Tuberculosis and chronic respiratory disease: a systematic review

Vaccination in post-tuberculosis lung disease management: A review of the evidence

INTRODUCTION AND OBJECTIVES

Post-tuberculosis lung disease (PTLD), as other chronic respiratory disorders, may have infectious complications; some of them can be prevented with vaccinations. So far, no document has discussed the potential role of vaccination in PTLD. Therefore, the objective of this review was to describe vaccination recommendations to prevent infections potentially capable of complicating PTLD.

MATERIALS AND METHODS

A non-systematic review of the literature was conducted. The following keywords were used: tuberculosis, vaccination, vaccines and PTLD. PubMed/MEDLINE and Embase were used as the search engine, focusing on English-language literature only.

RESULTS

We identified 9 vaccines potentially useful in PTLD. Influenza, pneumococcal and anti-COVID-19 vaccinations should be recommended. Patients with PTLD can also benefit from vaccination against shingles. Vaccination against pertussis is mainly relevant during childhood. Diphtheria, tetanus and measles vaccination are recommended for general population and should be considered in patients with PTLD not previously vaccinated. Tdap (Tetanus, diphtheria, and pertussis) booster should be repeated in every adult every ten years. Vaccination against BCG retains its importance during early childhood in countries where TB is endemic.

CONCLUSIONS

Vaccination deserves to be considered among the strategies to prevent and/or mitigate PTLD complications. Further evidence is necessary to better understand which vaccines have the greatest impact and cost-benefit.

Integrated Bioinformatic Analyses Constructed a Novel Immune Escape-Related Signature and Classifier to Predict Tuberculosis

Despite its high preventability and curability, tuberculosis (TB) remains a leading cause of morbidity and mortality worldwide. One factor that contributes to the susceptibility and progression of various diseases is immune escape. Therefore, the primary aim of our study was to explore the involvement of immune escape-related genes in the pathogenesis of TB. Two TB datasets retrieved from the gene expression omnibus database were used to identify differentially expressed genes (DEGs). Machine learning was used to identify the hub immune escape-related genes (HIERGs). Weighted gene co-expression network analysis supported and further validated these findings. Subsequently, we scrutinised two distinct subgroups that were determined through the identification of hub immune escape-related genes, and evaluated the distinct function of the subgroups. Our study identified a total of 11 genes related to immune escape in TB. Additionally, six HIERGs were identified through the least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) algorithms. Diagnostic models constructed using HIERGs exhibited high accuracy. Two immune escape-related subclusters were identified in TB samples, which delineated differences in immune infiltration cells with the distinct TB subgroups. The heightened expression of six HIERGs serves as a significant risk factor for TB. The six HIERGs also contribute towards the development of TB-related diseases. Our findings demonstrate a significant enrichment of immune escape-related gene expression in individuals with TB, suggesting a close relationship between immune escape activity and immune cell abundance. These results underscore the putative role of immune escape in the advancement of TB by disrupting or perturbing the immune response.

Tuberculosis-associated respiratory impairment and disability in children, adolescents and adults: protocol for a systematic review and individual participant data meta-analysis

BACKGROUND

Approximately 2% of the global population has survived tuberculosis (TB). Increasing evidence indicates that a significant proportion of pulmonary TB survivors develop TB-associated respiratory impairment and disability-commonly referred to as post-TB lung disease-marked by impaired respiratory function, persistent symptoms and activity limitations. However, the prevalence, risk factors and progression of TB-associated respiratory disability throughout the life course are not well understood. To address these gaps, we will undertake a systematic review and individual participant-level data meta-analysis (IPD-MA) focusing on TB-associated respiratory impairment and disability in children, adolescents and adults successfully treated for pulmonary TB.

METHODS AND ANALYSIS

We will systematically search MEDLINE, Embase, CENTRAL, Global Index Medicus and medRxiv for original studies investigating TB-associated respiratory impairment and disability in people of all ages who have completed treatment for microbiologically confirmed or clinically diagnosed pulmonary TB. Authors of eligible studies will be invited to contribute deidentified data and form a collaborative group. Primary outcomes will be (1) abnormal lung function based on spirometry parameters and (2) chronic respiratory symptoms. We will estimate the overall and subgroup-specific prevalence of each outcome through IPD-MA. Next, we will develop clinical prediction tools assessing the risk of future TB-associated respiratory impairment and disability. Finally, we will use stepwise hierarchical modelling to identify epidemiological determinants of respiratory impairment and disability.

ETHICS AND DISSEMINATION

This study has been approved by the ethics review boards at the Rhode Island Hospital (2138217-2) and the Research Institute of the McGill University Health Centre (2024-10345). Individual study authors will be required to obtain institutional approval prior to sharing data. Results will be disseminated through open-access, peer-reviewed publications and conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42024529906.

Tuberculosis

Tuberculosis is a leading cause of death globally. Given the airborne transmission of tuberculosis, anybody can be infected, but people in high-incidence settings are more exposed. Risk of progression to disease is higher in the first years after infection, and in people with undernourishment, immunosuppression, or who smoke, drink alcohol, or have diabetes. Although cough, fever, and weight loss are hallmark symptoms, people with tuberculosis can be asymptomatic, so a high index of suspicion is required. Prompt diagnosis can be made by sputum examination (ideally with rapid molecular tests), but chest radiography can be helpful. Most people with disease can be treated with regimens of 6 months or less; longer regimens may be necessary for those with drug resistance. Central to successful treatment is comprehensive, person-centred care including addressing key determinants, such as undernourishment, smoking, and alcohol use, and optimising management of comorbidities, such as diabetes and HIV. Care should continue after treatment ends, as long-term sequelae are common. Prevention relies mostly on treatment with rifamycin-based regimens; current vaccines have limited efficacy. Ongoing research on shorter and safer regimens for infection and disease treatment, and simpler and more accurate diagnostic methods will be key for tuberculosis elimination.

The role of neutrophil response in lung damage and post-tuberculosis lung disease: a translational narrative review

It is estimated that more than 150 million individuals alive in 2020 had survived tuberculosis (TB). A portion of this large population continues to experience chronic respiratory abnormalities, with or without symptoms, due to previous active pulmonary TB. This condition known as Post-TB Lung Disease (PTLD), involves a complex interaction between pathogen, host and environmental factors. These interactions are believed to drive a hyperinflammatory process in the lungs during active TB, resulting in tissue damage, which may lead to radiological sequelae, impaired pulmonary function, clinical symptoms, such as cough, dyspnea, hemoptysis, and respiratory infections. Such complications impose significant health, financial, and social burdens, which remain poorly understood and inadequately addressed by health care systems. Given the heterogeneity of immune cells and their products infiltrating the airways and the lung parenchyma during acute and chronic inflammation caused by Mycobacterium tuberculosis infection, it is evident that TB immunopathology is multifactorial. Among the various components involved, neutrophils have recently emerged as critical contributors to the deleterious immune response against TB, leading to severe pulmonary damage. In this translational narrative review, we aim to summarize the role of neutrophils and their primary products - proteases (such as elastase), matrix metalloproteinases and neutrophils extracellular traps (NETs) - in pulmonary TB. We highlight new concepts and emerging evidence of neutrophil involvement during the active disease, translating these insights from "bench to bedside" to facilitate dialogue between fundamental researchers and clinical practitioners. Additionally, we present potential targets for future treatment strategies that could mitigate or even prevent PTLD.

The prevalence and pattern of post tuberculosis lung disease including pulmonary hypertension from an Australian TB service; a single-centre, retrospective cohort study

INTRODUCTION

Post Tuberculosis Lung Disease (PTLD) is increasingly recognised as a significant cause of morbidity internationally, but has not been described in an Australian setting. We aimed to determine the prevalence of PTLD among adult TB survivors from an Australian TB service and describe the pattens of lung function abnormalities and pulmonary disease, including pulmonary hypertension.

METHODS

We conducted a single-centre retrospective cohort study in Sydney, Australia, including all adults who successfully completed TB treatment between January 2013 and December 2022. Baseline characteristics, post treatment pulmonary function, and thoracic computed tomography (CT) data were analysed to determine the prevalence and patterns of PTLD, defined as any lung function and/or radiological abnormality attributable to TB.

RESULTS

Among 119 confirmed TB patients (mean age 46 ± 21 years, 61% males) PTLD was identified in 81/119 (68%). Pulmonary function testing was available for 51/119 (43%), of whom 38/51(75%) exhibited abnormalities. Obstructive deficits were found in 25/51 (49%), restrictive deficits in 11/51 (22%), and impaired gas transfer capacity in 26/51 (51%). Chest CT scans were completed in 76/119 (64%), with 70/76 (92%) demonstrating significant abnormalities, including pulmonary fibrosis 43/76 (57%), bronchiectasis 22/76 (29%), and emphysema 11/76 (15%). Pulmonary hypertension was suspected in 52/76 (68%) patients based on radiological findings.

CONCLUSION

Despite successful treatment, PTLD was frequently observed among our cohort of Australian TB survivors. Further research into optimal screening practices to diagnose chronic pulmonary diseases and pulmonary hypertension could provide opportunities for earlier intervention and management.

