Prevalence of rifampicin resistant tuberculosis and associated factors among presumptive tuberculosis patients in a secondary referral hospital in Lagos Nigeria

Trends of Mycobacterium tuberculosis and rifampicin resistance at the Ho Teaching Hospital in Ghana

BACKGROUND

Tuberculosis remains a major public health threat worldwide, causing significant morbidity and mortality, particularly in low- and middle-income countries. In recent years, efforts to combat tuberculosis have focused on strengthening healthcare systems and increasing access to diagnostics and treatment services. There is scarcity of data on the prevalence of Mycobacterium tuberculosis and rifampicin-resistant tuberculosis in the Volta region of Ghana. Therefore, the aim of this study was to determine the trends of Mycobacterium tuberculosis and rifampicin resistance in a major teaching hospital in Ghana spanning a six-year period.

METHODOLOGY

A retrospective cross-sectional hospital study was conducted at Ho Teaching Hospital, Ho, Ghana. Study data included archived results on tuberculosis testing using GeneXpert from 2016-2021. Archived data on tuberculosis testing were collected and entered using Microsoft Excel 2019. IBM SPSS (v26) was used for a statistical analysis of the prevalence of tuberculosis. P-value <0.05 was considered statistically significant.

RESULTS

The study included 5128 presumptive tuberculosis cases from 2016 to 2021, of which 552 were positive, revealing an overall prevalence of 10.76%. Males exhibited a significantly higher prevalence of tuberculosis (14.20%) compared to females (7.48%), with a male-to-female ratio of 2:1. The burden of tuberculosis varied significantly between age groups, with those aged 30-45 years and 46-60 years facing twice the risk compared to those under 15 years (p<0.001). Rainy seasons correlated with heightened tuberculosis occurrences (12.12%) compared to dry seasons (8.84%) (p = 0.008). Rifampicin-resistant tuberculosis was prevalent at 3.45%, slightly higher in women, particularly in the 45-59 age group (5.97%). In particular, tuberculosis prevalence exhibited fluctuations, peaking in 2016 (17.1%) and 2020 (11.5%), with a trough in 2019 (4.6%).

CONCLUSION

The overall prevalence of laboratory confirmed tuberculosis was 10.76%, and resistance to rifampicin, 3.45%, indicating high infection and possible treatment failure. Considering its infectious nature, this calls for concerted efforts to curb the spread of the infection.

Molecular detection of rifampicin-resistant Mycobacterium tuberculosis by polymerase chain reaction in Ethiopia: a systematic review and meta-analysis

Introduction

Tuberculosis is a contagious bacterial disease caused by Mycobacterium tuberculosis. The emergence and spread of drug-resistant strains of M. tuberculosis in both developing and developed countries has made diagnosis, treatment, and control of tuberculosis more difficult. The PCR assay, which is a fast and sensitive technique and an alternative method for detecting multidrug-resistant tuberculosis, is used to determine rifampicin (RIF) resistance. There is no single figure in Ethiopia that represents rifampicin-resistant tuberculosis and that is why this study was conducted to overcome the inconsistency of the results of the previous studies.

Methods

Studies were researched from five major electronic databases. Studies which were cross-sectional in design, published, and written in English were included. The data were extracted using Microsoft Excel, and the data were managed and analyzed using Stata™ Version 17.0 statistical software. The Forest plot was used to check the presence of heterogeneity. The publication bias, meta-regression, and subgroup analysis were used to find out the source of heterogeneity. A random effect analysis model was used to pool the prevalence of RR TB from primary studies, and associated factors of RR among TB patients were identified using Meta regression. The presence of association was reported using OR with 95% CI.

Results

The overall pooled prevalence of tuberculosis was 14.9% (95% CI: 13.34, 16.46), of these approximately 7.48% (95% CI: 6.30, 8.66) showed rifampicin-resistant tuberculosis in Ethiopia. Among the computed variables, 2.05% living with HIV1.39 (95%CI: 1.13, 1.72) and having a history of TB treatment (95%CI: 1.34, 3.15) were identified as significant factors associated with RR TB in Ethiopia.

Conclusion

Drug-resistant TB is one of the prevalent emerging infectious diseases among TB patients, which affects approximately one out of every thirteen TB patients. Having TB-HIV coinfection and a history of prior TB treatment were identified as significant factors associated with RR TB. To prevent and control RR TB, patients should complete their follow-up course; the health professionals should educate the actions taken by the patients when they experience drug toxicity and side effects; and the Minister of Health should initiate telemedicine and recruit tracers to overcome TB patients' default and have good drug adherence and retention after initiation of the treatment.

The Role of Trust as a Driver of Private-Provider Participation in Disease Surveillance: Cross-Sectional Survey From Nigeria

BACKGROUND

Recognition of the importance of valid, real-time knowledge of infectious disease risk has renewed scrutiny into private providers' intentions, motives, and obstacles to comply with an Integrated Disease Surveillance Response (IDSR) framework. Appreciation of how private providers' attitudes shape their tuberculosis (TB) notification behaviors can yield lessons for the surveillance of emerging pathogens, antibiotic stewardship, and other crucial public health functions. Reciprocal trust among actors and institutions is an understudied part of the "software" of surveillance.

