Relatively low primary drug resistant tuberculosis in southwestern Ethiopia

Mycobacterium tuberculosis and rifampicin-resistant tuberculosis among tuberculosis presumptive patients in selected zones of Tigray, Northern Ethiopia, 2016-2019

Introduction

Tuberculosis (TB) is the second leading cause of mortality from an infectious disease worldwide. Multidrug-resistant tuberculosis (MDR-TB), where rifampicin-resistant TB is the biggest contributor, remains a global health threat. There is scant data on MTB and rifampicin resistance (RR-MTB) using Gene Xpert MTB/RIF assay in Ethiopia. This study aimed to determine the prevalence of MTB and RR-MTB among presumptive TB patients in Tigray, Northern Ethiopia.

Methods

A multi-center retrospective cross-sectional study was conducted from October 2019 to December 2019 among presumptive MTB patients from four hospitals in Tigray. Records of sputum sample results of presumptive MTB patients analyzed with Gene Xpert MTB/RIF assay from January 2016 to December 2019 were investigated. Data were extracted using a data-extraction tool from registration books and analyzed using SPSS ver.21. Statistically significant was set at p-value ≤0.05.

Results

From 17,329 presumptive adult MTB patients who had submitted sputum samples for TB diagnosis, 16,437 (94.9 %) had complete records and were included in the study. More than half (60.2 %) of them were males and ages ranged from 18 to 98 years. Majority of the participants: 15,047(91.5 %) were new cases and 11,750 (71.5 %) were with unknown HIV status. Prevalence of MTB was 9.7 % (95 % CI: 9.2-10.2 %) of these, rifampicin resistant-MTB was 8.7 % (95 % CI: 7.32-10.09 %). Age (being >29 years) [p < 0.001] and new cases [AOR = 0.46; 95%CI = 0.39, 0.53, p < 0.001] were associated with low TB infection. Age groups of 18-29 years were associated with higher RR-MTB [AOR = 3.08; 95 % CI = 1.07, 8.72, p = 0.036].

Conclusion

Nearly one-tenth of the presumptive tuberculosis patients tested positive for MTB; out of these, 8.7 % were RR-MTB. The high prevalence of TB and RR-MTB at a young age and previously treated cases calls for a concerted effort to improve and monitor TB treatment to reduce the problem.

Trend of pulmonary tuberculosis and rifampicin-resistance among tuberculosis presumptive patients in Central Tigray, Ethiopia; 2018 -2023: a six-year retrospective study

BACKGROUND

Tuberculosis (TB) is a major public health concern in the developing countries. Moreover, the emergence of multidrug-resistant tuberculosis is challenging. However, there are no organized data on the trends of pulmonary tuberculosis and rifampicin-resistant Mycobacterium tuberculosis in the study area.

METHODS

A retrospective cross-sectional study was conducted to fill the information gap in Central Tigray at St. Mary General Hospital between 2018 and 2023. Data were collected from the GeneXpert™ tuberculosis registration logbooks using standard checklists and analyzed using Statistical Package for Social Science version 22. After performing logistic regression, a p-value < 0.05 with a corresponding 95% confidence interval was considered statistically significant. Moreover, chi square test for trend was performed to assess the percentage of annual detection of pulmonary tuberculosis and rifampicin-resistant Mycobacterium tuberculosis during the study years.

RESULT

Presumptive pulmonary tuberculosis patients with complete data (n = 3696) were included in the study. The overall prevalence of pulmonary tuberculosis was 11.7%, of which 8.1% were resistant to rifampicin. The study revealed that the incidence of pulmonary tuberculosis has been increasing, mainly in the recent four years. Likewise, an increase in rifampicin-resistant Mycobacterium tuberculosis was observed with considerable fluctuations. Age, human immunodeficiency virus infection, and presumptive rifampicin-resistant Mycobacterium tuberculosis infection were significantly associated with the presence of pulmonary tuberculosis. Moreover, pulmonary tuberculosis was more prevalent among participants in the productive-age group.

CONCLUSION

Although there have been fluctuations, an increasing of pulmonary tuberculosis and rifampicin-resistant Mycobacterium tuberculosis has been observed in recent years. Hence, prevention and treatment strategies for tuberculosis should be strengthened to alleviate the burden of pulmonary tuberculosis and rifampicin-resistant Mycobacterium tuberculosis in the study area.

Determinants of multidrug-resistant tuberculosis among adults undergoing treatment for tuberculosis in Tigray Region, Ethiopia: a case-control study

BACKGROUND

Multidrug-resistant tuberculosis is a type of tuberculosis that is resistant to at least the first-line antituberculosis drugs namely, rifampicin and isoniazid. However, most of these studies were limited only to a single hospital. Therefore, this study aimed to identify the determinants of multidrug-resistant tuberculosis among adults undergoing treatment for tuberculosis in the Tigray region of Ethiopia.

METHODS

Hospital-based unmatched case-control study was conducted from 1 April 2019 to 30 June 2019. A simple random sampling method was used to select the required sample size. Variables at a p value less than 0.25 in bivariate analysis were entered into a multivariable analysis to identify the determinant factors of multidrug-resistant tuberculosis. Finally, the level of significance was declared at p<0.05.

RESULTS

Rural residence (adjusted OR (AOR) 2.54; 95% CI 1.34 to 4.83), HIV (AOR 4.5; 95% CI 1.4 to 14.2), relapse (AOR 3.86; 95% CI 1.98 to 7.5), return after lost follow-up (AOR 6.29; 95% CI 1.64 to 24.2), treatment failure (AOR 5.87; 95% CI 1.39 to 24.8) were among the determinants of multidrug-resistant tuberculosis.

CONCLUSION

Rural residence, HIV, relapses, return after lost follow-up and treatment failure were the identified determinant factors of multidrug-resistance tuberculosis.

Pulmonary tuberculosis and multidrug-resistant Mycobacterium tuberculosis in northwestern Ethiopia: a hospital-based cross-sectional study among presumptive pulmonary tuberculosis patients

Introduction

Border areas are important sites for disseminating Mycobacterium tuberculosis among individuals living in such areas. This study examined patients with suspected pulmonary tuberculosis (PTB) visiting the Abrihajira and Metema hospitals in northwest Ethiopia to investigate the prevalence of rifampicin-resistant Mycobacterium tuberculosis (RR-MTB), multidrug-resistant Mycobacterium tuberculosis (MDR-MTB), and risk factors related to Mycobacterium tuberculosis infection.

Methods

A hospital-based cross-sectional study was conducted from February to August 2021 among 314 PTB presumptive patients. Xpert MTB/RIF and line probe assays (LPA) were used to process sputum samples. Data were imported into the Epi-Data 3.1 program and exported to Statistical Package for the Social Sciences (SPSS) version 20.0 (SPSS, Chicago, IL, United States) to conduct the analysis. A logistic regression analysis was used to investigate the relationship between the dependent and independent variables. A value of p of <0.05 denoted statistical significance.

Results

Of the total (314) PTB presumptive patients who participated in this study, 178 (56.69%) were men, and 165 (52.5%) were from 25 to 50 years of age with a median age of 35.00 (inter-quartile: 25-45 years). Among all patients, 12.7% had PTB by Gene Xpert and 7/314 (2.23%) were resistant to rifampicin. Among patients enrolled, 4/314 (1.27%) had MDR-MTB (resistant to RIF and INH) by LPA. Regarding the risk factors assessed, primary level of education, sputum production, night sweating, respiratory disorder, contact history of TB, history of MDR-MTB infection, history of alcohol use, and cigarette smoking showed statistical significance with the prevalence of PTB (p ≤ 0.05).

Discussion

This study observed a high prevalence of PTB, RR-MTB, and MDR-MTB compared with many other previous studies conducted in Ethiopia. Among the assessed risk factors that could be associated with the prevalence of PTB, eight were statistically significant. This prevalence, resistance, and statistically significant variables are the evidence to which more emphasis should be given to the country's border areas.

Multi-drug-resistant tuberculosis and its associated factors among pulmonary tuberculosis patients linked to first-line anti-tuberculosis drugs in north-west Ethiopia

Introduction. Multi-drug-resistant tuberculosis (MDR-TB) is an emerging global challenge. Ethiopia is one of the 20 top countries with the highest estimated numbers of incidents of MDR-TB. Recently, the World Health Organization warned that drug-resistant TB is escalating and called for concerted action to reduce the spread of drug resistance.Hypothesis. The current study investigated MDR-TB in patients receiving first-line anti-TB drug treatment and associated factors.Aim. The study aimed to determine the prevalence of MDR-TB and its associated factors among smear-positive pulmonary TB patients receiving first-line anti-TB drug treatment.Methodology. An institution-based cross-sectional study was employed. All data were collected from laboratory result log books and information via a questionnaire. Samples from 205 smear-positive pulmonary TB patients were selected among first-line drug treatment by a systematic sampling method. Specimens were transported to Felege Hiwot referral hospital laboratory for GeneXpert testing. Factors associated with an outcome variable in binary multi-variable logistic regression analysis at P<0.05 were considered statistically significant variables. An ethical approval letter was taken to the respective health facility and written consent was obtained from each participant.Results. The overall prevalence of MDR-TB was 9.3 % (95 % CI, 5.4 13.7 %). Sign and symptom experience of anti-TB drug side effects [adjusted odds ratio (AOR)=0.18, 95 % CI=0.03-0.99, P=0.049] and co-morbidity (AOR=0.03, 95 % CI=0.01-0.55, P=0.02) were statistically associated with the development of MDR-TB infectionConclusion. The prevalence of MDR-TB was high (9.3 %) and contributed highly to new cases (8.3 %). Factors associated with MDR-TB were previous treatment, co-morbidity and laboratory diagnosis method prior to TB treatment. Therefore, this finding aims to maximize early detection and treatment, strengthening TB infection control, and proper implementation of directly observed therapy short course recommendations to reduce the burden of MDR-TB.