Development of chronic obstructive pulmonary disease after a tuberculosis episode in a large, population-based cohort from Eastern China

BACKGROUND

Although smoking is considered the primary cause of chronic obstructive pulmonary disease (COPD), there is a growing realization that there may be important secondary risk factors. Tuberculosis may lead to lung impairment; however, whether residual lung damage results in clinically significant, long-term outcomes, independent of smoking, has not been well studied. We aimed to investigate the association between tuberculosis and the subsequent development of COPD using a large, population-based cohort study.

METHODS

We conducted a longitudinal cohort study within the Chinese Electronic Health Records Research in Yinzhou study between 2009 and 2021. We followed participants free of COPD at the beginning of the study, and investigated whether previous or current tuberculosis was an important risk factor. Tuberculosis was recorded based on the Chinese National Disease Reporting system which includes all diagnosed cases at the city, provincial and national levels. We assessed the relationship between tuberculosis and COPD using multivariable survival models, adjusting for demographic and lifestyle characteristics, education level, comorbidities and use of medications.

RESULTS

Among 477 046 participants, 198 882 were eligible for inclusion in our analysis. In a multivariable model, pulmonary tuberculosis and all tuberculosis were associated with a 2.57-fold [95% confidence interval (CI), 2.31-2.87)] and 1.67-fold (95% CI, 1.48-1.90) increased COPD risk, respectively. Stronger associations of pulmonary tuberculosis and all tuberculosis with COPD were seen in participants who were elderly, or with lower body mass index or education level (Pinteraction<0.001). People with tuberculosis were at an increased risk of COPD if they were current smokers [adjusted hazard ratio (aHR), 1.40; 95% CI, 1.02-1.93] or non-smokers (aHR, 1.72; 95% CI, 1.50-1.98).

CONCLUSIONS

Persons who developed tuberculosis were at much greater risk of developing COPD, even accounting for smoking and other potential confounders.

The Promise of Infrared Spectroscopy in Liquid Biopsies for Solid Cancer Detection

Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy has shown significant promise in the context of liquid biopsy, offering a potential tool for cancer diagnostics. Unlike traditional tissue biopsies, which may not fully capture the clonal heterogeneity of tumors, liquid biopsy reflects the dynamic state of the disease and its progression more comprehensively. Biofluids such as serum and plasma are low-cost, minimally invasive diagnostic media with well-established clinical uses. This review assesses the use of ATR-FTIR spectroscopy to detect biochemical changes in biofluids linked to various malignancies, including breast, ovarian, endometrial, prostate, bladder, kidney, pancreatic, colorectal, hepatic, esophageal, gastric, lung, and brain cancers. While ATR-FTIR offers the advantages of rapid, minimally invasive detection and real-time disease monitoring, its integration into clinical practice faces challenges, particularly in terms of reproducibility due to variability in sample preparation, spectral acquisition, and data processing. The translation of ATR-FTIR into routine diagnostics will require validation through large-scale cohort studies and multicenter trials to ensure its clinical reliability and effectiveness.

Prevalence of chronic respiratory diseases diagnosed by pulmonary function testing: a cross-sectional study

Background

Respiratory diseases are pathological conditions affecting the organs and tissues involved in gas exchange. Pulmonary function tests allow for the classification of the severity of respiratory diseases, their follow-up, and treatment response assessment. The aim was to determine the prevalence of chronic respiratory disease and the risk factors in Khartoum, Sudan.

Methods

A descriptive cross-sectional hospital-based study was conducted in the Respiratory Department from May to October 2021, including the patients who underwent pulmonary function tests. Data were analyzed using Statistical Package for Social Sciences, version 25.0.

Results

Out of the 396 study participants, 214 (54%) were above 40 years of age with similar gender distribution and a male-to-female ratio of 1.1: 1, and almost all were Sudanese. Clinically, 40.4% had normal body mass index (BMI), 24.2% underweight, and 13.6% were obese. Smokers represented 19.4% of the study participants. Moreover, 18.2% reported a positive history of bronchial asthma. Regarding pulmonary function test patterns, 50.8% exhibited normal results, 25.3% displayed restrictive patterns, 19.7% showed obstructive patterns, and 4.3% had mixed patterns. Chi-square cross-tabulation testing revealed a significant association between older ages of participants and the abnormal pulmonary function test results (P < 0.001).

Conclusion

The study revealed that the proportion of respiratory diseases with abnormal lung function test results is considerable and should not be ignored, especially among older patients. Therefore, when indicated, attention should be paid to performing lung function tests widely to accurately identify the prevalence rates of lung diseases and associated risk factors in Sudan.

The Western Pacific Regional Framework to End TB: overview and critical reflection

Despite notable progress, TB remains a critical public health challenge in the Western Pacific Region. To address this, the WHO developed the Western Pacific Regional Framework to End TB, which aligns with global health targets, such as the End TB Strategy and the Sustainable Development Goals. Here, we critically review the Framework, highlighting its strengths and ongoing challenges, with suggestions as to how it might adapt. Although the Framework offers a comprehensive strategy for reducing the TB burden, its success depends on effective implementation across diverse socio-economic contexts. Key obstacles include undiagnosed infectious TB cases, limited healthcare infrastructure, persistent inequities in access to TB services, and drug-resistant TB. The COVID-19 pandemic exacerbated these challenges, disrupting TB services and delaying progress towards 2030 targets. The Framework's reliance on multisectoral partnerships and innovative technologies presents opportunities but requires substantial political commitment, sustained funding and system-wide health reforms. Additionally, gaps remain in addressing social determinants of TB. Ensuring equity, maintaining political will, and fostering international collaboration are essential to overcoming these barriers. Continuous evaluation and adaptation will be crucial in ensuring the Framework's effectiveness in eliminating TB in the Region by 2030.

Factors associated with extrapulmonary tuberculosis in comparison to pulmonary tuberculosis in patients with and without HIV in Bogotá, Colombia: an observational study

Background

Extrapulmonary tuberculosis (EPTB) poses a public health challenge, particularly among individuals with human immunodeficiency virus (HIV). However, many EPTB cases arise in those without HIV, leaving the underlying factors unclear.

Objectives

This study aims to characterize patients with pulmonary tuberculosis (PTB) and EPTB, exploring the differences in associated factors for each type in patients with and without HIV.

Design

An analytical observational study was conducted on a cohort of tuberculosis (TB) patients diagnosed between 2014 and 2021 in a referral hospital in Bogotá, Colombia.

Methods

Patients were categorized into PTB or EPTB based on the site of infection. Data on demographic and clinical variables were collected, comparing the two groups. A multivariate logistic regression model was created to identify factors associated with EPTB compared to PTB.

Results

The study encompassed 533 patients: 310 with PTB and 223 with EPTB, of which only 65 (14.7%) were HIV positive. PTB patients exhibited higher rates of active smoking, smoking cessation, diabetes mellitus (DM), and other pulmonary diseases. The logistic regression identified HIV infection as the only factor associated with EPTB (OR 2.36 (1.54-3.61), p < 0.001). Conversely, quitting smoking (OR 0.58 (0.35-0.96) p = 0.038), DM (OR 0.41 (0.21-0.82) p = 0.011), chronic obstructive pulmonary disease (COPD) (OR 0.18 (0.08-0.4) p < 0.001), other pulmonary diseases (OR 0.21 (0.61-0.77) p = 0.019), or those using immunosuppressants (OR 0.44 (0.20-0.96) p = 0.04) exhibited a negative association with EPTB compared to PTB. Specific models for pleural and lymph node TB revealed distinct associations, with HIV strongly linked to lymph node TB (OR 3.38, 95% CI 1.57-7.26, p = 0.002).

Conclusion

EPTB is primarily associated with HIV infection, while smoking, DM, COPD, other pulmonary diseases, and immunosuppressant use are associated with PTB. Variability in associated factors for specific EPTB forms underlines the need for tailored research into the predisposing factors for EPTB, particularly in HIV-negative patients.

"You find yourself in a very humiliating situation": experiences of people living with post-tuberculosis lung disease in Brazil

Background

Brazil remains one of the 30 countries with the highest tuberculosis (TB) and TB-HIV coinfection burden. Post-TB lung disease (PTLD) is a set of sequelae that can occur in people who have been cured of TB.

Aim

To learn about the experiences of people living with PTLD (PLPTLD) and how healthcare workers (HCW) manage PTLD.

Methods

An exploratory qualitative study with a purposive sample of PLPTLD and HCW from two different cities. Open-ended interviews were conducted using a semi-structured interview guide, which were recorded and transcribed. Two researchers analyzed the interviews using an inductive approach and applied a content analysis framework to define categories.

Results

Forty-six participants were interviewed, and four categories emerged: PTLD as a social disease; stigma; the fragility of access; and limitations. The categories encompassed two main aspects like PTLD in activities of daily living and emotions in everyday life, for instance, challenges with preparing meals, getting a job, barriers to set clinical appointments or getting social assistance, and stigma.

Conclusion

This study reveals specific needs from patients and providers such as a lack of knowledge about PTLD, physical limitations, and stigmatization due to PTLD. It is crucial to address these issues in public health policies.

