Mortality and associated factors of patients with extensive drug-resistant tuberculosis: an emerging public health crisis in China

Pre-extensively drug-resistant and extensively drug-resistant tuberculosis in Latin America and the Caribbean: A systematic review and meta-analysis

BACKGROUND

The growing threat from pre-extensively drug-resistant tuberculosis (pre-XDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) poses a major public health concern in Latin America and the Caribbean (LAC). Therefore, this study aimed to summarize the available evidence on the prevalence of pre-XDR-TB and XDR-TB among patients with multidrug-resistant tuberculosis in LAC.

METHODS

A systematic review was conducted in the following databases on June 3, 2023: PubMed, Scopus, Ovid Medline, Web of Science, Scielo and LILACS. We estimated pooled proportions using a random effects model (Dersimonian and Laird). The 95% confidence intervals (95% CI) were calculated using the binomial exact method (Clopper-Pearson Method). Subgroup (by time period and country) and sensitivity analyses were performed.

RESULTS

Twenty-nine studies were eligible for qualitative synthesis and 27 for meta-analysis (n = 15,565). The pooled prevalence of XDR-TB in the study participants was 5% (95% CI: 3%-6%), while that of pre-XDR-TB was 10% (95% CI 7%-14%). Cuba (6%, 95% CI 0%-17%) and Peru (6%, 95% CI 5%-7%) had the highest pooled prevalence of XDR-TB. Regarding pre-XDR-TB, Brazil (16%, 95% CI 11%-22%) and Peru (13%, 95% CI: 9%-16%) showed the highest prevalence.

CONCLUSIONS

The pooled prevalence of pre-XDR-TB and XDR-TB in LAC was 10% and 5%, respectively. Governments should strengthen drug-resistance surveillance and TB programs.

Mortality rate and associated factors among patients co-infected with drug resistant tuberculosis/HIV at Mulago National Referral Hospital, Uganda, a retrospective cohort study

Drug resistant tuberculosis (DR-TB)/HIV co-infection remains a growing threat to public health and threatens global TB and HIV prevention and care programs. HIV is likely to worsen the outcomes of DR-TB and DR-TB is likely to worsen the outcomes of HIV despite the scale up of TB and HIV services and advances in treatment and diagnosis. This study determined the mortality rate and factors associated with mortality among persons on treatment co-infected with drug resistant TB and HIV at Mulago National Referral Hospital. We retrospectively reviewed data of 390 persons on treatment that had a DR-TB/HIV co-infection in Mulago National Referral Hospital from January 2014 to December 2019.Modified poisson regression with robust standard errors was used to determine relationships between the independent variables and the dependent variable (mortality) at bivariate and multivariate analysis. Of the 390 participants enrolled, 201(53.9%) were males with a mean age of 34.6 (±10.6) and 129 (33.2%,95% CI = 28.7-38.1%) died. Antiretroviral therapy(ART) initiation (aIRR 0.74, 95% CI = 0.69-0.79), having a body mass index (BMI)≥18.5Kg/m2 (aIRR 1.01, 95% CI = 1.03-1.17), having a documented client phone contact (aIRR 0.85, 95% CI = 0.76-0.97), having a mid-upper arm circumference,(MUAC) ≥18.5cm (aIRR 0.90, 95% CI = 0.82-0.99), being on first and second line ART regimen (aIRR 0.83, 95% CI = 0.77-0.89),having a known viral load (aIRR 1.09, 95% CI = 1.00-1.21) and having an adverse event during the course of treatment (aIRR 0.88, 95% CI = 0.83-0.93) were protective against mortality. There was a significantly high mortality rate due to DR-TB/HIV co-infection. These results suggest that initiation of all persons living with HIV/AIDS (PLWHA) with DR-TB on ART and frequent monitoring of adverse drug events highly reduces mortality.

Risk Factors for Poor Outcomes Among Patients with Extensively Drug-Resistant Tuberculosis (XDR-TB): A Scoping Review

In recent years, there has been an upsurge in cases of drug-resistant TB, and strains of TB resistant to all forms of treatment have begun to emerge; the highest level of resistance is classified as extensively drug-resistant tuberculosis (XDR-TB). There is an urgent need to prevent poor outcomes (death/default/failed treatment) of XDR-TB, and knowing the risk factors can inform such efforts. The objective of this scoping review was to therefore identify risk factors for poor outcomes among XDR-TB patients. We searched three scientific databases, PubMed, Scopus, and ProQuest, and identified 25 articles that examined relevant risk factors. Across the included studies, the proportion of patients with poor outcomes ranged from 8.6 to 88.7%. We found that the most commonly reported risk factor for patients with XDR-TB developing poor outcomes was having a history of TB. Other risk factors were human immunodeficiency virus (HIV), a history of incarceration, low body mass, being a smoker, alcohol use, unemployment, being male, and being middle-aged. Knowledge and understanding of the risk factors associated with poor outcomes of XDR-TB can help policy makers and organizations in the process of designing and implementing effective programs.