Global prevalence of drug-resistant tuberculosis: a systematic review and meta-analysis

BACKGROUND

Tuberculosis is a bacterial infectious disease, which affects different parts of a human body, mainly lungs and can lead to the patient's death. The aim of this study is to investigate the global prevalence of drug-resistant tuberculosis using a systematic review and meta-analysis.

METHODS

In this study, the PubMed, Scopus, Web of Science, Embase, ScienceDirect and Google Scholar repositories were systematically searched to find studies reporting the global prevalence of drug-resistant tuberculosis. The search did not entail a lower time limit, and articles published up until August 2022 were considered. Random effects model was used to perform the analysis. The heterogeneity of the studies was examined with the I² test. Data analysis was conducted within the Comprehensive Meta-Analysis software.

RESULTS

In the review of 148 studies with a sample size of 318,430 people, the I² index showed high heterogeneity (I² = 99.6), and accordingly random effects method was used to analyze the results. Publication bias was also examined using the Begg and Mazumdar correlation test which indicated the existence of publication bias in the studies (P = 0.008). According to our meta-analysis, the global pooled prevalence of multi-drug resistant TB is 11.6% (95% CI: 9.1-14.5%).

CONCLUSIONS

The global prevalence of drug-resistant tuberculosis was found to be very high, thus health authorities should consider ways to control and manage the disease to prevent a wider spread of tuberculosis and potentially subsequent deaths.

Gender and Drug-Resistant Tuberculosis in Nigeria

We conducted a retrospective study of 2555 DR-TB patients admitted to treatment between 2010 and 2016 in six geopolitical zones in Nigeria. We characterized the gender distribution of DR-TB cases and the association between demographics and clinical data, such as age, treatment category, number of previous TB treatment cycles, and geopolitical zone, with gender. The independent effects of being a male or female DR-TB patient were determined using bivariate and multivariate analyzes with statistical significance of p < 0.05 and a 95% confidence interval. Records from a total of 2555 DR-TB patients were examined for the study. A majority were male (66.9%), largest age-group was 30-39 years old (35.8%), most had MDR-TB (61.4%), were HIV-negative (76.6%), and previously treated for TB (77.1%). The southwest treatment zone had the highest proportion of DR-TB patients (36.9%), and most DR-TB diagnoses occurred in 2016 (36.9%). On bivariate analysis, age, HIV status, treatment zone, and clinical patient group in DR-TB were significantly associated with male gender. On multivariate analysis, males aged 20-29 years (AOR: 0.19, 95% CI: 0.33-0.59, p = 0.001) and HIV-positive males (AOR: 0.44, 95% CI: 0.33-0.59, p = 0.001) had lower likelihood of MDR-TB as males in the south-south treatment zone (AOR: 1.88, 95% CI: 1.23-2.85, p = 0.03), and being male and aged ≥60 years (AOR: 2.19, 95% CI: 1.05-4.54, p = 0.036) increased the probability of DR-TB. The older male population from south-southern Nigeria and women of childbearing age had lower incidence of DR-TB than men of the same age. Tailored interventions to reduce HIV and DR-TB prevalence in the general population, particularly among women of childbearing potential, and treatment support for young and older men are relevant strategies to reduce DR-TB in Nigeria.

Drug sensitivity of clinical isolates of Mycobacterium tuberculosis and its association with bacterial genotype in the Somali region, Eastern Ethiopia

Background

Drug resistance is becoming a major bottleneck for tuberculosis (TB) control programs in countries with high TB burdens. Although several studies were conducted on the drug sensitivity of Mycobacterium tuberculosis (M. tuberculosis) in central Ethiopia, there is a lack of data on the drug sensitivity of M. tuberculosis in the peripheral regions of the country including in the Somali region. Therefore, the objective of this study was to evaluate the drug sensitivity of M. tuberculosis and its association with bacterial genotype and evaluate the performance of Xpert MTB/RIF (Xpert) in detecting resistance to rifampicin (RIF).

Methods

A total of 302 M. tuberculosis were tested using the BD BACTEC-Mycobacteria Growth Indicator Tube 960 (MGIT 960) system for their drug sensitivity to the first-line anti-TB drugs. Besides, the drug sensitivity of 10 multidrug-resistant (MDR) M. tuberculosis isolates was evaluated for the second-line anti-TB drugs. Additionally, 177 of the 302 isolates were tested for genotypic drug resistance using Xpert. Chi-square and Fisher's exact tests were used for the evaluation of the association between variables and drug sensitivity.

Results

The overall prevalence of resistance to at least one drug was 11.6% (95% CI: 7.9-15.2%), while the prevalence of MDR was 3.3% (95% CI: 1.3-5.3%). Two of the 10 MDR isolates were resistant to capreomycin. The spoligotype Shared International Type (SIT) 149 was significantly associated with either monoresistance or MDR (p < 0.05). Of the 177 isolates tested by Xpert, 6.2% (11/177) were RIF-resistant. Discordant between Xpert and MGIT 960 was observed in one isolate and linked with probe-binding delay (ΔCT max = 5.8). The sensitivity and specificity of the Xpert assay were 100 and 99.4%, respectively, while its positive and negative predictive values were 90.9 and 100%, respectively.

Conclusion

The magnitude of MDR M. tuberculosis in the Somali region of Ethiopia was higher than the national prevalence of MDR-TB warranting the strengthening of the TB control program in the Somali region. Besides, drug resistance was associated with SIT 149 spoligotype (genotype). The Xpert assay was observed to have high sensitivity and specificity in detecting RIF-resistant M. tuberculosis, which is encouraging for its application widely.

Detection of Mycobacterium tuberculosis and rifampicin resistance by Xpert® MTB/RIF assay among presumptive tuberculosis cases at Jimma University Medical Center, Southwest Ethiopia

Background

Rapid diagnosis of tuberculosis (TB) and detection of drug resistance are very important for timely and appropriate management of patients. Xpert MTB/RIF assay is approved for use in TB and rifampicin-resistance diagnosis. However, data are limited on the impact of Xpert MTB/RIF assay under routine clinical settings with a heterogeneous group of patients and sample types in Ethiopia.

Methods

A retrospective study was carried out in 2220 presumptive TB cases at Jimma University Medical Center. Data were gathered from the registration logbook using formatted data extraction tools and double entered to epidata version 3.1 and further transported to SPSS version 20 for analysis. Associations were determined using the Chi-square test and P-value <0.05 was considered statistically significant.

Results

Of 2220 cases enrolled, 1665 (75%) were adults and the remaining 555 (25%) were children aged less than 14 years. The majority, 1964 (88.46%), had pulmonary manifestation and 256 (11.54%) had extrapulmonary involvements. The overall, frequency of Mycobacterium tuberculosis (MTB) was 9.3% (206/2220), among this 10.27% (171/1665) and 6.3% (35/555) were adults and children, respectively. M. tuberculosis was detected from 171 (8.75%) of pulmonary patients and 35 (13.28%) of extrapulmonary manifested patients. Out of 206 M. tuberculosis positive cases, 7(3.4%) were rifampicin-resistant: four from pulmonary tuberculosis (PTB) patients and three from EPTB patients. In the Chi-square test, the age group of 15–24 years, previous history of TB, pus/lymph node sample, and being HIV positive were significantly associated with TB positivity by Xpert MTB/RIF (P-value <0.001).

Conclusion

These data suggest that the overall frequency of M. tuberculosis and rifampicin resistance was found to be relatively low compared to the previous reports in Ethiopia. Nevertheless, better diagnostic tools and approaches are still vital to halt the burden of TB and drug-resistant TB in the country.

The Magnitude of MTB and Rifampicin Resistance MTB Using Xpert-MTB/RIF Assay Among Tuberculosis Suspected Patients in Gedeo Zone, Southern Ethiopia

Background

Tuberculosis (TB) remains a major global health problem causing death among millions of people each year. The new barrier that challenges the control of tuberculosis is the emerging and the increasing number of drug-resistant TB that becomes a world concern. This study aimed to determine the magnitude of rifampicin-resistant Mycobacterium tuberculosis (RR-MTB) among presumptive TB patients attending Dilla University Referral Hospital, Gedeo Zone, Ethiopia.

Methods

A retrospective cross-sectional study was conducted at Dilla University Referral Hospital from January 2014 to December 2020. Sputum results were done using Xpert MTB/RIF assay and other necessary data were collected from the registration logbooks using a standardized data extraction format and analyzed using SPSS version 23 statistical software.

