title: The GenoType® MTBDRplus assay for detection of drug resistance in Mycobacterium tuberculosis in Sweden.
abstract: The performance of the GenoType(®) MTBDRplus assay was compared with conventional drug susceptibility testing (DST) in 604 patients with tuberculosis. The study comprised 477 Mycobacterium tuberculosis complex isolates and 127 preparations of DNA from clinical specimens which had been tested positive for M. tuberculosis by COBAS(®)TaqMan(®) 48. By DST, isoniazid (INH) monoresistance was diagnosed in 56 (9.3%), rifampicin (RMP) monoresistance in 2 (0.3%) and multidrug resistance (MDR) in 21 (3.5%) of the cases. The sensitivity of the MTBDRplus assay was 87.5%, 100% and 95.2% for INH resistance, RMP resistance and MDR respectively. The specificity was 100% for all resistance patterns. The dominating mutations in RMP and INH resistant isolates were in codon 531 of the rpoB gene and codon 315 of the KatG gene. The turnaround time for detection of drug resistance can be shortened from a median of 21 days for DST to 7 days for the MTBDRplus assay. This may have a significant impact on routine work flow of a mycobacteriology laboratory.
authors.affiliation: Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden. erja.chryssanthou@karolinska.se
authors.forename: Erja
authors.initials: E
authors.lastname: Chryssanthou
authors.forename: Kristian
authors.initials: K
authors.lastname: Angeby
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics; D002374:Catalase / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D012321:DNA-Directed RNA Polymerases; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D007538:Isoniazid / Q000494:pharmacology* / Q000627:therapeutic use; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics; D016133:Polymerase Chain Reaction; D012293:Rifampin / Q000494:pharmacology* / Q000627:therapeutic use; D012680:Sensitivity and Specificity; D013548:Sweden / Q000453:epidemiology; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*
chemical_list: D000995:Antitubercular Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C505805:rpoB protein, Mycobacterium tuberculosis; D010088:Oxidoreductases; D002374:Catalase; C480353:katG protein, Mycobacterium tuberculosis; C085257:InhA protein, Mycobacterium; D012321:DNA-Directed RNA Polymerases; D007538:Isoniazid; D012293:Rifampin