OBJECTIVE

We aimed to assess the self-reported knowledge, motivation, barriers, and TB case notification behavior of private health care providers to public health authorities in Lagos, Nigeria. We measured the concordance between self-reported notification, TB cases found in facility records, and actual notifications received.

METHODS

A representative, stratified sample of 278 private health care workers was surveyed on TB notification attitudes, behavior, and perceptions of public health authorities using validated scales. Record reviews were conducted to identify the TB treatment provided and facility case counts were abstracted from the records. Self-reports were triangulated against actual notification behavior for 2016. The complex health system framework was used to identify potential predictors of notification behavior.

RESULTS

Noncompliance with the legal obligations to notify infectious diseases was not attributable to a lack of knowledge. Private providers who were uncomfortable notifying TB cases via the IDSR system scored lower on the perceived benevolence subscale of trust. Health care workers who affirmed "always" notifying via IDSR monthly reported higher median trust in the state's public disease control capacity. Although self-reported notification behavior was predicted by age, gender, and positive interaction with public health bodies, the self-report numbers did not tally with actual TB notifications.

CONCLUSIONS

Providers perceived both risks and benefits to recording and reporting TB cases. To improve private providers' public health behaviors, policy makers need to transcend instrumental and transactional approaches to surveillance to include building trust in public health, simplifying the task, and enhancing the link to improved health. Renewed attention to the "software" of health systems (eg, norms, values, and relationships) is vital to address pandemic threats. Surveys with private providers may overestimate their actual participation in public health surveillance.

Trends of Mycobacterium tuberculosis and Rifampicin resistance in Northwest Ethiopia: Xpert® MTB/RIF assay results from 2015 to 2021

BACKGROUND

Tuberculosis (TB) remains one of the leading causes of morbidity and mortality worldwide, particularly in countries with limited resources. The emergence of drug resistance in mycobacterium tuberculosis (MTB), particularly rifampicin (RIF) resistance, hindered TB control efforts. Continuous surveillance and regular monitoring of drug-resistant TB, including rifampicin resistance (RR), are required for effective TB intervention strategies and prevention and control measures.

OBJECTIVE

Determine the trend of TB and RR-TB among presumptive TB patients in Northwest Ethiopia.

METHOD

A retrospective study was conducted at the University of Gondar Comprehensive Specialized Hospital (UoG-CSH). The study included TB registration logbook data from all patients who visited the hospital and were tested for MTB using the Xpert® MTB/RIF assay between 2015 and 2021. The SPSS version 26 software was used to enter, clean, and analyze the laboratory-based data.

RESULTS

A total of 18,787 patient results were included, with 93.8% (17,615/18787) of them being successful, meaning they were not invalid, error, or aborted. About 10.5% (1846/17615) of the 17,615 results were MTB-positive, with 7.42% (137/1846) RIF resistant. Age, anti-TB treatment history, and diagnosis year were associated with the presence of MTB and RR-MTB. Tuberculosis (TB) prevalence was higher in productive age groups, whereas RR-TB prevalence was higher in the elderly. Regarding diagnosis year, the prevalence of TB and RR-TB showed a declining trend as the year progressed. While MTB was detected in 12.8% (471/3669) of new and 22.2% (151/679) of re-treatment presumptive TB patients, RR-MTB was detected in 8.5% (40/471) of new and 18.5% (28/151) of re-treatment TB cases.

CONCLUSION

The prevalence of TB and RR-TB in the study area showed a declining trend over the years. While TB was more prevalent in productive age groups (15 to 45 years), RR-TB was more prevalent in older populations (over 45 years), than others. Moreover, patients with a history of anti-TB drug exposure were more likely to be positive for DR-TB, highlighting the need to strengthen DOT programs for proper management of TB treatment.

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

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.

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.

High proportion of RR-TB and mutations conferring RR outside of the RRDR of the rpoB gene detected in GeneXpert MTB/RIF assay positive pulmonary tuberculosis cases, in Addis Ababa, Ethiopia

BACKGROUND

Globally, TB is the leading cause of infectious disease morbidity and mortality with many diagnostic uncertainties. Access to affordable and rapid diagnostics remained a major challenge for many developing countries which bear the greatest burden of TB delaying the initiation time to treatment.

OBJECTIVE

This study aimed to assess the GeneXpert MTBRIF assay probe utility for the detection of pulmonary TB and Rifampicin-resistant TB cases in Addis Ababa, Ethiopia.

MATERIALS AND METHODS

A cross-sectional study was performed from October 2019 to July 2020 in Saint Peter TB Specialized Hospital in Addis Ababa metropolitan area, Ethiopia. This study enrolled 216 clinically suspected new presumptive pulmonary TB cases confirmed by GeneXpert MTB/RIF Assay. Sociodemographic and clinical characteristics were captured using a structured tool. Data were entered in Microsoft Excel 2019, checked for inconsistency, cleaned promptly, and exported to IBM SPSS Statistics for Windows, Version 26.0. Armonk, N.Y: IBM Corp, the USA for analysis. Descriptive analysis and binary and multivariate logistics regression were performed and all statistical significance was determined at a 95% confidence level.

