Association between HIV/AIDS and multi-drug resistance tuberculosis: a systematic review and meta-analysis

Epidemiology of multi-drug resistant Tuberculosis in the western region of Kenya

Multidrug-resistant tuberculosis (TB) (MDR-TB), or TB that is simultaneously resistant to both isoniazid (INH) and rifampicin (RIF), is a barrier to successful TB control and treatment. Stratified data on MDR-TB, particularly in the high-burden western Kenya region, remain unknown. This data is important to monitor the efficacy of TB control and treatment efforts. Herein, we determined the molecular epidemiology of drug-resistant TB and associated risk factors in western Kenya. This was a non-experimental, population-based, cross-sectional study conducted between January and August 2018. Morning sputum samples of individuals suspected of pulmonary TB were collected, processed, and screened for Mycobacterium tuberculosis (Mtb) and drug resistance using line probe assay (LPA) and Mycobacterium growth indicator tubes (MGIT) culture. MGIT-positive samples were cultured on brain heart infusion (BHII) agar media, and the presence of Mtb was validated using Immunochromatographic assay (ICA). Drug sensitivity was performed on MGIT and ICA-positive but BHI-negative samples. Statistical significance was set at P < 0.05. Of the 622 Mtb isolates, 536 (86.2%) were susceptible to RIF and INH. The rest, 86 (13.83%), were resistant to either drugs or both. A two-sample proportional equality test revealed that the MDR-TB prevalence in western Kenya (5%) did not vary significantly from the global MDR-TB estimate (3.9%) (P = 0.196). Men comprised the majority of susceptible and resistant TB (75.9% and 77.4%%, respectively). Also, compared with healthy individuals, the prevalence of HIV was significantly higher in MDR-TB patients (35.9% vs 5.6%). Finally, TB prevalence was highest in individuals aged 25-44 years, who accounted for 58.4% of the total TB cases. Evidently, the prevalence of MDRTB in western Kenya is high. Particular attention should be paid to men, young adults, and those with HIV, who bear the greatest burden of resistant TB. Overall, there is a need to refine TB control and treatment programs in the region to yield better outcomes.

Trends in and Risk Factors for Drug Resistance in Mycobacterium tuberculosis in HIV-Infected Patients

Trends in and risk factors for drug resistance in Mycobacterium tuberculosis (M. tuberculosis) in human immunodeficiency virus (HIV)-infected patients with active tuberculosis were analyzed. The clinical data of M. tuberculosis and HIV-coinfected patients treated at the Shanghai Public Health Clinical Center between 2010 and 2022 were collected. The diagnosis of tuberculosis was confirmed by solid or liquid culture. The phenotypic drug susceptibility test was carried out via the proportional method, and the resistance to first-line and second-line drugs was analyzed. Logistic regression analysis was performed to identify associated risk factors for drug resistance in M. tuberculosis. Of the 304 patients with a M. tuberculosis-positive culture and first-line drug susceptibility test results, 114 (37.5%) were resistant to at least one first-line anti-tuberculosis drug. Of the 93 patients with first-line and second-line drug susceptibility test results, 40 (43%) were resistant to at least one anti-tuberculosis drug, and 20 (21.5%), 27 (29.0%), 19 (20.4%), 16 (17.2%), and 14 (15.1%) were resistant to rifampicin, streptomycin, ofloxacin, levofloxacin, and moxifloxacin, respectively; 17 patients (18.3%) had multidrug-resistant tuberculosis (MDR-TB). Between 2010 and 2021, the rate of resistance to streptomycin and rifampicin ranged from 14.3% to 40.0% and from 8.0% to 26.3%, respectively, showing an increasing trend year by year. From 2016 to 2021, the rate of resistance to quinolones fluctuated between 7.7% and 27.8%, exhibiting an overall upward trend. Logistic regression analysis showed that being aged <60 years old was a risk factor for streptomycin resistance, mono-drug resistance, and any-drug resistance (RR 4.139, p = 0.023; RR 7.734, p = 0.047; RR 3.733, p = 0.009). Retreatment tuberculosis was a risk factor for resistance to rifampicin, ofloxacin, of levofloxacin (RR 2.984, p = 0.047; RR 4.517, p = 0.038; RR 6.277, p = 0.014). The drug resistance rates of M. tuberculosis to rifampicin and to quinolones in HIV/AIDS patients were high and have been increasing year by year. Age and a history of previous anti-tuberculosis treatment were the main factors associated with the development of drug resistance in HIV/AIDS patients with tuberculosis.

A systematic review and meta-analysis on the correlation between HIV infection and multidrug-resistance tuberculosis

Background

The emergence of multidrug-resistant tuberculosis (MDR-TB) in HIV-positive people poses a significant challenge to international efforts to eradicate tuberculosis (TB). Many studies found conflicting results when examining the correlation between HIV and MDR-TB. The purpose of the present investigation was to comprehensively review the literature on the association between HIV infection and MDR-TB in order to evaluate the impact of HIV on MDR-TB worldwide.

Methods

Utilizing the databases PubMed, Scopus, Google Scholar, and ScienceDirect, studies published between January 2000 and March 2023 that are eligible for meta-analysis were selected. Using the random-effects model, the aggregated odds ratio of the empirical relationship between HIV and MDR-TB was calculated, along with a confidence interval ranging from 0 to 95 %. Examining the asymmetry of the funnel plot and utilizing Egger's and Begg's test, the possibility of publication bias was investigated. The extent of heterogeneity was determined using the I2 statistics.

Results

Through a database search, we identified 1214 studies, from which we ultimately selected 15 studies involving 9667 patients. The odds ratio of 2.78 (95 % confidence interval: 1.07-7.20) between HIV/AIDS and MDR-TB indicates a significant positive correlation. Tau 2 = 3.46, chi 2 = 1440.46, df = 14, I2 = 99.0 %, z = 2.10, and p 0.05 indicate that there is substantial heterogeneity among pooled studies. Since I2 is 99 % (>50 %), a random effect model was employed. The percentage of multidrug-resistant HIV-positive patients across all included studies follows a normal distribution, as shown by a Box and whisker plot with a symmetric skewness and a mesokurtic tail and a scatter plot with a significant R2 value below 1 [R2 = 0.2476] showed the positive correlation between multidrug resistance and HIV infection.

Conclusion

HIV infection increases MDR-TB risk, and the preceding pooled analysis showed an increased risk trend. Thus, MDR-TB, especially in HIV-positive patients, requires early case detection, quality-assured bacteriology diagnosis, and an effective infection control program.

Assessment of risk factors associated with multi-drug resistant tuberculosis (MDR-TB) in Gulu regional referral hospital

Background

Multi-drug resistant tuberculosis (MDR-TB) is increasingly recognized as emerging infectious disease of public health concern. Globally, 206030 people were diagnosed with MDR-TB in 2019, representing a 10% increase from 186883people who had it in 2018. In Uganda, the prevalence of MDR among new TB cases is 4.4% and 17.7% among previously treated TB cases.

Aim

To determine the risk factors associated with MDR-TB among tuberculosis patients in Gulu regional referral hospital.

Material and Methods

A cross-sectional analytical study using both quantitative and qualitative methods of data collection and analysis was used. Data was collected from 384 TB patients using data extraction form and 6 Key informant interviews conducted. Analysis using Pearson chi-square test was run.

Results

HIV positive patients were 2.6 times more likely to be infected with MDR-TB than HIV negative patients [AOR=2.6: 95% CI 1.34- 5.85: P=0.006]. Previously treated TB patients were 2.8 times more likely to be infected with MDR-TB than newly diagnosed TB patients [AOR=2.8: 95% CI 1.33- 5.85: P=0.006]. Defaulting TB patients were 3.1 times more likely to be infected with MDR-TB than the non-defaulting TB patients [AOR=3.1].

Conclusion

There is high prevalence of drug resistance among patients attending TB treatment at the facility.

Risk factors of MDR-TB and impacts of COVID-19 pandemic on escalating of MDR-TB incidence in lower-middle-income countries: A scoping review

The coronavirus disease 2019 (COVID-19) pandemic is affecting tuberculosis (TB) treatment in many ways that might lead to increasing the prevalence of multi-drugs-resistance tuberculosis (MDR-TB), especially in lower-middle-income-countries (LMICs). This scoping review aimed to identify the risk factors of MDR-TB and to determine the impacts of the COVID-19 pandemic on MDR-TB prevalence in LMICs. This study was reported according to the preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) guideline. The relevant keywords were used to search studies in three databases (PubMed, ScienceDirect and SpringerLink) to identify the related articles. The English-written articles published from January 2012 to December 2022 that explored risk factors or causes of MDR-TB in LMICs were included. Out of 1,542 identified articles, 17 retrospective, prospective, case-control and cross-sectional studies from ten LMICs met were included in this scoping review. Twenty-one risk factors were discovered, with prior TB treatment (relapsed cases), diabetes, living area, living condition, smoking and low socioeconomic status were the main factors in developing MDR-TB during COVID-19 pandemic. The pandemic increased the MDR-TB prevalence through drug resistance transmission inside households, the distance between home and healthcare facilities and low socioeconomic status. This scoping review demonstrates how the COVID-19 pandemic has affected the rising incidence of MDR-TB in LMICs.

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.

Quantitative Assessment of a Dual Epidemic Caused by Tuberculosis and HIV in the Philippines

Tuberculosis (TB) and human immunodeficiency virus (HIV) are the two major public health emergencies in the Philippines. The country is ranked fourth worldwide in TB incidence cases despite national efforts and initiatives to mitigate the disease. Concurrently, the Philippines has the fastest-growing HIV epidemic in Asia and the Pacific region. The TB-HIV dual epidemic forms a lethal combination enhancing each other's progress, driving the deterioration of immune responses. In order to understand and describe the transmission dynamics and epidemiological patterns of the co-infection, a compartmental model for TB-HIV is developed. A class of people living with HIV (PLHIV) who did not know their HIV status is incorporated into the model. These unaware PLHIV who do not seek medical treatment are potential sources of new HIV infections that could significantly influence the disease transmission dynamics. Sensitivity analysis using the partial rank correlation coefficient is performed to assess model parameters that are influential to the output of interests. The model is calibrated using available Philippine data on TB, HIV, and TB-HIV. Parameters that are identified include TB and HIV transmission rates, progression rates from exposed to active TB, and from TB-latent with HIV to active infectious TB with HIV in the AIDS stage. Uncertainty analysis is performed to identify the degree of accuracy of the estimates. Simulations predict an alarming increase of 180% and 194% in new HIV and TB-HIV infections in 2025, respectively, relative to 2019 data. These projections underscore an ongoing health crisis in the Philippines that calls for a combined and collective effort by the government and the public to take action against the lethal combination of TB and HIV.

