Rifampicin and isoniazid drug resistance among patients diagnosed with pulmonary tuberculosis in southwestern Uganda

Abstract

Multidrug-resistant tuberculosis (MDR-TB) has become a major threat to the control of tuberculosis globally. Uganda is among the countries with a relatively high prevalence of tuberculosis despite significant control efforts. In this study, the drug resistance of Mycobacterium tuberculosis to rifampicin (RIF) and isoniazid (INH) was investigated among patients diagnosed with pulmonary tuberculosis in Southwestern Uganda. A total of 283 sputum samples (266 from newly diagnosed and 17 from previously treated patients), collected between May 2018 and April 2019 at four different TB diagnostic centres, were assessed for RIF and INH resistance using high-resolution melt curve analysis. The overall prevalence of monoresistance to INH and RIF was 8.5% and 11% respectively, while the prevalence of MDR-TB was 6.7%. Bivariate analysis showed that patients aged 25 to 44 years were at a higher risk of developing MDR-TB (cOR 0.253). Furthermore, among the newly diagnosed patients, the prevalence of monoresistance to INH, RIF and MDR-TB was 8.6%, 10.2% and 6.4% respectively; while among the previously treated cases, these prevalence rates were 5.9%, 23.5% and 11.8%. These rates are higher than those reported previously indicating a rise in MTB drug resistance and may call for measures used to prevent a further rise in drug resistance. There is also a need to conduct frequent drug resistance surveys, to monitor and curtail the development and spread of drug-resistant TB.

Molecular characterisation of second-line drug resistance among drug resistant tuberculosis patients tested in Uganda: a two and a half-year’s review

“…The low proportions of INH mono-resistance at 9.8% (4.8–17.3) in this study may be attributed to a selection bias as a result of our selected study population. However, the higher proportions of RIF mono-resistance at 90.2% (82.7–95.2) are in agreement with two studies that raise awareness of increasing levels of this type of drug resistance among TB patients [ 24 , 25 ]. Malenfant and Brewer [ 24 ] recently reported that the availability of diagnostic assays that allow for quick detection of RIF resistance has increased awareness of patients with rifampicin mono-resistant TB (RR-TB), which was previously thought to be uncommon [ 24 ].…”

“…Mono-resistance to RIF was higher than INH monoresistance and is backed by recent studies that have raised more awareness on this phenomenon [ 24 , 25 ]. The low proportions of INH mono-resistance at 9.8% (4.8–17.3) in this study may be attributed to a selection bias as a result of our selected study population.…”

“…A study conducted in South-western Uganda by Micheni et al . [ 25 ] also reported that the overall prevalence of monoresistance to INH and RIF was 8.5% and 11% respectively, while the prevalence of MDR-TB was 6.7% [ 25 ].…”

Frequency of Mycobacterium tuberculosis in Pneumonia Patients and Prevalence of Virulence Genes

“…Patients who do not get adequate treatment may develop drug-resistant MTB (acquired resistance), which may then transmit to others (primary resistance) (Micheni et al 2021). Multidrugresistant tuberculosis (MDR-TB), which is defined as resistance to both isoniazid (INH) and rifampin (RIF for treating TB), is extremely concerning since second-line antimycobacterial medications need to be used over an extended period of time, are costly, and have a number of adverse effects (Zetola et al 2014).…”

Trends of Rifampicin Resistance in Patients with Pulmonary Tuberculosis: A Longitudinal Analysis Based on Drug Resistance Screening in Eastern China Between 2015 and 2019

“… 4 In other countries, such as Uganda, the rate of rifampicin resistance was 10.2% in newly treated patients and 23.5% in re-treated patients in 2018–2019. 7 In Ethiopia, the laboratory-detected rifampicin resistance rate was 6.3%. 8 As a representative province in eastern China, Zhejiang Province also has its own unique TB drug resistance rate.…”