Second-line drug resistance among multidrug-resistant tuberculosis patients in Ethiopia: A laboratory-based
Getu Diriba1, Ayinalem Alemu2, Bazezew Yenew1
1Ethiopian Public Health Institute, Addis Ababa, Ethiopia.
Objectives:
To estimate the proportion of second-line anti-tuberculosis drug resistance among multidrug-resistant tuberculosis (MDR-TB) patients in Ethiopia.
Methodology:
A laboratory-based prospective cross-sectional study was conducted at the National Tuberculosis Reference Laboratory (NTRL), Ethiopia, from February 2022 to July 2024. Phenotypic drug susceptibility testing (pDST) assessed resistance to various second-line antituberculosis drugs. The collected data were entered into Microsoft Excel 2016 and imported into Statistical Package for Social Sciences (SPSS) version 23 for descriptive analysis.
Result:
Of 468 MDR-TB patients, 262 were new, and 206 were previously treated cases. Pre-extensively drug-resistant tuberculosis (pre-XDR-TB) was identified in four (1.52%) new cases and seven (3.40%) previously treated cases. Extensively drug-resistant tuberculosis (XDR-TB) was detected in three (1.15%) new cases and two (0.97%) previously treated cases. Overall, 11 (2.35%) cases were classified as pre-XDR-TB, and five (1.07%) as XDR-TB. Combined resistance to fluoroquinolones (FQs) and bedaquiline were detected in four cases (0.85%), comprising three new cases (1.15%) and one previously treated case (0.49%). Resistance to both FQs and linezolid was detected in a single previously treated case (0.49%) and acquired resistance to second-line drugs was identified in four cases.
Conclusions:
Our study showed a prevalence of 2.35% for pre-XDR-TB and 1.07% for XDR-TB among MDR-TB cases, highlighting the importance of continuous surveillance and tailored treatment approaches to control the spread of drug-resistant TB (DR-TB) in Ethiopia. Future studies on MDR-TB surveillance should prioritize the integration of genomic surveillance into routine laboratory-based DR-TB monitoring systems to enhance early detection of resistance patterns, support targeted treatment strategies, and improve overall patient management efforts.
Related Concept Videos
Pulmonary Tuberculosis V
Latent tuberculosis infection occurs when TB bacteria are present in a person's body, but are not causing illness or symptoms. It is not contagious, and preventive treatment is crucial to avoid the...
Treatment Resistant Cancers
Pulmonary Tuberculosis I
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
Pulmonary Tuberculosis IV
Several diagnostic approaches are used to detect TB. The conventional method is the Tuberculin Skin Test (TST), also known as the Mantoux test. However, this method has...
Pulmonary Tuberculosis III
The first classification is based on the development of the disease, and it includes the following categories:


