Time to Sputum Culture Conversion and Associated Factors in Multidrug-Resistant Tuberculosis Patients in Niger

Yacouba Abdourahamane; Abdou Natali Bassirou; Ounoussa Tapha; Moussa Abdoul-Nasser; Souleymane Bassirou; Moussa Saley Sahada; Soumana Alphazazi; Adam Mamoudou; Saidou Mamadou

doi:10.4167/jbv.2025.55.4.370

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2025 Vol.55, Issue 4 Preview Page

Original Article

Time to Sputum Culture Conversion and Associated Factors in Multidrug-Resistant Tuberculosis Patients in Niger

31 December 2025. pp. 370-381

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Abstract

Background: Culture conversion is a key indicator for monitoring the success of treatment in patients with multidrug-resistant tuberculosis (MDR-TB), and enables the daily dose of drugs to be adjusted. This study aimed to determine the sputum culture conversion time of MDR-TB patients and their related factors in Niger. Methodology: A retrospective study was conducted among MDR-TB patients from 2008 to 2020. GeneXpert, culture, and drug susceptibility tests were performed for each patient. A multivariate logistic analysis was performed to determine factors associated with sputum culture conversion. A p-value < 0.05 was considered significant. Results: A total of 517 patients with MDR-TB followed up in various MDR-TB units in Niger were included. These patients consisted of 83.2% males with a mean age of 34±11.8 years. The frequency of culture conversion after initiation of treatment was 92.8%, with 15.7% in the 1st month and 64.9% in the 2nd month. In multivariate logistic analysis, the predictive factors positively associated with delayed culture conversion were age over 40 years (odds ratio = 3.70; 95% CI: 1.47 - 9.60; p=0.006), death (odds ratio =30.13; 95% CI: 10.61 - 96.72; p<0.001), and resistance to ofloxacin 800 mg (odds ratio =26.37; 95% CI: 6.72 – 108.00; p<0.001). Conclusion: This study underscored a relatively high rate of culture conversion during the intensive phase of treatment among patients with MDR-TB in Niger. High age, death, and ofloxacin resistance were identified as risk factors for delayed culture conversion. These results suggest that early intervention in MDR-TB patients can lead to sputum culture conversion and treatment success.

Keywords

Mycobacterium tuberculosis

Culture

Niger

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Information

Publisher :The Korean Society for Microbiology and The Korean Society of Virology
Publisher(Ko) :대한미생물학회‧대한바이러스학회
Journal Title :JOURNAL OF BACTERIOLOGY AND VIROLOGY
Volume : 55
No :4
Pages :370-381
Received Date : 2025-06-19
Revised Date : 2025-09-27
Accepted Date : 2025-10-16
DOI :https://doi.org/10.4167/jbv.2025.55.4.370

JOURNAL OF BACTERIOLOGY AND VIROLOGY ISSN:1598-2467(Print) 2093-0429(Online)

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