RESULTS

The majority of the study participants, 55.1% [119/216] were males aged 6-80 years. The prevalence of RR MTB was 11.11% [24/216]. A higher proportion of RR TB was found in female patients [54.2%, 13/24], in patients in the age group of 30-50 years [45.8%, 11/24], in married individuals [62.5%, 15/24], in persons whose residence is urban [79.2%, 19/24], in persons who had a previous history of TB symptoms [100%, 24/24], in persons who had a history of contact with active and LTBI [33.3%, 8/24], and in persons who had a history of HIV and IDUs [41.7%, 10/24]. Occupation (AOR 22.868, 95% CI 1.655-316.022, p = 0.019), history of previous PTB+ (AOR 4.222, 95% CI 1.020-17.47, p = 0.047), and history of HIV and IDUs (AOR 4.733, 95% CI 1.416-15.819, p = 0.012) were independent predictors associated with RR-TB emergence. The commonest mutation 62.5% [15/24] was found in probe E (codons 529-533) region. There was no mutation associated with probe A (codons 507-511), probe B (codons 511-518), and probe C (codons 518-523) regions, as well as no combination of missed probes, was revealed. However, 12.5% [3/24] of RR TB patients were found without unidentified missed probe types detected outside of the RRDR. The delta Ct max was >4.0 and the highest proportion of 35.6% [77/216] RR TB was detected in samples of medium DNA load.

CONCLUSION

The proportion of RR-TB we observed in this study was high. Similarly, a higher proportion of RR TB was detected outside of the RRDR. Moreover, a significant number of the GeneXpert MTB/RIF Assay probes were identified as unhybridized and this critical observation would mean that most of the probes had no or minimal utility in this geographical region. This calls for further studies to uncover mutation in the rpoB gene conferring RR and reshape TB triage and definite diagnostic algorithm in Ethiopia.

Tuberculosis Prevalence and Predictors Among Health Care-Seeking People Screened for Cough of Any Duration in Ethiopia: A Multicenter Cross-Sectional Study

Background

Tuberculosis (TB) remains a major cause of morbidity and mortality in sub-Saharan Africa. This high burden is mainly attributed to low case detection and delayed diagnosis. We aimed to determine the prevalence and predictors of TB among health care-seeking people screened for cough of any duration in Ethiopia.

Methods

In this multicenter cross-sectional study, we screened 195,713 (81.2%) for cough of any duration. We recruited a sample of 1,853 presumptive TB (PTB) cases and assigned them into three groups: group I with cough ≥2 weeks, group II with cough of <2 weeks, and group III pregnant women, patients on antiretroviral therapy, and patients with diabetes. The first two groups underwent chest radiograph (CXR) followed by sputum Xpert MTB/RIF assay or smear microscopy. The third group was exempted from CXR but underwent sputum Xpert MTB/RIF assay or smear microscopy. TB prevalence was calculated across the groups and TB predictors were analyzed using modified Poisson regression to compute adjusted prevalence ratio (aPR) with a 95% confidence interval (CI).

Results

The overall prevalence of PTB was 16.7% (309/1853). Of the positive cases, 81.2% (251/309) were in group I (cough ≥2 weeks), 14.2% (44/309) in group II (cough of <2), and 4.5% (14/309) in group III (CXR exempted). PTB predictors were age group of 25-34 [aPR = 2.0 (95% CI 1.3-2.8)], history of weight loss [aPR = 1.2 (95% CI 1.1-1.3)], and TB suggestive CXRs [aPR = 41.1 (95% CI 23.2-72.8)].

Conclusion

The prevalence of confirmed PTB among routine outpatients was high, and this included those with a low duration of cough who can serve as a source of infection. Screening all patients at outpatient departments who passively report any cough irrespective of duration is important to increase TB case finding and reduce TB transmission and mortality.

Prevalence of Mycobacterium tuberculosis infection and rifampicin resistance among presumptive tuberculosis cases visiting tuberculosis clinic of Adare General Hospital, Southern Ethiopia

Objective:

Multidrug-resistant Mycobacterium tuberculosis is a public health threat in resource-limited countries where it is easily disseminated and difficult to control. The aim of this study was to determine the prevalence of tuberculosis, rifampicin-resistant/multidrug-resistant Mycobacterium tuberculosis, and associated factors among presumptive tuberculosis cases attending the tuberculosis clinic of Adare General Hospital located in Hawassa city.

Methods:

A hospital-based cross-sectional study was conducted among 321 tuberculosis suspected patients from April to July 2018. Socio-demographic, environmental, and behavioral data were collected using a structured questionnaire. Sputum specimens were analyzed using GeneXpert. Data entry was made using Epi info version 7 and analyzed by SPSS version 20. Logistic regression models were used to determine the risk factors. A p-value less than 0.05 was taken as a cut point.

Results:

In this study, the prevalence of Mycobacterium tuberculosis was 98 (30.5%) with 95% confidence interval (25.5–35.8), and the prevalence of rifampicin-resistant/multidrug-resistant Mycobacterium tuberculosis among the 98 Mycobacterium tuberculosis confirmed cases was 4 (4.1%). The prevalence of rifampicin-resistant/multidrug-resistant Mycobacterium tuberculosis among the tuberculosis suspected patients was 1.24%. Participants who had a history of treatment with anti-tuberculosis drugs were more likely to develop rifampicin-resistant/multidrug-resistant Mycobacterium tuberculosis.