Strain diversity and gene mutations associated with presumptive multidrug-resistant Mycobacterium tuberculosis complex isolates in Northwest Ethiopia

OBJECTIVES

In this study, we assessed the genetic diversity and gene mutations that confer resistance to rifampicin (RIF), isoniazid (INH), fluoroquinolone (FQ), and second-line injectable (SLI) drugs in RIF-resistant (RR)/multidrug-resistant tuberculosis (MDR-TB) isolates in Northwest Ethiopia.

METHODS

Spoligotyping was used to assign isolates to TB lineages (Ls), and Hain line probe assays were used to detect resistance to RIF, INH, and FQs, and SLIs.

RESULTS

Among 130 analyzed strains, 68.5% were RR, and four major Mycobacterium tuberculosis complex lineages (L1, L3, L4, and L7) were identified with a predominance of the Euro-American L4 (72, 54.7%), while L7 genotypes were less common (3, 2.3%). Overall, the L4-T3-ETH (41, 32.0%), L3-CAS1-Delhi (29, 22.7%), and L3-CAS1-Killi (19, 14.8%) families were most common. Line probe analysis showed that among rpoB mutants, 65.2% were S450L, while 87.8% of katG mutants were S315T. Only three isolates showed mutation (c-15t) at the inhA gene, and no double mutation with katG and inhA genes was found. Six strains, two each of L1, L3, and L4, were resistant to FQs, having gyrA mutations (D94G, S91P), of which three isolates had additional resistance to SLI (rrs A1401G or C1402T mutations) including one isolate with low-level kanamycin (KAN) resistance.

CONCLUSIONS

This study showed a predominance of L4-T3-ETH, L3-CAS1-Delhi, and L3-CAS1-Killi families, with a high rate of rpoB_S450L and katG_S315T mutations and a low proportion of gyrA and rrs mutations. L7 was less frequently observed in this study. Further investigations are, therefore, needed to understand L7 and other lineages with undefined mutations.

Human Immunodeficiency Virus and Uveitis

Uveitis is one of the most common ocular complications in people living with the Human immunodeficiency virus (HIV) and can be classified into HIV-induced uveitis, co-infection related uveitis, immune recovery uveitis, and drug-induced uveitis. The introduction of antiretroviral therapy has considerably changed the incidence, diagnosis, and treatment of different types of HIV-related uveitis. Furthermore, the specific immune condition of patients infected with HIV makes diagnosing HIV-related uveitis difficult. Recent studies have focused on the growing prevalence of syphilis/tuberculosis co-infection in uveitis. Simultaneously, more studies have demonstrated that HIV can directly contribute to the incidence of uveitis. However, the detailed mechanism has not been studied. Immune recovery uveitis is diagnosed by exclusion, and recent studies have addressed the role of biomarkers in its diagnosis. This review highlights recent updates on HIV-related uveitis. Furthermore, it aims to draw the attention of infectious disease physicians and ophthalmologists to the ocular health of patients infected with HIV.

First and Second-Line Anti-Tuberculosis Drug-Resistance Patterns in Pulmonary Tuberculosis Patients in Zambia

BACKGROUND

Drug-resistant tuberculosis has continued to be a serious global health threat defined by complexity as well as higher morbidity and mortality wherever it occurs, Zambia included. However, the paucity of information on drug-susceptibility patterns of both first-line and second-line anti-tuberculosis (anti-TB) drugs, including the new and repurposed drugs used in the management of drug-resistant tuberculosis in Zambia, was the major thrust for conducting this study.

METHODS

A total of 132 bacteriologically confirmed TB isolates were collected from patients with pulmonary TB during the period from April 2020 to December 2021 in Southern and Eastern Provinces of Zambia. Drug-resistance profiles were determined according to four first-line and five second-line anti-TB drugs. Standard mycobacteriological methods were used to isolate and determine phenotypic drug susceptibility. Data on the participants' social-demographic characteristics were obtained using a pre-test checklist.

RESULTS

Overall, the prevalence of resistance to one or more anti-TB drugs was 23.5% (31/132, 95% CI: 16.5-31.6%). A total of 9.8% (13/132, 95% CI: 5.3-16.2%) of the patients had multidrug-resistant TB and 1.2% were new cases, while 25.5% had a history of being previously treated for TB. Among those with mono-resistant TB strains, isoniazid (INH) resistance was the highest at 9.8% (13/132, 95% CI: 5.3-16.2%). Two (2/31) (6.5%) XDR-TB and one (1/31) (3.2%) pre-XDR-TB cases were identified among the MDR-TB patients. Previously treated patients were 40 times more likely (OR; 40.3, 95% CI: 11.1-146.5%) to have drug-resistant TB than those who had no history of being treated for TB.

CONCLUSION

This study has established a high rate of multidrug-resistant TB and has further identified both pre-XDR- and XDR-TB. There is a need to intensify surveillance of MDR- and XDR-TB to inform future guidelines for effective treatment and monitoring.

Global trends in the incidence rates of MDR and XDR tuberculosis: Findings from the global burden of disease study 2019

Purpose: The study aimed to quantify the global trends of the incidence rates of multidrug-resistant (MDR) tuberculosis (MDR-TB) and extensively drug-resistant (XDR) tuberculosis (XDR-TB). Methods: Cases, age-standardized rates (ASRs), and incidence rates of MDR-TB and XDR-TB during 2010-2019 were obtained from the Global Burden of Disease Study 2019. The incidence trends of MDR-TB and XDR-TB were evaluated using the estimated annual percentage changes (EAPCs) in ASRs. The relationships among the ASRs of MDR-TB and XDR-TB, the MDR rate, the XDR rate, and socio-demographic index (SDI) were assessed using locally weighted regression and Pearson's correlation coefficient. Results: The global ASR of MDR-TB on average decreased by 1.36% (EAPC = -1.36, 95% confidence interval [CI] = -2.19 to -0.52) per year whereas that of XDR-TB was stable (EAPC = 0.69, 95% CI = -0.15-1.54) during 2010-2019. The incidence trends of MDR-TB in most regions and countries were decreasing, but those of XDR-TB were increasing. People aged 35-44 and 55-64 years had the highest incidence rates for MDR-TB and XDR-TB. The MDR and XDR rates both peaked in those aged 35-44 years. Areas with higher SDI tended to have lower ASRs of MDR-TB (p < 0.001, ρ = -0.43). Conclusion: The current achievements for the incidence trends of MDR-TB and XDR-TB are insufficient. More strategies and tools need to be developed to further curb MDR-TB and XDR-TB, especially in high-risk areas and age groups, and in low SDI regions.

Factors Associated of Multidrug-Resistance Tuberculosis among Minangkabau Ethnicity in Indonesia

BACKGROUND: Past tuberculosis therapy has been linked to an increased chance of developing multidrug-resistant tuberculosis (MDR-TB). Indonesia is placed 8th among the 27 nations with "high-burden" MDR-TB. AIM: The purpose of this study was to determine the risk factors associated of multidrug-resistance tuberculosis among minangkabau ethnicity in Indonesia. METHODS: The authors conducted a case control study. Data were gathered  in Dr. M Djamil General Hospital Padang, Lubuk Alung Hospital Pariaman and Primary Health Care in Padang Pariaman District from December 2019-March 2020. In this study, there were 73 cases (MDR-TB) and 219 controls (Tuberculosis) who were matched by age and sex. The sampling technique in this research was convenience sampling. Data were gathered from medical records. Bivariate and multivariate analysis were investigated using chi-square and logistic binary regression test. The data were analyzed using STATA version 14.2. Results: The risk factors for MDR-TB, cavitary pulmonary had the highest odds ratio (OR = 113.54 [95% CI 15.02-858.54]), followed by TB outside the lung (OR = 38,68 [95% CI 4.89-305.43]), nutritional status (OR = 10.92 [95% CI 5.79-20.56]), alcohol consumption (OR = 6.45 [95% CI 1.57-26.48]), working status (OR = 4.08 [95% CI 2.33-7.17]), level of education (OR = 2.79 [95% CI 1.61-4.85]), history of close contact to patients with MDR-TB and TB (OR = 2.35 [95% CI 1.30-4.22]) and diabetes mellitus (OR = 2.12 [95% CI 1.15-3.91]). Multivariate analysis found that patients with a cavitary pulmonary was significant dominant factors for MDR-TB. Conclusion: MDR-TB was predicted by previous tuberculosis therapy and cavitary pulmonary disease.

Prevalence of multidrug-resistant tuberculosis in East Africa: A systematic review and meta-analysis

Background

The rate of multidrug-resistant tuberculosis is increasing at an alarming rate throughout the world. It is becoming an emerging public health problem in East Africa. The prevalence of multidrug-resistant tuberculosis among pulmonary tuberculosis positive individuals in the region has not been thoroughly investigated.

Aim

The aim of this systematic review and meta-analysis is to estimate the pooled prevalence of multidrug-resistant tuberculosis among newly diagnosed and previously treated pulmonary tuberculosis cases in East African countries.

Methods

English published articles were systematically searched from six electronic databases: PubMed, EMBASE, Scopus, Science direct, Web of Science, and Google scholar. The pooled prevalence of multidrug-resistant tuberculosis and associated risk factors were calculated using Der Simonian and Laird’s random Effects model. Funnel plot symmetry visualization confirmed by Egger’s regression asymmetry test and Begg rank correlation methods was used to assess publication bias. A total of 16 articles published from 2007 to 2019 were included in this study. STATA 14 software was used for analysis.