Clinical-Epidemiological Profile of Patients With Chronic Obstructive Pulmonary Disease Treated at the Pneumology Outpatient Clinic of a Brazilian University Hospital

Background Chronic obstructive pulmonary disease (COPD) is a significant illness that affects many Brazilians. It is a complex and extremely prevalent disease, and thus, understanding the clinical-epidemiological profile of the patients afflicted with this disease is of utmost importance for the adequate management of these patients by multidisciplinary teams. Objective The aim of the study was to describe the clinical and epidemiological profile of COPD patients in a specialized outpatient clinic. Methods This was a cross-sectional study. The sample comprised 198 patients who attended a specialized outpatient clinic in 2018. All variables were collected from the patients' medical records. Results The mean age of the patients was 69.56 ± 8.98 years (CI 95%: 68.30 - 70.82). Of the 198 patients, 115 (58.1%) were male, while 83 (41.9%) were female. Of all patients, 158 (79.8%) were active smokers or former smokers. The mean value for the forced expiratory volume in the first second (FEV1) was 53.35% ± 21.22 of the expected value (CI 95%: 49.76 - 56.94). The mean number of comorbidities presented by the patients was 2.51 ± 1.81 (CI 95%: 2.25 - 2.76) and the average number of drugs the patients were taking for COPD was 2.83 ± 1.24 drugs (IC95%: 2.66 - 3.01). Conclusion This study reveals a complex population, with moderate to severe COPD and a high burden of comorbidities. Thereby, it becomes clear that pulmonologists must consider the COPD patient as a whole due to the high prevalence of factors that can worsen the prognosis in this population.

The Incidence, Risk Factors, and Predictive Model of Obstructive Disease in Post-Tuberculosis Patients

Objective

To assess the incidence and risk factors of tuberculosis-associated obstructive pulmonary disease (TOPD) in individuals with treatment-naive pulmonary tuberculosis (PTB) and develop a predictive model to enhance its management.

Methods

The incidence of TOPD among patients with treatment-naive PTB in Xinjiang, China, was followed up for one year. Patient characteristics, such as demographics, medical histories, laboratory test results, lung radiological evidence, and pulmonary function, were collected upon hospital admission and throughout follow-up visits. Risk factors associated with TOPD were evaluated by multivariate logistic regression analysis, and then a predictive model was established using LASSO regression.

Results

Of the 159 included patients, 69 (43.4%) developed TOPD during the follow-up period. Multivariate regression analysis identified age, body mass index, ESR, and symptom duration as significant risk factors. Subsequently, a model formula was derived from these factors to predict TOPD. Utilizing a cut-off value of 0.435, the model demonstrated a sensitivity of 89% and a specificity of 83%.

Conclusion

In Xinjiang, the prevalence of TOPD appears notably high among treatment-naive PTB patients. Our findings, such as the risk factors and predictive model, may facilitate the early detection and improved interventions for TOPD among patients with PTB, potentially leading to better patient outcomes.

Comorbidities and Treatment Outcomes in Patients Diagnosed with Drug-Resistant Tuberculosis in Rural Eastern Cape Province, South Africa

BACKGROUND/OBJECTIVES

Tuberculosis (TB) remains a significant global health challenge, with drug-resistant tuberculosis (DR-TB) posing a greater threat due to difficulty in treatment. This study aimed to investigate the relationship between comorbidities and treatment outcomes in patients diagnosed with DR-TB in rural Eastern Cape using logistic regression.

METHODS

Data on patient characteristics, comorbidities, and treatment outcomes were extracted from the medical records and analyzed using Python version 3.8. and R version 4.1.1 software. A logistic regression model was used to determine the effects of selected variables on treatment outcomes of DR-TB cases.

RESULTS

Hearing loss and hypertension (HTN) were the most frequently observed comorbidities across various DR-TB cases, particularly rifampicin-resistant (RR), multidrug-resistant (MDR), and pre-extensively drug-resistant (pre-XDR-TB) cases. A hearing loss prevalence of 5.8% (26/445) was found among patients receiving treatment for TB, with the intensity of impairment ranging from mild to severe. Gender is significantly associated with the occurrence of HTN among these patients (p-value: 0.022). Comorbidities such as epilepsy, hearing loss, and HTN significantly impact treatment success, with higher risks of mortality and incomplete cure. Using logistic regression, obesity (OR = 3.0884; e = 1.1277; p = 0.0408) and HIV-positive status (OR = 0.4458; e = 0.8078; p = 0.0001) were highly likely and less likely associated with better treatment outcomes, respectively. The logistic regression model achieved an accuracy of 64.0%, a precision of 63.0%, and a recall of 95.0%, with an F-1 score of 76.0%.

CONCLUSIONS

The findings underscore the importance of implementing integrated management strategies that address both DR-TB and its comorbidities, particularly in resource-limited settings where such patients are prevalent. Public health policies should incorporate strategies to provide nutritional assessments and interventions, particularly for individuals with low BMI. This could include food supplementation programs or partnerships with local food kitchens to ensure that patients have access to adequate nutrition during DR-TB treatment.

Characteristics of Pulmonary Inflammation in Patients with Different Forms of Active Tuberculosis

Targeted treatment of tuberculosis-associated lung damage requires an understanding of the precise mechanisms of immunopathology. A major obstacle to the longitudinal study of tuberculosis (TB) immunopathogenesis in humans is the lack of serial lung biopsies during disease progression and treatment, which could be used to characterize local immune pathways involved in tissue damage. Understanding of the immunobiology of lung tissue damage in tuberculosis has largely been based on animal models. Our study looked for signs of inflammation in TB patients' lung biopsies. Results were compared between a site of infection and relatively healthy tissue outside the site. The most significant differences in the expression of microRNAs (miRs) and cytokine/chemokines were observed between the non-decayed tuberculoma and the surrounding parenchyma. In addition, these parameters showed almost no differences between the cavitary wall and surrounding tissue. This is an indication that the inflammatory process is more prevalent in fibrotic cavitary tuberculosis (FCT). In FCT subjects, no difference was observed between the cavity wall and the parenchyma in the production of key inflammatory factors such as IL-6, IL-11, IL-17, and IFNγ. This is an indication that the limits of the inflammatory response are broader in FCT. The expression levels of miR-191, miR-193a, miR-222, miR-223, miR-18, miR-155, miR-376c, miR-26a, miR-150, and miR-124 were not significantly different between the cavernous wall and lung tissue in patients with FCT, further confirming the spread of inflammatory and destructive processes beyond the focus of infection.

Mortality Rates after Tuberculosis Treatment, Georgia, USA, 2008-2019

Limited data exist on mortality rates after tuberculosis (TB) treatment in the United States. We analyzed mortality rates for all adults in Georgia, USA, who had a TB diagnosis and finished treatment during January 1, 2008-December 31, 2019. We obtained posttreatment mortality rate data from the National Death Index and calculated standardized mortality ratios (SMRs) for TB treatment survivors and the general Georgia population. Among 3,182 TB treatment survivors, 233 (7.3%) had died as of December 31, 2019. The overall TB cohort age- and sex-adjusted SMR was 0.89 (95% CI 0.73-1.05). The SMR among US-born TB treatment survivors was 1.56 (95% CI 1.36-1.77). In the TB cohort, US-born status, HIV co-infection, excess alcohol use, diabetes mellitus, and end-stage renal disease were associated with increased risk for death after TB treatment. TB treatment survivors could benefit from improved linkage to primary and HIV comprehensive care to prevent posttreatment death.

Impact of post-pulmonary tuberculosis sequelae and its management in a tertiary care facility in South India

BACKGROUND

Post-pulmonary Tuberculosis (PTB) sequelae are chest alterations caused by pulmonary tuberculosis problems, even after treatment and infection elimination. These alterations can cause pulmonary dysfunction, ranging from mild irregularities to acute dyspnea, increasing the risk of respiratory-related deaths. Current research aims to investigate the type, severity, clinical management, and impact on quality of life in affected individuals.

MATERIALS AND METHODS

A prospective observational study with 66 patients was carried out in a South Indian tertiary care facility. We gathered sociodemographic and clinical data from the patients. Imaging investigations (chest X-ray, CT scans) and pulmonary function test reports (Spirometry) were used to assess the post-pulmonary TB sequelae. The patient's quality of life was evaluated using the WHOQoL-BREF questionnaire.

RESULTS

Out of 66 patients, 66.7% were men, and the average age was 57.2 years. According to radiological analysis, most patients had airway difficulties (38%), followed by parenchymal problems (36.3%). Obstruction was the most typical abnormality identified (81.9%). Bronchodilators, LABA + ICS, SABA, leukotriene antagonists, antibiotics, and other fixed medications treat post-PTB sequelae. Substantial impairment was observed in quality of life.

CONCLUSION

Patients who have had pulmonary TB are prone to post-TB respiratory symptoms and sequelae. The quality of life noticeably declined. This study's findings underscore the importance of robust, evidence-based guidelines and practical implementation techniques for managing post-pulmonary TB.

Characterization of non-tuberculous mycobacterial pulmonary disease and pulmonary tuberculosis in patients with AFB smear-positive sputum: A retrospective comparative study

Background

Distinguishing nontuberculous mycobacteria pulmonary disease (NTM-PD) from pulmonary tuberculosis (PTB) is a challenge especially in patients with positive sputum smear of acid-fast bacilli (AFB). This study aimed to compare and identify the clinical characteristics between the two diseases among patients with positive sputum AFB.

Methods

From February 2017 through March 2021, patients with positive sputum AFB were reviewed in two hospitals of China. Among them, clinical data of NTM-PD and PTB patients was collected and compared.

