Assoc Prof Daniel Mekonnen
Bahir Dar University, Ethiopia
Comparative Whole Genome Sequence Analysis of Mycobacterium tuberculosis Isolated from Pulmonary Tuberculosis and Tuberculous Lymphadenitis Cases in Northwest Ethiopia Genomic Diversity, Transmission Dynamics and In-Silico Molecular Drug Resistance
Poster Abstract
Introduction: The exceptionally high incidence rate of tuberculous lymphadenitis (TBLN) in Ethiopia prompted much investigation.
Objective: The objectives of this study was to identify pathogen and host related factors that could explain why TBLN is exceptionally high in Amhara Regional State.
Methods: The study utilized a combination of DOTS clinic data, laboratory, and genomic approaches to investigate TB in the region, compared hematological and lipid profiles and determine the genomic diversity and drug resistance of Mycobacterium tuberculosis complex (MTBC) strains using whole genome sequencing.
Results: The finding showed that the mean annual incidence rate of TBLN was 47.5%. Extra Pulmonary Tuberculosis (EPTB) was higher in females and in rural Woredas. The spatial analysis showed that EPTB radiated from west Amhara to eastward forming, EPTB belt of Amhara. The mean body mass index (BMI), CD4+T cell count and high-density Lipoprotein-Cholesterol (HDL-C) values were significantly higher among TBLN cases compared with PTB cases. 146 Mtbc isolates were successfully genotyped into 3 lineages and 18 sub-lineages. There was no lineage and sub-lineage difference between PTB and TBLN. However, at the threshold of ≤ 5 neucleotide/allelic differences, the presence of genetic variation was observed among Mtb isolates obtained from PTB and TBLN cases. The high rate of recent transmission index for TBLN cases (18%) compared with PTB (15%) indicated the severity of TBLN epidemics and rate of rapid clinical progression from primary infection. Mtb sub-lineage L4.2.2.ETH was the leading drug resistance clone.
Conclusion and recommendations: The high incidence rate of TBLN in Amhara region could be explained with strain genetic difference. Further study is warranted to validate this finding and reinforce the conclusion.
Biography
My research area is genomic epidemiology, infection biology, drug resistance, and bioinformatics of M .tuberculosis (MTB). The overall goal of the project is to obtain mechanistic insight into the clinical evolution of the different forms of TB leading to a better understanding of the immunologic landscape of MTB, which again leads to vaccine development. Further, I am very interested in BCG revaccination in adolescents and adults in high-transmission settings.