Whole-genome epidemiology and characterisation of mcr-1-encoding Escherichia coli in aquatic bird farms from the Pearl River Delta, China, 2019-2020

Due to their unique breeding pattern, aquatic bird farms are increasingly considered as hotspots in the development and spread of antimicrobial resistance. However, comprehensive studies addressing the whole-genomic features of colistin-resistant bacteria in aquatic bird farms are scarce. Over a 2-year period, we conducted surveillance to determine the whole-genome epidemiology and characterisation of mcr-1-positive Escherichia coli in aquatic bird farms in southeastern coastal China. A total of 100 mcr-1-producing isolates among 654 E. coli strains were recovered from 781 samples collected in 11 aquatic bird farms and 1 veterinary clinic in the Pearl River Delta area. Higher resistance phenotypes to 17 antibiotics were found in mcr-1-positive isolates compared with other isolates. Subsequently, 20 mcr-1-carrying isolates were sequenced to analyse the whole-genomic features. Molecular typing as well as antimicrobial resistance gene and virulence factor profiles of the isolates showed considerable diversity. Three types of genetic backbones of mcr-1 in the isolates were assembled and were identified in diverse broad-host-range plasmids and bacterial species. Pangenome analyses revealed a large genetic pool composed of the isolates. Furthermore, phylogenetic trees both of the isolates in this study and a global data set were built, indicating the spread of the three mcr-1 backbones and the mcr-1-positive isolates among different habitats, farms and even countries. This study highlights that aquatic bird farms may act as an important reservoir for mcr-1-producing E. coli, from which colistin resistance may be spread to diverse habitats, different geographical locations and even across bacterial species.

Tuberculosis: An Update on Pathophysiology, Molecular Mechanisms of Drug Resistance, Newer Anti-TB Drugs, Treatment Regimens and Host- Directed Therapies

Human tuberculosis (TB) is primarily caused by Mycobacterium tuberculosis (Mtb) that inhabits inside and amidst immune cells of the host with adapted physiology to regulate interdependent cellular functions with intact pathogenic potential. The complexity of this disease is attributed to various factors such as the reactivation of latent TB form after prolonged persistence, disease progression specifically in immunocompromised patients, advent of multi- and extensivelydrug resistant (MDR and XDR) Mtb strains, adverse effects of tailor-made regimens, and drug-drug interactions among anti-TB drugs and anti-HIV therapies. Thus, there is a compelling demand for newer anti-TB drugs or regimens to overcome these obstacles. Considerable multifaceted transformations in the current TB methodologies and molecular interventions underpinning hostpathogen interactions and drug resistance mechanisms may assist to overcome the emerging drug resistance. Evidently, recent scientific and clinical advances have revolutionised the diagnosis, prevention, and treatment of all forms of the disease. This review sheds light on the current understanding of the pathogenesis of TB disease, molecular mechanisms of drug-resistance, progress on the development of novel or repurposed anti-TB drugs and regimens, host-directed therapies, with particular emphasis on underlying knowledge gaps and prospective for futuristic TB control programs.

Predictors of mortality in patients with drug-resistant tuberculosis: A systematic review and meta-analysis

BACKGROUND

Even though the lives of millions have been saved in the past decades, the mortality rate in patients with drug-resistant tuberculosis is still high. Different factors are associated with this mortality. However, there is no comprehensive global report addressing these risk factors. This study aimed to determine the predictors of mortality using data generated at the global level.

METHODS

We systematically searched five electronic major databases (PubMed/Medline, CINAHL, EMBASE, Scopus, Web of Science), and other sources (Google Scholar, Google). We used the Joanna Briggs Institute Critical Appraisal tools to assess the quality of included articles. Heterogeneity assessment was conducted using the forest plot and I2 heterogeneity test. Data were analyzed using STATA Version 15. The pooled hazard ratio, risk ratio, and odd's ratio were estimated along with their 95% CIs.