Conclusions:

This study identified relatively high rifampicin-resistant/multidrug-resistant Mycobacterium tuberculosis among tuberculosis suspected patients in the study area. Early detection of drug-resistant Mycobacterium tuberculosis should be given enough attention to strengthen the management of tuberculosis cases and improve direct observation therapy short-course and eventually minimize the spread of rifampicin-resistant tuberculosis strain in the community.

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.

INCIDENCE OF RIFAMPICIN-RESISTANCE PRESUMPTIVE M. TUBERCULOSIS CASES AMONG OUTPATIENTS IN KEBBI STATE, NIGERIA

Background:

The present study determined the incidence of rifampicin resistance M. tuberculosis among outpatients at the General Hospital Yauri, Kebbi State, Nigeria.

Materials and Methods:

The study is a cross-sectional study conducted from February 2018 to October 2019. Sociodemographic data were collected from hospital registration books. Rifampicin resistance M. tuberculosis was detected using GeneXpert Model GX-IV following manufacturers’ instruction. Descriptive statistics and logistic regression were computed using SPSS version 20. The results were presented as odds ratios with associated 95% confidence intervals, and P-value at 0.05.

Result:

Of the 837 samples, 65.8% (551/837) were males, and 34.2% (286/837) females, 11.4% (95/837) HIV-seropositive. M. tuberculosis was detected in 15.5% (130/837), of which 116/130 (89.23%) were males and 14/130 (10.77%) females. M. tuberculosis-HIV coinfection was detected in 9.47% (9/95) of HIV positive. Rifampicin resistance was observed in 1.3% (11/837), 7.7% (10/130) in M. tuberculosis patients and 1.05% (1/94) in HIV seropositive. In logistic regression, the odds ratio for having a rifampicin-resistant M. tuberculosis was 0.49 (0.15-1.54) for > 30 years; taking <30 years as the reference value, 1.02 (1.00-1.03) for male; taking female as the reference value, and 0.78 (0.09-6.15) for HIV positive, taking negative as the reference value.

Conclusion:

This study reported the current incidence rate of rifampicin-resistant M. tuberculosis at the General Hospital Yelwa Yauri, Kebbi State, Nigeria, among presumptive TB patients. Patients diagnosed with rifampicin-resistant M. tuberculosis were predominantly male adults. Thus, frequent screening is vital for surveillance and reduces the risk of transmission and spread of M. tuberculosis infections.

Xpert MTB/RIF and Xpert Ultra assays for screening for pulmonary tuberculosis and rifampicin resistance in adults, irrespective of signs or symptoms

BACKGROUND

Tuberculosis is a leading cause of infectious disease-related death and is one of the top 10 causes of death worldwide. The World Health Organization (WHO) recommends the use of specific rapid molecular tests, including Xpert MTB/RIF or Xpert Ultra, as initial diagnostic tests for the detection of tuberculosis and rifampicin resistance in people with signs and symptoms of tuberculosis. However, the WHO estimates that nearly one-third of all active tuberculosis cases go undiagnosed and unreported. We were interested in whether a single test, Xpert MTB/RIF or Xpert Ultra, could be useful as a screening test to close this diagnostic gap and improve tuberculosis case detection.

OBJECTIVES

To estimate the accuracy of Xpert MTB/RIF and Xpert Ultra for screening for pulmonary tuberculosis in adults, irrespective of signs or symptoms of pulmonary tuberculosis in high-risk groups and in the general population. Screening "irrespective of signs or symptoms" refers to screening of people who have not been assessed for the presence of tuberculosis symptoms (e.g. cough). To estimate the accuracy of Xpert MTB/RIF and Xpert Ultra for detecting rifampicin resistance in adults screened for tuberculosis, irrespective of signs and symptoms of pulmonary tuberculosis in high-risk groups and in the general population.

SEARCH METHODS

We searched 12 databases including the Cochrane Infectious Diseases Group Specialized Register, MEDLINE and Embase, on 19 March 2020 without language restrictions. We also reviewed reference lists of included articles and related Cochrane Reviews, and contacted researchers in the field to identify additional studies.

SELECTION CRITERIA

Cross-sectional and cohort studies in which adults (15 years and older) in high-risk groups (e.g. people living with HIV, household contacts of people with tuberculosis) or in the general population were screened for pulmonary tuberculosis using Xpert MTB/RIF or Xpert Ultra. For tuberculosis detection, the reference standard was culture. For rifampicin resistance detection, the reference standards were culture-based drug susceptibility testing and line probe assays.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data using a standardized form and assessed risk of bias and applicability using QUADAS-2. We used a bivariate random-effects model to estimate pooled sensitivity and specificity with 95% credible intervals (CrIs) separately for tuberculosis detection and rifampicin resistance detection. We estimated all models using a Bayesian approach. For tuberculosis detection, we first estimated screening accuracy in distinct high-risk groups, including people living with HIV, household contacts, people residing in prisons, and miners, and then in several high-risk groups combined.

