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. 2023 Mar 29:2023:3291538.
doi: 10.1155/2023/3291538. eCollection 2023.

Drug Resistance in Tuberculous Lymphadenitis: Molecular Characterization

Gebeyehu Assefa  1   2 , Kassu Desta  2 , Shambel Araya  2 , Selfu Girma  1 , Elena Hailu  1 , Adane Mihret  1 , Tsegaye Hailu  1 , Melaku Tilahun  1 , Getu Diriba  3 , Biniyam Dagne  3 , Abay Atnafu  1 , Nigatu Endalafer  1 , Adugna Abera  3 , Shiferaw Bekele  1 , Yordanos Mengistu  4 , Kidist Bobosha  1 , Abraham Aseffa  1
Affiliations

Drug Resistance in Tuberculous Lymphadenitis: Molecular Characterization

Gebeyehu Assefa et al. Tuberc Res Treat. .

Abstract

Background: Drug-resistant tuberculosis (TB) epidemic in high-TB-incidence countries, particularly Ethiopia, remains a significant challenge. As a result, we investigated the drug resistance, common gene mutation, and molecular characterization of mycobacterial isolates from patients with suspected tuberculous lymphadenitis (TBLN). Methodology. A cross-sectional study of 218 FNA samples from TBLN patients inoculated on Lowenstein-Jensen media was carried out. The culture isolates were identified as MTB by polymerase chain reaction (PCR) and the difference-9 (RD9) test region. In addition, the GenoType MTBDRplus assay tested the first and second-line MTB drugs, and the spoligotyping strain-dependent polymorphism test was determined.

Results: Among the 50 culture-positive isolates, 14% (7/50) had drug resistance caused by a gene mutation. Out of these, 4 (8%) isolates were mono-resistant to isoniazid drug, which is caused by a gene mutation in katG in the region of interrogated at codon 315 in the amino acid sequence of S315T1, and 3 (6%) isolates were resistant to both rifampicin and isoniazid drugs. The mutation was observed for katG (at codon 315 with a change in the sequence of amino acid S315T) and rpoB (at codon 530-533 with a change in the sequence of amino acid S531L (S450L)) genes. The most prevalent spoligotypes were orphan and SIT53 strains.

Conclusion: The predominance of INH mono-resistance poses a critical risk for the potential development of MDR-TB, as INH mono-resistance is a typical pathway to the occurrence of MDR-TB. The orphan and SIT53 (T) strains were the most common in the study area, and a drug-resistant strain caused by a common gene mutation could indicate the transmission of clonal-resistant strains in the community.

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Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Figure 1
Figure 1
Flowchart of the study procedure.
Figure 2
Figure 2
Region of difference 9 (RD-9) of M. tuberculosis strains isolated from TBLN patients from ALERT and St. Peter Specialized Hospital Addis Ababa, Ethiopia (2020).
Figure 3
Figure 3
Spoligotype pattern of M. tuberculosis strains isolated from TBLN patients from ALERT and St. Peter Specialized Hospital Addis Ababa, Ethiopia (2020).
See this image and copyright information in PMC

References

    1. World Health Organization. WHO; 2021. Global tuberculosis report.
    1. Ducomble T., Tolksdorf K., Karagiannis I., et al. The burden of extrapulmonary and meningitis tuberculosis, an investigation of national surveillance data. Germany, 2002 to 2009. Euro Surveillance . 2013;18(12) doi: 10.2807/ese.18.12.20436-en. - DOI - PubMed
    1. World Health Organization. WHO; 2020. Global tuberculosis report.
    1. World Health Organization. WHO Treatment Guidelines for Isoniazid-Resistant Tuberculosis: Supplement to the WHO Treatment Guidelines for Drug-Resistant Tuberculosis . WHO; 2018. - PubMed
    1. Seung K. J., Keshavjee S., Rich M. L. Multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis. Cold Spring Harbor Perspective in Medicine . 2015;5(9, article a017863) doi: 10.1101/cshperspect.a017863. - DOI - PMC - PubMed