Results

Out of 1025 articles identified citations, a total of 16 articles were included in final meta-analysis. The pooled prevalence of multidrug-resistant tuberculosis among newly diagnosed tuberculosis cases and previously treated tuberculosis patients was 4% (95%CI = 2–5%) and 21% (95%CI: 14–28%), respectively. Living conditions, lifestyles (smoking, alcohol use, and drug abuse), previous medical history, diabetes history, and human immunodeficiency virus infection were risk factors contributing to the higher prevalence of multidrug-resistant tuberculosis in East Africa.

Conclusion

The review found a significant prevalence of multidrug-resistant tuberculosis in the region. An early diagnosis of tuberculosis and rapid detection of drug-resistant Mycobacterium tuberculosis is a critical priority to identify patients who are not responding to the standard treatment and to avoid transmission of resistant strains. It is also very important to strengthen tuberculosis control and improve monitoring of chemotherapy.

Bedaquiline and Linezolid improve anti-TB treatment outcome in drug-resistant TB patients with HIV: A systematic review and meta-analysis

OBJECTIVES

We aimed to assess the effect of second-line anti-TB treatment and determine which drugs can achieve the greatest clinical benefit for DR-TB-HIV patients by comparing multiple chemotherapy regimens, to provide a basis for evidence-based practice.

METHODS

We searched three electronic databases (PubMed, Web of Science and Cochrane) for related English studies published since 2010. A random-effect model was used to estimate the pooled result for the treatment outcomes. Subgroup analysis based on possible factors, such as ART, baseline CD4 T-cell count, treatment regimens, and profiles of drug resistance, was also conducted to assess factors for favorable outcome. Outcomes were treatment success and mortality.

RESULTS

38 studies, 40 cohorts with 9279 patients were included. The pooled treatment success, mortality, treatment failure, and default rates were 57.5 % (95 % CI 53.1-61.9), 21 % (95 % CI 17.8-24.6), 4.8 % (95 % CI 3.5-6.5), and 10.7 % (95 % CI 8.7-13.1), respectively, in patients with DR-TB and HIV co-infection. Subgroup analysis showed that BDQ and LZD based regimen, and ≥ 2 Group A drugs were associated with a higher treatment success rate. Besides, higher CD4 T-cell count at baseline was also correlated with higher treatment success rate, too.

CONCLUSIONS

Suboptimal anti-TB outcomes underlining the need to expand the application of effective drugs and better regimen in high HIV setting. BDQ and LZD based all-oral regimen and early ART could contribute to higher treatment success, particularly among XDR-TB-HIV patients. Given that all included studies were observational, our findings emphasize the need for high-quality studies to further investigate the optimal treatment regimen for DR-TB-HIV.

Distribución y frecuencia de potenciales mutaciones asociadas con la resistencia a rifampicina en el gen rpoB de Mycobacterium tuberculosis detectadas mediante un método molecular automatizado

Introducción. La tuberculosis continúa siendo un problema de salud pública agravado por la resistencia de Mycobacterium tuberculosis a los fármacos. Más del 95% de cepas de M. tuberculosis resistentes a rifampicina (RIF) poseen mutaciones en una región del gen rpoB. Xpert® MTB/RIF es un sistema de biología molecular que, mediante 5 sondas (A, B, C, D, E) que conforman las secuencias del gen rpoB, permite identificar mutaciones en la región determinante de resistencia a la RIF de este gen. Objetivo. Describir la distribución y frecuencia de potenciales mutaciones asociadas con la resistencia a RIF en el gen rpoB de M. tuberculosis detectadas en muestras pulmonares y extrapulmonares usando el método Xpert® MTB/RIF. Materiales y métodos. Estudio retrospectivo. Se analizaron 66 muestras positivas para M. tuberculosis resistente a RIF procesadas por el sistema GeneXpert MTB/RIF entre enero de 2011 y julio de 2019 en un hospital universitario de Medellín, Colombia. De acuerdo con el software Dx System del instrumento GenXpert, se determinó que había una potencial mutación y resistencia a RIF, si la sondas no se unían a su secuencia complementaria natural o si se presentaba un atraso en la unión (delta CT >4) en relación con las otras sondas por presencia de una secuencia anormal. Los datos se analizaron mediante estadística descriptiva. Resultados. De las 66 muestras (48 pulmonares y 18 extrapulmonares), el 63.64% eran de hombres y la edad media de los participantes fue 39.60 ± 17.69 años. La frecuencia y distribución de mutaciones fue la siguiente: sonda E: 38 mutaciones (57.58%); B: 16 (24.24%), D: 8 (12.12%); A: 3 (4.54%) y D&E: 1 (1.52%). No se detectó ninguna mutación en la sonda C. Conclusiones. Las mutaciones asociadas a la resistencia a RIF en el gen rpoB de M. tuberculosis detectadas por el método Xpert® MTB/RIF se encontraron principalmente en la sonda E (codones 529–533). Por el contrario, en la sonda C no se no se detectó ninguna mutación.

Molecular surveillance of tuberculosis-causing mycobacteria in wastewater

The surveillance of tuberculosis infections has largely depended on clinical diagnostics and hospitalization data. The advancement in molecular methods creates an opportunity for the adoption of alternative surveillance systems, such as wastewater-based epidemiology. This study presents the use of conventional and advanced polymerase chain reaction techniques (droplet digital PCR) to determine the occurrence and concentration of total mycobacteria and members of the Mycobacterium tuberculosis complex (MTBC) in treated and untreated wastewater. Wastewater samples were taken from three wastewater treatment plants (WWTPs) in the city of Durban, South Africa, known for a high burden of TB/MDR-TB due to HIV infections. All untreated wastewater samples contained total mycobacteria and MTBC at varying percentages per WWTP studied. Other members of the MTBC related to tuberculosis infection in animals, M. bovis and M. caprae were also detected. The highest median concentration detected in untreated wastewater was up to 4.9 (±0.2) Log10 copies/ml for total mycobacteria, 4.0 (±0.85) Log10 copies/ml for MTBC, 3.9 (±0.54) Log10 copies/ml for M. tuberculosis, 2.7 (±0.42) Log10 copies/ml for M. africanum, 4.0 (±0.29) Log10 copies/ml for M. bovis and 4.5 (±0.52) Log10 copies/ml for M. caprae. Lower concentrations were detected in the treated wastewater, with a statistically significant difference (P-value ≤ 0.05) in concentrations observed. The log reduction achieved for these bacteria in the respective WWTPs was not statistically different, indicating that the treatment configuration did not have an impact on their removal. The detection of M. africanum in wastewater from South Africa shows that it is possible that some of the TB infections in the community could be caused by this mycobacterium. This study, therefore, highlights the potential of wastewater-based epidemiology for monitoring tuberculosis infections.

The source and fate of Mycobacterium tuberculosis complex in wastewater and possible routes of transmission

BACKGROUND

The Mycobacterium tuberculosis complex (MTBC) consists of causative agents of both human and animal tuberculosis and is responsible for over 10 million annual infections globally. Infections occur mainly through airborne transmission, however, there are possible indirect transmissions through a faecal-oral route which is poorly reported. This faecal-oral transmission could be through the occurrence of the microbe in environments such as wastewater. This manuscript, therefore, reviews the source and fate of MTBC in the wastewater environment, including the current methods in use and the possible risks of infections.

RESULTS

The reviewed literature indicates that about 20% of patients with pulmonary TB may have extra-pulmonary manifestations such as GITB, resulting in shedding in feaces and urine. This could potentially be the reason for the detection of MTBC in wastewater. MTBC concentrations of up to 5.5 × 105 (±3.9 × 105) copies/L of untreated wastewater have been reported. Studies have indicated that wastewater may provide these bacteria with the required nutrients for their growth and could potentially result in environmental transmission. However, 98.6 (± 2.7) %, removal during wastewater treatment, through physical-chemical decantation (primary treatment) and biofiltration (secondary treatment) has been reported. Despite these reports, several studies observed the presence of MTBC in treated wastewater via both culture-dependent and molecular techniques.

CONCLUSION

The detection of viable MTBC cells in either treated or untreated wastewater, highlights the potential risks of infection for wastewater workers and communities close to these wastewater treatment plants. The generation of aerosols during wastewater treatment could be the main route of transmission. Additionally, direct exposure to the wastewater containing MTBC could potentially contribute to indirect transmissions which may lead to pulmonary or extra-pulmonary infections. This calls for the implementation of risk reduction measures aimed at protecting the exposed populations.

Rifampicin resistance and mortality in patients hospitalised with HIV-associated tuberculosis

Background

Patients with HIV and drug-resistant tuberculosis (TB) are at high risk of death.

Objectives

We investigated the association between rifampicin-resistant TB (RR-TB) and mortality in a cohort of patients who were admitted to hospital at the time of TB diagnosis.

Method

Adults hospitalised at Khayelitsha Hospital and diagnosed with HIV-associated TB during admission, were enrolled between 2013 and 2016. Clinical, biochemical and microbiological data were prospectively collected and participants were followed up for 12 weeks.

Results

Participants with microbiologically confirmed TB (n = 482) were enrolled a median of two days (interquartile range [IQR]: 1-3 days) following admission. Fifty-three participants (11.0%) had RR-TB. Participants with rifampicin-susceptible TB (RS-TB) received appropriate treatment a median of one day (IQR: 1-2 days) following enrolment compared to three days (IQR: 1-9 days) in participants with RR-TB. Eight participants with RS-TB (1.9%) and six participants with RR-TB (11.3%) died prior to the initiation of appropriate treatment. Mortality at 12 weeks was 87/429 (20.3%) in the RS-TB group and 21/53 (39.6%) in the RR-TB group. RR-TB was a significant predictor of 12-week mortality (hazard ratio: 1.88; 95% confidence interval: 1.07-3.29; P = 0.03).

Conclusion

Mortality at 12 weeks in participants with RR-TB was high compared to participants with RS-TB. Delays in the initiation of appropriate treatment and poorer regimen efficacy are proposed as contributors to higher mortality in hospitalised patients with HIV and RR-TB.