Results

76 cases of NTM-PD and 92 cases of PTB were included in our study. When compared with PTB, NTM-PD patients were older (59.2 ± 11.4 vs 44.2 ± 19.5 years, P < 0.001) and manifested more hemoptysis and dyspnea (28.9 % vs 14.1 %, P < 0.05; 48.7 % vs 17.4 %, P < 0.001 respectively). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) for Xpert were 85.9 %, 96.1 %, 96.3 %, 84.9 %, respectively, compared to 94.2 %, 81.1 %, 83.1 %, 93.5 %, respectively for T-spot in diagnosing PTB. In radiological features, NTM-PD affected more lobes (4.53 ± 0.89 vs 3.61 ± 1.41, P < 0.001) and showed more consolidation (50 % vs 32.6 %, P < 0.05), destroyed lung (22.7 % vs 9.8 %, P < 0.05), honeycomb lung (26.7 % vs 6.5 %, P < 0.001) but less nodules (80.3 % vs 95.7 %, P < 0.05), tree-in-bud sign (49.3 % vs 87 %, P < 0.001), and satellite nodules (14.5 % vs 90.2 %, P < 0.001) than PTB. Age (odds ratio [OR], 1.043; 95 % confidence interval [CI], 1.018-1.069, P < 0.05), hemoptysis (OR, 3.552; 95%CI, 1.421-8.729, P < 0.05), and dyspnea (OR, 2.631; 95%CI, 1.151-6.016, P < 0.05) were independently correlated with NTM infection.

Conclusions

NTM-PD and PTB share similar clinical manifestations. Among them, advanced age, hemoptysis, and dyspnea are the independent predictors for NTM infection. Xpert is an efficiency analysis in discriminating between NTM-PD and PTB in patients with positive sputum AFB.

Tuberculosis-Associated Respiratory Disability in Children, Adolescents, and Adults: Protocol for a Systematic Review and Individual Participant Data Meta-Analysis

Background

Approximately 2% of the global population has survived tuberculosis (TB). Increasing evidence indicates that a significant proportion of pulmonary TB survivors develop TB-associated respiratory disability, commonly referred to as post-TB lung disease (PLTD) and marked by impaired respiratory function, persistent symptoms, and activity limitations. However, the prevalence, risk factors, and progression of TB-associated respiratory disability throughout the life course are not well understood. To address these gaps, we will undertake a systematic review and individual participant-level data meta-analysis (IPD-MA) focusing on TB-associated respiratory disability in children, adolescents, and adults successfully treated for pulmonary TB.

Methods and analysis

We will systematically search MEDLINE, Embase, CENTRAL, Global Index Medicus, and medRxiv for original studies investigating TB-associated respiratory disability in people of all ages who have completed treatment for microbiologically confirmed or clinically diagnosed pulmonary TB. Authors of eligible studies will be invited to contribute de-identified data and form a collaborative group. Primary outcomes will be (1) abnormal lung function based on spirometry parameters and (2) chronic respiratory symptoms. We will estimate the overall and subgroup-specific prevalence of each outcome through IPD meta-analysis. Next, we will develop clinical prediction tools assessing the risk of future TB-associated respiratory disability at (i) the start of TB treatment and (ii) end of TB treatment for those without existing signs of disability. Finally, we will use stepwise hierarchical modelling to identify epidemiological determinants of respiratory disability.

Ethics and dissemination

This study has been approved by the ethics review boards at the Rhode Island Hospital (2138217-2) and the Research Institute of the McGill University Health Centre (2024-10345). Individual study authors will be required to obtain institutional approval prior to sharing data. Results will be disseminated through open-access, peer-reviewed publications and conference presentations.

Prospero registration number

CRD42024529906.

Prevalence of non-communicable diseases among household contacts of people with tuberculosis: A systematic review and individual participant data meta-analysis

OBJECTIVE

To investigate the prevalence of non-communicable diseases among household contacts of people with tuberculosis.

METHODS

We conducted a systematic review and individual participant data meta-analysis. We searched Medline, Embase and the Global Index Medicus from inception to 16 May 2023. We included studies that assessed for at least one non-communicable disease among household contacts of people with clinical tuberculosis. We estimated the non-communicable disease prevalence through mixed effects logistic regression for studies providing individual participant data, and compared it with estimates from aggregated data meta-analyses. Furthermore, we compared age and sex-standardised non-communicable disease prevalence with national-level estimates standardised for age and sex.

RESULTS

We identified 39 eligible studies, of which 14 provided individual participant data (29,194 contacts). Of the remaining 25 studies, 18 studies reported aggregated data suitable for aggregated data meta-analysis. In individual participant data analysis, the pooled prevalence of diabetes in studies that undertook biochemical testing was 8.8% (95% confidence interval [CI], 5.1%-14.9%, four studies). Age-and sex-standardised prevalence was higher in two studies (10.4% vs. 6.9% and 11.5% vs. 8.4%) than the corresponding national estimates and similar in two studies. Prevalence of diabetes mellitus based on self-report or medical records was 3.4% (95% CI 2.6%-4.6%, 14 studies). Prevalence did not significantly differ compared to estimates from aggregated data meta-analysis. There were limited data for other non-communicable diseases.

CONCLUSION

The prevalence of diabetes mellitus among household contacts was high while that of known diabetes was substantially lower, suggesting the underdiagnosis. tuberculosis household contact investigation offers opportunities to deliver multifaceted interventions to identify tuberculosis infection and disease, screen for non-communicable diseases and address shared risk factors.

Audit of risk factors of drug-sensitive, drug-resistant tuberculosis disease, a case-control study of patients registered under NTEP, Gujarat

Background

Characterizing risk factors for drug-resistant tuberculosis (TB) is critical to guide targeted interventions in high-burden settings like India. We aimed to identify socioeconomic, lifestyle, and clinical factors associated with drug-sensitive and drug-resistant TB acquisition.

Materials and Methods

A comparative cross-sectional study recruited 350 bacteriologically confirmed TB patients registered under the National Tuberculosis Elimination Program (NTEP) in Gujarat, India, and 300 matched participants without active/past TB. Multinomial logistic regression analyzed risk factors for 200 drug-sensitive and 150 drug-resistant TB cases compared to participants without active or past TB.

Results

Key factors independently associated with higher adjusted odds ratios (aOR) of both TB types included low socioeconomic status (SES) (drug-sensitive TB: aOR 1.7, 95% CI 1.2-2.5; drug-resistant TB: aOR 2.2, 95% CI 1.3-3.7), crowding (>5 persons/room) (drug-sensitive TB: aOR 1.6, 95% CI 1.1-2.3; drug-resistant TB: aOR 1.9, 95% CI 1.2-2.9), undernutrition (drug-sensitive TB: aOR 1.6, 95% CI 1.1-2.3; drug-resistant TB: aOR 2.0, 95% CI 1.2-3.2), smoking (drug-sensitive TB: aOR 1.5, 95% CI 1.0-2.3; drug-resistant TB: aOR 1.7, 95% CI 1.1-2.7), and indoor air pollution (drug-sensitive TB: aOR 1.5, 95% CI 1.0-2.2; drug-resistant TB: aOR 1.8, 95% CI 1.2-2.8).

Conclusion

Marked social determinants and clinical risks drive heightened susceptibility for both TB types in India, while prior inadequate treatment and nosocomial exposures selectively enable additional drug resistance. Holistic prevention policies jointly targeting transmission, vulnerability, and curative factors are imperative.

ISCCM Position Statement on the Approach to and Management of Critically Ill Patients with Tuberculosis

Tuberculosis (TB) is an important cause of morbidity and mortality globally. About 3-4% of hospitalized TB patients require admission to the intensive care unit (ICU); the mortality in these patients is around 50-60%. There is limited literature on the evaluation and management of patients with TB who required ICU admission. The Indian Society of Critical Care Medicine (ISCCM) constituted a working group to develop a position paper that provides recommendations on the various aspects of TB in the ICU setting based on available evidence. Seven domains were identified including the categorization of TB in the critically ill, diagnostic workup, drug therapy, TB in the immunocompromised host, organ support, infection control, and post-TB sequelae. Forty-one questions pertaining to these domains were identified and evidence-based position statements were generated, where available, keeping in focus the critical care aspects. Where evidence was not available, the recommendations were based on consensus. This position paper guides the approach to and management of critically ill patients with TB.

How to cite this article

Chacko B, Chaudhry D, Peter JV, Khilnani G, Saxena P, Sehgal IS, et al. isccm Position Statement on the Approach to and Management of Critically Ill Patients with Tuberculosis. Indian J Crit Care Med 2024;28(S2):S67-S91.

A mouse model of TB-associated lung fibrosis reveals persistent inflammatory macrophage populations during treatment

Post-TB lung disease (PTLD) causes a significant burden of global disease. Fibrosis is a central component of many clinical features of PTLD. To date, we have a limited understanding of the mechanisms of TB-associated fibrosis and how these mechanisms are similar to or dissimilar from other fibrotic lung pathologies. We have adapted a mouse model of TB infection to facilitate the mechanistic study of TB-associated lung fibrosis. We find that the morphologies of fibrosis that develop in the mouse model are similar to the morphologies of fibrosis observed in human tissue samples. Using Second Harmonic Generation (SHG) microscopy, we are able to quantify a major component of fibrosis, fibrillar collagen, over time and with treatment. Inflammatory macrophage subpopulations persist during treatment; matrix remodeling enzymes and inflammatory gene signatures remain elevated. Our mouse model suggests that there is a therapeutic window during which adjunctive therapies could change matrix remodeling or inflammatory drivers of tissue pathology to improve functional outcomes after treatment for TB infection.