Results

A total of 17,745 presumptive TB patients were included, of which 62.2% were males. The overall prevalence of Mycobacterium tuberculosis (MTB) was 11.8%, of which 5.1% were confirmed to have RR-MTB. Extra-pulmonary TB was reported in 1.5% of the study participants. The highest prevalence of MTB and RR-MTB was recorded in 2017 with a prevalence of 20.1% and 8.5%, respectively. All age groups were significantly associated with a higher prevalence of MTB (p < 0.036). TB patients with a history of previous treatment and HIV positive were significantly associated with MTB (P < 0.021), while RR-MTB was only significantly associated with patients with a history of previous treatment (P < 0.018).

Conclusion

A high magnitude of MTB and RR-MTB was reported among TB patients with HIV and a history of previous treatment. Therefore, coordinated efforts should be applied to the improvement of treatment adherence of known TB cases, and appropriate control and prevention methods to reduce the emergence and increase of MTB and RR-MTB cases.

Molecular Epidemiology of Mycobacterium tuberculosis strains isolated from pulmonary tuberculosis patients in south Ethiopia

Introduction:

Understanding the epidemiology of tuberculosis is limited by lack of genotyping data. We sought to characterize the drug susceptibility testing patterns and genetic diversity of M. tuberculosis isolates in southern Ethiopia.

Methodology:

A cross-sectional study was conducted among newly diagnosed sputum smear positive patients with tuberculosis visiting nine health facilities in southern Ethiopia from June 2015 to May 2016. Three consecutive sputum samples (spot-morning-spot) per patient were examined using acid-fast bacilli smear microscopy with all smear positive specimens having acid-fast bacilli cultures performed. M. tuberculosis isolates had drug susceptibility testing performed using indirect proportion method and were genotyped with RD9 deletion analysis and spoligotyping. Mapping of strain was made using geographic information system.

Results:

Among 250 newly diagnosed patients with tuberculosis, 4% were HIV co-infected. All 230 isolates tested were M. tuberculosis strains belonging to three lineages: Euro-American, 187 (81%), East-African-Indian, 31 (14%), and Lineage 7 (Ethiopian lineage), 8 (4%); categorized into 63 different spoligotype patterns, of which 85% fell into 28 clusters. M. tuberculosis strains were clustered by geographic localities. The dominant spoligotypes were SIT149 (21%) and SIT53 (19%). Drug susceptibility testing found that 14% of isolates tested were resistant to ≥ 1 first line anti- tuberculosis drugs and 11% to INH. SIT 149 was dominant among drug resistant isolates.

Conclusions:

The study revealed several clusters and drug resistant strains of M. tuberculosis in the study area, suggesting recent transmission including of drug resistant tuberculosis. Wider monitoring of drug susceptibility testing and geospatial analysis of transmission trends is required to control tuberculosis in southern Ethiopia.

Differential yield of universal versus selective drug susceptibility testing of patients with tuberculosis in high-burden countries: a systematic review and meta-analysis

Introduction

Although universal drug susceptibility testing (DST) is a component of the End-TB Strategy, over 70% of drug-resistant tuberculosis (DR-TB) cases globally remain undetected. This detection gap reflects difficulties in DST scale-up and substantial heterogeneity in policies and implemented practices. We conducted a systematic review and meta-analysis to assess whether implementation of universal DST yields increased DR-TB detection compared with only selectively testing high-risk groups.

Methods

PubMed, Embase, Global Health, Cochrane Library and Web of Science Core Collection were searched for publications reporting on the differential yield of universal versus selective DST implementation on the proportion of DR-TB, from January 2007 to June 2019. Random-effects meta-analyses were used to calculate respective pooled proportions of DR-TB cases detected; Higgins test and prediction intervals were used to assess between-study heterogeneity. We adapted an existing risk-of-bias assessment tool for prevalence studies.

Results

Of 18 736 unique citations, 101 studies were included in the qualitative synthesis. All studies used WHO-endorsed DST methods, and most (87.1%) involved both high-risk groups and the general population. We found only cross-sectional, observational, non-randomised studies that compared universal with selective DST strategies. Only four studies directly compared the testing approaches in the same study population, with the proportion of DR-TB cases detected ranging from 2.2% (95% CI: 1.4% to 3.2%) to 12.8% (95% CI: 11.4% to 14.3%) with selective testing, versus 4.4% (95% CI: 3.3% to 5.8%) to 9.8% (95% CI: 8.9% to 10.7%) with universal testing. Broad population studies were very heterogeneous. The vast majority (88/101; 87.1%) reported on the results of universal testing. However, while 37 (36.6%)/101 included all presumptive TB cases, an equal number of studies applied sputum-smear as a preselection criterion. A meaningful meta-analysis was not possible.

Conclusion

Given the absence of randomised studies and the paucity of studies comparing strategies head to head, and selection bias in many studies that applied universal testing, our findings have limited generalisability. The lack of evidence reinforces the need for better data to inform policies.

Prevalence of Mycobacterium tuberculosis (Rifampicin-Resistant MTB) and Associated Risk Actors Among Pulmonary Presumptive TB Patients in Eastern Amhara, Ethiopia: 2015-2019

INTRODUCTION

Tuberculosis (TB) is a major health problem, mainly in resource-limited settings. The aim of this study was to determine the prevalence of TB and rifampicin-resistant Mycobacterium tuberculosis (RR-MTB) among presumptive tuberculosis patients using Xpert MTB/RIF assay in Eastern Amhara, Ethiopia.

METHODS

A retrospective cross-sectional study was conducted among presumptive TB patients from three governmental hospitals in Amhara Regional State. Records of sputum sample results using Xpert MTB/RIF assay from January 2015 to December 2019 were investigated from registration books and analyzed using SPSS v.21.

RESULTS

Of the total of 26,656 (24,116 adults and 2540 children) TB presumptive patients included in the study, more than half, 14,624 (54.9%), were males and the median age was 36.87 (interquartile: 25.46-50.85 years). The majority of participants were new cases, 20,273 (76.1%), and with unknown HIV status, 18,981 (71.2%), respectively. MTB prevalence was 11% (95% CI: 9.34-12.08%) in all age groups, and 7.6% (95% CI 6.52-9.04%) among children. Of the MTB confirmed cases, prevalence of RR-MTB was 245 (8.3%) in adults and 14 (7.2%) in children. MTB infection was higher in the age groups of 18-35 years [adjusted odds ratio (AOR) = 2.17; 95% CI: 1.86-2.54, p < 0.001], 36-53 years (AOR = 1.31; 95% CI 1.11-1.54, p < 0.001), those who were relapse cases (AOR = 1.97; 95% CI 1.69-2.27, p < 0.0010), and failure cases (AOR = 4.67; 95% CI 3.36-6.50, p < 0.001). However, the age groups of 54-71 years (AOR = 0.79; 95% CI 0.65-0.95, p = 0.01) and over 71 years (AOR = 0.48; 95% CI 0.35-0.68, p < 0.001) were associated with lower MTB infection. Resistance to rifampicin was higher in the relapsed (AOR = 2.10; 95% CI 1.40-3.03, p < 0.001) and failure cases (AOR = 3.50; 95% CI 1.9-6.61, p < 001).

CONCLUSION

Prevalence of MTB and RR-MTB low. TB infection was higher in adult age groups and those who had previous TB treatment history. Similarly, resistance to rifampicin was higher among the relapsed and failure patients. Appropriate measurements in monitoring of TB treatment could reduce TB and RR-MTB in the study area.

Frequency of MTB and rifampicin resistance MTB using Xpert-MTB/RIF assay among adult presumptive tuberculosis patients in Tigray, Northern Ethiopia: A cross sectional study

BACKGROUND

Multidrug-resistant tuberculosis (MDR-TB) continues to be a global health problem. Data on rifampicin resistance MTB using Xpert- MTB/RIF assay in Ethiopia, particularly in the study area is limited. The aim of this study was to determine the frequency of MTB and rifampicin resistant-MTB among presumptive tuberculosis patients in Tigray, Northern Ethiopia.

METHODS

A multicenter retrospective study was conducted among presumptive TB patients from five governmental hospitals and one comprehensive specialized teaching hospital in Tigray regional state. Records of sputum sample results of presumptive MTB patients with Xpert-MTB/RIF assay from January 2016 to December 2019 were investigated. Data extraction tool was used to collect data from registration books and analyzed using SPSS ver.21 statistical software. Statistical significance was set at p-value ≤ 0.05.

RESULTS

Of the 30,935 presumptive adult TB patients who have provided specimens for TB diagnosis from January 2016 to December 2019, 30,300 (98%) had complete data and were included in this study. More than half, 17,471 (57.7%) were males, and the age of the patients ranged from 18-112 years, with a median age of 40.65 (interquartile 29.4-56.5 years). Majority, 28,996 (95.7%) of the participants were treatment naïve, and 23,965 (79.1%) were with unknown HIV status. The overall frequency of MTB was 2,387 (7.9% (95% CI: 7.6-8.2%); of these, 215 (9% (95% CI: 7.9-10.2%) were rifampicin resistant-MTB. Age (18-29 years), HIV positive and previous TB treatment history were significantly associated with high MTB (p < 0.001), whereas gender (being female) was associated with low MTB (p < 0.001). Likewise, rifampicin resistant-MTB was more prevalent among relapse (p < 0.001) and failure cases (p = 0.025); while age group 30-39 years was significantly associated with lower frequency of rifampicin resistant-MTB (p = 0.008).