Design and synthesis of leucylaniline derivatives as leucyl-tRNA synthetase inhibitors

By simulating the structure of Leu-AMP, 26 leu-arylamine derivatives were designed and synthesized as leucyl-tRNA Synthetase inhibitors; compounds 19 and 24 showed good anti-tuberculosis activity.

Incidence and predictors of mortality among persons receiving second-line tuberculosis treatment in sub-Saharan Africa: A meta-analysis of 43 cohort studies

BACKGROUND

Drug resistance remains from among the most feared public health threats that commonly challenges tuberculosis treatment success. Since 2010, there have been rapid evolution and advances to second-line anti-tuberculosis treatments (SLD). However, evidence on impacts of these advances on incidence of mortality are scarce and conflicting. Estimating the number of people died from any cause during the follow-up period of SLD as the incidence proportion of all-cause mortality is the most informative way of appraising the drug-resistant tuberculosis treatment outcome. We thus aimed to estimate the pooled incidence of mortality and its predictors among persons receiving the SLD in sub-Saharan Africa.

METHODS

We systematically identified relevant studies published between January, 2010 and March, 2020, by searching PubMed/MEDLINE, EMBASE, SCOPUS, Cochrane library, Google scholar, and Health Technology Assessment. Eligible English-language publications reported on death and/or its predictors among persons receiving SLD, but those publications that reported death among persons treated for extensively drug-resistant tuberculosis were excluded. Study features, patients' clinical characteristics, and incidence and/or predictors of mortality were extracted and pooled for effect sizes employing a random-effects model. The pooled incidence of mortality was estimated as percentage rate while risks of the individual predictors were appraised based on their independent associations with the mortality outcome.

RESULTS

A total of 43 studies were reviewed that revealed 31,525 patients and 4,976 deaths. The pooled incidence of mortality was 17% (95% CI: 15%-18%; I2 = 91.40; P = 0.00). The studies used varied models in identifying predictors of mortality. They found diagnoses of clinical conditions (RR: 2.36; 95% CI: 1.82-3.05); excessive substance use (RR: 2.56; 95% CI: 1.78-3.67); HIV and other comorbidities (RR: 1.96; 95% CI: 1.65-2.32); resistance to SLD (RR: 1.75; 95% CI: 1.37-2.23); and male sex (RR: 1.82; 95% CI: 1.35-2.44) as consistent predictors of the mortality. Few individual studies also reported an increased incidence of mortality among persons initiated with the SLD after a month delay (RR: 1.59; 95% CI: 0.98-2.60) and those persons with history of tuberculosis (RR: 1.21; 95% CI: 1.12-1.32).

CONCLUSIONS

We found about one in six persons who received SLD in sub-Saharan Africa had died in the last decade. This incidence of mortality among the drug-resistant tuberculosis patients in the sub-Saharan Africa mirrors the global average. Nevertheless, it was considerably high among the patients who had comorbidities; who were diagnosed with other clinical conditions; who had resistance to SLD; who were males and substance users. Therefore, modified measures involving shorter SLD regimens fortified with newer or repurposed drugs, differentiated care approaches, and support of substance use rehabilitation programs can help improve the treatment outcome of persons with the drug-resistant tuberculosis.

TRIAL REGISTRATION NUMBER

CRD42020160473; PROSPERO.

Potential contribution of HIV during first-line tuberculosis treatment to subsequent rifampicin-monoresistant tuberculosis and acquired tuberculosis drug resistance in South Africa: a retrospective molecular epidemiology study

Background

South Africa has a high burden of rifampicin-resistant tuberculosis (including multidrug-resistant [MDR] tuberculosis), with increasing rifampicin-monoresistant (RMR) tuberculosis over time. Resistance acquisition during first-line tuberculosis treatment could be a key contributor to this burden, and HIV might increase the risk of acquiring rifampicin resistance. We assessed whether HIV during previous treatment was associated with RMR tuberculosis and resistance acquisition among a retrospective cohort of patients with MDR or rifampicin-resistant tuberculosis.

Methods

In this retrospective cohort study, we included all patients routinely diagnosed with MDR or rifampicin-resistant tuberculosis in Khayelitsha, Cape Town, South Africa, between Jan 1, 2008, and Dec 31, 2017. Patient-level data were obtained from a prospective database, complemented by data on previous tuberculosis treatment and HIV from a provincial health data exchange. Stored MDR or rifampicin-resistant tuberculosis isolates from patients underwent whole-genome sequencing (WGS). WGS data were used to infer resistance acquisition versus transmission, by identifying genomically unique isolates (single nucleotide polymorphism threshold of five). Logistic regression analyses were used to assess factors associated with RMR tuberculosis and genomic uniqueness.

Findings

The cohort included 2041 patients diagnosed with MDR or rifampicin-resistant tuberculosis between Jan 1, 2008, and Dec 31, 2017; of those, 463 (22·7%) with RMR tuberculosis and 1354 (66·3%) with previous tuberculosis treatment. In previously treated patients, HIV positivity during previous tuberculosis treatment versus HIV negativity (adjusted odds ratio [OR] 2·07, 95% CI 1·35–3·18), and three or more previous tuberculosis treatment episodes versus one (1·96, 1·21–3·17) were associated with RMR tuberculosis. WGS data showing MDR or rifampicin-resistant tuberculosis were available for 1169 patients; 360 (30·8%) isolates were identified as unique. In previously treated patients, RMR tuberculosis versus MDR tuberculosis (adjusted OR 4·96, 3·40–7·23), HIV positivity during previous tuberculosis treatment (1·71, 1·03–2·84), and diagnosis in 2013–17 (1·42, 1·02–1·99) versus 2008–12, were associated with uniqueness. In previously treated patients with RMR tuberculosis, HIV positivity during previous treatment (adjusted OR 5·13, 1·61–16·32) was associated with uniqueness as was female sex (2·50 [1·18–5·26]).

Interpretation

These data suggest that HIV contributes to rifampicin-resistance acquisition during first-line tuberculosis treatment and that this might be driving increasing RMR tuberculosis over time. Large-scale prospective cohort studies are required to further quantify this risk.

Funding

Swiss National Science Foundation, South African National Research Foundation, and Wellcome Trust.

New management approaches to tuberculosis in people living with HIV

PURPOSE OF REVIEW

People living with HIV (PLWH) are commonly coinfected with Mycobacterium tuberculosis, particularly in high-transmission resource-limited regions. Despite expanded access to antiretroviral therapy and tuberculosis (TB) treatment, TB remains the leading cause of death among PLWH. This review discusses recent advances in the management of TB in PLWH and examines emerging therapeutic approaches to improve outcomes of HIV-associated TB.

RECENT FINDINGS

Three recent key developments have transformed the management of HIV-associated TB. First, the scaling-up of rapid point-of-care urine-based tests for screening and diagnosis of TB in PLWH has facilitated early case detection and treatment. Second, increasing the availability of potent new and repurposed drugs to treat drug-resistant TB has generated optimism about the treatment and outcome of multidrug-resistant and extensively drug-resistant TB. Third, expanded access to the integrase inhibitor dolutegravir to treat HIV in resource-limited regions has simplified the management of TB/HIV coinfected patients and minimized serious adverse events.

SUMMARY

While it is unequivocal that substantial progress has been made in early detection and treatment of HIV-associated TB, significant therapeutic challenges persist. To optimize the management and outcomes of TB in HIV, therapeutic approaches that target the pathogen as well as enhance the host response should be explored.

Xpert Mycobacterium tuberculosis/Rifampicin-Detected Rifampicin Resistance is a Suboptimal Surrogate for Multidrug-resistant Tuberculosis in Eastern Democratic Republic of the Congo: Diagnostic and Clinical Implications

BACKGROUND

Rifampicin (RIF) resistance is highly correlated with isoniazid (INH) resistance and used as proxy for multidrug-resistant tuberculosis (MDR-TB). Using MTBDRplus as a comparator, we evaluated the predictive value of Xpert MTB/RIF (Xpert)-detected RIF resistance for MDR-TB in eastern Democratic Republic of the Congo (DRC).

METHODS

We conducted a cross-sectional study involving data from new or retreatment pulmonary adult TB cases evaluated between July 2013 and December 2016. Separate, paired sputa for smear microscopy and MTBDRplus were collected. Xpert testing was performed subject to the availability of Xpert cartridges on sample remnants after microscopy.

RESULTS

Among 353 patients, 193 (54.7%) were previously treated and 224 (63.5%) were MTBDRplus TB positive. Of the 224, 43 (19.2%) were RIF monoresistant, 11 (4.9%) were INH monoresistant, 53 (23.7%) had MDR-TB, and 117 (52.2%) were RIF and INH susceptible. Overall, among the 96 samples detected by MTBDRplus as RIF resistant, 53 (55.2%) had MDR-TB. Xpert testing was performed in 179 (50.7%) specimens; among these, 163 (91.1%) were TB positive and 73 (44.8%) RIF resistant. Only 45/73 (61.6%) Xpert-identified RIF-resistant isolates had concomitant MTBDRplus-detected INH resistance. Xpert had a sensitivity of 100.0% (95% CI, 92.1-100.0) for detecting RIF resistance but a positive-predictive value of only 61.6% (95% CI, 49.5-72.8) for MDR-TB. The most frequent mutations associated with RIF and INH resistance were S531L and S315T1, respectively.

CONCLUSIONS

In this high-risk MDR-TB study population, Xpert had low positive-predictive value for the presence of MDR-TB. Comprehensive resistance testing for both INH and RIF should be performed in this setting.

Mortality from drug-resistant tuberculosis in high-burden countries comparing routine drug susceptibility testing with whole-genome sequencing: a multicentre cohort study

Background

Drug resistance threatens global tuberculosis control. We aimed to examine mortality in patients with tuberculosis from high-burden countries, according to concordance or discordance of results from drug susceptibility testing done locally and whole-genome sequencing (WGS).

