Siti Suraiya
Universiti Sains Malaysia, Malaysia
Title: Molecular diversity of Mycobacterium tuberculosis complex isolated from pulmonary tuberculosis cases in Malaysia
Biography
Biography: Siti Suraiya
Abstract
Background: Tuberculosis (TB) still constitutes a major public health problem in Malaysia. The identification and genotyping based characterization of Mycobacterium tuberculosis complex (MTBC) isolates causing the disease is important to determine the effectiveness of the control and surveillance programs.
Objectives: This study intended a first assessment of spoligotyping-based MTBC genotypic diversity in Malaysia followed by a comparison of strains with those prevailing in neighboring countries by comparison with an international MTBC genotyping database.
Methods: Spoligotyping was performed on a total of 220 M. tuberculosis clinical isolates collected in Kelantan and Kuala Lumpur. The results were compared with the SITVIT2 international database Results: Spoligotyping revealed 77 different patterns: 22 corresponded to orphan patterns while 55 patterns containing 198 isolates were assigned a Spoligo International Type (SIT) designation in the database (the latter included 6 newly created SITs). The eight most common SITs grouped 141 isolates (5 to 56 strains per cluster) as follows: SIT1/Beijing, n=56, 25.5%; SIT745/EAI1-SOM, n=33, 15.0%; SIT591/EAI6-BGD1, n=13, 5.9%; SIT256/EAI5, n=12, 5.5%; SIT236/EAI5, n=10, 4.6%; SIT19/EAI2-Manila, n=9, 4.1%; SIT89/EAI2-Nonthaburi, n=5, 2.3%; and SIT50/H3, n=3, 1.4%. The association between city of isolation and lineages was statistically significant; Haarlem and T lineages being higher in Kuala Lumpur (p<0.01). However, no statistically significant differences were noted when comparing drug resistance vs. major lineages, nor between gender and clades.
Conclusions: The ancestral East-African-Indian (EAI) lineage was most predominant followed by the Beijing lineage. A comparison of strains with those prevailing in neighboring countries in South Asia, East Asia and South East Asia underlined the phylogeographical specificity of SIT745 for Malaysia, and its probable ongoing evolution.