Detection of Multidrug‑Resistant Tuberculosis from Stored DNA Samples: A Multicenter Study

MARIE SYLVIANNE RABODOARIVELO; BRANDAO A; CERGOLE NOVELLA MC; A. G. C. BOMBONATTE; B R IMPERIALE; N. RAKOTOSAMIMANANA; MORCILLO N; V. RASOLOFO; J C PALOMINO; MARTIN A

International Journal of Mycobacteriology

Wolters Kluwer - Medknow Publications Wolters Kluwer India Pvt. Ltd.

Año: 2018 vol. 7 p. 40 - 44

2212-5531

Background: In low‑income countries, rapid detection of tuberculosis(TB) drug resistance is often restricted by the difficulties of transportingand storing sputum samples from remote health centers to the reference laboratories where molecular tests are available. The aim of thisstudy was to evaluate the performance of four transport and storage systems for molecular detection of rifampicin (RIF) and isoniazid (INH)resistance. Methods: This was a multicenter study. Molecular detection of RIF and INH resistance was performed directly from smear‑positiveTB sputa spotted on a slide, FTA card, GenoCard, and ethanol using the Genotype MTBDRplus assay. The performance of the DNA extractionmethod from each storage support to detect drug resistance was assessed by calculating their sensitivity and specificity compared to thephenotypic method. Results: From all sites, the overall sensitivity and specificity for RIF‑resistance detection was 88% and 85%, respectively,for slides, 86% and 92%, respectively, for GenoCard, 87% and 89%, respectively, for FTA card, and 88% and 92%, respectively, for ethanol.For INH‑resistance detection, the overall sensitivity and specificity was 82% and 90%, respectively, for slides, 85% and 96%, respectively,for GenoCard, 86% and 92%, respectively, for FTA card, and 86% and 94%, respectively, for ethanol. Conclusion: Smear slides and filtercards showed to be very useful tools to facilitate DNA extraction from sputum samples with the potential to accelerate the detection of drugresistance in remote areas.