Economic burden of chronic obstructive pulmonary disease and post-tuberculosis sequelae in low- and middle-income countries: a database compiled from a systematic review and meta-analysis

Background

Chronic obstructive pulmonary disease (COPD) and tuberculosis (TB) impose a substantial economic burden globally. This systematic review summarised the evidence on the costs of COPD, including post-TB diseases in low- and middle-income countries.

Methods

A systematic review was conducted and studies published between 1 January 2013 and 28 March 2022 (the date of the search) were identified using various electronic databases without language restrictions. Titles, abstracts and full texts were screened in duplicate and data were extracted and verified by reviewers. Eligible studies were categorised as cost analysis and/or economic burden studies, and costs were converted to 2021 United State dollar. Meta-analysis was conducted on the costs of hospitalisations, medication and outpatient visits.

Results

128 cost studies and 65 economic burden studies were included in this review. The data collected are presented in the Cost Database of COPD and Post-TB (CD-CPTB). The majority of studies were from Asia, Eastern Europe and Latin America, with a few from other middle-income countries. There were extremely limited data on the costs of post-TB sequelae and only a few studies were from Africa (n=6) and low-income (n=5) countries. The direct medical costs of COPD ranged from $26 per hospitalisation in India to $2694 per year per patient with severe disease in Mexico, while the costs of acute exacerbation of COPD ranged from $137 to $4207 per exacerbation with both the minimum and maximum costs occurring in Turkey. The costs were lower in lower middle-income countries compared with upper middle-income countries. Finally, considerable economic burden was attributable to smoking and air pollution.

Conclusion

The review and the CD-CPTB database give a thorough snapshot of the current evidence of the costs and economic burden of COPD and post-TB diseases. Future research is needed to investigate the economic impact after TB treatment and should be prioritised in Africa and low-income countries where there has been a lack of data collection.

Protocol registration number

CRD42022326609.

Trends in the Notification Rates and Treatment Outcome of Tuberculosis in Shandong Province, China, 2005-2021

Purpose

To analyze the time trends in the notification rates of registered tuberculosis (TB) and bacteriologically confirmed TB in Shandong Province. And analyze the changes in TB treatment outcomes during 2005-2021.

Patients and Methods

The information of TB patients registered in the Shandong Information Center for Disease Control and Prevention (CDC) was collected during 2005-2021. We calculated the notification rates of registered TB and bacteriologically confirmed TB. Moreover, we calculated the year-to-year change rate of TB in treatment outcomes before and after COVID-19. The time trends were analyzed using the joinpoint regression method and illustrated as the annual percentage change (APC) of notification rates.

Results

A total of 236,898 cases of TB were diagnosed during 2005-2021, of which 51.11% were bacteriologically confirmed cases. Since 2008, the notification rates of registered TB have declined. The notification rates of bacteriologically confirmed TB had been declining during 2005-2016, then remained stable after 2016. In subgroup, the notification rates of both registered TB and bacteriologically confirmed TB were higher among men, rural residents, and people aged ≥ 60 years. Compared with clinically confirmed TB, bacteriologically confirmed TB has shown higher rates of poor outcomes since 2008 and higher case fatality rate since 2005. The rate of poor outcomes remained stable during 2008-2019. However, after the COVID-19 outbreak, the rate of poor outcomes and case fatality rate of TB has risen significantly.

Conclusion

After unremitting efforts to fight against TB, the notification rates of registered TB and bacteriologically confirmed TB declined in Shandong Province. The rate of poor outcomes remained stable during 2008-2019, then rise significantly after the COVID-19 outbreak. In the context of the long-term existence of COVID-19, further efforts should be made in TB diagnosis and treatment among high-risk population, especially with regard to males, rural residents and older adults.

Fatal Nocardia paucivorans Lower Respiratory Tract Infection in a Tuberculosis Suspect Who Worked as Gold Miner

Nocardiosis is an opportunistic infection that affects both immunocompromised as well as immunocompetent patients. The main infections occur as soft tissue and lung infections although they might disseminate to various organs. This is a case study aimed to reflect the severity of the disease and the patient's risk factors associated with the infection. A sputum sample was collected from tuberculosis (TB) suspects for culture. Nocardia-like colonies were isolated, purified, and sent to BGI Company (Hongkong, China). Standard forward sequencing of 16S rRNA was done by ABI Genetic Analyzer (Applied Biosystems). Sequence alignment and nucleotide basic local alignment search tool (BLAST) were done using National Center for Bioinformatics (NCBI) Nucleotide BLAST. Biochemical identification to the colonies was done using an automation system (BD Phoenix™) to confirm the identification. Nocardia paucivorans was identified from the TB suspect. Risk factors were identified as extensive contact to dust, absence of primary care units with complete facilities, and old age. Since the infection of the lungs caused by Nocardia might be similar to pulmonary TB, this case report highlights the importance of accurate diagnosis and identification procedures to differentiate between the two.

Breath of fresh air: Investigating the link between AGEs, sRAGE, and lung diseases

Advanced glycation end products (AGEs) are compounds formed via non-enzymatic reactions between reducing sugars and amino acids or proteins. AGEs can accumulate in various tissues and organs and have been implicated in the development and progression of various diseases, including lung diseases. The receptor of advanced glycation end products (RAGE) is a receptor that can bind to advanced AGEs and induce several cellular processes such as inflammation and oxidative stress. Several studies have shown that both AGEs and RAGE play a role in the pathogenesis of lung diseases, such as chronic obstructive pulmonary disease, asthma, idiopathic pulmonary fibrosis, cystic fibrosis, and acute lung injury. Moreover, the soluble form of the receptor for advanced glycation end products (sRAGE) has demonstrated its ability to function as a decoy receptor, possessing beneficial characteristics such as anti-inflammatory, antioxidant, and anti-fibrotic properties. These qualities make it an encouraging focus for therapeutic intervention in managing pulmonary disorders. This review highlights the current understanding of the roles of AGEs and (s)RAGE in pulmonary diseases and their potential as biomarkers and therapeutic targets for preventing and treating these pathologies.

Associations between mixed exposure to phthalates and latent tuberculosis infection among the general U.S. population from NHANES 2011-2012

Background

People are constantly exposed to phthalates, but few reliable studies have focused on the connection between phthalate exposure and latent tuberculosis infection (LTBI).

Methods

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) database (2011-2012). The LTBI was assessed by QuantiFERON®-TB Gold-In-Tube (QFT) or tuberculin skin testing (TST). The odds ratios (ORs) and 95% confidence intervals (CIs) per log10 unit change in the concentration of phthalate metabolites were calculated using crude and adjusted logistic regression models. The relationships between mixed phthalate concentrations and LTBI were assessed using Bayesian kernel machine regression (BKMR) models.

Results

According to the results of the multivariable logistic regression, in a fully adjusted model, only monobenzyl phthalate (MBZP) was negatively associated with LTBI in Q3 (OR (95% CI): 0.485 (0.286,0.823), P = 0.007). According to the restricted cubic spline (RCS) model, there was a linear dose‒response association between all 11 phthalate metabolites and LTBI (p for nonlinearity >0.05). We found a significant positive correlation between mixed phthalate metabolites and LTBI by using fully adjusted BKMR model.

Conclusions

Our analysis demonstrated that LTBI in the general U.S. population is linearly linked with exposure to single or combined phthalates.

Increased Risk of Incident Chronic Obstructive Pulmonary Disease and Related Hospitalizations in Tuberculosis Survivors: A Population-Based Matched Cohort Study

BACKGROUND

Tuberculosis (TB) survivors have an increased risk of developing chronic obstructive pulmonary disease (COPD). This study assessed the risk of COPD development and COPD-related hospitalization in TB survivors compared to controls.

METHODS

We conducted a population-based cohort study of TB survivors and 1:1 age- and sex-matched controls using data from the Korean National Health Insurance Service database collected from 2010 to 2017. We compared the risk of COPD development and COPD-related hospitalization between TB survivors and controls.

RESULTS

Of the subjects, 9.6% developed COPD, and 2.8% experienced COPD-related hospitalization. TB survivors had significantly higher COPD incidence rates (36.7/1,000 vs. 18.8/1,000 person-years, P < 0.001) and COPD-related hospitalization (10.7/1,000 vs. 4.3/1,000 person-years, P < 0.001) than controls. Multivariable Cox regression analyses revealed higher risks of COPD development (adjusted hazard ratio [aHR], 1.63; 95% confidence interval [CI], 1.54-1.73) and COPD-related hospitalization (aHR, 2.03; 95% CI, 1.81-2.27) in TB survivors. Among those who developed COPD, the hospitalization rate was higher in individuals with post-TB COPD compared to those with non-TB COPD (10.7/1,000 vs. 4.9/1,000 person-years, P < 0.001), showing an increased risk of COPD-related hospitalization (aHR, 1.84; 95% CI, 1.17-2.92).

CONCLUSION

TB survivors had higher risks of incident COPD and COPD-related hospitalization compared to controls. These results suggest that previous TB is an important COPD etiology associated with COPD-related hospitalization.