CONCLUSION

Frequency of MTB among tuberculosis presumptive patients was low; however, the problem of rifampicin resistant-MTB among the tuberculosis confirmed patients was high. The high frequency of MTB and RR-MTB among previously treated and HIV positive patients highlights the need for more efforts in TB treatment and monitoring program in the study area.

Spoligotyping and drug sensitivity of Mycobacterium tuberculosis isolated from pulmonary tuberculosis patients in the Arsi Zone of southeastern Ethiopia

Tuberculosis (TB) is one of the leading causes of morbidity and mortality in different zones of Ethiopia. This study was undertaken to identify the strains of Mycobacterium tuberculosis and evaluate their drug sensitivity profiles in the Arsi Zone. A total of 111 isolates of M. tuberculosis from individuals with pulmonary TB were included and speciation and strain identification were performed using Region of difference 9 and spoligotyping, respectively. The drug sensitivity patterns were assessed using Bactec MGIT 960 SIRE and GenoType MTBDRplus line probe assays. Of 111 isolates, 83% were interpretable and 56 different spoligotype patterns were identified. From these, 22 patterns were shared types while the remaining 34 were orphans. The predominant shared types were spoligotype international type (SIT) 149 and SIT53, comprising 12 and 11 isolates, respectively. Euro-American lineage was the dominant lineage followed by East-African-Indian. Phenotypically, 17.2% of tested isolates were resistant to any first-line drugs and 3.1% were multidrug-resistant. Higher (6.2%) mono-resistance was observed to streptomycin, and no resistance was observed to rifampicin or ethambutol. Genotypically, five (5.4%) isolates were resistant to isoniazid and mutated at codon S315T1 of katG. In contrast, only 1.1% of the isolates were resistant to rifampicin and were mutated at codon S531L of rpoB gene. In this study, a high proportion of orphan strains were isolated, which could suggest the presence of new strains and a high percentage of mono-resistance, warranting the need to strengthen control efforts.

Bacterial Infections and Their Antibiotic Resistance Pattern in Ethiopia: A Systematic Review

Background

Antibiotic resistance is a global challenge in the public health sector and also a major challenge in Ethiopia. It is truly difficult to report bacterial antibiotic resistance pattern in Ethiopia due to the absence of a review which is done comprehensively. The aim of this systematic review was to provide an overview of the works of literature on the antibiotic resistance pattern of the specific bacterial isolates that can be obtained from different clinical samples in the context of Ethiopia.

Materials and Methods

A web-based search using PubMed, Google Scholar, Hinari, Sci Hub, Scopus and the Directory of Open Access Journals was conducted from April to May 2018 for published studies without restriction in the year of publication. Works of literature potentially relevant to the study were identified by Boolean search technique using various keywords: Bacterial infection, antimicrobial resistance, antibiotic resistance, drug resistance, drug susceptibility, anti-bacterial resistance, Ethiopia. Study that perform susceptibility test from animal or healthy source using <10 isolates and methods other than prospective cross-sectional were excluded.

Results

The database search delivered a total of 3459 studies. After amendment for duplicates and inclusion and exclusion criteria, 39 articles were found suitable for the systematic review. All studies were prospective cross-sectional in nature. The review encompasses 12 gram-positive and 15 gram-negative bacteria with their resistance pattern for around 12 antibiotics. It covers most of the regions which are found in Ethiopia. The resistance pattern of the isolates ranged from 0% up to 100%. The overall resistance of M. tuberculosis for antituberculosis drugs ranges from 0% up to 32.6%. The percentage of resistance increases among previously treated tuberculosis cases. Neisseria gonorrhea, S. typhimurium, S. Virchow, Group A Streptococci (GAS), and Group B Streptococci (GBS) were highly susceptible for most of the tested antibiotics. Methicillin-Resistant Staphylococcus aureus was highly resistant to most of the antibiotics with a slightly increased susceptibility to gentamycin.

Conclusions

Total bacterial isolates obtained from a different source of sample and geographic areas were 28, including M. tuberculosis. Majority of the bacterial isolates were resistant to commonly used antibiotics. A continuous monitoring and studies on the multidrug-resistant bacterial isolates are important measures.

Molecular detection of Mycobacterium tuberculosis sensitivity to rifampicin and isoniazid in South Gondar Zone, northwest Ethiopia

Background

Drug resistant tuberculosis (TB) has become a persistent health threat in Ethiopia. In this respect, baseline data are scarce in many parts of high TB burden regions including the different zones of Ethiopia.

Methods

A total of 111 culture positive M. tuberculosis isolates were recovered from TB patients and identified using region of difference (RD) 9 based polymerase chain reaction (PCR) and spoligotyping. Thereafter, their drug sensitivities to Rifampicin (RIF) and Isoniazid (INH) were evaluated using GenoType MTBDRplus assay.

Results

The result showed that 18.0% (20/111) of the isolates were resistant to either RIF or INH. Furthermore, 16.7 and 23.8% of the isolates from new and retreatment cases were resistant to any of the two anti-TB drugs, respectively. Multi-drug resistant (MDR) TB was detected on 1.8% (2/111) of all cases. Significantly higher frequencies of any drug resistance were observed among Euro-American (EA) major lineage (χ²: 9.67; p = 0.046).

Conclusion

Considerably high proportion of drug resistant M. tuberculosis strains was detected which could suggest a need for an increased effort to strengthen TB control program in the study area.

Spoligotype-based population structure of Mycobacterium tuberculosis in the Jimma Zone, southwest Ethiopia

Background

To understand the population dynamics and propose more effective preventive strategies, defining the population structure of the circulating Mycobacterium tuberculosis strains is important.

Methods

A total of 177 M. tuberculosis complex isolates from pulmonary tuberculosis (TB) cases in southwest Ethiopia were genotyped by spoligotyping. Of the strains included in this study, 126 were pan‐susceptible strains while the remaining 51 isolates were resistant to one or more first‐line anti‐TB drugs. The genotyping results were compared to the international spoligotyping (SITVIT) database of the Pasteur Institute of Guadeloupe and the newly revised publicly available international multi‐marker database (SITVITWEB/SPOLDB4). An online tool Run TB‐Lineage was also used to predict the major lineages using a conformal Bayesian network analysis.

Results

The spoligotyping of the 177 isolates resulted in 69 different spoligotype patterns of which 127 (71.8%) were clustered into 19 spoligoclusters (with clustering rate of 61.02%). Each cluster contains 2–29 isolates. Of the isolates with corresponding SIT in SITVIT/SDB4, the predominant strains identified were SIT 37 of the T3 subfamily with 29 isolates followed by SIT 53 of the T1 subfamily with 20 isolates. SIT 777 of the H4 subfamily and SIT 25 of the CAS1_DELHI subfamily each consisting of six isolates were identified. Eighty spoligotype patterns were orphan as they were not recorded in the SITVIT2/SPDB4 database. Further classification of the isolates on the basis of major lineages showed that 82.5% and 14.1% of the isolates belonged to Euro‐American and East African Indian lineages, respectively, while 2.8% of the isolates belonged to Mycobacterium africanum and 0.6% to Indo‐Oceanic.

Conclusion

The ill‐defined T and H clades were predominant around Jimma. The substantial number of orphans recorded in the study area warrants for additional studies with genotyping methods with better resolution and covering whole areas of southwest Ethiopia.

The present study has shown the dominance of ill‐defined T and H clades in the study area. Moreover, a substantial number of isolates were Orphan warranting for additional studies covering the whole geographic area of the southwest Ethiopia and genotypic methods with better resolution.

Epidemiology of multidrug-resistant tuberculosis (MDR-TB) in Ethiopia: a systematic review and meta-analysis of the prevalence, determinants and treatment outcome

INTRODUCTION

The emergence of MDR-TB remained a major public health threat particularly in developing countries. With increased prevalence and complexity of treatment, the burden of MDR-TB challenged the country. It is of an important; the epidemiology of drug resistant TB is not well understood. There are few studies conducted to assess the prevalence, determinants and treatment outcome of MDR-TB with inconclusive finding. Therefore, we aimed to conduct a systematic review and meta-analysis on Epidemiology of MDR-TB in Ethiopia, So that policy makers and other stalk holders could have pooled evidence on the problem to make a decision.

METHODS

The review was conducted through a systematic literature search of articles published between 1997 and 2017. Five bibliographic databases and libraries: PubMed/Medline, Global Health Database, Embase, the Cochrane Library, and African Index Medicus were used. After cleaning and sorting, analysis was performed using STATA version 11. The pooled rate of MDR-TB prevalence, determinants and treatment outcome was estimated with a random-effects model. Heterogeneity was assessed by the I2 and publication bias through funnel plot.

RESULTS

The 34 studies that were retained for final analysis enrolled a total of 7461 TB or MDR-TB patients. We found that 2.18% (95% CI 1.44-2.92%) of newly diagnosed and 21.07% (95% CI 11.47-30.67%) of previously treated patients have MDR-TB with overall prevalence of 7.24% (95% CI 6.11-8.37). History of previous treatment is the major determinant (pooled OR = 4.78 (95% CI 3.16-6.39)), while contact history and adherence also contributed. In this review the pooled death computed among 5 articles showed that 12.25% (95% CI 9.39-15.11%) of MDR-TB patients were died in the course of treatment. Complication, drug side effects and HIV infection were the main determinants for the death.