Methods

In this multicentre cohort study, we collected pulmonary Mycobacterium tuberculosis isolates and clinical data from individuals with tuberculosis from antiretroviral therapy programmes and tuberculosis clinics in Côte d’Ivoire, Democratic Republic of the Congo, Kenya, Nigeria, Peru, South Africa, and Thailand, stratified by HIV status and drug resistance. Sites tested drug susceptibility using routinely available methods. WGS was done on Illumina HiSeq 2500 in the USA and Switzerland, and TBprofiler was used to analyse the genomes. We included individuals aged 16 years or older with pulmonary tuberculosis (bacteriologically confirmed or clinically diagnosed). We analysed mortality in multivariable logistic regression models adjusted for sex, age, HIV status, history of tuberculosis, and sputum positivity.

Findings

Between Sept 1, 2014, and July 4, 2016, of 634 patients included in our previous analysis, we included 582 patients with tuberculosis (median age 33 years [IQR 27–43], 225 [39%] women, and 247 [42%] HIV-positive). Based on WGS, 339 (58%) isolates were pan-susceptible, 35 (6%) monoresistant, 146 (25%) multidrug-resistant, and 24 (4%) pre-extensively drug-resistant (pre-XDR) or XDR. The analysis of mortality was based on 530 patients; 63 (12%) died and 77 (15%) patients received inappropriate treatment. Mortality ranged from 6% (18 of 310) in patients with pan-susceptible tuberculosis to 39% (nine of 23) in patients with pre-XDR or XDR tuberculosis. The adjusted odds ratio for mortality was 4·92 (95% CI 2·47–9·78) among undertreated patients, compared with appropriately treated patients.

Interpretation

In seven countries with a high burden of tuberculosis, we observed discrepancies between drug resistance patterns obtained locally and WGS. The underdiagnosis of drug resistance resulted in inappropriate treatment and higher mortality. WGS can provide accurate and detailed drug resistance information required to improve the outcomes of drug-resistant tuberculosis in high-burden settings. Our results support WHO’s call for point-of-care tests based on WGS.

Funding

National Institutes of Allergy and Infectious Diseases, Swiss National Science Foundation, and Swiss National Center for Mycobacteria.

Khat Chewing and Clinical Conditions Determine the Epidemiology of Primary Drug Resistance Tuberculosis in Amhara Region of Ethiopia: A Multicenter Study

BACKGROUND

Rifampicin and/or multidrug-resistant tuberculosis (RR/MDR-TB) remains an uncontrolled public health emergency that has been synergized by the recently increased person-to-person transmission in the community as primary RR/MDR-TB, which is defined as RR/MDR-TB in new TB patients with no prior exposure to anti-TB treatment for more than one month. This study aimed to measure the prevalence and associated factors of primary drug-resistance among drug-resistant tuberculosis patients, as evidenced by the Amhara region treatment initiating centers.

METHODS

An institutional-based multicenter cross-sectional study was conducted from September 2010 to December 2017, among 580 RR/MDR-TB patients on the second-line anti-TB drug in the Amhara regional state. Data were collected from patient charts and registration books using a standardized data abstraction sheet. The data were entered using Epi-data 4.2.0.0 and transferred to Stata 14 software for further data management and analysis. A bivariable and multivariable binary logistic model was run subsequently, and finally, a p-value of less than 0.05 with a 95% confidence interval (CI) was used to declare the significance of the explanatory variable.

RESULTS

The magnitude of primary drug resistance among drug-resistant tuberculosis patients was 15.69% (95% CI: 12.94, 18.89). Alcohol drinking (adjusted odds ratio [AOR] = 0.31, 95% CI: 0.12-0.82), khat chewing (AOR = 4.43; 95% CI: 1.67-11.76), ambulatory and bedridden functional status (AOR = 0.43; 95% CI: 0.24-0.76) and (AOR = 0.41; 95% CI: 0.19-0.91), respectively, positive sputum smear result (AOR = 0.48; 95% CI: 0.26-0.90), and HIV coinfection (AOR= 2.31; 95% CI: 1.31-4.06) remained statistically significant associated factors of primary RR/MDR-TB.

CONCLUSION

Primary drug resistance is a public health problem in the study setting. Different behavioral and clinical conditions were significant factors of primary drug-resistant development. Mitigation strategies targeted on the patient's clinical condition, substance-related behaviors, and universal DST coverage might be very important for early detection and treatment of RR/MDR-TB to prevent community-level transmission.

The pattern of comorbidity and its prevalence among drug-resistant tuberculosis patients at treatment initiation in Lagos, Nigeria

BACKGROUND

Multimorbidity is increasingly being recognized as a serious public health concern in the control of both drug-susceptible and drug-resistant tuberculosis (DR-TB). This study assessed the pattern of comorbidities and their prevalence in DR-TB patients at treatment initiation in Lagos, Nigeria.

METHODS

A cross-sectional study was conducted. The baseline laboratory records (human immunodeficiency virus [HIV] status, fasting blood sugar, audiometry, thyroid function tests, serum electrolyte, haemoglobin level and pregnancy test) of DR-TB patients initiated on treatment in Lagos, Nigeria between 1 August 2014 and 31 March 2017 were reviewed.

RESULTS

A total of 565 DR-TB patients' laboratory records were reviewed, of which 397 (70.3%) had comorbidities. The proportion with one, two, three and four comorbidities was 60.2%, 29.7%, 8.1% and 2.0%, respectively. Anaemia was the most common (48.1%) comorbid condition, while anaemia and hypokalaemia (7.3%), anaemia and hypothyroidism (6.5%) and anaemia and HIV (5%) were most common among patients with more than one comorbid condition. DR-TB patients with comorbidity were significantly older (34.8±12.3 y) than those without comorbidity (32.0±12.8 y) (p=0.038). Of the 176 females in the reproductive age group, 8 (4.5%) were pregnant at baseline.

CONCLUSIONS

The prevalence of comorbidity among DR-TB patients was high. There is a need for the national TB program to expand its DR-TB council of experts and also integrate reproductive health services into DR-TB management in Nigeria.

Complexities in the treatment of coinfection with HIV, hepatitis B, hepatitis C, and tuberculosis

HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV) are commonly encountered blood-borne infectious microorganisms. Infection with these viruses typically requires long-lasting drug therapy. Coinfections, especially with tuberculosis, pose a challenge to the creation of a regimen with adequate efficacy and minimal drug-drug interactions and adverse effects. We present the case of a young man with a history of intravenous drug misuse who was diagnosed with disseminated tuberculosis and with a triple infection with HBV, HCV, and HIV. The treatment for tuberculosis was initiated first, followed 2 months later by antiretrovirals that were effective against both HIV and HBV. After 9 months of antitubercular therapy, HCV was successfully treated with 12 weeks of oral direct-acting antivirals. We describe the challenges faced in formulating a therapeutic plan for such patients and discuss the various drug interactions that can arise between antitubercular drugs, antiretrovirals, anti-HBV drugs, and direct-acting antivirals against HCV.

Epidemiological profile of patients with rifampicin-resistant tuberculosis: an analysis of the Uganda National Tuberculosis Reference Laboratory Surveillance Data, 2014-2018

BACKGROUND

Drug-resistant tuberculosis (DR-TB), including rifampicin-resistant tuberculosis (RR-TB) and multidrug-resistant tuberculosis (MDR-TB, or RR-TB with additional isoniazid resistance), presents challenges to TB control. In Uganda, the GeneXpert test provides point-of-care testing for TB and rifampicin resistance. Patients identified with RR-TB receive culture-based drug susceptibility testing (DST) to identify additional resistance, if any. There are few data on the epidemiological profiles of current DR-TB patients in Uganda. We described patients with RR-TB in Uganda and assessed the trends of RR-TB to inform TB control interventions.

METHODS

We identified patients with RR-TB whose samples were referred for culture and DST during 2014-2018 from routinely-generated laboratory surveillance data at the Uganda National Tuberculosis Reference Laboratory. Data on patient demographics and drug sensitivity profile of Mycobacterium tuberculosis isolates were abstracted. Population data were obtained from the Uganda Bureau of Statistics to calculate incidence. Descriptive epidemiology was performed, and logistic regression used to assess trends.

RESULTS

We identified 1474 patients whose mean age was 36 ± 17 years. Overall incidence was 3.8/100,000 population. Males were more affected by RR-TB than females (4.9 vs. 2.7/100,000, p ≤ 0.01). Geographically, Northern Uganda was the most affected region (IR = 6.9/100,000) followed by the Central region (IR = 5.01/100,000). The overall population incidence of RR-TB increased by 20% over the evaluation period (OR = 1.2; 95% CI 1.15-1.23); RR-TB in new TB cases increased by 35% (OR = 1.35; 95% CI 1.3-1.4) and by 7% in previously-treated cases (OR = 1.07; 95% CI 1.0-1.1). Of the 1474 patients with RR-TB, 923 (63%) were culture-positive of whom 670 (72%) had full DST available. Based on the DST results, 522/670 (78%) had MDR-TB.

CONCLUSION

Between 2014 and 2018, the incidence of RR-TB increased especially among newly-diagnosed TB patients. We recommend intensified efforts and screening for early diagnosis especially among previously treated patients. Mechanisms should be in put to ensure that all patients with RR-TB obtain DST.

Prevalence of rifampicin resistance tuberculosis among HIV/TB coinfected patients in Benue State, Nigeria

Introduction

the emergence of HIV/TB co-infection has changed the global health landscape globally, particularly in sub-Saharan Africa and Asia with a high prevalence rate. It has further worsened and compound patient diagnosis, treatment/management approach and infection control. Rifampicin resistance TB (RR-TB) is a good indicator of treatment failure and infection control in the community. This study determines the prevalence of RR-TB among HIV/TB coinfected patients in Benue State, Nigeria.

Methods

the case-control study was carried out at Federal Medical Centre, Makurdi and General Hospital, Otupko, between January 2017 and February 2018. One thousand and ten suspected tuberculosis and HIV patients were enrolled in the study, diagnosed according to WHO guidelines. Sputum samples were collected and then analyzed by acid-fast bacilli smear test and GeneXpert MTB/RIF assay.

Results

overall prevalence of tuberculosis by acid-fast test was 74 (7.3%), 171 (16.93%) by GeneXpert assay and 2.18% by RR-TB test respectively. Significant difference was observed between the detection technique and demographic variables, high prevalence among urban patient compared to rural (8.85%vs 5.40%; X²= 4.38; P = 0.036) and ethnic background of the patients (X²= 23.21; P = 0.000) by acid fast test. With GeneXpert, high prevalence recorded among patient within age-group15-45years (X²= 8.01; P = 0.046) and ethnic group (X²= 6.30; P = 0.044). The occurrence of HIV/TB co-infection was less associated with Idoma ethnic group (COR; 0.440; 95% C.I; 0.246 - 0.786).

