The Union World Conference on Lung Health is the world’s largest and most authoritative annual academic event in the field of tuberculosis and lung health. This year, the 53rd The Union World Conference on Lung Health was held virtually from 8-11, November, 2022. Conference is under the theme Combating Pandemics: Today & Tomorrow, which covers the topics of the prevention, diagnosis and treatment of lung diseases including tuberculosis, along with the discussion on novel drugs and diagnostic methods for tuberculosis.
On the oral abstract sessions on 10 November, under the topic of Susceptibilty Resistance, experts from 7 countries shared their latest studies from different perspectives.
The thin-layer agar method allows a fast determination of the minimal inhibitory concentration for Bedaquiline (Prof Cuella Martin, Institute of Tropical Medicine, Unit of Mycobacteriology, Antwerp, Belgium,)
Phenotypic drug susceptibility profile, genetic determinants of drug resistance and treatment outcomes of newly diagnosed pulmonary tuberculosis patients in two TB Centers, Myanmar (Dr Wah Wah Aung, Advanced Molecular Research Centre, Department of Medical Research, Yangon, Myanmar)
Evaluation of Meltpro® MTB/PZA to detect susceptibility of pyrazinamide among rifampicin-resistance tuberculosis patients (Dr. Sun Feng, Huashan Hospital, Fudan University, Department of Infectious Diseases, Shanghai, China)
Isoniazid resistance-conferring mutations are associated with highly variable phenotypic resistance (Dr. Senamile L Ngema, Centre for the AIDS Programme of Research in South Africa, Medical Microbiology, Durban, South Africa)
Genotype-phenotype profiling of serial isolates in patients receiving bedaquiline for drug-resistant TB (Prof Linrui Tang, Columbia University Mailman School of Public Health, Epidemiology, New York, United States of America)
The simple one step stool processing method to diagnose tuberculosis in children: data from a pilot study in general hospitals in Southern Ethiopia (Prof Yohannes Babo, Tuberculosis Foundation, Program implementation, Addis Ababa, Ethiopia)
Implementation and comprehensive molecular drug resistance profile analysis derived from whole genome sequencing of Mycobacterium tuberculosis in Kazakhstan (Dr. Nurlan Takenov, National Scientific Center for Phthisiopulmonology, National Reference Laboratory, Almaty, Kazakhstan)
The team of Prof Zhang Wenhong from Huashan Hospital, Fudan University, China, and Sun Feng, director of the Clinical Research Department of the National Center for Infectious Diseases, reported the evaluation of Meltpro®MTB/PZA to detect susceptibility of pyrazinamide among rifampicin-resistance tuberculosis patients at this conference. It is believed that Meltpro® MTB/PZA is able to directly detect pyrazinamide molecular resistance from sputum samples. Compared with other methods such as strain sequencing, Meltpro® MTB/PZA obtained results in a shorter time frame, which indicates Meltpro® MTB/PZA can be used as a preliminary screening method to offer a guideline of determining the treatment of tuberculosis in time.
Pyrazinamide (PZA), as an important first-line anti-tuberculosis drug, can kill Mycobacterium tuberculosis in a semi-dormant state in phagocytes . Due to its good effectiveness, it is widely used in the treatment of tuberculosis. However, with the emergence of multidrug-resistant tuberculosis in recent years, PZA resistance has led to treatment failure in some patients. Therefore, routine PZA drug susceptibility testing is extremely important to reduce the occurrence of drug resistance. But pyrazinamide shows antibacterial activity only under low pH conditions, which makes in vitro PZA drug susceptibility test more complicated . Molecular biology methods applied to the diagnosis of PZA drug resistance can quickly obtain results, shorten the course of treatment, and improve the cure rate.
Meltpro®MTB/PZA (Xiamen Zeesan Biotech Co., Ltd.) is a novel method for rapid detection of PZA drug resistance in tuberculosis diagnosis and clinical specimens. Based on the Multicolor Melting Curve Analysis (MMCA®) on real-time PCR platform, adopting the “imbricate” probe arrangement, Meltpro®MTB/PZA achieves the coverage of the full-length 561 bp of the pncA gene and its upstream and downstream potential mutation sites in 3 reaction tubes. In the above study, the sensitivity, specificity and accuracy of Meltpro® MTB/PZA were evaluated using clinical samples from patients with rifampicin-resistant tuberculosis (RR-TB) and next-generation sequencing (NGS) as the reference standard. Meltpro®MTB/PZA was used to test 232 clinical specimens. Mycobacterium tuberculosis was detected in 195 specimens (84.0%). The sensitivity and specificity of this method to detect PZA drug resistance were 88.3% and 89.5%, respectively, and the accuracy was 89.1%. The project is still in the research stage, and more clinical samples will be included in the following evaluation.
ZEESAN has been involved in the field of molecular diagnostics of tuberculosis for decades. It possesses intellectual property rights of Multicolor Melting Curve Analysis (MMCA®). ZEESAN has launched the high-throughput MeltPro® TB integrated detection system and the Sanity®2.0 Fully Automated Medical PCR Analytical System. As the market leader of molecular diagnostics of tuberculosis in China, ZEESAN provides the full range of solutions covering tuberculosis screening, mycobacterial identification, drug susceptibility, personalized medication, strain traceability, etc., to provides a great boost to the rapid diagnosis of mycobacteriosis.
Rapid diagnosis is essential for effective control of drug-resistant TB outbreaks. At present, ZEESAN offers drug-resistance detection workflow covering first-line and second-line anti-tuberculosis drugs. Among them, there are 6 kits, which are CE certified, to test drug-resistance mutations involving the following drugs: rifampicin, isoniazid, fluoroquinolones, ethambutol, streptomycin and second-line injectable drug. With above capabilities, ZEESAN offers the widest range of drug-resistant TB molecular detection solution in the market.
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