CONCLUSION AND RECOMMENDATION

The prevalence is by far higher than the previous reports. It is mainly associated with history of previous treatment along with contact history. However, the treatment outcomes are comparable with previous studies, yet it is a concern. Comorbidities, drug side effects and HIV sero-positivity were the determinants. Thus, proper treatment of drug susceptible TB and early detection and treatment of MDR-TB before complication develops along with prevention of drug side effect and contacts with MDR-TB cases are very important.

Prevalence of Multidrug-Resistant Tuberculosis and Associated Factors in Ethiopia: A Systematic Review

Background

Multidrug-resistant tuberculosis (MDR-TB) has continued to be a challenge for tuberculosis (TB) control globally. Ethiopia is one of the countries with high MDR-TB burden.

Objective

The main purpose of this study was to determine the prevalence of MDR-TB and associated factors in Ethiopia.

Methods

A systematic review of the literatures on prevalence of MDR-TB and associated factors was conducted in the country.

Results

In our electronic search, 546 citations were depicted. Among the total 546 citations described, a total of 22 articles met eligibility criteria and were included in the review article. According to our review, the prevalence of MDR-TB ranged from 0 to 46.3%. The average mean rate of MDR-TB in Ethiopia was found to be 12.6 ± 15.9%. The overall prevalence of MDR-TB in all TB cases was estimated to be 1.4%. From a total of 3849 patients studied, 527 had MDR-TB. Previous exposure to antituberculosis treatment was the most commonly identified risk factor of MDR-TB in Ethiopia.

Conclusion

Despite relative decline in incidence of MDR-TB, the distribution and prevalence of MDR-TB continued to be a serious challenge for TB control in Ethiopia. Previous exposure to antituberculosis treatment was also the most common risk factor for MDR-TB. Therefore, strong TB and MDR-TB treatment along with tight introduction of follow-up strategies should be applied for better TB control.

Risk factors for the occurrence of multidrug-resistant tuberculosis among patients undergoing multidrug-resistant tuberculosis treatment in East Shoa, Ethiopia

BACKGROUND

Multidrug-resistant tuberculosis (MDR-TB) is resistant to the two main first-line anti-tuberculosis drugs: rifampicin and isoniazid. It is a major threat to public health worldwide. The objective of this study was to assess the potential risk factors for multidrug-resistant tuberculosis among patients undergoing MDR-TB treatment at two community hospitals in Ethiopia.

METHODS

A case-control study design was conducted from February 1, 2016, to April 29, 2016. TB-positive patients with MDR-TB and non-MDR-TB were considered as cases and controls, respectively. A total of 219 study participants were included in the study. An interviewer-administered structured questionnaire was used to collect primary data from the patients, and a checklist was used to collect data from the clinical records. Bivariate and multivariate logistic regression analyses were used to assess the potential risk factors for the occurrence of MDR-TB.

RESULTS

The odds of developing MDR-TB were higher in patients previously treated with anti-TB drugs (odds ratio [OR] = 6.1, 95%CI: 2.92-12.62, P < 0.001), those with a history of contact with known TB patients (OR = 2.1, 95%CI: 1.04-4.43, P < 0.001), those living in a rural setting (OR = 5.6, 95%CI: 2.14-14.46, P = 0.001), those with a history of alcohol consumption (OR = 4.3, 95%CI: 2.29-10.49, P < 0.001) and those without a job (OR = 2.4, 95%CI: 1.06-5.42, P = 0.001).

CONCLUSIONS

The study revealed that contact with known TB patients, previous TB treatment, residence area, lack of a job, and alcohol consumption were potential risk factors for the occurrence of MDR-TB. Enhancing public health education, intensifying directly observed therapy programmes for all TB patients and designing control strategies are recommended.

Molecular epidemiology and drug sensitivity pattern of Mycobacterium tuberculosis strains isolated from pulmonary tuberculosis patients in and around Ambo Town, Central Ethiopia

INTRODUCTION

Tuberculosis (TB) is caused by M. tuberculosis complex and remains a major global public health problem. The epidemic remains a threat to sub-Saharan Africa, including Ethiopia, with further emergence of drug resistant TB. We investigated the drug sensitivity pattern and molecular epidemiology of mycobacterial strains isolated from pulmonary TB patients in and around Ambo town in Oromia Region, Central Ethiopia.

METHODS

A cross-sectional study was conducted involving 105 consecutive new smear positive pulmonary TB patients diagnosed at Ambo Hospital and surrounding Health Centers between May 2014 and March 2015 upon informed consent. Sputum samples were cultured on Löwenstein-Jensen (LJ) media using standard techniques to isolate mycobacteria. Region of difference 9 (RD9)-based polymerase chain reaction (PCR) and spoligotyping was employed for the identification of the isolates at species and strain levels. The spoligotype patterns were entered into the SITVIT database to determine Octal and SIT (Spoligotyping International Typing) numbers for each strain. The sensitivity of the isolates to isoniazid (INH), rifampicin (RIF), ethambutol (ETB) and streptomycin (STM) was evaluated on LJ-medium with the indirect proportion method.

RESULTS

Cultures were positive in 86/105 (82%) of newly diagnosed smear positive pulmonary TB cases. All of the 86 isolates were confirmed as M. tuberculosis. The majority (76.7%) of them were clustered into seven groups while the rest (23.3%) appeared unique. The most predominant Spoligotypes were SIT53 and SIT149, consisting of 24.4% and 20.9% of the isolates, respectively. Assigning of the isolates to family using SPOTCLUST software revealed that 45.3% of the isolates belonged to T1, 23.3% to T3 and 13% to CAS family. The majority (76.7%) of the M. tuberculosis isolates were susceptible to all the four drugs. Any resistance to any one of the four drugs was detected in 23.3% of the isolates. The highest proportion of any resistance was observed against isoniazid (9.3%) and ethambutol (7%). There was only a single case (1.2%) of multidrug resistant/rifampicin resistant (MDR/RR) TB.

CONCLUSION

The majority of the isolates were clustered suggesting on-going active transmission in the study area. Mono resistance is relatively prevalent while the magnitude of MDR/RR-TB was found to be lower than in previous studies.

Trends in prevalence of multi drug resistant tuberculosis in sub-Saharan Africa: A systematic review and meta-analysis

Background

Multidrug resistant tuberculosis (MDR-TB), is an emerging public health problem in sub-Saharan Africa (SSA). This study aims to determine the trends in prevalence of MDR-TB among new TB cases in sub-Saharan Africa over two decades.

Methods

We searched electronic data bases and accessed all prevalence studies of MDR-TB within SSA between 2007 and 2017. We determined pooled prevalence estimates using random effects models and determined trends using meta-regression.

Results

Results: We identified 915 studies satisfying inclusion criteria. Cumulatively, studies reported on MDR-TB culture of 34,652 persons. The pooled prevalence of MDR-TB in new cases was 2.1% (95% CI; 1.7–2.5%). There was a non-significant decline in prevalence by 0.12% per year.

Conclusion

We found a low prevalence estimate of MDR-TB, and a slight temporal decline over the study period. There is a need for continuous MDR-TB surveillance among patients with TB.

Multidrug resistant tuberculosis in Ethiopian settings and its association with previous history of anti-tuberculosis treatment: a systematic review and meta-analysis

Background

Efforts to control the global burden of tuberculosis (TB) have been jeopardized by the rapid evolution of multi-drug resistant Mycobacterium tuberculosis (MTB), which is resistant to at least isoniazid and rifampicin. Previous studies have documented variable prevalences of multidrug-resistant tuberculosis (MDR-TB) and its risk factors in Ethiopia. Therefore, this meta-analysis is aimed, firstly, to determine the pooled prevalence of MDR-TB among newly diagnosed and previously treated TB cases, and secondly, to measure the association between MDR-TB and a history of previous anti-TB drugs treatment.

Methods

PubMed, Embase and Google Scholar databases were searched. Studies that reported a prevalence of MDR-TB among new and previously treated TB patients were selected. Studies or surveys conducted at national or sub-national level, with reported MDR-TB prevalence or sufficient data to calculate prevalence were considered for the analysis. Two authors searched and reviewed the studies for eligibility and extracted the data in pre-defined forms. Forest plots of all prevalence estimates were performed and summary estimates were also calculated using random effects models. Associations between previous TB treatment and MDR-MTB infection were examined through subgroup analyses stratified by new and previously treated patients.

Results

We identified 16 suitable studies and found an overall prevalence of MDR-TB among newly diagnosed and previously treated TB patients to be 2% (95% CI 1% - 2%) and 15% (95% CI 12% - 17%), respectively. The observed difference was statistically significant (P < 0.001) and there was an odds ratio of 8.1 (95% CI 7.5–8.7) for previously treated TB patients to develop a MDR-MTB infection compared to newly diagnosed cases. For the past 10 years (2006 to 2014) the overall MDR-TB prevalence showed a stable time trend.

Conclusions

The burden of MDR-TB remains high in Ethiopian settings, especially in previously treated TB cases. Previous TB treatment was the most powerful predictor for MDR-MTB infection. Strict compliance with anti-TB regimens and improving case detection rate are the necessary steps to tackle the problem in Ethiopia.

Molecular detection of multidrug-resistant tuberculosis among smear-positive pulmonary tuberculosis patients in Jigjiga town, Ethiopia

Background

Molecular methods that target drug resistance mutations are suitable approaches for rapid drug susceptibility testing to detect multidrug-resistant tuberculosis (MDR-TB). The aim of the study was to determine MDR-TB cases and to analyze the frequency of gene mutations associated with rifampicin (RIF) and/or isoniazid (INH) resistance of Mycobacterium tuberculosis among smear-positive pulmonary tuberculosis patients.