Characteristics and phenotypes of a COPD cohort from referral hospital clinics in Uganda

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a heterogeneous condition with varied clinical and pathophysiological characteristics. Although there is increasing evidence that COPD in low-income and middle-income countries may have different clinical characteristics from that in high-income countries, little is known about COPD phenotypes in these settings. We describe the clinical characteristics and risk factor profile of a COPD population in Uganda.

METHODS

We cross sectionally analysed the baseline clinical characteristics of 323 patients with COPD aged 30 years and above who were attending 2 national referral outpatient facilities in Kampala, Uganda between July 2019 and March 2021. Logistic regression was used to determine factors associated with spirometric disease severity.

RESULTS

The median age was 62 years; 51.1% females; 93.5% scored COPD Assessment Test >10; 63.8% modified medical research council (mMRC) >2; 71.8% had wheezing; 16.7% HIV positive; 20.4% had a history of pulmonary tuberculosis (TB); 50% with blood eosinophilic count >3%, 51.7% had 3 or more exacerbations in the past year. Greater severity by Global initiative for Chronic Obstructive Lung Disease (GOLD) stage was inversely related to age (aOR=0.95, 95% CI 0.92 to 0.97), and obesity compared with underweight (aOR=0.25, 95% CI 0.07 to 0.82). Regarding clinical factors, more severe airflow obstruction was associated with SPO2 <93% (aOR=3.79, 95% CI 2.05 to 7.00), mMRC ≥2 (aOR=2.21, 95% CI 1.08 to 4.53), and a history of severe exacerbations (aOR=2.64, 95% CI 1.32 to 5.26).

CONCLUSION

Patients with COPD in this population had specific characteristics and risk factor profiles including HIV and TB meriting tailored preventative approaches. Further studies are needed to better understand the pathophysiological mechanisms at play and the therapeutic implications of these findings.

Ageing and disease risk factors: A new paleoepidemiological methodology for understanding disease in the past

OBJECTIVES

To outline a methodology that enables the reconstruction of age-related disease risk in past societies.

MATERIALS

Modern epidemiological evidence considering risk factors for age-related disease is combined with contextual information about an archaeological society of interest.

METHODS

Data gathered is used to create a qualitative population-specific risk model for the disease of interest. To provide a case study, a risk model is constructed for Chronic Obstructive Pulmonary Disease (COPD) in the Eastern English Bronze Age.

RESULTS

This enables the first rigorous approach to reconstructing age-related disease risk in the past. A risk model shows a high degree of COPD risk in the Eastern English Bronze Age, with a major contribution from indoor airborne pollution and agricultural practices.

SIGNIFICANCE

This represents a significant new approach in human paleopathology, facilitating understanding of the occurrence of a wide variety of diseases in the past, without the need for well-preserved skeletons of identified elderly individuals.

LIMITATIONS

The risk models generated are, of necessity, qualitative rather than quantitative, since we are unable to calculate the size of risk factors in the past with certainty.

SUGGESTIONS FOR FURTHER RESEARCH

The methodology could be applied to a wide variety of diseases and for many past societies.

Chronic Pulmonary Aspergillosis as a Considerable Complication in Post-Tuberculosis Lung Disease

Post-tuberculosis lung disease (PTLD) has only recently been put in the spotlight as a medical entity. Recent data suggest that up to 50% of tuberculosis (TB) patients are left with PTLD-related impairment after completion of TB treatment. The presence of residual cavities in the lung is the largest risk factor for the development of chronic pulmonary aspergillosis (CPA) globally. Diagnosis of CPA is based on four criteria including a typical radiological pattern, evidence of Aspergillus species, exclusion of alternative diagnosis, and a chronic course of disease. In this manuscript, we provide a narrative review on CPA as a serious complication for patients with PTLD.

Dextran-based Drug Delivery Approaches for Lung Diseases: A Review

Respiratory disorders, such as tuberculosis, cystic fibrosis, chronic obstructive pulmonary disease, asthma, lung cancer, and pulmonary inflammation, are among the most prevalent ailments in today's world. Dextran, an exopolysaccharide formed by Leuconostoc mesenteroides (slimeproducing bacteria), and its derivatives are investigated for several therapeutic utilities. Dextranbased drug delivery system can become an innovative strategy in the treatment of several respiratory ailments as it offers numerous advantages, such as mucolytic action, airway hydration, antiinflammatory properties, and radioprotective effect as compared to other polysaccharides. Being biocompatible, flexible hydrophilic nature, biodegradable, tasteless, odourless, non-mutagenic, watersoluble and non-toxic edible polymer, dextran-based drug delivery systems have been explored for a wide range of therapeutic applications, especially in lungs and respiratory diseases. The present article comprehensively discusses various derivatives of dextran with their attributes to be considered for drug delivery and extensive therapeutic benefits, with a special emphasis on the armamentarium of dextran-based formulations for the treatment of respiratory disorders and associated pathological conditions. The information provided will act as a platform for formulation scientists as important considerations in designing therapeutic approaches for lung and respiratory diseases. With an emphasis on lung illnesses, this article will offer an in-depth understanding of dextran-based delivery systems in respiratory illnesses.

Factors associated with mortality in HIV-TB co-infected patients during and after the course of TB treatment in high-burden settings, Mumbai, India: A cohort analysis

BACKGROUND

Knowledge of factors associated with TB mortality during treatment and post treatment will help us develop better monitoring and implementation strategies for TB control. We designed the present study to examine the factors associated with mortality in HIV-TB co-infected patients during and after the course of TB treatment.

METHODS

This study is a cohort analysis of secondary data collected from 1804 HIV-TB co-infected individuals from 16 anti-retroviral therapy (ART) centres affiliated with the Mumbai Districts AIDS Control Society, Mumbai, India. We used Kaplan Meier survival curves and hazard ratios to estimate the mortality in patients.

RESULTS

The overall mortality rate in this cohort was 1.14 per 100 per month. The mortality proportion was 18% (95% CI: 16.1%, 20.1%) during treatment and 10.6% (95% CI: 8.9%, 12.5%) in the post-treatment period. Mortality was significantly higher in those with a CD4 count 0-200 cells/mm3 (HR: 3.04, 95% CI: 2.13, 4.15; p < 0.001), and in patients who were ART naïve and referred to the ART centre with a diagnosis of TB (HR: 1.39, 95% CI: 1.06, 1.82; p = 0.016). Mortality was also significantly higher in the first 6 months after initiation of ART (HR: 1.36, 95% CI: 1.06, 1.75; p = 0.016). A decrease in the CD4 counts from initial levels at start of TB treatment to end of TB treatment was associated with higher mortality in the post-treatment period.

DISCUSSION

The overall mortality remains high; early identification of TB and HIV disease, and use of rapid point of care tests for diagnosis of TB are needed across all health care facilities. Post-treatment follow-up and monitoring is important in HIV-TB co-infected patients, and post-treatment mortality should also be considered as one of the indicators for successful TB control programmes.

Tuberculosis and Risk of Emphysema among US Adults in the NHANES I Epidemiologic Follow-Up Study Cohort, 1971-1992

(1) Background: History of TB is a known risk factor for long-term respiratory impairment affecting lung functions in both restrictive and obstructive lung disease. (2) Methods: We analyzed data from the NHANES I Epidemiologic Follow-up Study (NHEFS), a longitudinal study conducted on a noninstitutionalized adult US population aged 25-74 years. Approximately 93 percent of the original NHANES I cohort was successfully traced by the end of the survey period and was available for analysis. The final adjusted model included age groups, gender, family income, lifetime smoking, body mass index (BMI), and frequency of alcohol consumption as potential confounders. (3) Results: The estimated hazards ratio of developing emphysema during follow-up for individuals with a past diagnosis of TB was 54% lower (95% CI = 0.35, 0.61) that that in individuals with no past TB, after controlling for potential confounders and using proportional hazards regression appropriate to the complex sample design. The association, however, was not statistically significant (HR = 0.86, p-value = 0.38) when only a self-reported history of TB was considered as the exposure in an unadjusted model. (4) Conclusions: Tuberculosis (self-reported or LTBI) was strongly (but inversely) associated with emphysema incidence. The association was not statistically significant with only a self-reported history of TB as exposure.

Prevalence of mental distress in adults with and without a history of tuberculosis in an urban Zambian community

People with tuberculosis (TB) are susceptible to mental distress. Mental distress can be driven by biological and socio-economic factors including poverty. These factors can persist beyond TB treatment completion yet there is minimal evidence about the mental health of TB survivors. A cross-sectional TB prevalence survey of adults was conducted in an urban community in Zambia. Survey participants were administered the five-item Self Reporting Questionnaire (SRQ-5) mental health screening tool to measure mental distress. Associations between primary exposure (history of TB) and other co-variates with mental distress were investigated using logistic regression. Of 3,393 study participants, 120 were TB survivors (3.5%). The overall prevalence of mental distress (SRQ-5 ≥ 4) in the whole study population was 16.9% (95% CI 15.6%-18.1%). Previous TB history was not associated with mental distress (OR 1.20, 95% CI 0.75-1.92, p-value 1.66). Mental distress was associated with being female (OR 1.23 95% CI 1.00-1.51), older age (OR 1.71 95% CI 1.09-2.68) and alcohol abuse (OR 1.81 95% CI 1.19-2.76). Our findings show no association between a previous TB history and mental distress. However, approximately one in six people in the study population screened positive for mental distress.