MAIN RESULTS

We included a total of 21 studies: 18 studies (13,114 participants) evaluated Xpert MTB/RIF as a screening test for pulmonary tuberculosis and one study (571 participants) evaluated both Xpert MTB/RIF and Xpert Ultra. Three studies (159 participants) evaluated Xpert MTB/RIF for rifampicin resistance. Fifteen studies (75%) were conducted in high tuberculosis burden and 16 (80%) in high TB/HIV-burden countries. We judged most studies to have low risk of bias in all four QUADAS-2 domains and low concern for applicability. Xpert MTB/RIF and Xpert Ultra as screening tests for pulmonary tuberculosis In people living with HIV (12 studies), Xpert MTB/RIF pooled sensitivity and specificity (95% CrI) were 61.8% (53.6 to 69.9) (602 participants; moderate-certainty evidence) and 98.8% (98.0 to 99.4) (4173 participants; high-certainty evidence). Of 1000 people where 50 have tuberculosis on culture, 40 would be Xpert MTB/RIF-positive; of these, 9 (22%) would not have tuberculosis (false-positives); and 960 would be Xpert MTB/RIF-negative; of these, 19 (2%) would have tuberculosis (false-negatives). In people living with HIV (1 study), Xpert Ultra sensitivity and specificity (95% CI) were 69% (57 to 80) (68 participants; very low-certainty evidence) and 98% (97 to 99) (503 participants; moderate-certainty evidence). Of 1000 people where 50 have tuberculosis on culture, 53 would be Xpert Ultra-positive; of these, 19 (36%) would not have tuberculosis (false-positives); and 947 would be Xpert Ultra-negative; of these, 16 (2%) would have tuberculosis (false-negatives). In non-hospitalized people in high-risk groups (5 studies), Xpert MTB/RIF pooled sensitivity and specificity were 69.4% (47.7 to 86.2) (337 participants, low-certainty evidence) and 98.8% (97.2 to 99.5) (8619 participants, moderate-certainty evidence). Of 1000 people where 10 have tuberculosis on culture, 19 would be Xpert MTB/RIF-positive; of these, 12 (63%) would not have tuberculosis (false-positives); and 981 would be Xpert MTB/RIF-negative; of these, 3 (0%) would have tuberculosis (false-negatives). We did not identify any studies using Xpert MTB/RIF or Xpert Ultra for screening in the general population. Xpert MTB/RIF as a screening test for rifampicin resistance Xpert MTB/RIF sensitivity was 81% and 100% (2 studies, 20 participants; very low-certainty evidence), and specificity was 94% to 100%, (3 studies, 139 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Of the high-risks groups evaluated, Xpert MTB/RIF applied as a screening test was accurate for tuberculosis in high tuberculosis burden settings. Sensitivity and specificity were similar in people living with HIV and non-hospitalized people in high-risk groups. In people living with HIV, Xpert Ultra sensitivity was slightly higher than that of Xpert MTB/RIF and specificity similar. As there was only one study of Xpert Ultra in this analysis, results should be interpreted with caution. There were no studies that evaluated the tests in people with diabetes mellitus and other groups considered at high-risk for tuberculosis, or in the general population.

PREVALENCE OF TUBERCULOSIS, DRUG-RESISTANT TUBERCULOSIS AND HIV/TB CO-INFECTION IN ENUGU, NIGERIA

Background:

Tuberculosis (TB) remains a global public health problem, with developing countries bearing the highest burden. Nigeria is first in Africa and sixth in the world among the countries with the highest TB burden, but is among the 10 countries accounting for over 70% of the global gap in TB case detection and notification. Enugu State, Nigeria reportedly has a notification gap of almost 14,000 TB cases; a situation which must be addressed.

Materials and Methods:

A total number of 868 individuals accessing DOTS services in designated centres within the six Local Government Areas (LGAs) of Enugu North geographical zone, was recruited into the study. The participants were screened for HIV seropositivity by standard protocols, while screening for TB and drug-resistant TB were conducted by a combination of Zhiel Neelsen staining and Nucleic Acid Amplification Test (Xpert^® MTB/Rif).

Results:

Of the 868 subjects that participated in the study, 176 (20.3%) were HIV seropositive. The highest prevalence (26.7%) of HIV was recorded in Udenu LGA, while the least (13.1%) was recorded in Nsukka LGA. Overall TB prevalence was found to be 22.1% and 21.3% by sputum-smear and NAAT, respectively. Uzo Uwani LGA recorded the highest prevalence of both TB (33.3%) and TB/HIV co-infection (16.7%), but the lowest prevalence of resistant TB. Nsukka LGA had the highest prevalence of resistant TB.

Conclusion:

Enugu North geographical zone, Nigeria, has a high prevalence of both HIV and TB, including resistant TB and there is need to increase monitoring of individuals resident in this region.

Xpert MTB/RIF Ultra and Xpert MTB/RIF assays for extrapulmonary tuberculosis and rifampicin resistance in adults

BACKGROUND

Xpert MTB/RIF Ultra (Xpert Ultra) and Xpert MTB/RIF are World Health Organization (WHO)-recommended rapid nucleic acid amplification tests (NAATs) widely used for simultaneous detection of Mycobacterium tuberculosis complex and rifampicin resistance in sputum. To extend our previous review on extrapulmonary tuberculosis (Kohli 2018), we performed this update to inform updated WHO policy (WHO Consolidated Guidelines (Module 3) 2020).

OBJECTIVES

To estimate diagnostic accuracy of Xpert Ultra and Xpert MTB/RIF for extrapulmonary tuberculosis and rifampicin resistance in adults with presumptive extrapulmonary tuberculosis.

SEARCH METHODS

Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, Latin American Caribbean Health Sciences Literature, Scopus, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, the International Standard Randomized Controlled Trial Number Registry, and ProQuest, 2 August 2019 and 28 January 2020 (Xpert Ultra studies), without language restriction.

