Frequency of rifampicin-resistant mycobacterium tuberculosis by GeneXpert MTB/RIF assay and its correlates among 2605 probable tuberculosis patients in upper Egypt

Ebtisam S A Hassanin; Aliae Ar Mohamed Hussein; Shaimaa S Abdelrheem; Ebtehal Dongol; Ahmed Hamdy Ahmed Mhsb; Asmaa M Zahran; Mohamed Zein; Islam G Sayed

doi:10.1016/j.ijtb.2022.09.004

Frequency of rifampicin-resistant mycobacterium tuberculosis by GeneXpert MTB/RIF assay and its correlates among 2605 probable tuberculosis patients in upper Egypt

Indian J Tuberc. 2023 Jul;70(3):345-355. doi: 10.1016/j.ijtb.2022.09.004. Epub 2022 Sep 17.

Authors

Ebtisam S A Hassanin¹, Aliae Ar Mohamed Hussein², Shaimaa S Abdelrheem³, Ebtehal Dongol⁴, Ahmed Hamdy Ahmed Mhsb⁵, Asmaa M Zahran⁶, Mohamed Zein⁷, Islam G Sayed⁸

Affiliations

¹ Ministry of Health, Assiut, 71515, Egypt.
² Chest Department, Assiut University Hospitals, Assiut, 71515, Egypt. Electronic address: aliaehussein@gmail.com.
³ Department of Public Health and Community Medicine, Faculty of Medicine, Aswan University, Egypt and Armed Forces College of Medicine (AFCM), Cairo, Egypt.
⁴ South Valley University, Qena, Egypt.
⁵ Aswan University, Egypt.
⁶ Clinical Pathology Department, South Egypt Cancer Institute Assiut University, Egypt.
⁷ Faculty of Medicine, Assiut University, Egypt.
⁸ Aswan Faculty of Medicine, Aswan, Egypt.

PMID: 37562911
DOI: 10.1016/j.ijtb.2022.09.004

Abstract

Rationale: GeneXpert MTB/RIF (Mycobacterium tuberculosis/rifampicin) assay is a method for detecting rifampicin resistance (RR-MTB) in suspected samples in less than 2 hours with high sensitivity and specificity yield. This study aimed to use the GeneXpert MTB/RIF assay to determine the frequency of RR-MTB and to study the possible influencing correlates associated with positive results.

Subjects and methods: This is a retrospective cross-sectional study of patients who visited TB clinic in 5 years (2016-2021). According to the data sheet of the patients, all the collected specimens were divided into 2 parts one for diagnosis by Ziehl-Neelsen stain and the other part for GeneXpert analysis. GeneXpert was also used to look for evidence of RR.

Results: Out of the 2605 total samples screened, 718 (27.6%) tested positive for MTB on GeneXpert assay; of them 633 (88.4%) were sensitive to Rifampicin, 83 (11.6%) were resistant to Rifampicin and 2 cases were undetermined. Factors contributing to RR-MTB were: smoker/ex-smoker, with 2.5 times more risk (p = 0.013.0, p = 0.001); recurrence cases had a 4-fold increased risk (p < 0.001); patients with very low M. tuberculosis detected on the GeneXpert MTB/RIF test were 8 times more likely to have RR-TB (P = 0.004).

Conclusion: This study disclosed a high-rate MTB in Egyptian probable TB cases. Smoking, recurrence and cases with a very low M. tuberculosis burden noticed on the GeneXpert MTB/RIF test had augmented risk of RR-TB.

Keywords: Anti-TB drugs; Correlation; GeneXpert MTB/RIF test; Rifampicin resistance; Tuberculosis.

MeSH terms

Cross-Sectional Studies
Egypt / epidemiology
Humans
Mycobacterium tuberculosis* / genetics
Retrospective Studies
Rifampin / pharmacology
Rifampin / therapeutic use
Sensitivity and Specificity
Tuberculosis* / diagnosis
Tuberculosis, Multidrug-Resistant* / diagnosis
Tuberculosis, Multidrug-Resistant* / drug therapy
Tuberculosis, Multidrug-Resistant* / epidemiology

Substances

Rifampin