Journal of clinical microbiology
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J. Clin. Microbiol. · Apr 2015
Evaluation of Ebola virus inactivation procedures for Plasmodium falciparum malaria diagnostics.
Plasmodium falciparum malaria is highly endemic in the three most affected countries in the current epidemic of Ebola virus disease (EVD) in West Africa. As EVD and malaria are clinically indistinguishable, both remain part of the differential diagnosis of ill travelers from returning from areas of EVD transmission. We compared the performances of a rapid diagnostic test (BinaxNOW) and real-time PCR with P. falciparum-positive specimens before and after heat and Triton X-100 inactivation, and we documented no loss of sensitivity.
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J. Clin. Microbiol. · Apr 2015
Utility of sequencing the erm(41) gene in isolates of Mycobacterium abscessus subsp. abscessus with low and intermediate clarithromycin MICs.
The erm(41) gene confers inducible macrolide resistance in Mycobacterium abscessus subsp. abscessus, calling into question the usefulness of macrolides for treating M. abscessus subsp. abscessus infections. With an extended incubation (14 days), isolates with MICs of ≥8 μg/ml are considered macrolide resistant by current CLSI guidelines. Our goals were to determine the incidence of macrolide susceptibility in U. ⋯ Our studies suggest that macrolides are useful for treating approximately 20% of U. S. isolates of M. abscessus subsp. abscessus. Sequencing of the erm gene of M. abscessus subsp. abscessus will predict inducible macrolide susceptibility.
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J. Clin. Microbiol. · Apr 2015
Diagnostic accuracy of presepsin (sCD14-ST) for prediction of bacterial infection in cerebrospinal fluid samples from children with suspected bacterial meningitis or ventriculitis.
Children with temporary external ventricular drains (EVD) are prone to nosocomial infections. Diagnosis of bacterial meningitis and ventriculitis in these children is challenging due to frequent blood contamination of cerebrospinal fluid (CSF) and the presence of chemical ventriculitis. The aim of this study was to compare diagnostic accuracy of presepsin (sCD14-ST), a novel biomarker of bacterial infection in CSF, to predict bacterial infection in comparison to the accuracy of established biomarkers like those demonstrated in biochemical analysis of CSF. ⋯ It was found that presepsin was present at a significantly higher level in children with clinically proven ventriculitis than in those without meningitis or ventriculitis. Diagnostic accuracies of presepsin were superior to those of leukocytes or proteins in CSF. Presepsin-guided 16S rRNA gene PCR could be used in everyday clinical practice to improve etiological diagnosis of meningitis and ventriculitis and to prescribe more appropriate antibiotics.
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J. Clin. Microbiol. · Mar 2015
Validation of a new Aspergillus real-time PCR assay for direct detection of Aspergillus and azole resistance of Aspergillus fumigatus on bronchoalveolar lavage fluid.
Azole resistance in Aspergillus fumigatus is increasingly reported. Here, we describe the validation of the AsperGenius, a new multiplex real-time PCR assay consisting of two multiplex real-time PCRs, one that identifies the clinically relevant Aspergillus species, and one that detects the TR34, L98H, T289A, and Y121F mutations in CYP51A and differentiates susceptible from resistant A. fumigatus strains. The diagnostic performance of the AsperGenius assay was tested on 37 bronchoalveolar lavage (BAL) fluid samples from hematology patients and 40 BAL fluid samples from intensive care unit (ICU) patients using a BAL fluid galactomannan level of ≥1.0 or positive culture as the gold standard for detecting the presence of Aspergillus. ⋯ Voriconazole therapy failed for both patients. The AsperGenius multiplex real-time PCR assay allows for sensitive and fast detection of Aspergillus species directly from BAL fluid samples. More importantly, this assay detects and differentiates wild-type from resistant strains, even if BAL fluid cultures remain negative.