Identification and validation of ubiquitination-related signature and subgroups in immune microenvironment of tuberculosis

BACKGROUND

Mycobacterium tuberculosis (Mtb) is the bacterial pathogen responsible for causing tuberculosis (TB), a severe public health concern that results in numerous deaths worldwide. Ubiquitination (Ub) is an essential physiological process that aids in maintaining homeostasis and contributes to the development of TB. Therefore, the main objective of our study was to investigate the potential role of Ub-related genes in TB.

METHODS

Our research entailed utilizing single sample gene set enrichment analysis (ssGSEA) in combination with several machine learning techniques to discern the Ub-related signature of TB and identify potential diagnostic markers that distinguish TB from healthy controls (HC).

RESULTS

In summary, we used the ssGSEA algorithm to determine the score of Ub families (E1, E2, E3, DUB, UBD, and ULD). Notably, the score of E1, E3, and UBD were lower in TB patients than in HC individuals, and we identified 96 Ub-related differentially expressed genes (UbDEGs). Employing machine learning algorithms, we identified 11 Ub-related hub genes and defined two distinct Ub-related subclusters. Notably, through GSVA and functional analysis, it was determined that these subclusters were implicated in numerous immune-related processes. We further investigated these Ub-related hub genes in four TB-related diseases and found that TRIM68 exhibited higher correlations with various immune cells in different conditions, indicating that it may play a crucial role in the immune process of these diseases.

CONCLUSION

The observed enrichment of Ub-related gene expression in TB patients emphasizes the potential involvement of ubiquitination in the progression of TB. These significant findings establish a basis for future investigations to elucidate the molecular mechanisms associated with TB, select suitable diagnostic biomarkers, and design innovative therapeutic interventions for combating this fatal infectious disease.

Risk factors and biomarkers for post-tuberculosis lung damage in a Chinese cohort of male smokers and non-smokers: protocol for a prospective observational study

INTRODUCTION

Post-tuberculosis lung damage (PTLD) refers to the residual pulmonary impairment following the completion of antituberculosis (TB) therapy, characterised by persistent respiratory symptoms and abnormal pulmonary function. The risk factors and biomarkers for PTLD have been scarcely investigated. More importantly, whether and to what extent cigarette smoking is involved in PTLD remain to be known.

METHODS AND ANALYSIS

This prospective observational study will enrol 400 male smoking or non-smoking patients aged 25-65 years, with newly confirmed active TB between 2022 and 2024, from the Department of Respiratory and Critical Care Medicine at Peking University Third Hospital and the Tuberculosis Department at Beijing Geriatric Hospital. Because females rarely smoke in China, we will enrol only males in this study. Demographic data, smoking history and amount, clinical symptoms, lung function, and chest CT findings will be prospectively collected. Respiratory questionnaires, lung function measurements and chest CT examinations will be performed immediately after, and 1 year, 2 years and 3 years after the completion of TB treatment. Peripheral blood samples will be obtained at baseline and at the end of anti-TB therapy, and a Luminex xMAP-based multiplex immunoassay will be used to measure inflammatory mediators and cytokines in serum. The collected data will be analysed to determine the incidence and factors/biomarkers of PTLD according to smoking status.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee of Peking University Third Hospital (approval number: (2022)271-03; approval date: 8 June 2022). The research results will be disseminated through scientific and medical conferences and will be published in an academic journal.

TRIAL REGISTRATION NUMBER

NCT04966052.

Distinct healthcare utilization profiles of high healthcare use tuberculosis survivors: A latent class analysis

BACKGROUND

Recent data have demonstrated that healthcare use after treatment for respiratory tuberculosis (TB) remains elevated in the years following treatment completion. However, it remains unclear which TB survivors are high healthcare users and whether any variation exists within this population. Thus, the primary objective of this study was to identify distinct profiles of high healthcare-use TB survivors to help inform post-treatment support and care.

METHODS

Using linked health administrative data from British Columbia, Canada, we identified foreign-born individuals who completed treatment for incident respiratory TB between 1990 and 2019. We defined high healthcare-use TB survivors as those in the top 10% of annual emergency department visits, hospital admissions, or general practitioner visits among the study population during the five-year period immediately following TB treatment completion. We then used latent class analysis to categorize the identified high healthcare-use TB survivors into subgroups.

RESULTS

Of the 1,240 people who completed treatment for respiratory TB, 258 (20.8%) people were identified as high post- TB healthcare users. Latent class analysis results in a 2-class solution. Class 1 (n = 196; 76.0%) included older individuals (median age 71.0; IQR 59.8, 79.0) with a higher probability of pre-existing hypertension and diabetes (41.3% and 33.2%, respectively). Class 2 (n = 62; 24.0%) comprised of younger individuals (median age 31.0; IQR 27.0, 41.0) with a high probability (61.3%) of immigrating to Canada within five years of their TB diagnosis and a low probability (11.3%) of moderate to high continuity of primary care.

DISCUSSION

Our findings suggest that foreign-born high healthcare-use TB survivors in a high-resource setting may be categorized into distinct profiles to help guide the development of person-centred care strategies targeting the long-term health impacts TB survivors face.

Healthcare Utilization After Respiratory Tuberculosis: A Controlled Interrupted Time Series Analysis

BACKGROUND

Despite data suggesting elevated morbidity and mortality among people who have survived tuberculosis disease, the impact of respiratory tuberculosis on healthcare utilization in the years following diagnosis and treatment remains unclear.

METHODS

Using linked health administrative data from British Columbia, Canada, we identified foreign-born individuals treated for respiratory tuberculosis between 1990 and 2019. We matched each person with up to four people without a tuberculosis diagnosis from the same source cohort using propensity score matching. Then, using a controlled interrupted time series analysis, we measured outpatient physician encounters and inpatient hospital admissions in the 5 years following respiratory tuberculosis diagnosis and treatment.

RESULTS

We matched 1216 individuals treated for respiratory tuberculosis to 4864 non-tuberculosis controls. Immediately following the tuberculosis diagnostic and treatment period, the monthly rate of outpatient encounters in the tuberculosis group was 34.0% (95% confidence interval [CI]: 30.7%, 37.2%) higher than expected, and this trend was sustained for the duration of the post-tuberculosis period. The excess utilization represented an additional 12.2 (95% CI: 10.6, 14.9) outpatient encounters per person over the post-tuberculosis period, with respiratory morbidity a large contributor to the excess healthcare utilization. Results were similar for hospital admissions, with an additional 0.4 (95% CI: .3, .5) hospital admissions per person over the post-tuberculosis period.

CONCLUSIONS

Respiratory tuberculosis appears to have long-term impacts on healthcare utilization beyond treatment. These findings underscore the need for screening, assessment, and treatment of post-tuberculosis sequelae, as it may provide an opportunity to improve health and reduce resource use.

The epidemiological characteristics and infection risk factors for extrapulmonary tuberculosis in patients hospitalized with pulmonary tuberculosis infection in China from 2017 to 2021

BACKGROUND

Pulmonary tuberculosis (PTB) complicated with extrapulmonary tuberculosis (EPTB) infection can aggravate the disease, but there have been few reports.

METHODS

Retrospective analysis was used to collect the clinical data of PTB patients with pathogen positive in a teaching hospital from 2017 to 2021. We describe the incidence, the invasive site of EPTB patients, and analyze the infection risk factors for PTB with EPTB by univariate and multivariate logistic regression models. We also compared the complications, disease burden with chi-square test and rank-sum test.

RESULTS

A total of 1806 PTB were included, of which 263 (14.6%) were complicated with EPTB. The common invasive sites for EPTB were neck lymph nodes (16.49%), intestines (16.13%), and meninges (10.75%). Age ≤ 40 (OR = 1.735; 95%CI [1.267-2.376]; P = 0.001), malnutrition (OR = 2.029; 95%CI [1.097-3.753]; P = 0.022), anemia (OR = 1.739; 95%CI[1.127-2.683]; P = 0.012), and osteoporosis (OR = 4.147; 95%CI [1.577-10.905]; P = 0.004) were all independent risk factors for PTB infection with EPTB. The incidence of extrathoracic hydrothorax, intestinal bacterial infection, urinary tract bacterial infection, and abdominal bacterial infection were higher in patients with PTB with EPTB. PTB with EPTB patients also had longer median hospitalization durations (19 vs. 14 days), during which time they incurred higher total costs, laboratory test costs, imaging examination costs, and drug use costs.

CONCLUSION

This study found important risk factors for PTB complicated with EPTB, such as age ≤ 40, malnutrition, anemia, and osteoporosis. PTB with EPTB patients have more extrapulmonary complications and higher hospitalization disease burden.

Using a theory-informed approach to guide the initial development of a post-tuberculosis care package in British Columbia, Canada

BACKGROUND

The importance of addressing the long-term needs of tuberculosis (TB) survivors is gaining increasing attention. One promising approach to improving post-TB care is implementing a post-TB care package. With a specific focus on the perspectives of healthcare providers in British Columbia, Canada, this study aimed to (1) determine a set of components to be included in a post-TB care package, (2) explore barriers and facilitators influencing their implementation, and (3) propose potential solutions to overcome identified challenges.

METHODS

Employing a multi-method approach guided by the Theoretical Domains Framework, we first conducted virtual workshops with TB care providers and utilized a modified Delphi process to establish a preliminary list of care package components. Then, we surveyed healthcare providers using closed-ended, Likert-scale questions to identify implementation barriers and enablers. Lastly, we mapped the identified barriers and enablers to establish behaviour change techniques to identify possible solutions to overcome the challenges identified.

