Dataset Information

Genetic variability and consequence of Mycobacterium tuberculosis lineage 3 in Kampala-Uganda.

ABSTRACT:

Background

Limited data existed exclusively describing Mycobacterium tuberculosis lineage 3 (MTB-L3), sub-lineages, and clinical manifestations in Kampala, Uganda. This study sought to elucidate the circulating MTB-L3 sub-lineages and their corresponding clinical phenotypes.

Method

A total of 141 M. tuberculosis isolates were identified as M. tuberculosis lineage 3 using Single nucleotide polymorphism (SNP) marker analysis method. To ascertain the sub-lineages/sub-strains within the M. tuberculosis lineage 3, the direct repeat (DR) loci for all the isolates was examined for sub-lineage specific signatures as described in the SITVIT2 database. The infecting sub-strains were matched with patients' clinical and demographic characteristics to identify any possible association.

Result

The data showed 3 sub-lineages circulating with CAS 1 Delhi accounting for 55% (77/141), followed by CAS 1-Kili 16% (22/141) and CAS 2/CAS 8% (12/141). Remaining isolates 21% (30/141) were unclassifiable. To explore whether the sub-lineages differ in their ability to cause increased severe disease, we used extent of lung involvement as a proxy for severe disease. Multivariable analysis showed no association between M. tuberculosis lineage 3 sub-lineages with severe disease. The risk factors associated with severe disease include having a positive smear (OR = 9.384; CI 95% = 2.603-33.835), HIV (OR = 0.316; CI 95% = 0.114-0.876), lymphadenitis (OR = 0. 171; CI 95% = 0.034-0.856) and a BCG scar (OR = 0.295; CI 95% = 0.102-0.854).

Conclusion

In Kampala, Uganda, there are three sub-lineages of M. tuberculosis lineage 3 that cause disease of comparable severity with CAS-Dehli as the most prevalent. Having HIV, lymphadenitis, a BCG scar and a smear negative status is associated with reduced severe disease.

SUBMITTER: Wampande EM

PROVIDER: S-EPMC6733460 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Genetic variability and consequence of Mycobacterium tuberculosis lineage 3 in Kampala-Uganda.

Wampande Eddie M EM Naniima Peter P Mupere Ezekiel E Kateete David P DP Malone LaShaunda L LL Stein Catherine M CM Mayanja-Kizza Harriet H Gagneux Sebastien S Boom W Henry WH Joloba Moses L ML

PloS one 20190909 9

<h4>Background</h4>Limited data existed exclusively describing Mycobacterium tuberculosis lineage 3 (MTB-L3), sub-lineages, and clinical manifestations in Kampala, Uganda. This study sought to elucidate the circulating MTB-L3 sub-lineages and their corresponding clinical phenotypes.<h4>Method</h4>A total of 141 M. tuberculosis isolates were identified as M. tuberculosis lineage 3 using Single nucleotide polymorphism (SNP) marker analysis method. To ascertain the sub-lineages/sub-strains within t ...[more]

PMID: 31498808

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Dataset Information

Genetic variability and consequence of Mycobacterium tuberculosis lineage 3 in Kampala-Uganda.

Background

Method

Result

Conclusion

Publications

Genetic variability and consequence of Mycobacterium tuberculosis lineage 3 in Kampala-Uganda.

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