The reliability of a rapid molecular detection method in determining the prevalence of rifampicin-resistant Mycobacterium tuberculosis in an urban district health facility in Malaysia
- Author:
Chuan Hun Ding
1
,
2
Author Information
1. Department of Medical Microbiology &
2. Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
- Collective Name:Anita Sulong; Asrul Abdul Wahab; Benjamin Gan; Sahlawati Mustakim; Husna Farhanah Ahmad
- Publication Type:Journal Article
- Keywords:
Mycobacterium tuberculosis;
pulmonary tuberculosis;
rifampicin;
Xpert MTB/RIF
- From:The Malaysian Journal of Pathology
2020;42(3):401-407
- CountryMalaysia
- Language:English
-
Abstract:
Introduction: Rifampicin is a key first-line antimycobacterial agent employed for the treatment of
pulmonary tuberculosis (PTB). This study sought to obtain prevalence data on rifampicin-resistant
Mycobacterium tuberculosis among smear-positive PTB patients in the Klang District of Malaysia.
Materials and Methods: A total of 103 patients from the Chest Clinic of Hospital Tengku Ampuan
Rahimah with sputum smears positive for acid-fast bacilli were included in this cross-sectional
study. All sputa were tested using Xpert MTB/RIF to confirm the presence of M. tuberculosis
complex and detect rifampicin resistance. Sputa were also sent to a respiratory medicine institute
for mycobacterial culture. Positive cultures were then submitted to a reference laboratory, where
isolates identified as M. tuberculosis complex underwent drug susceptibility testing (DST). Results:
A total of 58 (56.3%) patients were newly diagnosed and 45 (43.7%) patients were previously
treated. Xpert MTB/RIF was able to detect rifampicin resistance with a sensitivity and specificity
of 87.5% and 98.9%, respectively. Assuming that a single resistant result from Xpert MTB/RIF
or any DST method was sufficient to denote resistance, a total of 8/103 patients had rifampicinresistant M. tuberculosis. All eight patients were previously treated for PTB (p<0.05). The overall
prevalence of rifampicin resistance among smear-positive PTB patients was 7.8%, although it was
17.8% among the previously treated ones. Conclusion: The local prevalence of rifampicin-resistant
M. tuberculosis was particularly high among previously treated patients. Xpert MTB/RIF can be
employed in urban district health facilities not only to diagnose PTB in smear-positive patients, but
also to detect rifampicin resistance with good sensitivity and specificity.
- Full text:5.2020my01087.pdf
