European Society of Mycobacteriology - Instituto Nacional de Saúde ...

op-7
Mycobacterium tuberculosis genetic diversity in South Korea
Isdore Chola Shamputa 1 , Jongseok Lee 2 , Caroline Allix-Béguec 3 , Eun-Jin Cho 2 , Ji-im Lee 2 , Jin Hong Min 4 ,
Lisa C. Goldfeder 1 , Jin Hee Kim 4 , Hyung Seok Kang 4 , Soo Hee Hwang 4 , Seok Yong Eum 2 ,Hyeyoung
Lee 5 , Seung Kyu Park 2,4 , Philip Supply 3,6 , Sang Nae Cho 7 , Laura E. Via 1 , Clifton E. Barry III 1
1 - Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health,
Bethesda, Maryland
2 - International Tuberculosis Research Center, Masan South Korea
3 - Genoscreen, Lille, France
4 - Masan National Tuberculosis Hospital, Masan, South Korea
5 - Department of Biomedical Laboratory Sciences, Yonsei University, Wonju, South Korea
6 - Centre National de la Recherche Scientifique, Institut Pasteur de Lille/Institut de Biologie de Lille, Lille France
7 - Department of Microbiology, Yonsei University College of Medicine, South Korea
South Korea has recorded a nine fold decrease in the incidence of TB in the last four decades, however challenges of TB
control remain significant as the Republic of Korea is among the 30 countries with the highest numbers of estimated
MDR-TB cases. Genotypic analysis of M. tuberculosis has greatly contributed to the control of TB by providing information
on transmission dynamics, assessing clonal distribution and expansion of the tubercle bacilli, in investigating of outbreaks
and pseudo-outbreaks, and in identifying laboratory cross contamination. However, there is limited information on the
molecular epidemiology of TB in South Korea.
Genetic diversity of 208 M. tuberculosis isolates from subjects enrolled in a prospective observational cohort study at
National Masan Tuberculosis Hospital in South Korea was determined using spoligotyping, IS6110-RFLP and standardised
MIRU-VNTR typing based on 24 loci. MIRU-VNTR analysis was performed independently and blindly from spoligotyping
and IS6110-RFLP results.
Analysis of MIRU-VNTR typing results use in conjunction with MIRU-VNTRplus database predicted that 202 (97.1%)
isolates belonged to the Beijing genotype. This prediction was fully confirmed by spoligotyping. Congruence analysis indicated
the prevalence of 3 branches among Beijing strains respectively named Korea, Masan and China. Preliminary analysis
did not show differential distribution of resistant, MDR or XDR strains among the 3 branches. MDR or XDR isolates
were detected in at least 4 clusters concordantly identified by the 3 genotyping methods. Using MIRU-VNTR typing and
spoligotyping, 23 clusters of 66 isolates were detected indicating a relatively large diversity of circulating strains despite
the prevalence of the Beijing lineage.
Standardised MIRU-VNTR typing appeared efficient as a first line discriminatory method for this country with high
prevalence of Beijing strains. However, preliminary analyses suggest that clustered cases may not be epidemiologically
linked and rather correspond to endemic strains circulating in South Korea.
European Society of Mycobacteriology | 30 th Annual Congress | July 2009 | Porto - Portugal
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