SELECTION CRITERIA

Cross-sectional and cohort studies using non-respiratory specimens. Forms of extrapulmonary tuberculosis: tuberculous meningitis and pleural, lymph node, bone or joint, genitourinary, peritoneal, pericardial, disseminated tuberculosis. Reference standards were culture and a study-defined composite reference standard (tuberculosis detection); phenotypic drug susceptibility testing and line probe assays (rifampicin resistance detection).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and applicability using QUADAS-2. For tuberculosis detection, we performed separate analyses by specimen type and reference standard using the bivariate model to estimate pooled sensitivity and specificity with 95% credible intervals (CrIs). We applied a latent class meta-analysis model to three forms of extrapulmonary tuberculosis. We assessed certainty of evidence using GRADE.

MAIN RESULTS

69 studies: 67 evaluated Xpert MTB/RIF and 11 evaluated Xpert Ultra, of which nine evaluated both tests. Most studies were conducted in China, India, South Africa, and Uganda. Overall, risk of bias was low for patient selection, index test, and flow and timing domains, and low (49%) or unclear (43%) for the reference standard domain. Applicability for the patient selection domain was unclear for most studies because we were unsure of the clinical settings. Cerebrospinal fluid Xpert Ultra (6 studies) Xpert Ultra pooled sensitivity and specificity (95% CrI) against culture were 89.4% (79.1 to 95.6) (89 participants; low-certainty evidence) and 91.2% (83.2 to 95.7) (386 participants; moderate-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 168 would be Xpert Ultra-positive: of these, 79 (47%) would not have tuberculosis (false-positives) and 832 would be Xpert Ultra-negative: of these, 11 (1%) would have tuberculosis (false-negatives). Xpert MTB/RIF (30 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 71.1% (62.8 to 79.1) (571 participants; moderate-certainty evidence) and 96.9% (95.4 to 98.0) (2824 participants; high-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 99 would be Xpert MTB/RIF-positive: of these, 28 (28%) would not have tuberculosis; and 901 would be Xpert MTB/RIF-negative: of these, 29 (3%) would have tuberculosis. Pleural fluid Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity against culture were 75.0% (58.0 to 86.4) (158 participants; very low-certainty evidence) and 87.0% (63.1 to 97.9) (240 participants; very low-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 192 would be Xpert Ultra-positive: of these, 117 (61%) would not have tuberculosis; and 808 would be Xpert Ultra-negative: of these, 25 (3%) would have tuberculosis. Xpert MTB/RIF (25 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 49.5% (39.8 to 59.9) (644 participants; low-certainty evidence) and 98.9% (97.6 to 99.7) (2421 participants; high-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 60 would be Xpert MTB/RIF-positive: of these, 10 (17%) would not have tuberculosis; and 940 would be Xpert MTB/RIF-negative: of these, 50 (5%) would have tuberculosis. Lymph node aspirate Xpert Ultra (1 study) Xpert Ultra sensitivity and specificity (95% confidence interval) against composite reference standard were 70% (51 to 85) (30 participants; very low-certainty evidence) and 100% (92 to 100) (43 participants; low-certainty evidence). Of 1000 people where 100 have lymph node tuberculosis, 70 would be Xpert Ultra-positive and 0 (0%) would not have tuberculosis; 930 would be Xpert Ultra-negative and 30 (3%) would have tuberculosis. Xpert MTB/RIF (4 studies) Xpert MTB/RIF pooled sensitivity and specificity against composite reference standard were 81.6% (61.9 to 93.3) (377 participants; low-certainty evidence) and 96.4% (91.3 to 98.6) (302 participants; low-certainty evidence). Of 1000 people where 100 have lymph node tuberculosis, 118 would be Xpert MTB/RIF-positive and 37 (31%) would not have tuberculosis; 882 would be Xpert MTB/RIF-negative and 19 (2%) would have tuberculosis. In lymph node aspirate, Xpert MTB/RIF pooled specificity against culture was 86.2% (78.0 to 92.3), lower than that against a composite reference standard. Using the latent class model, Xpert MTB/RIF pooled specificity was 99.5% (99.1 to 99.7), similar to that observed with a composite reference standard. Rifampicin resistance Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity were 100.0% (95.1 to 100.0), (24 participants; low-certainty evidence) and 100.0% (99.0 to 100.0) (105 participants; moderate-certainty evidence). Of 1000 people where 100 have rifampicin resistance, 100 would be Xpert Ultra-positive (resistant): of these, zero (0%) would not have rifampicin resistance; and 900 would be Xpert Ultra-negative (susceptible): of these, zero (0%) would have rifampicin resistance. Xpert MTB/RIF (19 studies) Xpert MTB/RIF pooled sensitivity and specificity were 96.5% (91.9 to 98.8) (148 participants; high-certainty evidence) and 99.1% (98.0 to 99.7) (822 participants; high-certainty evidence). Of 1000 people where 100 have rifampicin resistance, 105 would be Xpert MTB/RIF-positive (resistant): of these, 8 (8%) would not have rifampicin resistance; and 895 would be Xpert MTB/RIF-negative (susceptible): of these, 3 (0.3%) would have rifampicin resistance.

