry, are immunogenic. The E2 and Erns proteins are used for diagnosis and the development of vaccines against CSFV infection in swine. Newcastle disease virus (NDV) has been successfully used as a viral vector to express heterologous proteins. In the present study, the E2 and Erns proteins of CSFV were expressed in cell culture as well as embryonated chicken eggs, using recombinant NDV (rNDV). Rescued rNDV expressing the E2 and Erns proteins induced the production of CSFV-neutralizing antibodies upon intranasal vaccination of pigs. Serum samples from vaccinated animals were found to neutralize both homologous and heterologous CSFV strains. Furthermore, rNDV expressing the E2 and Erns proteins of CSFV was used to develop an indirect ELISA, which was used to measure the the antibody titers of randomly collected serum samples. The results suggested that the ELISA based on rNDV-expressed E2 and Erns proteins could be used to screen for CSFV infections. This study shows that rNDV-based expression of CSFV antigens is potentially applicable for development of vaccines and diagnostic tests for CSFV infection. This approach could be an economically favorable alternative to the existing vaccine and diagnostics for CSFV in pigs.


Assuntos
Vírus da Febre Suína Clássica/imunologia , Peste Suína Clássica/diagnóstico , Testes Diagnósticos de Rotina/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas de Membrana/sangue , Vírus da Doença de Newcastle/genética , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Peste Suína Clássica/sangue , Peste Suína Clássica/imunologia , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/genética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Vírus da Doença de Newcastle/imunologia , Recombinação Genética , Suínos
6.
Malar J ; 18(1): 348, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619246

RESUMO

BACKGROUND: Widespread elimination of malaria requires an ultra-sensitive detection method that can detect low parasitaemia levels seen in asymptomatic carriers who act as reservoirs for further transmission of the disease, but is inexpensive and easy to deploy in the field in low income settings. It was hypothesized that a new method of malaria detection based on infrared spectroscopy, shown in the laboratory to have similar sensitivity to PCR based detection, could prove effective in detecting malaria in a field setting using cheap portable units with data management systems allowing them to be used by users inexpert in spectroscopy. This study was designed to determine whether the methodology developed in the laboratory could be translated to the field to diagnose the presence of Plasmodium in the blood of patients presenting at hospital with symptoms of malaria, as a precursor to trials testing the sensitivity of to detect asymptomatic carriers. METHODS: The field study tested 318 patients presenting with suspected malaria at four regional clinics in Thailand. Two portable infrared spectrometers were employed, operated from a laptop computer or a mobile telephone with in-built software that guided the user through the simple measurement steps. Diagnostic modelling and validation testing using linear and machine learning approaches was performed against the gold standard qPCR. Sample spectra from 318 patients were used for building calibration models (112 positive and 110 negative samples according to PCR testing) and independent validation testing (39 positive and 57 negatives samples by PCR). RESULTS: The machine learning classification (support vector machines; SVM) performed with 92% sensitivity (3 false negatives) and 97% specificity (2 false positives). The Area Under the Receiver Operation Curve (AUROC) for the SVM classification was 0.98. These results may be better than as stated as one of the spectroscopy false positives was infected by a Plasmodium species other than Plasmodium falciparum or Plasmodium vivax, not detected by the PCR primers employed. CONCLUSIONS: In conclusion, it was demonstrated that ATR-FTIR spectroscopy could be used as an efficient and reliable malaria diagnostic tool and has the potential to be developed for use at point of care under tropical field conditions with spectra able to be analysed via a Cloud-based system, and the diagnostic results returned to the user's mobile telephone or computer. The combination of accessibility to mass screening, high sensitivity and selectivity, low logistics requirements and portability, makes this new approach a potentially outstanding tool in the context of malaria elimination programmes. The next step in the experimental programme now underway is to reduce the sample requirements to fingerprick volumes.