Conclusion

the relatively high prevalence of HIV/TB co-infection and RR-TB is a tremendous public health threat, considering society's attendant implication. Further surveillance studies are needed to evaluate the situation in Benue State better.

HIV infection and multidrug resistant tuberculosis: a systematic review and meta-analysis

BACKGROUND

Multidrug-resistant tuberculosis (MDR-TB) in HIV infected individuals is a serious threat to global efforts to combat tuberculosis. Inconsistent findings on the association between HIV infection and MDR-TB were present in many studies. We aimed to review existing data on the relationship between HIV infection and MDR-TB systematically to assess the contribution of HIV on MDR-TB worldwide. We also investigated the patterns of MDR-TB by age, country-wise income, study designs, and global regions.

METHODS

We utilized PubMed, Google Scholar, and ScienceDirect databases to select eligible studies for meta-analysis that were published between January 12,010, and July 30, 2020. The random-effects model was used to obtain the pooled odds ratio of the crude association between HIV and MDR-TB with a 95% confidence interval. We investigated the potential publication-bias by checking funnel plot asymmetry and using the Egger's test. Moreover, we assessed the heterogeneity using the I² statistic. Sensitivity analysis was performed based on sample size and adjustment factors. The protocol was registered with PROSPERO-CRD42019132752.

RESULTS

We identified 1603 studies through a database search, and after subsequent eliminations we selected 54 studies including 430,534 TB patients. The pooled odds of MDR-TB was 1.42 times higher in HIV-positive patients than HIV-negative patients (OR=1.42,CI=1.17-1.71, I²=75.8%). Subgroup analysis revealed that the estimated pooled odds for South-East Asian countries was 1.86, which is the highest in WHO regions (OR=1.86,CI=1.30-2.67, I²=0.00%), followed by Europe and Africa. The effect estimate was found to be higher for primary MDR-TB (OR=2.76,CI=1.70-4.46, I²=0.00%). There was also a trend towards increased odds of MDR-TB for HIV patients older than 40 years (OR=1.56,CI=1.17-2.06). The association was found to be significant in high-burden TB countries (OR=1.75, CI=1.39-2.19) and in high-income countries (OR=1.55, CI=1.06-2.27).

CONCLUSION

Such findings indicate that HIV infection raises the risk of MDR-TB, and after contrasting it with the results of the earlier pooled study, it appeared to be an upward risk trend. Moreover, we found that the risk is the highest in the South-East Asian region. A balanced allocation of resources is needed to halt both primary and secondary MDR-TB, particularly in HIV infected people with 40 years of age and older.

Mechanochemical Synthesis and Physicochemical Characterization of Isoniazid and Pyrazinamide Co-crystals With Glutaric Acid

The present work reports two novel pharmaceutical co-crystals; 2:1 isoniazid-glutaric acid (INHGA) and 2:1 pyrazinamide-glutaric acid (PGA). Isoniazid and pyrazinamide are key first-line drugs used for the treatment of tuberculosis. The co-crystals were produced via solid-state and solvent assisted grinding methods. Thermal characteristics of the samples were obtained using the differential scanning calorimetry, hot stage microscopy, and thermogravimetric analyses. The morphology of the powder samples by scanning electron microscopy, structural analysis by Fourier transform infrared spectroscopy and powder X-rays diffraction ensured co-crystal formation. Thermal analyses confirmed the co-crystals with new melting transitions ranging between their respective starting materials. Unique morphologies of the co-crystal particles were clear in SEM micrographs. The formation of intermolecular interactions with the co-crystal former was confirmed by the FT-IR spectral band shifting and was supported by distinct PXRD patterns of co-crystals thereby authenticating the successful co-crystal formation. In vitro solubility evaluation of the synthesized co-crystals by HPLC suggested a remarkable increase in solubility of both INH and PZA in their respective co-crystals.

Characterization of Mycobacterium tuberculosis genotypes and their correlation to multidrug resistance in Lusaka, Zambia

OBJECTIVES

The burden of multidrug-resistant tuberculosis (MDR-TB) has been reported to be increasing in Zambia. The reasons for the increase are still unclear. This study determined the diversity of Mycobacterium tuberculosis genotypes among isolates in Lusaka, the capital city, and investigated their association with MDR-TB.

METHODS

Spoligotyping, large sequence polymorphism (LSP) analysis, and sequencing of MDR associated genes were performed on a total of 274 M. tuberculosis clinical isolates stored at the University Teaching Hospital from 2013 to 2017. Of these, 134 were MDR-TB while 126 were pan-susceptible.

RESULTS

Spoligotyping showed the LAM family as the most predominant genotype (149/274, 54.4%) followed by the CAS family (44/274, 16.1%), T family (39/274, 14.2%), and minor proportions of X, S, Harleem, EAI and Beijing spoligofamilies were identified. Three M. bovis isolates were also observed. Among those, CAS1-Kili (SIT 21) and LAM1 (SIT 20) subfamilies showed a propensity for MDR-TB with p = 0.0001 and p = 0.001, respectively.

CONCLUSIONS

This phenomenon might explain the future increase in the MDR-TB burden caused by specific lineages in Zambia. Therefore, it is recommended that the National TB control program in the country complements conventional control strategies with molecular analysis for monitoring and surveillance of MDR-TB epidemiology.

Multidrug-resistant tuberculosis in children and adolescents: current strategies for prevention and treatment

INTRODUCTION

An estimated 30,000 children develop multidrug-resistant (MDR) tuberculosis (TB) each year, with only a small proportion diagnosed and treated. This field has historically been neglected due to the perception that children with MDR-TB are challenging to diagnose and treat. Diagnostic and therapeutic developments in adults have improved pediatric management, yet further pediatric-specific research and wider implementation of evidence-based practices are required.

AREAS COVERED

This review combines the most recent data with expert opinion to highlight best practice in the evaluation, diagnosis, treatment, and support of children and adolescents with MDR-TB disease. A literature search of PubMed was carried out on topics related to MDR-TB in children. This review provides practical advice on MDR-TB prevention and gives updates on new regimens and novel treatments. The review also addresses host-directed therapy, comorbid conditions, special populations, psychosocial support, and post-TB morbidity, as well as identifying outstanding research questions.

EXPERT OPINION

Increased availability of molecular diagnostics has the potential to aid with the diagnosis of MDR-TB in children. Shorter MDR-TB disease treatment regimens have made therapy safer and shorter and further developments with novel agents and repurposed drugs should lead to additional improvements. The evidence base for MDR-TB preventive therapy is increasing.

Using Bayesian spatial models to map and to identify geographical hotspots of multidrug-resistant tuberculosis in Portugal between 2000 and 2016

Multidrug-resistant tuberculosis (MDR-TB) is a major threat to the eradication of tuberculosis. TB control strategies need to be adapted to the necessities of different countries and adjusted in high-risk areas. In this study, we analysed the spatial distribution of the MDR- and non-MDR-TB cases across municipalities in Continental Portugal between 2000 and 2016. We used Bayesian spatial models to estimate age-standardized notification rates and standardized notification ratios in each area, and to delimitate high- and low-risk areas, those whose standardized notification ratio is significantly above or below the country’s average, respectively. The spatial distribution of MDR- and non-MDR-TB was not homogeneous across the country. Age-standardized notification rates of MDR-TB ranged from 0.08 to 1.20 and of non-MDR-TB ranged from 7.73 to 83.03 notifications per 100,000 population across the municipalities. We identified 36 high-risk areas for non-MDR-TB and 8 high-risk areas for MDR-TB, which were simultaneously high-risk areas for non-MDR-TB. We found a moderate correlation (ρ = 0.653; 95% CI 0.457–0.728) between MDR- and non-MDR-TB standardized notification ratios. We found heterogeneity in the spatial distribution of MDR-TB across municipalities and we identified priority areas for intervention against TB. We recommend including geographical criteria in the application of molecular drug resistance to provide early MDR-TB diagnosis, in high-risk areas.

HIV Coinfection Is Associated with Low-Fitness rpoB Variants in Rifampicin-Resistant Mycobacterium tuberculosis

We analyzed 312 drug-resistant genomes of Mycobacterium tuberculosis isolates collected from HIV-coinfected and HIV-negative TB patients from nine countries with a high tuberculosis burden. We found that rifampicin-resistant M. tuberculosis strains isolated from HIV-coinfected patients carried disproportionally more resistance-conferring mutations in rpoB that are associated with a low fitness in the absence of the drug, suggesting these low-fitness rpoB variants can thrive in the context of reduced host immunity.

Prevalence, Predictors, and Successful Treatment Outcomes of Xpert MTB/RIF-identified Rifampicin-resistant Tuberculosis in Post-conflict Eastern Democratic Republic of the Congo, 2012-2017: A Retrospective Province-Wide Cohort Study

Background

Multidrug-resistant tuberculosis (MDR-TB) jeopardizes global TB control. The prevalence and predictors of Rifampicin-resistant (RR) TB, a proxy for MDR-TB, and the treatment outcomes with standard and shortened regimens have not been assessed in post-conflict regions, such as the South Kivu province in the eastern Democratic Republic of the Congo (DRC). We aimed to fill this knowledge gap and to inform the DRC National TB Program.

Methods

of adults and children evaluated for pulmonary TB by sputum smear microscopy and Xpert MTB/RIF (Xpert) from February 2012 to June 2017. Multivariable logistic regression, Kaplan–Meier estimates, and multivariable Cox regression were used to assess independent predictors of RR-TB and treatment failure/death.

