RESUMO
The performance characteristics of Xpect RSV (XP) and Binax Now RSV (BN) were compared to those of direct fluorescent-antibody staining and/or tissue culture for detection of respiratory syncytial virus (RSV) in nasopharyngeal aspirate and wash samples from children (n = 110) and adults (n = 66). The sensitivity, specificity, positive predictive value, and negative predictive value of XP were 75%, 98%, 95%, and 90%, respectively; and those of BN were 74%, 100%, 100%, and 90%, respectively. The performances of the assays were similar within a given age group and specimen type (nasopharyngeal aspirate or wash specimen). XP and BN are useful for screening for RSV in respiratory specimens when large volumes are tested or low levels of staffing occur.
Assuntos
Vírus Sincicial Respiratório Humano/isolamento & purificação , Virologia/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Técnica Direta de Fluorescência para Anticorpo/métodos , Técnica Direta de Fluorescência para Anticorpo/estatística & dados numéricos , Humanos , Lactente , Nasofaringe/virologia , Valor Preditivo dos Testes , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/virologia , Sensibilidade e Especificidade , Virologia/estatística & dados numéricosRESUMO
We evaluated a two-step algorithm for detecting toxigenic Clostridium difficile: an enzyme immunoassay for glutamate dehydrogenase antigen (Ag-EIA) and then, for antigen-positive specimens, a concurrent cell culture cytotoxicity neutralization assay (CCNA). Antigen-negative results were > or = 99% predictive of CCNA negativity. Because the Ag-EIA reduced cell culture workload by approximately 75 to 80% and two-step testing was complete in < or = 3 days, we decided that this algorithm would be effective. Over 6 months, our laboratories' expenses were US dollar 143,000 less than if CCNA alone had been performed on all 5,887 specimens.
Assuntos
Técnicas Bacteriológicas/métodos , Clostridioides difficile/isolamento & purificação , Algoritmos , Antígenos de Bactérias/análise , Técnicas Bacteriológicas/economia , Técnicas Bacteriológicas/estatística & dados numéricos , Clostridioides difficile/enzimologia , Clostridioides difficile/imunologia , Clostridioides difficile/patogenicidade , Custos e Análise de Custo , Citotoxinas/análise , Enterocolite Pseudomembranosa/diagnóstico , Glutamato Desidrogenase/imunologia , Humanos , Técnicas Imunoenzimáticas/economia , Técnicas Imunoenzimáticas/métodos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Testes de Neutralização , Sensibilidade e Especificidade , Design de SoftwareRESUMO
We reviewed the results of repeated sample submissions within a 7-day time frame for Clostridium difficile toxin testing. A total of 2,940 samples were tested during a 3-month period using a cell culture cytotoxicity assay (CCCA). The results from all second samples (n = 1,101) were concordant with the original test result. In only two cases (0.8%; n = 247) was a third sample positive when the first two samples were negative. In this study, submission of multiple samples for CCCA did not increase detection of Clostridium difficile infection.