title: DNA extracted from stained sputum smears can be used in the MTBDRplus assay.
abstract: We examined the feasibility of using DNA extracted from stained sputum smears for the detection of rifampin and isoniazid resistance with the commercial MTBDRplus assay from Hain Lifescience GmbH, Nehren, Germany. Overall sensitivity was initially low (70.0%) but increased to 96.7% when a multiplex PCR preamplification step was added. We then tested stored Mycobacterium tuberculosis-positive stained smears prepared from 297 patients' sputum samples. Species identification and drug susceptibility testing (DST) had been performed at the Institut Pasteur de Madagascar. Overall, the performance of the MTBDRplus assay applied to slide DNA was similar to that obtained in other studies with DNA extracted from clinical specimens. With the ready availability of stained smears in routine diagnostic laboratories and their easy transport and storage at room temperature, this approach should be useful for optimizing the treatment of multidrug-resistant tuberculosis and for conducting resistance surveys aimed at identifying hot-spot regions and breaking chains of transmission.
authors.affiliation: Institut Pasteur de Madagascar, Ambatofotsikely BP 1274, Antananarivo, Madagascar.
authors.forename: Natasha
authors.initials: N
authors.lastname: Dubois Cauwelaert
authors.forename: Herimanana
authors.initials: H
authors.lastname: Ramarokoto
authors.forename: Pascaline
authors.initials: P
authors.lastname: Ravololonandriana
authors.forename: Vincent
authors.initials: V
authors.lastname: Richard
authors.forename: Voahangy
authors.initials: V
authors.lastname: Rasolofo
mesh_terms: D000995:Antitubercular Agents; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D024881:Drug Resistance, Bacterial; D006801:Humans; D007538:Isoniazid / Q000494:pharmacology; D008826:Microbial Sensitivity Tests / Q000379:methods; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics*; D012293:Rifampin / Q000494:pharmacology; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D013183:Sputum / Q000382:microbiology*
chemical_list: D000995:Antitubercular Agents; D004269:DNA, Bacterial; D007538:Isoniazid; D012293:Rifampin