title: Detection of streptomycin and quinolone resistance in Mycobacterium tuberculosis by a low-density DNA array.
abstract: In cases of multidrug-resistant tuberculosis, it is crucial to rule out resistance to second-line antituberculous (anti-TB) agents. In the present study, a low-cost low-density DNA array including four genetic regions (rrs 530 loop, rrs 1400, rpsL and gyrA) was designed for the rapid detection of the most important mutations related to anti-TB injectable drugs (mainly streptomycin) and fluoroquinolone resistance (LD-SQ array). A total of 108 streptomycin- and/or ofloxacin-resistant and 20 streptomycin- and ofloxacin-susceptible Mycobacterium tuberculosis clinical isolates were analysed with the array. The results obtained were compared with sequencing data and phenotypic susceptibility pattern. The LD-SQ array offered a good sensitivity compared to sequencing, especially among resistant strains: 92.5% (37/40) for streptomycin and 87.5% (7/8) for fluoroquinolones. Therefore, this array could be considered a good approach for the rapid detection of mutations related to streptomycin and fluoroquinolone resistance. On the other hand, there were discordant results in 16 resistant strains and six susceptible isolates, mostly concerning the gyrA region, in which the existence of polymorphisms next to informative positions might cause cross-hybridization. These discrepancies were caused by some technical limitations; consequently, the present array should be considered as a first-step prior to a forthcoming optimized version of the array.
authors.affiliation: Servei de Microbiologia, Hospital Universitari de Bellvitge-IDIBELL, Universitat de Barcelona UB, Barcelona, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Moure
authors.forename: Griselda
authors.initials: G
authors.lastname: Tudó
authors.forename: Rebeca
authors.initials: R
authors.lastname: Medina
authors.forename: Eva
authors.initials: E
authors.lastname: Vicente
authors.forename: José María
authors.initials: JM
authors.lastname: Caldito
authors.forename: Maria Gemma
authors.initials: MG
authors.lastname: Codina
authors.forename: Pere
authors.initials: P
authors.lastname: Coll
authors.forename: Montserrat
authors.initials: M
authors.lastname: Español
authors.forename: Julian
authors.initials: J
authors.lastname: Gonzalez-Martin
authors.forename: Emma
authors.initials: E
authors.lastname: Rey-Jurado
authors.forename: Margarita
authors.initials: M
authors.lastname: Salvadó
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Tórtola
authors.forename: Fernando
authors.initials: F
authors.lastname: Alcaide
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D004252:DNA Mutational Analysis / Q000379:methods; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D013307:Streptomycin / Q000494:pharmacology*; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents; D004269:DNA, Bacterial; D024841:Fluoroquinolones; D013307:Streptomycin
keywords: Drug resistance; Fluoroquinolones; LD-SQ array; Mycobacterium tuberculosis; Streptomycin