title: Evaluation of the MeltPro TB/STR assay for rapid detection of streptomycin resistance in Mycobacterium tuberculosis.
abstract: Rapid and comprehensive detection of drug-resistance is essential for the control of tuberculosis, which has facilitated the development of molecular assays for the detection of drug-resistant mutations in Mycobacterium tuberculosis. We hereby assessed the analytical and clinical performance of an assay for streptomycin-resistant mutations. MeltPro TB/STR is a closed-tube, dual-color, melting curve analysis-based, real-time PCR test designed to detect 15 streptomycin-resistant mutations in rpsL 43, rpsL 88, rrs 513, rrs 514, rrs 517, and rrs 905-908 of M. tuberculosis. Analytical studies showed that the accuracy was 100%, the limit of detection was 50-500 bacilli per reaction, the reproducibility in the form of Tm variation was within 1.0 °C, and we could detect 20% STR resistance in mixed bacterial samples. The cross-platform study demonstrated that the assay could be performed on six models of real-time PCR instruments. A multicenter clinical study was conducted using 1056 clinical isolates, which were collected from three geographically different healthcare units, including 709 STR-susceptible and 347 STR-resistant isolates characterized on Löwenstein-Jensen solid medium by traditional drug susceptibility testing. The results showed that the clinical sensitivity and specificity of the MeltPro TB/STR was 88.8% and 95.8%, respectively. Sequencing analysis confirmed the accuracy of the mutation types. Among all the 8 mutation types detected, rpsL K43R (AAG → AGG), rpsL K88R (AAG → AGG) and rrs 514 A → C accounted for more than 90%. We concluded that MeltPro TB/STR represents a rapid and reliable assay for the detection of STR resistance in clinical isolates.
authors.affiliation: The State Key Laboratory of Cellular Stress Biology, Engineering Research Center of Molecular Diagnostics, Ministry of Education, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
authors.affiliation: The State Key Laboratory of Cellular Stress Biology, Engineering Research Center of Molecular Diagnostics, Ministry of Education, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China.
authors.forename: Siyu
authors.initials: S
authors.lastname: Hu
authors.affiliation: Institute for Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing 100091, China.
authors.forename: Guoli
authors.initials: G
authors.lastname: Li
authors.affiliation: Tuberculosis Reference Laboratory, Henan Center for Disease Control and Prevention, Zhengzhou, Henan 450016, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Pathological Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liu
authors.affiliation: Zhongshan Hospital Xiamen University, Xiamen, Fujian 361005, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Niu
authors.affiliation: Department of Pathological Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: Division of Tuberculosis Prevention, Xiamen Center for Disease Control and Prevention, Xiamen, Fujian 361021, China.
authors.forename: Huixin
authors.initials: H
authors.lastname: Wen
authors.affiliation: The State Key Laboratory of Cellular Stress Biology, Engineering Research Center of Molecular Diagnostics, Ministry of Education, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China. Electronic address: xuye@xmu.edu.cn.
authors.forename: Ye
authors.initials: Y
authors.lastname: Xu
authors.affiliation: The State Key Laboratory of Cellular Stress Biology, Engineering Research Center of Molecular Diagnostics, Ministry of Education, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361102, China. Electronic address: qgli@xmu.edu.cn.
authors.forename: Qingge
authors.initials: Q
authors.lastname: Li
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D003429:Cross Reactions; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D009154:Mutation; D009161:Mycobacterium / Q000145:classification; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D013307:Streptomycin / Q000494:pharmacology*; D044366:Transition Temperature; D014376:Tuberculosis / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents; D013307:Streptomycin
keywords: Evaluation; Melting curve analysis; Mycobacterium tuberculosis; Real-time PCR; Streptomycin