Results

Of 1535 patients Xpert-positive for TB, 11% had RR-TB. Independent predictors of RR-TB were a positive sputum smear (adjusted odds ratio [aOR] 2.42, 95% confidence interval [CI] 1.63–3.59), retreatment of TB (aOR 4.92, 95% CI 2.31–10.45), and one or more prior TB episodes (aOR 1.77 per episode, 95% CI 1.01–3.10). Over 45% of RR-TB patients had no prior TB history or treatment. The median time from Xpert diagnosis to RR-TB treatment initiation was 12 days (interquartile range 3–60.2). Cures were achieved in 30/36 (83%) and 84/114 (74%) of patients on 9- vs 20/24-month MDR-TB regimens, respectively (P = .06). Predictors of treatment failure/death were the absence of directly observed therapy (DOT; adjusted hazard ratio [aHR] 2.77, 95% CI 1.2–6.66) and any serious adverse drug event (aHR 4.28, 95% CI 1.88–9.71).

Conclusions

Favorable RR-TB cure rates are achievable in this post-conflict setting with a high RR-TB prevalence. An expanded Xpert scale-up; the prompt initiation of shorter, safer, highly effective MDR-TB regimens; and treatment adherence support are critically needed to optimize outcomes.

Characterization of anti-BCG benz[α]anthraquinones and new siderophores from a Xinjiang desert-isolated rare actinomycete Nocardia sp. XJ31

Abstract

The current global demand for novel anti-TB drugs has drawn urgent attention on the discovery of natural product compounds with anti-TB activity. Lots of efforts have emphasized on environmental samples from unexplored or underexplored natural habits and identified numerous rare actinomycete taxa producing structurally diverse bioactive natural products. Herein, we report a survey of the rare actinobacteria diversity in Xinjiang region together with the discovery of anti-TB active natural products from these strains. We have collected 17 soil samples at different sites with different environmental conditions, from which 39 rare actinobacteria were identified by using a selective isolation strategy with 5 media variations. Among those isolated strains, XJ31 was identified as a new Nocardia sp. based on 16S rRNA gene analysis. Through one strain-many compounds (OSMAC) strategy combined with anti-Bacillus Calmette-Guérin bioassay-guided isolation, two groups of compounds were identified. They were twelve siderophores (nocardimicins, 1-12) and two anthraquinones (brasiliquinones, 13 and 14) and ten of them were identified as new compounds. The structures of the purified compounds were elucidated using HR-ESI-MS, 1D NMR, and 2D NMR techniques. The anti-TB bioassays revealed that the two benz[α]anthraquinones have potent activity against BCG (MICs = 25 μM), which can be used as a promising start point for further anti-TB drug development.

Key points

• Ten new natural products were identified from Nocardia sp. XJ31.

• Brasiliquinones13and14showed moderate anti-BCG activity.

Electronic supplementary material

The online version of this article (10.1007/s00253-020-10842-2) contains supplementary material, which is available to authorized users.

High Prevalence of Rifampicin Resistance Associated with Rural Residence and Very Low Bacillary Load among TB/HIV-Coinfected Patients at the National Tuberculosis Treatment Center in Uganda

Background

Rifampicin resistance (RR) is associated with mortality among tuberculosis (TB) patients coinfected with HIV. We compared the prevalence of RR among TB patients with and without HIV coinfection at the National Tuberculosis Treatment Center (NTTC) in Uganda, a TB/HIV high burdened country. We further determined associations of RR among TB/HIV-coinfected patients.

Methods

In this secondary analysis, we included adult (≥18 years) bacteriologically confirmed TB patients that were enrolled in a cross-sectional study at the NTTC in Uganda between August 2017 and March 2018. TB, RR, and bacillary load were confirmed by the Xpert® MTB/RIF assay in the primary study. A very low bacillary load was defined as a cycle threshold value of >28. We compared the prevalence of RR among TB patients with and without HIV coinfection using Pearson's chi-square test. We performed logistic regression analysis to determine associations of RR among TB/HIV-coinfected patients.

Results

Of the 303 patients, 182 (60.1%) were male, 111 (36.6%) had TB/HIV coinfection, and the median (interquartile range) age was 31 (25-39) years. RR was found among 58 (19.1%) patients. The prevalence of RR was 32.4% (36/111) (95% confidence interval (CI): 24-42) among TB/HIV-coinfected patients compared to 11.5% (22/192) (95% CI: 7–17) among HIV-negative TB patients (p < 0.001). Among TB/HIV-coinfected patients, those with RR were more likely to be rural residents (adjusted odds ratio (aOR): 5.24, 95% CI: 1.51–18.21, p = 0.009) and have a very low bacillary load (aOR: 13.52, 95% CI: 3.15–58.08, p < 0.001).

Conclusion

There was a high prevalence of RR among TB/HIV-coinfected patients. RR was associated with rural residence and having a very low bacillary load among TB/HIV-coinfected patients. The findings highlight a need for universal access to drug susceptibility testing among TB/HIV-coinfected patients, especially in rural settings.

Contributing risk factors towards the prevalence of multidrug-resistant tuberculosis in Malaysia: A systematic review

Multidrug-resistant tuberculosis (MDR-TB) is one of the causes of morbidity and mortality, among tuberculosis (TB) patients in Malaysia. The purpose of this study was to determine the contributing risk factors to the prevalence of (MDR-TB). Based on systematic review of the literatures, the prevalence of (MDR-TB) and associated risk factors in Malaysia were studied. A comprehensive search of Scopus, Science direct, PubMed, DOAJ, CINAHL Plus, MyJournal, BIREME, BMC Public Health, Medline, CAB, and WoS databases were done among the articles published from 31st January 2009 to 31st December 2018, by using medical subject heading (MeSH) key terms. In conducting this study, a total of 121 papers were reviewed and 23 research papers were chosen, because, they met the specific inclusion criteria. In this study, gender, age, marital status, ethnicity, homeless status, living in urban area and history of imprisonment were evaluated as demographic factors, while educational level and employment were evaluated as socioeconomic factors. Smoking, diabetes mellitus, drug abuse and alcohol consumption were evaluated as behavioral and co-morbidities factors. All the studies chosen as eligible to be included in this study were found to be significantly associated with the risk factors for the prevalence of (MDR-TB). It was also discovered that, lack of adequate knowledge among the community and (TB) patients might increase the progression of (MDR-TB) infection in Malaysia. Thus, carried out a systematic review provided a comprehensive assessment of the (MDR-TB) which might be useful for policy makers, health experts and researchers to implement appropriate strategies for (TB) infected population in Malaysia.

Drug-Resistant Tuberculosis and HIV Infection: Current Perspectives

Drug-resistant tuberculosis (DR-TB), including multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB), is considered a potential obstacle for elimination of TB globally. HIV coinfection with M/XDR-TB further complicates the scenario, and is a potential threat with challenging management. Reports have shown poor outcomes and alarmingly high mortality rates among people living with HIV (PLHIV) coinfected with M/XDR-TB. This coinfection is also responsible for all forms of M/XDR-TB epidemics or outbreaks. Better outcomes with reductions in mortality have been reported with concomitant treatment containing antiretroviral drugs for the HIV component and antitubercular drugs for the DR-TB component. Early and rapid diagnosis with genotypic tests, prompt treatment with appropriate regimens based on drug-susceptibility testing, preference for shorter regimens fortified with newer drugs, a patient-centric approach, and strong infection-control measures are all essential components in the management of M/XDR-TB in people living with HIV.

Multidrug-Resistant Tuberculosis in Patients with Human Immunodeficiency Virus. Management Considerations within High-resourced Settings

The management of multidrug-resistant tuberculosis (MDR TB) is notably complex among patients with human immunodeficiency virus (HIV). TB treatment recommendations typically include very little information specific to HIV and MDR TB, which often is derived from clinical trials conducted in low-resource settings. Mortality rates among patients with HIV and MDR TB remain high. We reviewed the published literature and recommendations to synthesize possible patient management approaches demonstrated to improve treatment outcomes in high-resourced countries for patients with MDR TB and HIV. Approaches to diagnostic testing, impact and timing of antiretroviral therapy on mortality, anti-MDR TB and antiretroviral drug interactions, and the potential role for short-course MDR TB therapy are examined. The combination of antiretroviral therapy with expanded TB drug therapy, along with the management of immune reconstitution inflammatory syndrome, other potential HIV-associated opportunistic diseases, and drug toxicities, necessitate an integrated multidisciplinary patient care approach using public health case management and provider expertise in drug-resistant TB and HIV management.

Treatment outcomes and antiretroviral uptake in multidrug-resistant tuberculosis and HIV co-infected patients in Sub Saharan Africa: a systematic review and meta-analysis

BACKGROUND

Multidrug-resistant tuberculosis (MDR-TB) in HIV endemic settings is a major threat to public health. MDR-TB is a substantial and underreported problem in Sub-Saharan Africa (SSA), with recognised cases projected to increase with advancement in diagnostic technology. There is paucity of review evidence on treatment outcomes and antiretroviral (ART) uptake among MDR-TB patients with HIV in SSA. To address this gap a review of treatment outcomes in HIV patients co-infected with MDR-TB in the SSA region was undertaken.

METHODS

Three databases (Medline, Web of Science, CINHAL), Union on Lung Heath conference proceedings and grey literature were searched for publications between January 2004 and May 2018. Records were assessed for eligibility and data extracted. Random effect meta-analysis was conducted using STATA and Cochrane's review manager.

RESULTS

A total of 271 publications were identified of which nine fulfilled the inclusion criteria. Data was collected from 3368 MDR-TB and HIV co-infected patients from four SSA countries; South Africa (6), Lesotho (1), Botswana (1) and Ethiopia (1). The most common outcome was cure (34.9% cured in the pooled analysis), this was followed by death (18.1% in pooled analysis). ART uptake was high, at 83% in the pooled analysis. Cure ranged from 28.6 to 54.7% among patients on ART and from 22.2 to 57.7%  among those not on ART medication. MDR-TB and HIV co-infected patients were less likely to be successfully treated than HIV negative MDR-TB patients (Risk Ratio = 0.87, 95% CI 0.97, 0.96).

CONCLUSION

Treatment outcomes for MDR-TB and HIV co-infected patients do not vary widely from those reported globally. However, treatment success was lower among HIV positive MDR-TB patients compared to HIV negative MDR-TB patients. Prompt antiretroviral initiation and interventions to improve treatment adherence are necessary.

