Rapid detection of non-rifampicin resistant drug-resistant tuberculosis using Xpert MTB/XDR testing: Findings from a multisite drug-resistant tuberculosis case detection surge in Zambia

@article{mwaba2026rapid,
  title = {{Rapid detection of non-rifampicin resistant drug-resistant tuberculosis using Xpert MTB/XDR testing: Findings from a multisite drug-resistant tuberculosis case detection surge in Zambia}},
  author = {Phallon Blessing Mwaba and Marshal Sikandangwa and Robertson Chibumbya and Innocent Mwaba and Minyoi Mubita Maimbolwa and Chitalu Chanda and Muhammad Mputu and Rhehab Chimzizi and Kevin Mabvuto Zimba and Nancy Kasese Chanda and Angel Mubanga and Monde Muyoyeta and Mary Kagujje},
  journal = {PLOS Global Public Health},
  year = {2026},
  month = sep,
  doi = {10.1371/journal.pgph.0005536},
  url = {https://journals.plos.org/globalpublichealth/article?id=10.1371/journal.pgph.0005536},
  note = {CC BY 4.0},
}

TY  - JOUR
TI  - Rapid detection of non-rifampicin resistant drug-resistant tuberculosis using Xpert MTB/XDR testing: Findings from a multisite drug-resistant tuberculosis case detection surge in Zambia
AU  - Phallon Blessing Mwaba
AU  - Marshal Sikandangwa
AU  - Robertson Chibumbya
AU  - Innocent Mwaba
AU  - Minyoi Mubita Maimbolwa
AU  - Chitalu Chanda
AU  - Muhammad Mputu
AU  - Rhehab Chimzizi
AU  - Kevin Mabvuto Zimba
AU  - Nancy Kasese Chanda
AU  - Angel Mubanga
AU  - Monde Muyoyeta
AU  - Mary Kagujje
PY  - 2026
DA  - 2026/09/23
JO  - PLOS Global Public Health
DO  - 10.1371/journal.pgph.0005536
UR  - https://journals.plos.org/globalpublichealth/article?id=10.1371/journal.pgph.0005536
AB  - Zambia continues to face a high-Tuberculosis burden with rising drug resistance, yet diagnosis of non-rifampicin resistant drug-resistance remains limited due to reliance on rifampicin as a proxy for multidrug-resistant tuberculosis. The Xpert MTB/XDR assay offers a rapid detection of resistance to isoniazid, fluoroquinolone, Ethionamide and aminoglycosides, addressing a major diagnostic gap. The aim of this analysis was to describe the prevalence and profile of drug resistance among bacteriologically confirmed TB patients subjected to reflex Xpert MTB/XDR testing. We conducted an analysis of programmatic data from a four-week active drug-resistant TB case finding surge in May 2025, implemented across 39 high-TB burden facilities in five provinces of Zambia. We re-evaluated eligible Xpert MTB/RIF Ultra positive TB patients using the Xpert MTB/XDR platform regardless of Rifampicin resistance to identify additional drug resistance beside rifampicin. We analyzed patient demographics, characteristics, and the distribution of drug resistance drug-resistance categories descriptively. Of 509 TB patients identified, 70.9%(n = 360) were bacteriologically confirmed by Xpert MTB/RIF Ultra among whom 92.8%(n = 336) were eligible for reflex Xpert MTB/XDR testing. Of the eligible, 89.3% (n = 313) underwent reflex Xpert MTB/XDR testing. Results were successfully retrieved for 282 (90.1%). Overall, 8.5%(n = 24) of patients with XDR results had a form of drug-resistant tuberculosis. Mono-resistance to rifampicin (3.5%, n = 10) or isoniazid (3.2%, n = 9) was more prevalent than multi-drug-resistant tuberculosis (1.1%, n = 3), while only 0.4% (n = 1) had Pre-XDR TB. Non-rifampicin resistant drug-resistance, including isoniazid mono-resistance and isoniazid combined with fluoroquinolone or ethionamide resistance, were detected in 3.2% (n = 9) of all patients with XDR TB results (37.5% of all DR-TB cases). Reflex Xpert MTB/XDR testing enabled rapid identification of non-rifampicin-resistance drug-resistant TB cases that would have been missed by rifampicin-centric diagnostics. Strengthening the integration of MTB/XDR into routine diagnostic algorithms can improve early drug-resistant tuberculosis detection, guide individualized treatment, and prevent amplification of resistance in high-burden settings.
SN  - 2767-3375
ER  -