RESULT

After reviewing 640 articles, 49 studies met the inclusion criteria and were included in the final analysis. The predictors of mortality were; being male (HR = 1.25,95%CI;1.08,1.41,I2;30.5%), older age (HR = 2.13, 95%CI;1.64,2.62,I2;59.0%,RR = 1.40,95%CI; 1.26, 1.53, I2; 48.4%) including a 1 year increase in age (HR = 1.01, 95%CI;1.00,1.03,I2;73.0%), undernutrition (HR = 1.62,95%CI;1.28,1.97,I2;87.2%, RR = 3.13, 95% CI; 2.17,4.09, I2;0.0%), presence of any type of co-morbidity (HR = 1.92,95%CI;1.50-2.33,I2;61.4%, RR = 1.61, 95%CI;1.29, 1.93,I2;0.0%), having diabetes (HR = 1.74, 95%CI; 1.24,2.24, I2;37.3%, RR = 1.60, 95%CI;1.13,2.07, I2;0.0%), HIV co-infection (HR = 2.15, 95%CI;1.69,2.61, I2; 48.2%, RR = 1.49, 95%CI;1.27,1.72, I2;19.5%), TB history (HR = 1.30,95%CI;1.06,1.54, I2;64.6%), previous second-line anti-TB treatment (HR = 2.52, 95% CI;2.15,2.88, I2;0.0%), being smear positive at the baseline (HR = 1.45, 95%CI;1.14,1.76, I2;49.2%, RR = 1.58,95%CI;1.46,1.69, I2;48.7%), having XDR-TB (HR = 2.01, 95%CI;1.50,2.52, I2;60.8%, RR = 2.44, 95%CI;2.16,2.73,I2;46.1%), and any type of clinical complication (HR = 2.98, 95%CI; 2.32, 3.64, I2; 69.9%). There are differences and overlaps of predictors of mortality across different drug-resistance categories. The common predictors of mortality among different drug-resistance categories include; older age, presence of any type of co-morbidity, and undernutrition.

CONCLUSION

Different patient-related demographic (male sex, older age), and clinical factors (undernutrition, HIV co-infection, co-morbidity, diabetes, clinical complications, TB history, previous second-line anti-TB treatment, smear-positive TB, and XDR-TB) were the predictors of mortality in patients with drug-resistant tuberculosis. The findings would be an important input to the global community to take important measures.

Malnutrition prevalence and associated biochemical factors among drug-resistance tuberculosis (DR-TB) patients at key treatment sites in Conakry City, Republic of Guinea

Introduction

drug-resistant tuberculosis is a major global health problem and a threat to health security given the increase in the number of cases and the challenges associated with care. Besides, the relationship between poor nutritional status and tuberculosis is clearly established. For relevant and evidence-based public health decision-making regarding the management of malnutrition in patients with drug-resistant tuberculosis in the initial phase, it is essential to estimate the prevalence of malnutrition and understand the risk factors associated with it.

Methods

we performed a retrospective cohort study in drug-resistant tuberculosis patients aged 18 years and older, among which the nutritional status was assessed through BMI. All predictors were included in a prediction model using the multivariate logistic model according to the lowest Akaike criterion. Discrimination and model calibration was evaluated using receiver performance analysis, and the Hosmer and Lemeshow test.

Results

this study revealed a prevalence of malnutrition of 64.7% in drug-resistant tuberculosis patients in our 218-patient series. The factors associated with malnutrition were: unsuccessful treatment, the active presence of mycobacterium tuberculosis, increased bacteriological conversion time, increased serum creatinine, increased transaminase SGPT of the liver, and anaemia. Some of the factors not associated with malnutrition included the history of anti-tuberculosis treatment, vomiting, hepatic SGPT, initial AFB count, smear and culture conversion time, depression, and chest X-ray.

Conclusion

malnutrition remains a concern among drug-resistant tuberculosis patients in Guinea as it affects more than half of them with a negative impact on the outcome of treatment. Implementing specific interventions for these high-risk patients, including nutritional supplementation, psychosocial support, and treatment for tuberculosis, can improve management for better treatment outcomes.

Poor treatment outcome and its predictors among drug-resistant tuberculosis patients in Ethiopia: A systematic review and meta-analysis

OBJECTIVE

To assess poor treatment outcomes and their predictors among drug-resistant tuberculosis patients treated in Ethiopia.