Methods

Institution-based cross-sectional study design was employed. Sputum specimens were collected, and using a pretested questionnaire, data for associated risk factors for drug resistance were collected from 105 consecutive smear-positive pulmonary tuberculosis patients in Karamara General Hospital. Specimens were transported to Harar Health Research and Regional Laboratory, Harar, where molecular drug susceptibility testing was performed using GenoType^® MTBDRplus assay.

Results

Of the total 105 sputum specimens, 98 (93.3%) gave interpretable results, in which 67 (68.4%) were new cases and 31 (31.6%) were previously treated cases. Of these, 80 (81.6%) were sensitive to both drugs and 18 (18.4%) were resistant to RIF and/or INH. The prevalences of MDR-TB in total cases, new, and previously treated cases were 10 (10.2%), 3 (4.5%), and 7 (22.6%), respectively. Among the ten total RIF-resistant specimens, eight (80%) had resulted because of absence of rpoB WT8 and presence of MUT3 and in all specimens, the amino acids changed were Ser531Lue. Of the 18 total INH-resistant specimens, 15 (83.3%) had mutations in the katG gene (katG MUT1, Ser315Thr1), indicating high-level resistance, while 3 (14.7%) had mutations in the inhA promoter gene (Cys15Thr), indicating low-level resistance.

Conclusion

Among the mutations associated with resistance to RIF and INH, the majority were in codon 531 of the rpoB gene and codon 315 of the katG gene. Relatively high prevalence of MDR-TB was observed in the study.

Mycobacterium tuberculosis in central Ethiopia: drug sensitivity patterns and association with genotype

Drug resistance tuberculosis (TB) and the emergence of multidrug resistant (MDR) isolates are significant concerns regarding TB control programs in several countries. This study was undertaken to evaluate the drug sensitivity of Mycobacterium tuberculosis and to assess its association with strains and lineages of M. tuberculosis. A total of 279 M. tuberculosis strains isolated from Central Ethiopia were tested for their drug sensitivity patterns to first line TB drugs using the conventional proportion method on Löwenstein Jensen media. The association between drug sensitivity and strain type was assessed on 263 isolates of the 279 isolates. Of the 268 M. tuberculosis isolates obtained from new cases, 209 (78%) were susceptible to first line TB drugs, and 59 (22.2%) bacterial isolates were resistant to at least one of the first line drugs. The highest mono-resistance (7.5%) pertained to streptomycin (STM). Remarkably, seven of eleven isolates (63.6%) previous treatment for TB were resistant to at least one of the first line drugs. The prevalence of MDR-TB was 1.5% (4/268) for newly identified TB cases, all of which were members of the Euro-American Lineage. There was no statistically significant association (P > 0.05) between drug sensitivity, and either strains, sub-lineages or main lineages of M. tuberculosis. A significant proportion of M. tuberculosis was resistant to at least one first line anti-TB drug. Moreover, the frequencies of resistance to either isoniazid or rifampicin were high compared to data that were previously reported in some part of the country.

Rifampicin-resistance pattern of Mycobacterium tuberculosis and associated factors among presumptive tuberculosis patients referred to Debre Markos Referral Hospital, Ethiopia: a cross-sectional study

BACKGROUND

Prevailing data on rifampicin-resistant M. tuberculosis is essential for early management of MDR-TB. Therefore, this study was conducted to determine the prevalence of rifampicin-resistant Mycobacterium tuberculosis and associated factors among presumptive TB cases in Debre Markos Referral Hospital, Ethiopia.

METHODS

A cross-sectional study was conducted from September 2014 to March 2015. Detection of M. tuberculosis and resistance to rifampicin was performed using Gene Xpert MTB/RIF assay. Data was collected using structured questionnaire by face to face interview. Logistic regression analysis was computed to determine the associated factors of rifampicin-resistant M. tuberculosis.

RESULTS

A total of 505 presumptive TB patients included in the study. The prevalence of M. tuberculosis confirmed cases was 117 (23.2%) (95% CI 19.7-27%). It was higher among males (27.9%) than females (17.9%) (AOR: 2.17; CI 1.35-3.49). Of the 117 M. tuberculosis confirmed cases, 12 (10.3%) (95% CI 6.0-17.1%) were resistant to rifampicin. Rifampicin-resistant M. tuberculosis was noticed in 7 previously treated TB patients (17.1%) and 5 treatment naive patients (6.7%) (AOR: 4.16; CI 1.04-16.63). The prevalence of rifampicin-resistant M. tuberculosis was 6 (9.8%) and 6 (11.3%) in pulmonary and extra-pulmonary infections, respectively. Of the 30, MTB/HIV co-infection, 3 (10%) were rifampicin-resistant M. tuberculosis.

CONCLUSION

Rifampicin-resistant M. tuberculosis is prevalent in both pulmonary and extra-pulmonary tuberculosis patients. Previous treatment with anti-TB drugs was significantly associated with rifampicin resistance. Therefore, the use of Gene Xpert should be scaled up across the country for rapid detection and management of drug resistant M. tuberculosis.

Isoniazid Mono-Resistant Tuberculosis: Impact on Treatment Outcome and Survival of Pulmonary Tuberculosis Patients in Southern Mexico 1995-2010

Background

Isoniazid mono-resistance (IMR) is the most common form of mono-resistance; its world prevalence is estimated to range between 0.0 to 9.5% globally. There is no consensus on how these patients should be treated.

Objective

To describe the impact of IMR tuberculosis (TB) on treatment outcome and survival among pulmonary TB patients treated under programmatic conditions in Orizaba, Veracruz, Mexico.

Materials and Methods

We conducted a prospective cohort study of pulmonary TB patients in Southern Mexico. From 1995 to 2010 patients with acid-fast bacilli or culture proven Mycobacterium tuberculosis in sputum samples underwent epidemiological, clinical and microbiological evaluation. We included patients who harbored isoniazid mono-resistant (IMR) strains and patients with strains susceptible to isoniazid, rifampicin, ethambutol and streptomycin. All patients were treated following Mexican TB Program guidelines. We performed annual follow-up to ascertain treatment outcome, recurrence, relapse and mortality.

Results

Between 1995 and 2010 1,243 patients with pulmonary TB were recruited; 902/1,243 (72.57%) had drug susceptibility testing; 716 (79.38%) harbored pan-susceptible and 88 (9.75%) IMR strains. Having any contact with a person with TB (adjusted odds ratio (aOR)) 1.85, 95% Confidence interval (CI) 1.15–2.96) and homelessness (adjusted odds ratio (aOR) 2.76, 95% CI 1.08–6.99) were associated with IMR. IMR patients had a higher probability of failure (adjusted hazard ratio (HR) 12.35, 95% CI 3.38–45.15) and death due to TB among HIV negative patients (aHR 3.30. 95% CI 1.00–10.84). All the models were adjusted for socio-demographic and clinical variables.

Conclusions

The results from our study provide evidence that the standardized treatment schedule with first line drugs in new and previously treated cases with pulmonary TB and IMR produces a high frequency of treatment failure and death due to tuberculosis. We recommend re-evaluating the optimal schedule for patients harboring IMR. It is necessary to strengthen scientific research for the evaluation of alternative treatment schedules in similar settings.

Drug susceptibility profiles of pulmonary Mycobacterium tuberculosis isolates from patients in informal urban settlements in Nairobi, Kenya

Background

Anti-tuberculosis drug resistance is an emerging health problem in Kenya and especially in slums. Slum environments create a conducive environment for the spread of tuberculosis (TB) due to high population density and lack of basic amenities such as decent housing, access to clean water, lack of drainage and basic sanitation. Furthermore, ineffective health services in crowded and poorer populations, poor patient compliance, a large pool of untreated cases, delayed diagnosis and inappropriate treatment regimens are likely to favour selection and spread of drug resistant Mycobacterium tuberculosis (Mtb) strains in such settings, however, precise data on this problem are only sparsely available. To address this question, this study aimed at determining drug resistance patterns of Mtb strains obtained from pulmonary TB patients who sought health care in randomly selected informal settings.

Methods

This is a cross-sectional study conducted between September 2014 and March 2015, sputum samples were collected from 223 consenting adult patients and subjected to primary isolation and drug susceptibility testing. Socio-demographic data was collected and all data analysed using SPSS v20.

Results

Drug susceptibility testing against first line drugs was successfully carried out on 184 isolates. Resistance to at-least one drug was observed in 33 % of the isolates. The highest prevalence of resistance to any drug was identified against isoniazid,(INH) (23.9 %) followed by Ethambutol (EMB) (13.6 %). The highest proportion of mono resistance was observed against INH, 25 (13.6 %). Multidrug resistance (MDR) was observed in 4.4 % of the new cases. There was no significant difference in the proportion of any resistance by sex, age or previous treatment.

Conclusion

Levels of drug resistance have reached an alarming level in this population. Capacity of laboratories to conduct TB culture and DST should be strengthened in order to adequately manage TB patients and stop further creation and spread of MDR TB.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1920-5) contains supplementary material, which is available to authorized users.