Assuntos
Computação em Nuvem , Testes Diagnósticos de Rotina/métodos , Gerenciamento Clínico , Malária/diagnóstico , Espectrofotometria Infravermelho/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Tailândia , Adulto Jovem
7.
Intervirology ; 62(3-4): 145-155, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31533104

RESUMO

BACKGROUND: When infected with the chikungunya virus (CHIKV), 3% to 28% of CHIKV-infected individuals remain asymptomatic, necessitating the development of improved high-throughput screening methods to overcome the limitations of molecular diagnostics or enzyme-linked immunosorbent assays (ELISAs). OBJECTIVE: In this study, two novel monoclonal antibodies (mAbs) targeting envelope 1 (E1) of CHIKV were developed and applied in a fluorescence-linked immunosorbent assay (FLISA) using coumarin-derived dendrimer as the fluorophore. METHODS: The performance of the FLISA was compared with that of ELISA. RESULTS: Using the two novel mAbs (2B5 and 2C8), FLISA could detect 1 × 105 PFU/mL of CHIKV, exhibiting a 2-fold lower limit of detection (LOD) compared to ELISA. The LOD of FICT corresponded to a comparative threshold value of 23.95 and 4 × 106 of RNA copy number/µL. In the presence of human sera and blood, virus detection by FLISA was 3-fold better than ELISA, with an LOD of 2 × 105 PFU/mL. Sera and blood interfered with the ELISA, resulting in 6 × 105 PFU/mL as the LOD. CONCLUSIONS: FLISA using two novel mAbs and coumarin-derived dendrimer is a superior diagnostic assay for detecting CHIKV in human sera and blood, compared to conventional ELISA.


Assuntos
Antígenos Virais/análise , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , Fluorometria/métodos , Técnicas Imunoenzimáticas/métodos , Proteínas do Envelope Viral/análise , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , Vírus Chikungunya/imunologia , Humanos , Sensibilidade e Especificidade
8.
Malar J ; 18(1): 313, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533756

RESUMO

BACKGROUND: Malaria continues to impose a tremendous burden in terms of global morbidity and mortality, yet even today, a large number of diagnoses are presumptive resulting in lack of or inappropriate treatment. METHODS: In this work, a two-colour lateral flow immunoassay (LFA) system was developed to identify infections by Plasmodium spp. and differentiate Plasmodium falciparum infection from the other three human malaria species (Plasmodium vivax, Plasmodium ovale, Plasmodium malariae). To achieve this goal, red and blue colours were encoded to two markers on a single test line of strips, for simultaneous detection of PfHRP2 (red), a marker specific for P. falciparum infection, and pLDH (blue), a pan-specific marker for infections by all species of Plasmodium. The assay performance was first optimized and evaluated with recombinant malarial proteins spiked in washing buffer at various concentrations from 0 to 1000 ng mL-1. The colour profiles developed on the single test line were discriminated and quantified: colour types corresponded to malaria protein species; colour intensities represented protein concentration levels. RESULTS: The limit of detection (the lowest concentrations of malaria antigens that can be distinguished from blank samples) and the limit of colour discrimination (the limit to differentiate pLDH from PfHRP2) were defined for the two-colour assay from the spiked buffer test, and the two limits were 31.2 ng mL-1 and 7.8 ng mL-1, respectively. To further validate the efficacy of the assay, 25 human whole blood frozen samples were tested and successfully validated against ELISA and microscopy results: 15 samples showed malaria negative; 5 samples showed P. falciparum positive; 5 samples showed P. falciparum negative, but contained other malaria species. CONCLUSIONS: The assay provides a simple method to quickly identify and differentiate infection by different malarial parasites at the point-of-need and overcome the physical limitations of traditional LFAs, improving the multiplexing potential for simultaneous detection of various biomarkers.


Assuntos
Testes Diagnósticos de Rotina/métodos , Imunoensaio/métodos , Malária/diagnóstico , Plasmodium/isolamento & purificação , Humanos , Malária/classificação
9.
Parasit Vectors ; 12(1): 424, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31522683