RESULTS

Eleven participants attended virtual workshops, and 23 of 51 (45.1%) healthcare providers completed questionnaires. Identified components of the post-TB care package included: 1. Linking people with TB to a primary care provider if they do not have one. 2. Referring people with pulmonary TB for an end-of-treatment chest x-ray and pulmonary function testing. 3. Referring people with TB who smoke to a smoking cessation specialist. 4. Sharing a one-page post-TB information sheet with the patient's primary care provider, including a summary of post-TB health concerns, complications, and recommendations to prioritize age-appropriate screening for cardiovascular disease, lung cancer, and depression. Survey results indicated that domain scores for 'environment, context, and resources' were the lowest, suggesting potential implementation barriers. Care navigation services to help individuals overcome health system barriers while transitioning from TB care, information leaflets, and checklists summarizing key post-TB health concerns for patients and healthcare providers to help facilitate discussions may help overcome the identified barriers.

CONCLUSION

Healthcare providers in British Columbia acknowledge that post-TB care is integral to comprehensive health care but are limited by time and resources. Care navigation services, a post-TB checklist, and patient information leaflets may help resolve some of these barriers.

Retreatment after loss to follow-up reduces mortality in patients with multidrug/rifampicin-resistant tuberculosis

Background

This study evaluated the risk factors of long-term mortality in patients with multidrug/rifampicin-resistant tuberculosis (MDR/RR-TB) in South Korea who were lost to follow-up (LTFU).

Methods

This was a retrospective longitudinal follow-up study using an integrated database constructed by data linkage of the three national databases, which included 7226 cases of MDR/RR-TB notified between 2011 and 2017 in South Korea. Post-treatment outcomes of patients who were LTFU were compared with those of patients who achieved treatment success.

Results

Of the 7226 MDR/RR-TB cases, 730 (10.1%) were LTFU. During a median follow-up period of 4.2 years, 101 (13.8%) of the LTFU patients died: 25 deaths (3.4%) were TB related and 76 (10.4%) were non-TB related. In the LTFU group, the adjusted hazard ratio (aHR) of all-cause mortality (aHR 2.50, 95% CI 1.99-3.15, p<0.001), TB-related mortality (aHR 5.38, 95% CI 3.19-9.09, p<0.001) and non-TB-related mortality (HR 2.21, 95% CI 1.70-2.87, p<0.001) was significantly higher than that in the treatment success group. Independent risk factors for all-cause mortality in the LTFU group were age >55 years, fluoroquinolone resistance, cancer and no retreatment. In the LTFU patients who did not receive retreatment, the risk of non-TB-related mortality (aHR 5.00, 95% CI 1.53-16.37, p=0.008) and consequent all-cause mortality (aHR 2.18, 95% CI 1.08-4.40, p=0.030) was significantly higher than that of patients who received retreatment.

Conclusion

Non-TB-related mortality was the main cause of death and might be reduced by retreatment in LTFU patients with MDR/RR-TB.

Tuberculosis in older adults: challenges and best practices in the Western Pacific Region

The Western Pacific has one of the fastest-growing older adult populations globally, and tuberculosis (TB) remains one of the foremost infectious causes of disease and death in the region. Older adults are at higher risk of TB due to immunosenescence, comorbidities, and increased institutionalisation. Atypical symptoms and reduced access to health services may delay care-seeking and TB diagnosis, while co-morbidity and increased risk of adverse drug reactions complicate TB treatment. Post-TB sequelae and socioeconomic challenges may decrease the quality of life after TB treatment completion. Despite their high disease burden and special challenges, there is a lack of regionally coordinated policies and guidelines to manage TB among older adults. Routine TB screening at aged-care facilities, age-friendly infrastructure and services, awareness of atypical TB features, integration of TB and non-communicable diseases services, and person-centred approaches to treatment support could improve TB management among older adults. Addressing these challenges and adopting the best practices identified should inform policy formulation and implementation.

Funding

This project was funded by 1) the World Health Organization Regional Office for the Western Pacific, with financial contributions from the Government of the Republic of Korea through the Korean Disease Control and Prevention Agency and the Government of Japan through the Ministry of Health, Labour and Welfare, and 2) NUS Start-up Grant. The funders had no role in the paper design, collection, analysis, and interpretation of data and in writing of the paper.

Post-tuberculosis lung impairment: systematic review and meta-analysis of spirometry data from 14 621 people

BACKGROUND

A substantial proportion of tuberculosis patients remain with pulmonary symptoms and reduced physical capacity despite successful treatment. We performed a systematic review to analyse the burden of post-tuberculosis lung impairment measured by lung function testing.

METHODS

We searched the PubMed database for articles published between database inception and November 2020 and performed meta-analyses to estimate the prevalence, type and severity of lung impairment among drug-susceptible and multidrug-resistant tuberculosis survivors. Methodological quality of included studies was assessed using the Newcastle-Ottawa scale.

RESULTS

54 articles were included in this review. For subjects with former drug-susceptible tuberculosis, the combined estimated mean was 76.6% (95% CI 71.6-81.6) of predicted for forced expiratory volume in 1 s (FEV1) and 81.8% (95% CI 77.4-86.2) for forced vital capacity (FVC). In former patients with multidrug-resistant tuberculosis, it was 65.9% (95% CI 57.1-74.7) for FEV1 and 76.0% (95% CI 66.3-85.8) for FVC, respectively. The analysis of impairment types in former patients with drug-susceptible and multidrug-resistant tuberculosis showed that 22.0% versus 19.0% had obstructive, 23.0% versus 22.0% restrictive and 15.0% versus 43.0% had mixed impairment type, respectively. In the majority of studies, at least 10-15% of tuberculosis survivors had severe lung impairment.

CONCLUSIONS

This systematic review showed long-term abnormal spirometry results in a significant proportion of tuberculosis survivors.

Mechanisms of lung damage in tuberculosis: implications for chronic obstructive pulmonary disease

Pulmonary tuberculosis is increasingly recognized as a risk factor for COPD. Severe lung function impairment has been reported in post-TB patients. Despite increasing evidence to support the association between TB and COPD, only a few studies describe the immunological basis of COPD among TB patients following successful treatment completion. In this review, we draw on well-elaborated Mycobacterium tuberculosis-induced immune mechanisms in the lungs to highlight shared mechanisms for COPD pathogenesis in the setting of tuberculosis disease. We further examine how such mechanisms could be exploited to guide COPD therapeutics.

Cross-sectional validation of the COPD Assessment Test (CAT) among chronic obstructive pulmonary disease patients in rural Uganda

Measuring quality of life is a key component in the management of Chronic Obstructive Pulmonary Disease (COPD). The COPD assessment test (CAT), an easy to administer and shorter instrument than the standard Saint George's respiratory questionnaire (SGRQ), could be an alternative tool for measuring the quality of life of COPD patients in rural Uganda. A cross-sectional study was conducted between June and August 2022, consecutively recruiting 113 COPD patients aged > 40 years from the Low-Dose Theophylline for the management of Biomass-associated COPD (LODOT-BCOPD) study. Upon obtaining consent, participants answered an interviewer administered social demographic, CAT and SGRQ questionnaire. Internal consistency for both SGRQ and CAT was determined using Cronbach's alpha coefficient and values > 0.7 were considered acceptable while correlations were determined using Spearman's rank correlation. Limits of Agreement were visualised using Bland Altman and pair plots. Of the 113 participants, 51 (45.1%) were female. The mean age was 64 ± 12 years, 19 (16.8%) had history of smoking while majority (112 (99.1%)) reported use of firewood for cooking. There was a strong correlation of 0.791 (p < 0.001) between the CAT and SGRQ total scores with a high internal consistency of CAT, Cronbach's alpha coefficient of 0.924 (0.901-0.946). The agreement between the absolute CAT scores and the SGRQ scores was good with a mean difference of -0.932 (95% Confidence Interval: -33.49-31.62). In summary, CAT has an acceptable validity and can be used as an alternative to the SGRQ to assess the quality of life of COPD patients in rural Uganda.

CR. Burden of Chronic Obstructive Pulmonary Disease Attributable to Tuberculosis: A Microsimulation Study

Tuberculosis (TB) is a risk factor for chronic obstructive pulmonary disease (COPD), but COPD is also a predictor of TB. The excess life-years lost to COPD caused by TB can potentially be saved by screening for and treating TB infection. We examined the number of life-years that could be saved by preventing TB and TB-attributable COPD. We compared the observed (no intervention) and counterfactual microsimulation models constructed from observed rates in the Danish National Patient Registry (covering all Danish hospitals between 1995 and 2014). In the Danish population of TB and COPD-naive individuals (n = 5,206,922), 27,783 persons (0.5%) developed TB. Among those who developed TB, 14,438 (52.0%) developed TB with COPD. Preventing TB saved 186,469 life-years overall. The excess number of life-years lost to TB alone was 7.07 years per person, and the additional number of life-years lost among persons who developed COPD after TB was 4.86 years per person. The life-years lost to TB-associated COPD are substantial, even in regions where TB can be expected to be identified and treated promptly. Prevention of TB could prevent a substantial amount of COPD-related morbidity; the benefit of screening and treatment for TB infection is underestimated by considering morbidity from TB alone.