An Innovative Multiplexed and Flexible Molecular Approach for the Differential Detection of Arboviruses.

Nucleic acid testing during the preseroconversion viremic phase is required to differentially diagnose arboviral infections. The continuing emergence of arboviruses, such as Zika virus (ZIKV), dengue virus (DENV), and chikungunya virus (CHIKV), necessitates the development of a flexible diagnostic approach. Similar clinical signs and the priority to protect pregnant women from ZIKV infection indicate that the differential diagnosis of arboviruses is essential for effective patient management, clinical care, and epidemiologic surveillance. We describe an innovative diagnostic approach that combines generic RT-PCR amplification and identification by hybridization to specific probes. Original tetrathiolated probes were designed for the robust, sensitive, and specific detection of amplified arboviral genomes. The limit of detection using cultured and quantified stocks of whole viruses was 1 TCID50/mL for DENV-1, DENV-3, and CHIKV and 10 TCID50/mL for DENV-2, DENV-4, and ZIKV. The assay had 100% specificity with no false-positive results. The approach was evaluated using 179 human samples that previously tested as positive for the presence of ZIKV, DENV, or CHIKV genomes. Accordingly, the diagnostic sensitivity for ZIKV, DENV, and CHIKV was 87.88% (n = 58/66), 96.67% (n = 58/60), and 94.34% (n = 50/53), respectively. This method could be easily adapted to include additional molecular targets. Moreover, this approach may also be adapted to develop highly specific, sensitive, and easy to handle platforms dedicated to the multiplex screening and identification of emerging viruses.

Performances of the heart fatty acid protein assay for the rapid diagnosis of acute myocardial infarction in ED patients.

OBJECTIVE: We sought to evaluate the added value of heart fatty acid protein assay (HFABP) for rapid diagnosis of acute myocardial infarction in a prospective cohort of emergency department (ED) patients with acute chest pain. METHODS: High-sensitivity cardiac troponin T (hs-cTnT; Roche Diagnostics, Meylan, France) and HFABP (Randox, Mauguio, France) were blindly assayed from venous blood samples obtained at admission. Diagnosis was made by 2 ED physicians using all available data and serial cardiac troponin I as the biochemical standard. Diagnostic performances of HFABP combined with hs-cTnT were assessed using logistic regression. Analysis was conducted in all patients and in patients without ST-elevation myocardial infarction. RESULTS: A total of 181 patients were included (age, 61 ±17 years; male sex, 66%). Acute myocardial infarction occurred in 47 (25.9%) patients, including non-ST-elevation myocardial infarction in 31 (17.1%). The receiver operating characteristic area under the curve was 0.893 for hs-cTnT levels at presentation (95% confidence interval, 0.812-0.974) and 0.908 (95% confidence interval, 0.839-0.977) for the combination of hs-cTnT and HFABP, with no significant (P=.07). Adding HFABP to hs-cTnT increased both sensitivity and negative predictive value (NPV) for non-ST-elevation myocardial infarction diagnosis, with about 13% and 3% increase, respectively, leading to a sensitivity of 97% and an NPV of 99%. CONCLUSION: The assessment of HFABP at ED admission adds incremental value to initial hs-cTnT. The increase of sensitivity and NPV without sacrificing the specificity and positive predictive value in patients with chest pain with noncontributive electrocardiogram could potentially allow safe and early rule out of acute myocardial infarction without the need for further serial troponin testing.