RESUMO

BACKGROUND: Trypanosoma cruzi, the protozoan agent of Chagas disease, is comprised of at least 6 genetic lineages (TcI-TcVI). Their geographical distribution, clinical associations and reservoir hosts are not fully elucidated, as genotyping is hampered due to the difficulty in isolating representative populations of organisms. Lineage-specific serological techniques may address these issues. METHODS: Trypanosoma cruzi lineage-specific serological assays were performed on human, canine, feline and armadillo sera from the Gran Chaco in northern Argentina, a region of ongoing transmission. Synthetic peptides representing lineage-specific epitopes of the trypomastigote small surface antigen (TSSA) were used in ELISA, and the TcII/V/VI shared epitope peptide (TSSApep-II/V/VI) was used in the Chagas Sero K-SeT rapid diagnostic test (RDT). RESULTS: Chagas Sero K-SeT RDT, using Protein G to detect human and canine IgG, was at least as sensitive as TSSApep-II/V/VI ELISA using specific secondary antibodies. For sera from humans TSSApep-II/V/VI seroprevalence by Chagas Sero K-SeT was 273/393 (69.5%), for dogs 48/73 (65.8%) and for armadillos 1/7 (14.3%); by ELISA for cats 5/19 (26.3%). The seroprevalence for humans was similar to that for Bolivian patients, amongst whom we previously observed an association of TSSApep-II/V/VI seropositivity with severity of cardiomyopathy. In humans, prevalence of TSSApep-II/V/VI recognition was associated with locality, and with increasing and decreasing age within the Qom and Creole populations, respectively. For dogs TSSApep-II/V/VI recognition was associated with being born before community-wide insecticide spraying (P = 0.05) and with Qom household (P < 0.001). CONCLUSIONS: We show here that Chagas Sero K-SeT RDT can replace ELISA for TSSApep-II/V/VI serology of humans and dogs; for humans there were statistically significant associations between a positive Chagas Sero K-SeT RDT and being resident in Area IV, and for dogs association with Qom household or with being born before the mass spraying campaign; we also show that with cats the TcII/V/VI epitope can be detected by ELISA. We assessed the lineage distribution in an unprecedented 83% of the human T. cruzi-seropositive population. These results form the basis for more detailed studies, enabling rapid in-the-field surveillance of the distribution and clustering of these lineages among humans and mammalian reservoirs of T. cruzi infection.


Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Testes Diagnósticos de Rotina/métodos , Sorogrupo , Testes Sorológicos/métodos , Trypanosoma cruzi/classificação , Animais , Argentina/epidemiologia , Tatus , Gatos , Doença de Chagas/parasitologia , Estudos Transversais , Cães , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Estudos Soroepidemiológicos , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação
10.
Parasit Vectors ; 12(1): 439, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31522684

RESUMO

BACKGROUND: Schistosomiasis and food-borne trematodiases are not only of major public health concern, but can also have profound implications for livestock production and wildlife conservation. The zoonotic, multi-host nature of many digenean trematodes is a significant challenge for disease control programmes in endemic areas. However, our understanding of the epidemiological role that animal reservoirs, particularly wild hosts, may play in the transmission of zoonotic trematodiases suffers a dearth of information, with few, if any, standardised, reliable diagnostic tests available. We combined qualitative and quantitative data derived from post-mortem examinations, coprological analyses using the Mini-FLOTAC technique, and molecular tools to assess parasite community composition and the validity of non-invasive methods to detect trematode infections in 89 wild Hubert's multimammate mice (Mastomys huberti) from northern Senegal. RESULTS: Parasites isolated at post-mortem examination were identified as Plagiorchis sp., Anchitrema sp., Echinostoma caproni, Schistosoma mansoni, and a hybrid between Schistosoma haematobium and Schistosoma bovis. The reports of E. caproni and Anchitrema sp. represent the first molecularly confirmed identifications for these trematodes in definitive hosts of sub-Saharan Africa. Comparison of prevalence estimates derived from parasitological analysis at post-mortem examination and Mini-FLOTAC analysis showed non-significant differences indicating comparable results between the two techniques (P = 1.00 for S. mansoni; P = 0.85 for E. caproni; P = 0.83 for Plagiorchis sp.). A Bayesian model, applied to estimate the sensitivities of the two tests for the diagnosis of Schistosoma infections, indicated similar median posterior probabilities of 83.1% for Mini-FLOTAC technique and 82.9% for post-mortem examination (95% Bayesian credible intervals of 64.0-94.6% and 63.7-94.7%, respectively). CONCLUSIONS: Our results showed that the Mini-FLOTAC could be applied as an alternative diagnostic technique for the detection of the zoonotic S. mansoni and other trematodes in rodent reservoirs. The implementation of non-invasive diagnostics in wildlife would offer numerous advantages over lethal sampling methodologies, with potential impact on control strategies of zoonotic helminthiases in endemic areas of sub-Saharan Africa and on fostering a framework of animal use reduction in scientific practice.