AUTHORS' CONCLUSIONS

Xpert Ultra and Xpert MTB/RIF may be helpful in diagnosing extrapulmonary tuberculosis. Sensitivity varies across different extrapulmonary specimens: while for most specimens specificity is high, the tests rarely yield a positive result for people without tuberculosis. For tuberculous meningitis, Xpert Ultra had higher sensitivity and lower specificity than Xpert MTB/RIF against culture. Xpert Ultra and Xpert MTB/RIF had similar sensitivity and specificity for rifampicin resistance. Future research should acknowledge the concern associated with culture as a reference standard in paucibacillary specimens and consider ways to address this limitation.

Primary Drug-Resistance Pattern and Trend in Elderly Tuberculosis Patients in Shandong, China, from 2004 to 2019

BACKGROUND

With an aging population, China is facing a huge burden of elderly patients with drug resistant tuberculosis (DR-TB), which has become a significant obstacle for the global TB control. There is still little study on DR-TB in the elderly in China so far. Thus, more research on the epidemiological characteristics and trend of primary DR-TB among the elderly will be necessary.

METHODS

A retrospective study was conducted in Shandong, China from 2004 to 2019. We collected 12,661 primary TB cases, of which 4368 elderly (≥60 years) primary TB cases were involved. Clinical characteristics including age, sex, cavity, smoking, drinking, comorbidity and drug susceptibility data were collected from 36 TB prevention and control institutions of Shandong Province. Sputum samples were collected by each surveillance site, and examined in the TB Reference Laboratory of SPCH. Descriptive statistical analysis, chi-square and linear regression were used for analyzing.

RESULTS

Among 4368 elderly patients with primary TB, the DR-TB and multi-resistant tuberculosis (MDR-TB) accounted for 17.19% and 2.29%, respectively. During 2004-2019, the proportions of MDR-TB, polydrug resistant tuberculosis (PDR-TB), rifampin (RFP)-resistance increased by 160.00%, 18.18%, 231.82%, respectively and the rate of DR-TB among elderly patients with primary cavitary TB increased by 255%. Among the elderly with primary DR-TB during 2004-2019, the proportion of male (from 85.19 to 89.06), cavity (from 7.41 to 46.88), RFP-resistance (from 3.70 to 21.88), and streptomycin (SM)-resistance (from 37.04 to 62.5) increased significantly (P<0.05). And the proportion of female (from 14.81 to 10.94), non-cavity (from 92.59 to 32.81), INH-resistance (from 66.67 to 57.81) decreased significantly (P<0.05).

CONCLUSION

Among the elderly, the proportions of MDR-TB, PDR-TB, RFP-resistance and cavitary DR-TB increased significantly. The pattern of DR-TB changed from female, non-cavity and INH-resistant groups to male, cavity, RFP or SM-resistant groups. For a better control on the elderly DR-TB in the future, we should pay more attention to male, smoking, drinking, chronic obstructive pulmonary disease (COPD) and diabetes subgroups and take targeted measures to control these subgroups.

Rifampicin-Resistant Mycobacterium tuberculosis Among Patients with Presumptive Tuberculosis in Addis Ababa, Ethiopia

Background

Drug-resistant tuberculosis remains a major public health threat complicating tuberculosis control programs globally. Data on rifampicin resistance (RR), which is a surrogate marker for multidrug resistance, are limited among Ethiopian tuberculosis patients. This study aimed to determine the magnitude of rifampicin-resistant Mycobacterium tuberculosis (RR-MTB) among presumptive tuberculosis patients attending St. Peter Tuberculosis Specialized Hospital, Addis Ababa, Ethiopia.

Patients and Methods

A retrospective cross-sectional study was conducted at St. Peter Tuberculosis Specialized Hospital from January 2016 to December 2018. After checking completeness of the necessary information, data of tuberculosis-presumptive cases who underwent Gene Xpert^® testing were collected from medical records using a data-extraction format prepared for this study purpose. Data were double entered and analyzed using SPSS version 20 statistical software.

Results

A total of 12,685 presumptive tuberculosis patients were included; of whom 54.5% were males and the mean age of the study participants was 40.3±18.7 years. Mycobacterium tuberculosis (MTB) was detected in 1714 participants (13.5%). Of these MTB cases, 169 cases (9.8%) were confirmed to have RR-MTB. Prevalence of MTB was relatively higher among males (15.1%, P=0.78); whereas RR-MTB was higher among females (10.3%, P=0.81). The incidence of MTB and RR-MTB was significantly associated with treatment history (P=0.042 and P=0.025), respectively. HIV infection has significantly associated with incidence of RR-MTB (P=0.032), but not with MTB (P˃0.05). Prevalence of MTB and RR-MTB had a declining trend through time, being 16.7% and 12.9%, 12.8% and 9.1%, and 12.2% and 7.9% in 2016, 2017 and 2018, respectively.

Conclusion

This study showed a decreasing trend of both MTB and RR-MTB from 2016 to 2018 in an MTB, MDR-MTB, and TB/HIV co-infection high-burden setting, Addis Ababa, Ethiopia. Occurrence of MTB and RR-MTB was associated with treatment history. Therefore, improvement in treatment adherence of identified cases would be helpful to prevent emergence or re-emergence of MTB and RR-MTB cases.