Primary and secondary anti-tuberculosis drug resistance in Hitossa District of Arsi Zone, Oromia Regional State, Central Ethiopia

Background

Multidrug-resistant tuberculosis (MDR-TB) drugs which is resistant to the major first-line anti-TB drugs, Isoniazid and Rifampicin, has become a major global challenge in tuberculosis (TB) control programme. However, its burden at community level is not well known. Thus, the aim of study was to assess the prevalence of primary and secondary resistance to any first line anti-TB drugs and MDR TB in Hitossa District of Oromia Regional State, Central Ethiopia.

Methods

Population based cross- sectional study was conducted on individuals aged ≥15 years. Those with symptoms suggestive of TB were interviewed and two sputum specimens were collected from each and examined using Lowenstein-Jensen (LJ) culture medium. Further, the isolates were confirmed by the Ziehl-Neelsen microscopic examination method. Drug susceptibility test (DST) was also conducted on LJ medium using a simplified indirect proportion method. The resistance strains were then determined by percentage of colonies that grew on the critical concentration of Isoniazid, Streptomycin, Rifampicin and Ethambutol.

Results

The overall resistance of all forms of TB to any first-line anti-TB drug was 21.7 %. Of the total new and previously treated culture positive TB cases, 15.3 and 48.8 % respectively were found to be a resistant to any of the first-line anti-TB drugs. Further, of all forms of TB, the overall resistance of MDR-TB was 4.7 %. However, of the total new TB cases, 2.4 % had primary while 14.3 % had secondary MDR-TB. Resistance to any of the first-line anti-TB drugs (adjusted odd ratio (AOR), 8.1; 95 % CI: 2.26–29.30) and MDR-TB (AOR), 7.1; 95 % CI: 2.6–43.8) was found to be linked with previous history of anti-TB treatment.

Conclusions

The study has identified a high rate of primary and secondary resistance to any of the first-line anti-TB drugs and MDR-TB in the study area. The resistance may have resulted from sub-optimal performance of directly observed treatment short-course (DOTS) programme in the detecting infectious TB cases and cure rates in the study area. Anti-TB drug resistance is linked with previous TB treatment. There is a need to strengthen DOTS and DOTS-Plus programmes and expand MDR-TB diagnostic facilities in order to timely diagnose MDR-TB cases and provide appropriate treatment to prevent the spread of MDR-TB in Ethiopia.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3210-y) contains supplementary material, which is available to authorized users.

Drug resistance-conferring mutations in Mycobacterium tuberculosis from pulmonary tuberculosis patients in Southwest Ethiopia

OBJECTIVE/BACKGROUND

The nature and frequency of mutations in rifampicin (RIF) and isoniazid (INH) resistant Mycobacterium tuberculosis isolates vary considerably according to geographic locations. However, information regarding specific mutational patterns in Ethiopia remains limited.

METHODS

A cross-sectional prospective study was carried out among confirmed pulmonary tuberculosis cases in Southwest Ethiopia. Mutations associated with RIF and INH resistances were studied using GenoType MTBDRplus line probe assay in 112 M. tuberculosis isolates. Culture (MGIT960) and identification tests were performed at the Mycobacteriology Research Center of Jimma University, Jimma, Ethiopia.

RESULTS

Mutations conferring resistance to INH, RIF, and multidrug resistance were detected in 36.6% (41/112), 30.4% (34/112), and 27.7% (31/112) of M. tuberculosis isolates respectively. Among 34 RIF-resistant isolates, 82.4% (28/34) had rpoB gene mutations at S531L, 2.9% (1/34) at H526D, and 14.7% (5/34) had mutations only at wild type probes. Of 41 INH-resistant strains, 87.8% (36/41) had mutations in the katG gene at Ser315Thr1 and 9.8% (4/41) had mutations in the inhA gene at C15T. Mutations in inhA promoter region were strongly associated with INH monoresistance.

CONCLUSION

A high rate of drug resistance was commonly observed among failure cases. The most frequent gene mutations associated with the resistance to INH and RIF were observed in the codon 315 of the katG gene and codon 531 of the rpoB gene, respectively. Further studies on mutations in different geographic regions using DNA sequencing techniques are warranted to improve the kit by including more specific mutation probes in the kit.

Multidrug-resistant Mycobacterium tuberculosis and associated risk factors in Oromia Region of Ethiopia

OBJECTIVE

The aim of this study was to determine risk factors for tuberculosis (TB) caused by multidrug-resistant Mycobacterium tuberculosis (MDR-TB) in Oromia Region, Ethiopia.

METHODS

A 6-month case-control study was performed in 2013-14. Sputum samples and standardized questionnaire data (demographics, treatment, TB contact history, underlying disease, history of imprisonment) were collected from cases with suspected MDR-TB aged ≥ 18 years. Sputum was processed locally in the Oromia Public Health Laboratory using standard techniques. Data from MDR-TB cases and TB-positive controls were compared using logistic regression analysis. For each factor, the association with outcome variables was estimated by calculating the odds ratio (OR) together with the 95% confidence interval (95% CI).

RESULTS

Of 439 suspected MDR-TB cases, 265 had a confirmed M. tuberculosis infection, of whom 88 (33%) had laboratory-confirmed MDR-TB. Over two-thirds (65%) were between 18 and 39 years of age. On multivariate analysis, an occupation of farming, known TB contact history, alcohol use, HIV infection, previous known TB history, and previous TB treatment outcome were predictors of MDR-TB.

CONCLUSIONS

The rate of MDR-TB was high among suspected cases in the Oromia Region of Ethiopia. Local MDR-TB detection capacity and local epidemiology studies are essential to detect MDR-TB and guide the use of the sparse resources to optimize MDR-TB control. If TB is suspected, the presence of any of the above factors should alert Oromia Region clinicians and public health professionals to screen for MDR-TB.

Drug resistance patterns of Mycobacterium tuberculosis complex and associated factors among retreatment cases around Jimma, Southwest Ethiopia

Background

Information on the pattern of drug resistant tuberculosis (TB) among re-treatment cases is crucial to develop appropriate control strategies. Therefore, we conducted this study to assess the drug resistance pattern of M. tuberculosis complex (MTBC) isolates and associated factors among re-treatment cases in Jimma area, Southwest Ethiopia.

Methods

Health facility-based cross-sectional study was conducted between March 2012 and April 2013 in Jimma area, Southwest Ethiopia. We included 79 re-treatment cases selected conveniently. Socio demographic and clinical data were collected using structured questionnaire. Sputum sample processing, mycobacterial culture, isolation and drug susceptibility testing (DST) were done at Mycobacteriology Research Centre (MRC) of Jimma University. All data were registered and entered in to SPSS version 20. Crude odds ratio (COR) and adjusted odds ratios (AOR) were calculated. P-values less than 0.05 were considered statistically significant.

Results

Seventy-nine re-treatment cases included in the study; 48 (60.8 %) were males. Forty- seven (59.5 %) study participants were from rural area with the mean age of 31.67 ± 10.02 SD. DST results were available for 70 MTBC isolates. Majority (58.6 % (41/70)) isolates were resistant to at least one of the four first line drugs. The prevalence of multidrug-resistant TB (MDR-TB) was 31.4 % (22/70). Place of residence (AOR = 3.44 (95 % CI: 1.12, 10.60), duration of illness (AOR = 3.00 (95 % CI: 1.17, 10.69) and frequency of prior TB therapy (AOR = 2.99, (95 % CI: 1.01, 8.86) were significant factors for any drug resistance. Moreover, history of treatment failure was found to be associated with MDR-TB (AOR = 3.43 (95 % CI: 1.14, 10.28).

Conclusion

The overall prevalence of MDR-TB among re-treatment cases around Jimma was high. The rate of MDR-TB was higher in patients with the history of anti-TB treatment failure. Timely identification and referral of patients with the history of treatment failure for culture and DST need to be strengthened.

Prevalence and drug resistance profile of Mycobacterium tuberculosis isolated from pulmonary tuberculosis patients attending two public hospitals in East Gojjam zone, northwest Ethiopia

BACKGROUND

The spread of multidrug-resistant tuberculosis (MDR-TB) strains has become a challenge to the global TB control and prevention program. In Ethiopia, particularly in rural areas, information on drug-resistant TB is very limited. In this study, we determined the drug resistance patterns of Mycobacterium tuberculosis (M. tuberculosis) isolates from pulmonary TB patients attending two public hospitals in the East Gojjam zone of northwest Ethiopia.

METHODS

A cross-sectional study was conducted between May 2011 and January 2012 using Region of difference-9 (RD9) typing for the identification of species mycobacterium. Drug susceptibility testing (DST) of M. tuberculosis isolates to the first-line drugs: isoniazid, rifampicin, ethambutol and streptomycin was performed by the indirect proportion method on Middle brook 7H10 Agar media.

RESULTS

Out of 385 pulmonary TB suspects studied, 124 (32.2%) were culture positive among which 120 were M. tuberculosis strains. Susceptibility testing was performed for 89 isolates. Resistance to at least one drug was 15.58% ([12/77], 95% CI: 7.48-23.68) among newly diagnosed and 50.0% ([6/12], 95% CI: 21.71-78.29) among previously treated cases. Resistance among newly diagnosed patients was most common for streptomycin 5.19% (4/77) and ethambutol 5.19% (4/77) followed by rifampicin 3.89% (3/77). Among retreatment cases, isoniazid resistance was most frequent in which 33.33% (4/12) of the isolates were resistant. MDR prevalence was 1.29% (1/77) for newly diagnosed and 16.67% (2/12) for retreatment cases. In a multivariate logistic regression analysis, age group of 25-34 years (adjusted OR = 4.24; 95% CI: 1.02-17.5; P = 0.046) and previous history of treatment (adjusted OR = 5.42; 95% CI: 1.56-27.49; P = 0.01) were independently associated with anti-TB drug resistance.