Assuntos
Testes Diagnósticos de Rotina/métodos , Murinae , Parasitologia/métodos , Doenças dos Roedores/diagnóstico , Trematódeos/classificação , Trematódeos/isolamento & purificação , Infecções por Trematódeos/veterinária , Animais , Prevalência , Doenças dos Roedores/parasitologia , Senegal , Sensibilidade e Especificidade , Infecções por Trematódeos/diagnóstico
11.
Parasit Vectors ; 12(1): 443, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31522691

RESUMO

BACKGROUND: The strategy of pooling stool specimens has been extensively used in the field of parasitology in order to facilitate the screening of large numbers of samples whilst minimizing the prohibitive cost of single sample analysis. The aim of this study was to develop a standardized reproducible pooling protocol for stool samples, validated between two different laboratories, without jeopardizing the sensitivity of the quantitative polymerase chain reaction (qPCR) assays employed for the detection of soil-transmitted helminths (STHs). Two distinct experimental phases were recruited. First, the sensitivity and specificity of the established protocol was assessed by real-time PCR for each one of the STHs. Secondly, agreement and reproducibility of the protocol between the two different laboratories were tested. The need for multiple stool sampling to avoid false negative results was also assessed. Finally, a cost exercise was conducted which included labour cost in low- and high-wage settings, consumable cost, prevalence of a single STH species, and a simple distribution pattern of the positive samples in pools to estimate time and money savings suggested by the strategy. RESULTS: The sensitivity of the pooling method was variable among the STH species but consistent between the two laboratories. Estimates of specificity indicate a 'pooling approach' can yield a low frequency of 'missed' infections. There were no significant differences regarding the execution of the protocol and the subsequent STH detection between the two laboratories, which suggests in most cases the protocol is reproducible by adequately trained staff. Finally, given the high degree of agreement, there appears to be little or no need for multiple sampling of either individuals or pools. CONCLUSIONS: Our results suggest that the pooling protocol developed herein is a robust and efficient strategy for the detection of STHs in 'pools-of-five'. There is notable complexity of the pool preparation to ensure even distribution of helminth DNA throughout. Therefore, at a given setting, cost of labour among other logistical and epidemiological factors, is the more concerning and determining factor when choosing pooling strategies, rather than losing sensitivity and/or specificity of the molecular assay or the method.


Assuntos
Testes Diagnósticos de Rotina/métodos , Fezes/parasitologia , Helmintíase/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Manejo de Espécimes/métodos , Custos e Análise de Custo , Testes Diagnósticos de Rotina/economia , Humanos , Técnicas de Diagnóstico Molecular/economia , Reação em Cadeia da Polimerase/economia , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes/economia
13.
Intervirology ; 62(3-4): 164-168, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31487720

RESUMO

Despite the significant medical advances which have taken place in the last decades, acute diarrhoea cases remain a public health issue of major significance, with gastroenteritis agents being associated with severe symptoms in adults and high morbidity in infants and children. Regarding rotaviruses, while children are the predominant victims of rotavirus infection, adults (often caretakers or parents of these children) may experience the same symptoms of fever, vomiting, and non-bloody diarrhoea. Three different routine schemes for the detection of rotaviruses in archived stool samples were evaluated in terms of diagnostic performance. A total of 640 archived stool samples were included in the study. The samples were screened with three different techniques: a commercial rapid immunochromatographic test, a modified in-house conventional one-step reverse-transcription polymerase chain reaction (PCR) screen protocol, and a com-mer-cial one-step real-time PCR kit. Technical aspects and considerations are discussed.


