Use of mycobacteriophage quantitative PCR on MGIT broths for a rapid tuberculosis antibiogram.
J Clin Microbiol
; 52(5): 1523-8, 2014 May.
Article
en En
| MEDLINE
| ID: mdl-24574299
ABSTRACT
Phenotypic culture-based drug susceptibility testing (DST) for Mycobacterium tuberculosis is a valuable tool to identify four to six active drugs for individualized multidrug-resistant (MDR) tuberculosis (TB) regimens. Current culture-based methods are slow, however; therefore, we evaluated a rapid mycobacteriophage-based quantitative PCR (qPCR) assay for use directly on M. tuberculosis-positive MGIT broths. We compared phage qPCRs, using a simple cutoff of 3 for the ΔCq value (where Cq is quantification cycle, and ΔCq is calculated as the Cq of starting phage minus the Cq of TB isolates in drug-containing medium), on 325 clinical M. tuberculosis MGIT broth cultures versus the respective subcultured isolates tested by agar proportion. The median accuracy for the 13 drugs/concentrations tested was 98%, with most discrepancies being false-resistant results. Evaluation of phage qPCR on greater numbers of resistant strains of 393 isolates grown on Löwenstein-Jensen medium showed similar findings, with a median accuracy, sensitivity, and specificity of 97%, 90%, and 99%, respectively. This rapid culture-based DST methodology can be performed for any drug on TB-positive MGIT broths, with a specimen-to-antibiogram turnaround time of approximately 23.9 days, compared with waiting 58.6 days for isolate growth on solid medium followed by agar proportion DST.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Pruebas de Sensibilidad Microbiana
/
Micobacteriófagos
/
Mycobacterium tuberculosis
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
J Clin Microbiol
Año:
2014
Tipo del documento:
Article
País de afiliación:
Tailandia