Challenges of TB and HIV co-treatment: updates and insights

PURPOSE OF REVIEW

In the past few years, tuberculosis (TB) has overtaken HIV as the infectious disease with the highest global mortality. Successful management of this syndemic will require improved diagnostic tests, shorter preventive therapies, and more effective treatments, particularly in light of drug-resistant TB.

RECENT FINDINGS

Results from several major studies have been published or presented recently, including the development of a more sensitive rapid, molecular assay for TB; several new symptom-based screening tools; use of a 1-month regimen for TB prevention; the results of early vs. delayed TB preventive therapy for pregnant women; newer drugs and regimens for multidrug-resistant tuberculosis; and pharmacokinetic, safety, and efficacy studies of new HIV drugs in combination with TB treatment. We reviewed each of these topic areas and summarize relevant findings for the management of TB and HIV co-infection.

SUMMARY

Moving forward, as new treatment regimes for HIV or TB are developed, consideration of the HIV-TB co-infected patient must figure prominently, both when determining the diagnostic tests employed and to assess properly the drug-drug and drug-disease interactions that influence dosing, safety, and response.

Potential drug-drug interactions between antiretroviral therapy and treatment regimens for multi-drug resistant tuberculosis: Implications for HIV care of MDR-TB co-infected individuals

HIV-positive TB co-infected patients are at increased risk of multidrug-resistant (MDR)-TB compared to HIV-negative patients. Co-treatment of MDR-TB and HIV is common particularly in Sub-Saharan Africa where the co-morbidity is endemic. We discuss potential cellular metabolic pathway-mediated drug-drug interactions and the possible effect on HIV treatment outcomes of commonly prescribed antiretroviral therapy.

Dual activity of niclosamide to suppress replication of integrated HIV-1 and Mycobacterium tuberculosis (Beijing)

The human immunodeficiency virus (HIV) pandemic is driving the re-emergence of tuberculosis (TB) as a global health threat, both by increasing the susceptibility of HIV-infected people to infection with Mycobacterium tuberculosis (Mtb), and increasing the rate of emergence of drug-resistant Mtb. There are several other clinical challenges for treatment of co-infected patients including: expense, pill burden, toxicity, and malabsorption that further necessitate the search for new drugs that may be effective against both pathogens simultaneously. The anti-helminthic niclosamide has been shown to have activity against a laboratory strain of Mtb in liquid culture while bacteriostatic activity against non-replicating M. abscessus was also recently described. Here we extend these findings to further demonstrate that niclosamide inhibits mycobacterial growth in infected human macrophages and mediates potent bacteriostatic activity against the virulent Mtb Beijing strain. Importantly, we provide the first evidence that niclosamide inhibits HIV replication in human macrophages and Jurkat T cells through post-integration effects on pro-virus transcription. The dual antiviral and anti-mycobacterial activity was further observed in an in vitro model of HIV and Mtb co-infection using human primary monocyte-derived macrophages. These results support further investigation of niclosamide and derivatives as anti-retroviral/anti-mycobacterial agents that may reduce clinical challenges associated with multi-drug regimens and drug resistance.

Risk factors for multidrug-resistant tuberculosis in northwest Ethiopia: A case-control study

Ethiopia is one of 30-high burden multidrug-resistant tuberculosis (MDR-TB) countries globally. The aim of this study was to describe the characteristics of patients with MDR-TB and to investigate risk factors for MDR-TB relative to having drug-susceptible tuberculosis (TB), in northwest Ethiopia. A hospital-based, unmatched case-control study was conducted. Cases were all MDR-TB patients (i.e., resistant to at least rifampicin and isoniazid) who were confirmed by culture and drug-susceptibility testing whilst enrolled on treatment at Gondar University Hospital. Controls were all drug-susceptible tuberculosis (DS-TB) patients who were confirmed by Gene Xpert MTB/RIF at Gondar University Hospital. Univariable and multivariable logistic regression models were used for comparisons, and odds ratios with 95% confidence intervals (CI) were computed to measure the strength of association between the dependent and independent variables. A total of 452 patients (242 MDR-TB and 210 DS-TB) were included in this study. The mean age of the study participants was 33 years (SD ± 14 years). Approximately one-fifth (78, 17%) of all study participants were human immunodeficiency virus (HIV) positive; 21% (51) of cases and 13% (27) of controls. Risk factors associated with MDR-TB were a history of previous TB treatment (Adjusted Odds Ratio (AOR): 83.8; 95% CI: 40.7, 172.5), low educational status (AOR: 5.32; 95% CI: 1.43, 19.81); and ages less than 20 years (AOR: 9.01; 95% CI: 2.30, 35.25) and 21-30 years (AOR: 2.61; 95% CI: 1.02, 6.64). HIV infection was also significantly associated with MDR-TB among new TB patients (AOR: 5.55; 95% CI: 1.17, 26.20). This study shows that clinical and demographic features can be used to indicate higher risks of drug resistance in this setting.

Rifampicin-resistant tuberculosis among known HIV-infected patients in Oyo State, Nigeria

A major opportunistic infection among HIV-infected people is tuberculosis (TB). It accelerates the deadly progression of HIV which results in further decline in the patient's immune status and early death. More than 9 million people suffer from this debilitating coinfection worldwide. More worrisome is the fact that some patients now develop resistance to rifampicin, a first-line drug against TB. This study therefore aimed at determining the rifampicin-resistant TB prevalence rate among known HIV-positive patients in Oyo State. This cross-sectional study was performed by collecting suitable sputum samples from 397 known HIV patients who attended ART Clinic between January and December 2017. The samples were analyzed using the GeneXpert machine, a real-time polymerase chain reaction-based equipment. Of the total 397 tested, 172 (43.3%) were male while 225 (56.7%) were females. Fifty (12.6%) of the 397 known HIV patients tested positive to TB and 6 (12%) of the 50 were resistant to rifampicin. Four (2.3%) of the 172 males had rifampicin-resistant TB and 2 (0.9%) of the 225 females were resistant to rifampicin. Age group 31-40 years was the most affected with pulmonary TB while age group 10-20 years was the most affected with rifampicin-resistant TB. Six (1.5%) of the total 397 were rifampicin resistant. In conclusion, strict compliance with the infection control measures is strongly advocated for to prevent further transmission of Mycobacterium tuberculosis to people living with HIV most of whom have their immune system already weakened.

Evaluation of Xpert MTB-RIF guided diagnosis and treatment of rifampicin-resistant tuberculosis in Indonesia: A retrospective cohort study

BACKGROUND

Rifampicin-resistant tuberculosis (RR-TB) is largely underdetected in Indonesia. Xpert MTB/RIF (Xpert) has recently been introduced, prioritizing patients at risk of RR-TB, followed by phenotypic drug-susceptibility (DST) if rifampicin resistance is detected.

OBJECTIVE

This study investigated Xpert-based management of presumptive RR-TB cases under routine practice in West Java, Indonesia.

METHODS

We examined all records of patients tested with Xpert in the referral hospital for West Java in 2015-2016. We measured loss across a limited cascade of care, time to Xpert diagnosis and the commencement of initial second-line treatment, and identified factors associated with diagnostic and treatment delay. Additionally, we analyzed the appropriateness of treatment according to DST results.

RESULTS

Of 3415 patients with presumptive RR-TB, 3215 (94%) were tested by Xpert, of whom 339 (10.5%) were diagnosed as RR-TB. 288 (85%) of 339 RR-TB patients started initial second-line TB treatment, with 48 (14%) patients being lost between diagnosis and pre-treatment assessment. Second-line treatment was commenced at a median of 41 days (IQR 29-70) after RR-TB diagnosis. Delays in both diagnosis and treatment initiation were observed in 104 (52%) of 201 RR-TB patients with identifiable referral date. Rural residence was associated with delay to diagnosis (adjusted OR 2.7; 95%CI 1.5-5.2) and treatment initiation (adjusted OR 2.0; 1.2-3.4). Of 162 patients with available DST result, 107 (66%) had multidrug-resistant tuberculosis (MDR-TB) and 32 (20%) had either pre-extensively drug resistant (pre-XDR) or extensively drug resistant tuberculosis (XDR-TB). We estimated that with the current algorithm 41% of pre-XDR or XDR-TB patients are diagnosed, and 33% of them started on an appropriate treatment regimen.

CONCLUSIONS

Many patients with Xpert-diagnosed RR-TB either do not start MDR-TB treatment or encountered diagnostic and treatment delays under programmatic conditions in Indonesia, and most pre-XDR and XDR-TB cases remain undiagnosed. Further expansion and ongoing quality improvement of RR-TB services are urgently needed.

Clinical risk factors associated with multidrug-resistant tuberculosis (MDR-TB) in Mali

Background

MDR-TB is a major threat to global TB control. In 2015, 580,000 were treated for MDR-TB worldwide. The worldwide roll-out of GeneXpert MTB/RIF^® has improved diagnosis of MDR-TB; however, in many countries laboratories are unable to assess drug resistance and clinical predictors of MDR-TB could help target suspected patients. In this study, we aimed to determine the clinical factors associated with MDR-TB in Bamako, Mali.

Methods

We performed a cross-sectional study of 214 patients with presumed MDR-TB admitted to University of Bamako Teaching Hospital, Point-G between 2007 and 2016. We calculated crude and adjusted odds ratios for MDR-TB disease diagnosis using SPSS.

Results

We found that age ≤40years (OR = 2.56. 95% CI: 1.44–4.55), two courses of prior TB treatment (OR = 3.25,95% CI: 1.44–7.30), TB treatment failure (OR = 3.82,95% CI 1.82–7.79), sputum microscopy with 3+ bacilli load (OR = 1.98, 95% CI: 1.13–3.48) and a history of contact with a TB patient (OR = 2.48, 95% CI: 1.11–5.50) were significantly associated with confirmation of MDR-TB disease. HIV was not a risk factor for MDR-TB (aOR = 0.88, 95% CI: 0.34–1.94).

Conclusion

We identified several risk factors that could be used to identify MDR-TB suspects and prioritize them for laboratory confirmation. Prospective studies are needed to understand factors associated with TB incidence and clinical outcomes of TB treatment and disease.