Assuntos
Testes Diagnósticos de Rotina/métodos , Imunoensaio/métodos , Infecções por Rotavirus/diagnóstico , Rotavirus/isolamento & purificação , Diarreia/diagnóstico , Diarreia/virologia , Fezes/virologia , Gastroenterite/diagnóstico , Gastroenterite/virologia , Grécia , Humanos , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Rotavirus/imunologia , Sensibilidade e Especificidade , Centros de Atenção Terciária
14.
Helicobacter ; 24 Suppl 1: e12641, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31486244

RESUMO

Endoscopic imaging of the stomach is improving. In addition to narrow band imaging, other methods, for example, blue light imaging and linked color imaging, are now available and can be combined with artificial intelligence systems to obtain information on the gastric mucosa and detect early gastric cancer. Immunohistochemistry is only recommended as an ancillary stain in case of chronic active gastritis without Helicobacter pylori detection by standard staining, and recommendations to exclude false negative H. pylori results have been made. Molecular methods using real-time PCR, droplet digital PCR, or amplification refractory mutation system PCR have shown a high accuracy, both for detecting H. pylori and for clarithromycin susceptibility testing, and can now be used in clinical practice for targeted therapy. The most reliable non-invasive test remains the 13 C-urea breath test. Large data sets show that DOB values are higher in women and that the cut-off for positivity could be decreased to 2.74 DOB. Stool antigen tests using monoclonal antibodies are widely used and may be a good alternative to UBT, particularly in countries with a high prevalence of H. pylori infection. Attempts to improve serology by looking at specific immunodominant antigens to distinguish current and past infection have been made. The interest of Gastropanel® which also tests pepsinogen levels was confirmed.


Assuntos
Testes Respiratórios/métodos , Testes Diagnósticos de Rotina/métodos , Endoscopia Gastrointestinal/métodos , Infecções por Helicobacter/diagnóstico , Imunoensaio/métodos , Técnicas de Diagnóstico Molecular/métodos , Testes Diagnósticos de Rotina/tendências , Endoscopia Gastrointestinal/tendências , Humanos , Imunoensaio/tendências , Técnicas de Diagnóstico Molecular/tendências
15.
West Afr J Med ; 36(2): 112-115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31385595

RESUMO

BACKGROUND: Laboratory request forms serve as a medium for communication between clinicians managing medical cases and the pathologist. Improperly filled forms impairs the ability of pathologists to generate sound and valuable reports. This research focused on finding out the extent to which doctors in Federal Medical Centre, Umuahia properly fill laboratory request forms. METHODOLOGY: A total of 1,509 laboratory request forms directed to the electrolyte bench, already filled out by various doctors in the hospital between May and October, 2018 were retrospectively studied. The completeness of information supplied by requesting physician based on some parameters were analysed. RESULTS: In descending order, the most frequently provided data were as follows; name of patient, 1,509[100.0%]; gender,973[64.5%]; provisional diagnosis,866[57.4%]; age,639[42.4%]; hospital number,428[28.4%]; clinical summary,47[3.1%]. 26[2%] forms were completed in their entirety per the 6 variables assessed. CONCLUSION: Proper and adequate filling of laboratory request forms is very poor in this hospital. Therefore, continuous medical education on the need for adequate completion of request forms is absolutely necessary.


Assuntos
Serviços de Diagnóstico/estatística & dados numéricos , Controle de Formulários e Registros , Laboratórios Hospitalares , Médicos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Sistemas de Informação em Laboratório Clínico , Serviços de Laboratório Clínico , Testes Diagnósticos de Rotina/métodos , Hospitais , Humanos , Nigéria , Estudos Retrospectivos
16.
Acta Trop ; 200: 105125, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31394079

RESUMO

Highly-sensitive and field-friendly diagnostic tools are needed for accurate detection of low-density malaria infections. Although loop-mediated isothermal amplification (LAMP) fulfills these conditions, operational challenges are still encountered during pilot population screenings in remote settings when employing Loopamp™ MALARIA Pan/Pf detection kit (Eiken Chemical Co.). This study evaluates different procedures for the simplification of sample preparation and result reading steps of current LAMP protocols. The reference 'Boil & Spin' (B&S) pre-amplification procedure was compared to three alternative methods, along with a colorimetric staining protocol based on malachite green. Results suggested that the B&S supernatant transference step may be omitted without an impact on test performance, even when colorimetry was incorporated to facilitate results visualization. Procedures skipping centrifugation and/or heat-incubation were proved to be compatible with LAMP-based malaria DNA detection, but resulted in a low-to-moderate decrease in sensitivity and ambiguous result interpretation for the most straightforward protocol. Nevertheless, all simplified LAMP methods could still reach lower limits of detection than the currently used tools for malaria mass-screening (i.e. microscopy and rapid tests), indicating that these alternative strategies may deserve further consideration. This evaluation, therefore, demonstrates the feasibility of skipping some of the main procedural bottlenecks of LAMP-malaria protocols, a much-needed achievement to make point-of-care implementation of molecular diagnostics a reality.


