title: Application of genotype MTBDRplus in rapid detection of the Mycobacterium tuberculosis complex as well as its resistance to isoniazid and rifampin in a high volume laboratory in Southern China.
abstract: The alarmingly worsening epidemics of drug-resistant tuberculosis (TB) call urgent need for a simple method for the rapid detection of drug-resistant TB in clinical settings. In an attempt to establish a rapid procedure for laboratory diagnosis of TB and investigate the local TB epidemiology, molecular line probe assay of the Genotype MTBDRplus was used to identify Mycobacterium tuberculosis complex (MTBC) and detect mutations conferring resistance to two most active first-line drugs against TB: Rifampin and Isoniazid. 96 acid-fast bacillus (AFB) smear- positive sputums and 18 PCR-positive non-sputum specimens have been determined for the MTBC and resistance to Rifampin and Isoniazid. The MTBC detection rates in two sources of specimens were 93.8% (90/96) and 77.8% (14/18) respectively. The overall drug resistance (Rifampin or Isoniazid) occurred in 34.6% (36/104). Resistance to rifampin (RMP) was 28.8% (30/104) and 25% (26/104) was to Isoniazid (INH), in which high level drug resistance accounted for 88.5% (23/26) and low level drug resistance accounted for 7.7% (2/26). Multidrug resistance (MDR), defined as resistant to both RMP and INH, was found in 19.2% (20/104) of clinical samples, which was double that of official statistics. In addition, 63.3% (19/30) RMP-resistant mutations were identified in the region of RopB 530-533 and 57.9% (11/19) were the S531L mutation. 84.6% (22/26) of resistance to INH was mediated by Kat S315T1 mutations which conferred the high-level resistance to INH. The Genotype MTBDRplus line probe assay is a suitable and applicable method for establishing the rapidness in detection of drug-resistant TB in clinical laboratory. It will be a valuable addition to the conventional TB diagnostic approaches.
authors.affiliation: Department of Laboratory Medicine, West China Hospital of Sichuan University, 37 Guoxue Alley, Chengdu, 610041 Sichuan Province, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Yuanxing
authors.initials: Y
authors.lastname: Ye
authors.forename: Lina
authors.initials: L
authors.lastname: Duo
authors.forename: Tingting
authors.initials: T
authors.lastname: Wang
authors.forename: Xingbo
authors.initials: X
authors.lastname: Song
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Lu
authors.forename: Binwu
authors.initials: B
authors.lastname: Ying
authors.forename: Lanlan
authors.initials: L
authors.lastname: Wang
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology; D020029:Base Pairing / Q000235:genetics; D002681:China / Q000453:epidemiology; D019411:Clinical Laboratory Techniques; D015342:DNA Probes / Q000378:metabolism; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects* / Q000235:genetics; D004587:Electrophoresis, Agar Gel; D005798:Genes, Bacterial / Q000235:genetics; D005838:Genotype; D006801:Humans; D007538:Isoniazid / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009154:Mutation / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification*; D009693:Nucleic Acid Hybridization / Q000379:methods*; D016133:Polymerase Chain Reaction; D011933:Reagent Kits, Diagnostic; D012293:Rifampin / Q000494:pharmacology*; D018088:Tuberculosis, Multidrug-Resistant / Q000453:epidemiology / Q000235:genetics / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents; D015342:DNA Probes; D011933:Reagent Kits, Diagnostic; D007538:Isoniazid; D012293:Rifampin