METHODS

Data were searched from both electronic databases and other sources. From the whole search, 404 articles were reviewed and 17 articles that fulfilled the inclusion criteria were included in the analysis. Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist was followed and Joanna Briggs Institute Critical Appraisal checklist was used for assessing the quality. Risk of bias was assessed using forest plot and Egger's regression test. Data were analyzed using STATA version 15 and Review Manager Software version 5.3.

RESULTS

The overall pooled proportion of poor treatment outcome and mortality was 17.86% and 15.13% respectively. The incidence density rate of poor treatment outcome and mortality was 10.41/1000 person-months and 9.28/1000 person-months respectively. Survival status and successful treatment outcomes were 76.97% and 63.82% respectively. HIV positivity, non-HIV comorbidities, clinical complications, extrapulmonary involvement, undernutrition, anemia, treatment delay, lower body weight, and older age were the predictors of poor treatment outcome.

CONCLUSION

Better survival and treatment success rates were noted in Ethiopia as compared to the global average. The majority of the poor treatment outcomes occurred within the intensive phase. Early initiation of anti-tuberculosis treatment would be important for successful treatment outcomes.

Combining interferon- release assays with lymphocyte enumeration for diagnosis of Mycobacterium tuberculosis infection

Objective

To investigate the possibility of combining tuberculosis (TB)-interferon (IFN)-γ release assays (IGRAs) with lymphocyte enumeration for diagnosis of Mycobacterium tuberculosis infection.

Methods

We performed a retrospective study of 166 TB patients [68 patients with pulmonary tuberculosis TB (PTB) and 98 patients with extra-pulmonary TB (EPTB)] diagnosed in our hospital between January 2016 and May 2018 along with 377 non-TB patients. The diagnostic performance of the TB-IGRA was evaluated using receiver operating characteristic (ROC) curves. Youden’s index was used to determine the optimal cut-off threshold.

Results

IFN-γ release in patients with PTB and EPTB were dramatically higher compared with non-TB patients (203.58±18.00 pg/mL, 201.83±14.56 pg/mL and 32.12±4.36 pg/mL, respectively). IFN-γ release was positively correlated with lymphocyte counts and percentages in patients with PTB (r = 0.252 and r = 0.278, respectively) and EPTB (r = 0.229 and r = 0.298, respectively). No correlation was observed in non-TB patients. The area under the ROC curve for TB-IGRA was 0.884. When the optimal cut-off value for IFN-γ (14 pg/mL, Youden’s index 0.661) was applied, the sensitivity was 88.6% and the specificity was 77.5%.

Conclusions

Combining TB-IGRA with lymphocyte enumeration was effective for diagnosis of early-stage Mycobacterium tuberculosis infection.

Associations of ambient air pollutants with regional pulmonary tuberculosis incidence in the central Chinese province of Hubei: a Bayesian spatial-temporal analysis

BACKGROUND

Air pollution and pulmonary tuberculosis (PTB) are still serious worldwide problems, especially in areas of developing countries. Whether there is an association between high ambient air pollutant concentrations and PTB has not been fully explored.

METHODS

Bayesian spatial-temporal models were constructed to analyse the association between ambient air pollutants (particulate matter with aerodynamic diameters of ≤10 μm (PM₁₀), sulfur dioxide (SO₂) and nitrogen dioxide (NO₂)) and PTB incidence, adjusting for socioeconomic covariates. We collected data on pulmonary TB, ambient air pollution (PM₁₀, SO₂ and NO₂) concentrations and socioeconomic covariates from 17 prefectures in the central Chinese province of Hubei between Jan 1, 2006, and Dec 31, 2015.

RESULTS

For every annual 10 μg/m³ increase in SO₂, the relative risk (RR) of PTB incidence was 1.046 (95% credible interval [CI], 1.038-1.054) in the study area. Moreover, we found positive associations with each annual 10 μg/m³ increase in ambient air pollutants (PM₁₀, SO₂ and NO₂) in females but only with SO₂ in males. A significant association for each 10 μg/m³ increase in SO₂ was observed in all the age groups, with a significant association for PM₁₀ only in children under 14 years of age. A significant response relationship was also observed at a 0-1 month moving average lag for each 10 μg/m³ increase in SO₂.

CONCLUSIONS

High ambient air pollution concentrations in areas of developing countries might increase the risk of regional PTB incidence, especially for women and young people. Precautions and protective measures and efforts to reduce ambient air pollutant concentrations should be strengthened in developing countries.