Assuntos
Testes Diagnósticos de Rotina/métodos , Malária/diagnóstico , Programas de Rastreamento/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Plasmodium/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Projetos Piloto , Sensibilidade e Especificidade
17.
BMC Biol ; 17(1): 65, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31405370

RESUMO

BACKGROUND: Effective disease management depends on timely and accurate diagnosis to guide control measures. The capacity to distinguish between individuals in a pathogen population with specific properties such as fungicide resistance, toxin production and virulence profiles is often essential to inform disease management approaches. The genomics revolution has led to technologies that can rapidly produce high-resolution genotypic information to define individual variants of a pathogen species. However, their application to complex fungal pathogens has remained limited due to the frequent inability to culture these pathogens in the absence of their host and their large genome sizes. RESULTS: Here, we describe the development of Mobile And Real-time PLant disEase (MARPLE) diagnostics, a portable, genomics-based, point-of-care approach specifically tailored to identify individual strains of complex fungal plant pathogens. We used targeted sequencing to overcome limitations associated with the size of fungal genomes and their often obligately biotrophic nature. Focusing on the wheat yellow rust pathogen, Puccinia striiformis f.sp. tritici (Pst), we demonstrate that our approach can be used to rapidly define individual strains, assign strains to distinct genetic lineages that have been shown to correlate tightly with their virulence profiles and monitor genes of importance. CONCLUSIONS: MARPLE diagnostics enables rapid identification of individual pathogen strains and has the potential to monitor those with specific properties such as fungicide resistance directly from field-collected infected plant tissue in situ. Generating results within 48 h of field sampling, this new strategy has far-reaching implications for tracking plant health threats.


Assuntos
Basidiomycota/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , Doenças das Plantas/microbiologia , Sistemas Automatizados de Assistência Junto ao Leito , Basidiomycota/classificação , Doenças das Plantas/classificação
18.
Parasitol Res ; 118(10): 2891-2899, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418112

RESUMO

Immunodiagnosis has a supportive role in the diagnosis of neurocysticercosis (NCC). The aim of this study was to compare the validity of seven immunodiagnostic tests among serum samples from 58 patients with NCC, 26 patients with neurological diseases other than NCC, and 15 healthy controls. One test for viable parasite detection (HP10 antigen assay) and six for antibody detection were evaluated. For the entire sample, sensitivities ranged from 55.2% (NOVALISA) to 81.0% (enzyme-linked immunosorbent assay [ELISA] Taenia solium antibody), with the sensitivity of the latter test significantly higher than that of the in-house ELISA Taenia crassiceps, NOVALISA, enzyme-linked immunoelectrotransfer blot (EITB) CDC, and HP10. Overall, specificities were high, ranging from 85.4% (ELISA Ts) to 97.1% (NOVALISA), with no statistically significant differences. Detection of HP10 antigen was significantly associated with the presence of vesicular parasites. The simple and low-cost ELISA Taenia solium antibody Ab instead of EITB is recommended to support NCC diagnosis in both rural and hospital settings in Mexico.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Testes Diagnósticos de Rotina/métodos , Neurocisticercose/diagnóstico , Taenia solium/imunologia , Adulto , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Testes Imunológicos/métodos , Masculino , México , Neurocisticercose/imunologia , População Rural , Sensibilidade e Especificidade
19.
Malar J ; 18(1): 288, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455349

