Proposal of a new method for subtyping of Mycobacterium kansasii based upon PCR restriction enzyme analysis of the tuf gene

Within this study, a new, rapid method for subtyping of Mycobacterium kansasii was developed based on the sequence analysis of the tuf gene coding for the Tu (thermo-unstable) elongation factor (EF-Tu). The method involves PCR amplification of ca. 740-bp tuf gene fragment, followed by digestion with the MvaI restriction endonuclease

Clinical, radiological and molecular features of Mycobacterium kansasii pulmonary disease

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Draft Genome Sequences of Mycobacterium kansasii Clinical Strains

Mycobacterium kansasii is a nontuberculous mycobacterial (NTM) pathogen, frequently isolated from clinical samples and responsible for a large part of NTM infections in the human population. Here, we report the draft genome sequences of 12 M. kansasii strains isolated from clinical and host-associated sources from the Netherlands, Germany, and Poland

Drug Susceptibility Profiling and Genetic Determinants of Drug Resistance in Mycobacterium kansasii

Item does not contain fulltextVery few studies have examined drug susceptibility of Mycobacterium kansasii, and they involve a limited number of strains. The purpose of this study was to determine drug susceptibility profiles of M. kansasii isolates representing a spectrum of species genotypes (subtypes) with two different methodologies, i.e., broth microdilution and Etest assays. To confirm drug resistance, drug target genes were sequenced. A collection of 85 M. kansasii isolates, including representatives of eight different subtypes (I to VI, I/II, and IIB) from eight countries, was used. Drug susceptibility against 13 and 8 antimycobacterial agents was tested by using broth microdilution and Etest, respectively. For drug-resistant or high-MIC isolates, eight structural genes (rrl, katG, inhA, embB, rrs, rpsL, gyrA, and gyrB) and one regulatory region (embCA) were PCR amplified and sequenced in the search for resistance-associated mutations. All isolates tested were susceptible to rifampin (RIF), amikacin (AMK), co-trimoxazole (SXT), rifabutin (RFB), moxifloxacin (MXF), and linezolid (LZD) according to the microdilution method. Resistance to ethambutol (EMB), ciprofloxacin (CIP), and clarithromycin (CLR) was found in 83 (97.7%), 17 (20%), and 1 (1.2%) isolate, respectively. The calculated concordance between the Etest and dilution method was 22.6% for AMK, 4.8% for streptomycin (STR), 3.2% for CLR, and 1.6% for RIF. For EMB, INH, and SXT, not even a single MIC value determined by one method equaled that by the second method. The only mutations disclosed were A2266C transversion at the rrl gene (CLR-resistant strain) and A128G transition at the rpsL gene (strain with STR MIC of >64 mg/liter). In conclusion, eight drugs, including RIF, CLR, AMK, SXT, RFB, MXF, LZD, and ethionamide (ETO), showed high in vitro activity against M. kansasii isolates. Discrepancies of the results between the reference microdilution method and Etest preclude the use of the latter for drug susceptibility determination in M. kansasii Drug resistance in M. kansasii may have different genetic determinants than resistance to the same drugs in M. tuberculosis