Wattana CheunoyMelles HaileAngkana ChaiprasertTherdsak PrammanananMariana Cristea-FernstrÖmMartin VondracekErja ChryssanthouSven HoffnerBjörn PetriniSwedish Institute for Infectious Disease ControlKarolinska University HospitalMahidol UniversityThailand National Center for Genetic Engineering and Biotechnology2018-09-132018-09-132009-04-01APMIS. Vol.117, No.4 (2009), 286-29016000463090346412-s2.0-63449117430https://repository.li.mahidol.ac.th/handle/20.500.14594/28135Cheunoy W, Haile M, Chaiprasert A, Prammananan T, Cristea-Fernström M, Vondracek M, Chryssanthou E, Hoffner S, Petrini B. Drug resistance and genotypic analysis of Mycobacterium tuberculosis strains from Thai tuberculosis patients. APMIS 2009; 117: 286-90. The aim of this study was the molecular characterization of primary drug-resistant Mycobacterium tuberculosis strains in Thailand. We examined a group of M. tuberculosis isolates from newly registered tuberculosis (TB) cases, collected at the largest university hospital, the Siriraj Hospital, in Thailand. Of 76 selected drug-resistant M. tuberculosis strains recovered from previously untreated pulmonary TB patients whose sputum samples were sent to this hospital, 29 (38%) were single-drug resistant, 26 (34%) multidrug resistant and two (2.6%) extensively drug resistant. Fifty (66%) strains belonged to Beijing genotype. The study demonstrate a severe problem of drug resistance among recently detected TB patients, and two large clusters of genetically similar strains indicated ongoing transmission of drug-resistant TB. © 2009 APMIS.Mahidol UniversityMedicineArticleSCOPUS10.1111/j.1600-0463.2009.02438.x