RESUMO

BACKGROUND: The Gambia has successfully reduced malaria transmission. The human reservoir of infection could further decrease if malaria-infected individuals could be identified by highly sensitive, field-based, diagnostic tools and then treated. METHODS: A cross-sectional survey was done at the peak of the 2017 malaria season in 47 Gambian villages. From each village, 100 residents were randomly selected for finger-prick blood samples to detect Plasmodium falciparum infections using highly sensitive rapid diagnostic tests (HS-RDT) and PCR. The sensitivity and specificity of the HS-RDT were estimated (assuming PCR as the gold standard) across varying transmission intensities and in different age groups. A deterministic, age-structured, dynamic model of malaria transmission was used to estimate the impact of mass testing and treatment (MTAT) with HS-RDT in four different scenarios of malaria prevalence by PCR: 5, 15, 30, and 60%, and with seasonal transmission. The impact was compared both to MTAT with conventional RDT and mass drug administration (MDA). RESULTS: Malaria prevalence by HS-RDT was 15% (570/3798; 95% CI 13.9-16.1). The HS-RDT sensitivity and specificity were 38.4% (191/497, 95% CI 34.2-42.71) and 88.5% (2922/3301; 95% CI 87.4-89.6), respectively. Sensitivity was the highest (50.9%, 95% CI 43.3-58.5%) in high prevalence villages (20-50% by PCR). The model predicted that in very low transmission areas (≤ 5%), three monthly rounds of MTAT with HS-RDT, starting towards the end of the dry season and testing 65 or 85% of the population for 2 consecutive years, would avert 62 or 78% of malaria cases (over 2 years), respectively. The effect of the intervention would be lower in a moderate transmission setting. In all settings, MDA would be superior to MTAT with HS-RDT which would be superior to MTAT with conventional RDT. CONCLUSION: The HS-RDT's field sensitivity was modest and varied by transmission intensity. In low to very low transmission areas, three monthly rounds per year of MTAT with HS-RDT at 85% coverage for 2 consecutive years would reduce malaria prevalence to such low levels that additional strategies may achieve elimination. The model prediction would need to be confirmed by cluster-randomized trials.


Assuntos
Testes Diagnósticos de Rotina/métodos , Malária Falciparum/diagnóstico , Plasmodium falciparum/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Gâmbia/epidemiologia , Humanos , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade , Adulto Jovem
20.
Surg Infect (Larchmt) ; 20(7): 535-540, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31429644

RESUMO

Background: As the use of patient-owned devices, including smartphones and tablets, to manage day-to-day activities grows, so does healthcare industry's interest to better leverage technology to engage patients. For surgical care, a unique opportunity exists to capture patient-generated health data (PGHD) including photographs. As part of a broader initiative to evaluate PGHD for surgical site infection (SSI) surveillance, we sought evidence regarding patient involvement and experience with PGHD for SSI monitoring and surveillance. Methods: Through a scoping review of the literature and semi-structured stakeholder interviews we gathered evidence on what is currently known about patient perspectives of and experiences with mobile health (mHealth) interventions for post-operative recovery. We presented findings to and discussed with the ASSIST PGHD Stakeholder Advisory Group (PSAG) to generate priorities for further examination. Results: Our scoping review yielded 34 studies that addressed post-discharge use of PGHD for monitoring and surveillance of SSI. Of these, 16 studies addressed at least one outcome regarding patient experience; the most commonly measured outcome was patient satisfaction. Only three studies reported on patient involvement in the development of PGHD tools and interventions. We conducted interviews (n = 24) representing a range of stakeholder perspectives. Interviewees stressed the importance of patient involvement in tool and program design, noting patient involvement ensures the "work" that patients do in their daily lives to manage their health and healthcare is recognized. Discussion of evidence with the ASSIST PSAG resulted in formal recommendations for direct involvement of patients and caregivers for future work. Conclusions: While mHealth initiatives to advance post-operative management offer the ability to improve patient engagement, work is needed to ensure the patient voice is reflected. Active engagement with patients and caregivers in the development of new technology, the design of new workflows, and the conduct of research and evaluation ensures that the patient experiences and values are incorporated.


Assuntos
Testes Diagnósticos de Rotina/métodos , Monitoramento Epidemiológico , Participação do Paciente/métodos , Infecção da Ferida Cirúrgica/diagnóstico por imagem , Telemedicina/métodos , Processamento Eletrônico de Dados/métodos , Humanos , Dados de Saúde Gerados pelo Paciente
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