A pilot study on the genetic diversity of Mycobacterium tuberculosis complex strains from tuberculosis patients in the Littoral region of Cameroon

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The Xpert MTB/RIF provides a rapid MDR detection and management of TB patients.

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The Cameroon family is the predominant genotype in the Littoral region of Cameroon.

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The UgandaI sublineage is likely associated with RIF resistance in the study area.

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The mapping of the UgandaI sublineage is essential for MDR control in the country.

Background

The re-emergence of tuberculosis (TB) worldwide, compounded by multi-drug resistance (MDR) of the causative agents constitutes a major challenge to the management of the disease. Rapid diagnosis and accurate strain identification are pivotal to the control of the disease. This pilot study investigated the genetic diversity of Mycobacterium tuberculosis complex (MTBC) strains from TB patients in the Littoral region of Cameroon as well as their resistance to rifampicin (RIF).

Patients and methods

This was a cross sectional hospital-based study carried out between January and December 2017 and including 158 isolates from sputum smear positive individuals [105 (66.5%) males and 53 (33.5%) females]. Sputum samples were tested using Xpert MTB/RIF, followed by culture on Lowenstein–Jensen medium. Isolates were further subjected to molecular characterization using IS6110 typing, deletion analysis and spoligotyping.

Results

Thirteen (8.8%) of the 147 isolates with susceptibility results available were resistant to RIF. Drug resistance occurred in 5/50 (10%) female compared to 8/97 (8.2%) male (OR, 0.81; 0.25–2.62; p = 0.764), and there was no significant difference across the age ranges (p = 0.448). On the other hand, RIF resistance was associated (OR, 0.18, 95%CI, 0.05–0.69; p = 0.023) with previously treated patients [(4/14 (28.6%)] compared to new ones [9/133 (6.8%)]. The 150 identified lineages included among others 54 (36%) Cameroon, 18 (12%) UgandaI, 32 (21.3%) Haarlem, 17 (11.3%) Ghana, 9(6%) West African 1, 7(4.7%) Delhi/CAS, 4 (2.7%) LAM and 3 (2%) UgandaII. Of the 150 isolates, the major cluster was the Cameroon SIT 61, with 43(28.7%) isolates. Six (35.3%) of the 17 UgandaI sub-lineage were RIF resistant (OR, 9.58; 95%CI, 2.74–33.55, p = 0.001).

Conclusion

The cosmopolitan Littoral region presents with a wide Mycobacterium tuberculosis (MTB) strains diversity and the UgandaI sub-lineage likely associated with RIF resistance. Understanding the spread of this clade through surveillance will enhance TB control in the region.

Rifampicin-resistant Mycobacterium tuberculosis by GeneXpert MTB/RIF and Associated Factors Among Presumptive Pulmonary Tuberculosis Patients in Nepal

Background

Mycobacterium tuberculosis(MTB) remains a major public health problem worldwide, and emergence of drug-resistant TB has become a significant obstacle to effective TB control. However, the rate of MTB and rifampicin resistant-MTB (RR-MTB) in the Nepalese setting has not been studied extensively. Therefore, the present study aims to assess the rate of MTB and RR-MTB and further determine the factors associated with it.

Methods

A retrospective cross-sectional study, among national representative data of 990 consecutive presumptive TB resister of patients subjected to the GeneXpert test that presented to the tuberculosis referral hospital, was conducted over a one year period from February 2018 to January 2019. Significance for the difference for categorical data was performed by Chi-square test and factors associated with MTB and RR-MTB were assessed using binary logistic regression yielding OR with 95%CI.

Results

Of total 990 presumptive tuberculosis analyzed cases, median ages of the patients were 39±19.09 years and two-thirds of the patients were male 653 (66.0%). The estimated prevalence of MTB in presumptive TB patients was 13.8% (95%CI: 11.88%–16.16%), and risk for MTB was significantly associated with previously treated patients: OR: 10.4 (P<0.001). The estimated prevalence of RR-MTB in MTB confirmed patients was 10.2% (4.97%–15.1%). Our study confirmed no association of RR-TB with age, sex, ethnicity, geographical diversity and previous history of treatment failure (P>0.05).

Conclusion

The overall prevalence of MTB and RR-MTB was high in Nepalese study population,  and that being previously treated with anti-TB drug remained significant predictors for MTB; proactive measures are urgently needed to address the challenge of prompt diagnosis, early management and improved monitoring of treatment to limit the emergence drug-resistant MTB strains in the community.

Multitargeting Compounds: A Promising Strategy to Overcome Multi-Drug Resistant Tuberculosis

Tuberculosis is still an urgent global health problem, mainly due to the spread of multi-drug resistant M. tuberculosis strains, which lead to the need of new more efficient drugs. A strategy to overcome the problem of the resistance insurgence could be the polypharmacology approach, to develop single molecules that act on different targets. Polypharmacology could have features that make it an approach more effective than the classical polypharmacy, in which different drugs with high affinity for one target are taken together. Firstly, for a compound that has multiple targets, the probability of development of resistance should be considerably reduced. Moreover, such compounds should have higher efficacy, and could show synergic effects. Lastly, the use of a single molecule should be conceivably associated with a lower risk of side effects, and problems of drug–drug interaction. Indeed, the multitargeting approach for the development of novel antitubercular drugs have gained great interest in recent years. This review article aims to provide an overview of the most recent and promising multitargeting antitubercular drug candidates.