Genotype distribution of Mycobacterium tuberculosis in theAegean Region and associated demographic factors

Authors: CENGİZ ÇAVUŞOĞLU, FETHİYE FERDA YILMAZ, İSABEL RAİKA DURUSOY ONMUŞ, TUĞBA BOZDEMİR, HÜSEYİN TAŞLI, MİNE HOŞGÖR LİMONCU

Abstract: Background/aim: The Aegean Region is the second-ranking region in Turkey according to the Human Development Index and population density and it hosts 1/8 of Turkey's population. İzmir is the largest city of the region, receiving internal migration both from inside and outside the region. The tuberculosis incidence in İzmir is lower than overall in Turkey: 17.7/100,000 in 2011. Our aims were to determine genotypes of Mycobacterium tuberculosis isolates; to explore possible associations between genotypes with case-demographic data, clinical presentation, and antimicrobial susceptibility patterns; and to determine variations in genotype distribution of strains isolated in Ege University Hospital, İzmir. Materials and methods: Forty-nine M. tuberculosis isolates from 49 patients in 1996-2000 and 421 M. tuberculosis isolates from 421 patients in 2009-2014 were spoligotyped. Drug susceptibility testing and demographic data of the 421 isolates were investigated. Chi-square, Student's t, and Mann-Whitney U tests were used for analyses. Results: Among the 470 M. tuberculosis strains, 132 different spoligopatterns were identified and 46 different clusters for 384 strains were determined. The most predominant spoligotypes were ST53 (n = 116; 24.7%) and ST41 (n = 38; 8.1%), followed by ST50 (5.7%), ST284 (4.7%), and ST4 (4.3%), respectively. ST53 was the most predominant type in both sexes. Multidrug resistance (MDR) was determined in 12 isolates, of which six were ST1.Conclusion: As a consequence of worldwide migration and increasing status of HIV-infected hosts, the increasing prevalence of Beijing strains with higher MDR rates may threaten disease control programs. With its increasing trend, ST284 could replace ST41 in the following years in this region.

Keywords: Spoligotyping, Mycobacterium tuberculosis, genetic diversity, tuberculosis epidemiology

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