CONCLUSIONS

In general, the magnitude of anti-TB drug resistance including MDR-TB was comparable to previous studies in other areas of Ethiopia. However, rifampicin resistance was high, which could suggest the potential for a rise in the incidence of MDR. Therefore, re-enforcing TB control programs should be considered by the concerned public health authorities.

A meta-analysis of drug resistant tuberculosis in Sub-Saharan Africa: how strongly associated with previous treatment and HIV co-infection?

Background

In Sub-Saharan Africa, the fight against tuberculosis (TB) has encountered a great challenge because of the emergence of drug resistant TB strains and the high prevalence of HIV infection. The aim of this meta-analysis was to determine the association of drug-resistant TB with anti-TB drug treatment history and HIV co-infection.

Methods

After electronic based literature search in the databases of Medline, HINARI, EMBASE and the Cochrane library, article selection and data extraction were carried out. HIV co-infection and previous history of TB treatment were used as predictors for the occurrence of any anti-TB drug resistant or multiple drug resistant TB (MDR-TB). The risk ratios for each included study and for the pooled sample were computed using the random-effects model. Heterogeneity test, sensitivity analyses and funnel plots were also done.

Results

The pooled analysis showed that the risk of developing drug-resistant TB to at least one anti-TB drug was about 3 times higher in individuals who had a previous history of anti-TB treatment than new TB cases. The risk of having MDR-TB in previously anti-TB treated TB cases was more than 5-fold higher than that of new TB cases. Resistance to Ethambutol and Rifampicin was more than fivefold higher among the previously treated with anti-TB drugs. However, HIV infection was not associated with drug-resistant TB.

Conclusion

There was a strong association of previous anti-TB treatment with MDR-TB. Primary treatment warrants special emphasis, and screening for anti-TB drugs sensitivity has to be strengthened.

Multidrug-resistant tuberculosis in Ethiopia: efforts to expand diagnostic services, treatment and care

The emergence of drug-resistant tuberculosis (TB), particularly multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB, is a major public health problem. The purpose of this review is to describe the current status of MDR-TB and factors that increase the risk of this infection. We conducted a systematic review of the literature on MDR-TB in Ethiopia. Out of 766 articles, 23 were found to meet eligibility criteria and included in this review. Among the 23 papers, six of them reported high prevalence of MDR-TB in the range of 3.3%-46.3%. Likewise, two studies reported XDR-TB in the range of 1% - 4.4% in Ethiopia. The most powerful predictor of the emergence of MDR-TB reported in Ethiopia is previous exposure to anti-TB drug treatment. This review indicated that MDR-TB in Ethiopia is a serious public health problem that needs to be addressed urgently. Strengthening early case detection and proper treatment of drug-susceptible TB in accordance with World Health Organization (WHO) treatment guidelines to ensure adequate treatment success rates is critical. Consequently, efforts have been made to a rapidly increase MDR-TB diagnosis as well as the number of treatment sites to implement a directly observed treatment, short-course (DOTS) plus strategy to interrupt transmission of MDR-TB.

Fifteen-year trend in treatment outcomes among patients with pulmonary smear-positive tuberculosis and its determinants in Arsi Zone, Central Ethiopia

BACKGROUND

Directly Observed Treatment Short course (DOTS) strategy is aimed at diagnosing 70% of infectious tuberculosis (TB) and curing 85% of it. Arsi Zone of Ethiopia piloted DOTS strategy in 1992. Since then, the trend in treatment outcomes in general and at district-level in particular has not been assessed. The aim of this study was to analyse the trend in TB treatment outcomes and audit district-level treatment outcomes in the 25 districts of Arsi Zone.

DESIGN

A retrospective cohort study design was employed to audit pulmonary smear-positive (PTB + ) patients registered between 1997 and 2011. Demographic and related data were collected from the TB unit registers between January and March 2013. The 15-year trend in treatment outcomes among PTB+ patients and district-level treatment outcomes was computed.

RESULTS

From 14,221 evaluated PTB+ cases, 11,888 (83.6%) were successfully treated. The treatment success rate (TSR) varied from 69.3 to 92.5%, defaulter rate from 2.5 to 21.6%, death rate from 1.6 to 11.1%, and failure rate from 0 to 3.6% across the 25 districts of the zone. The trend in TSR increased from 61 to 91% with the increase of population DOTS coverage from 18 to 70%. There was a declining trend in defaulter rate from 29.9 to 2.1% and death rate from 8.8 to 5.4% over 15 years. Patients aged 25-49 years (Adjusted Odd Ratio (AOR), 0.23; 95% CI: 0.21-0.26) and ≥50 years (AOR, 0.43; 95% CI: 0.32-0.59), re-treatment cases (AOR, 0.61; 0.41, 0.67), and TB/HIV co-infection cases (AOR, 0.45; 95% CI: 0.31-0.53) were associated with unsuccessful treatment outcomes.

CONCLUSIONS

DOTS expansion and improving population DOTS coverage in Arsi has led to a significant increase in treatment success and decrease in death and defaulter rates. However, there is a major variation in treatment outcomes across the 25 districts of the zone, so district-specific intervention strategy needs to be considered. The low TSR among re-treatment cases might be due to the high rate of MDR-TB among this group, and the issue needs to be further investigated to identify the extent of the problem.

Prevalence and Drug Resistance Patterns of Mycobacterium tuberculosis among New Smear Positive Pulmonary Tuberculosis Patients in Eastern Ethiopia

The study aimed at determining the prevalence and drug resistance patterns of Mycobacterium tuberculosis among new smear positive pulmonary tuberculosis patients visiting TB diagnosis and treatment facilities at selected health facilities in eastern Ethiopia. A cross-sectional study was conducted between October 2011 and May 2013. A total of 408 new adult pulmonary TB patients (≥ 18 years) were enrolled in this study. Three consecutive sputum samples (spot, morning, and spot) were collected from each patient and transported to the Armauer Hansen Research Institute TB laboratory located in Addis Ababa for culture on Lowenstein Jensen slant media. DST was performed on 357 (87.5%) of the patient samples for isoniazid (H), rifampicin (R), ethambutol (E), and streptomycin (S) using the standard proportion method. The rate of resistance to any one drug was 23%. Any resistance to H, S, R, and E was 14%, 11.5%, 2.8%, and 0.3%, respectively. The highest proportion of monoresistance was observed against H (9.5%). MDRTB was detected in 1.1% of the patients. Any drug resistance was associated with HIV infection (COR = 3.7, 95% CI 1.905-7.222) (P = 0.000). Although the prevalence of MDRTB is relatively low in the study area, high prevalence of H resistance is a serious concern demanding close monitoring. Expanding diagnostic capacity for mycobacterial culture and DST is a vital step in this regard.

Genotype diversity of Mycobacterium isolates from children in Jimma, Ethiopia

BACKGROUND

Paediatric tuberculosis (TB) is poorly addressed in Ethiopia and information about its magnitude and the genotype distribution of the causative Mycobacterium tuberculosis strains responsible for its spread are scanty.

METHODS

Gastric lavage or sputum samples were collected from consecutively enrolled TB suspect children visiting Jimma University Hospital in 2011 and cultured on Middlebrook 7H11 and Löwenstein-Jensen media. Acid fast bacterial (AFB) isolates were subjected to molecular typing targeting regions of difference (RDs), 16S rDNA gene and the direct repeat (DR) region using multiplex polymerase chain reaction (mPCR), gene sequencing and spoligotyping, respectively. Molecular drug susceptibility testing of M. tuberculosis isolates was performed by Genotype®MTBDRplus line probe assay (LPA) (Hain Life Sciences, Germany).

RESULTS

Gastric lavage (n = 43) or sputum (n = 58) samples were collected from 101 children and 31.7% (32/101) of the samples were positive for AFB by microscopy, culture and/or PCR. Out of 25 AFB isolates, 60% (15/25) were identified as M. tuberculosis by PCR, and 40% isolates (10/25) were confirmed to be non-tuberculous mycobacteria (NTM) by genus typing and 16S rDNA gene sequencing. Lineage classification assigned the M. tuberculosis strains into Euro-American (EUA, 66.7%; 10/15), East-African-Indian (EAI; 2/15), East-Asian (EA; 1/15) and Indio-Oceanic (IO; 1/15) lineages. Seven M. tuberculosis strains were new to the SpolDB4 database. All of the M. tuberculosis isolates were susceptible to isoniazid (INH) and rifampicin (RIF), except for one strain (of spoligotype SIT-149 or T3_ETH family) which had a mutation at the inhA locus which often confers resistance to INH (low level) and ethionamide.

CONCLUSIONS

Analysis of the genetic population structure of paediatric M. tuberculosis strains suggested similarity with that of adults, indicating an on-going and active transmission of M. tuberculosis from adults to children in Ethiopia. There were no multidrug-resistant TB (MDR-TB) strains among the isolates.