Pulmonary tuberculosis treated with directly observed therapy: serial changes in lung structure and function

Quality by Design in Pulmonary Drug Delivery: A Review on Dry Powder Inhaler Development, Nanotherapy Approaches, and Regulatory Considerations

Dry powder inhalers (DPIs) are state-of-the-art pulmonary drug delivery systems. This article explores the transformative impact of nanotechnology on DPIs, emphasizing the Quality Target Product Profile (QTPP) with a focus on aerodynamic performance and particle characteristics. It navigates global regulatory frameworks, underscoring the need for safety and efficacy standards. Additionally, it highlights the emerging field of nanoparticulate dry powder inhalers, showcasing their potential to enhance targeted drug delivery in respiratory medicine. This concise overview is a valuable resource for researchers, physicians, and pharmaceutical developers, providing insights into the development and commercialization of advanced inhalation systems.

Unveiling Silent Consequences: Impact of Pulmonary Tuberculosis on Lung Health and Functional Wellbeing after Treatment

Background: Pulmonary tuberculosis (TB) remains a major public health issue in India, with high incidence and mortality. The current literature on post-TB sequelae functional defects focuses heavily on spirometry, with conflicting obstruction vs. restriction data, lacks advanced statistical analysis, and has insufficient data on diffusion limitation and functional impairment. Objective: This study aimed to thoroughly evaluate post-tubercular sequelae after treatment, assessing chest radiology, spirometry, diffusing capacity, and exercise capacity. Methods: A total of 85 patients were studied at a university teaching hospital in Mysuru. The data collected included characteristics, comorbidities, smoking history, and respiratory symptoms. The investigations included spirometry, DLCO, chest X-rays with scoring, and 6MWT. Results: Of the patients, 70% had abnormal X-rays post-treatment, correlating with reduced lung function. Additionally, 70% had impaired spirometry with obstructive/restrictive patterns, and 62.2% had reduced DLCO, with females at higher risk. Smoking increased the risk of sequelae. Conclusions: Most patients had residual radiological/lung function abnormalities post-treatment. Advanced analyses provide insights into obstructive vs. restrictive defects. Ongoing research should explore pathogenetic mechanisms and therapeutic modalities to minimize long-term post-TB disability.

COVID-19 and Comorbidities: What Has Been Unveiled by Metabolomics?

The COVID-19 pandemic has brought about diverse impacts on the global population. Individuals with comorbidities were more susceptible to the severe symptoms caused by the virus. Within the crisis scenario, metabolomics represents a potential area of science capable of providing relevant information for understanding the metabolic pathways associated with the intricate interaction between the viral disease and previous comorbidities. This work aims to provide a comprehensive description of the scientific production pertaining to metabolomics within the specific context of COVID-19 and comorbidities, while highlighting promising areas for exploration by those interested in the subject. In this review, we highlighted the studies of metabolomics that indicated a variety of metabolites associated with comorbidities and COVID-19. Furthermore, we observed that the understanding of the metabolic processes involved between comorbidities and COVID-19 is limited due to the urgent need to report disease outcomes in individuals with comorbidities. The overlap of two or more comorbidities associated with the severity of COVID-19 hinders the comprehension of the significance of each condition. Most identified studies are observational, with a restricted number of patients, due to challenges in sample collection amidst the emergent situation.

Post-tuberculosis lung disease and inflammatory role players: can we characterise the myriad inflammatory pathways involved to gain a better understanding?

Tuberculosis (TB) remains a global health threat, and even after successful TB treatment, a subset of patients develops serious long-term lung impairments, recently termed post-tuberculosis lung disease (PTLD). Much remains to be discovered, as PTLD as a post-TB disease is a developing field, still in its infancy. The pathogenesis of PTLD is not fully elucidated but has been linked to elevated inflammatory pathways. The complexity of PTLD makes it challenging to pinpoint the specific inflammatory pathways involved in its pathophysiology. Therefore, this paper provides a comprehensive review of inflammatory cytokines and their potential roles in PLTD, with a specific focus on interleukin 6 (IL-6), IL-1, IL-8, tumour necrosis factor-alpha (TNF-α), transforming growth factor beta (TGF-β) and C-Reactive Protein (CRP). We delve into PTLD pathology, discuss its impact on lung function and review risk factors for PTLD. In addition, we summarise the current gaps in knowledge, provide recommendations for measuring inflammatory biomarkers and propose potential directions for future studies. We propose that future studies measure a wide range of inflammatory markers in TB populations with and without PTLD. In addition, studies could isolate peripheral blood mononuclear cells from patient blood to try and identify possible impairments that could be correlated with a PTLD diagnosis. Given that the PTLD field is still in an early stage of development, a comprehensive inflammatory analysis may help to know which pathways are key in PTLD development, and this may ultimately help to predict patients who are at risk. More research is warranted.

Long term management of people with post-tuberculosis lung disease

Post-tuberculosis lung disease (PTLD) is emerging as a significant area of global interest. As the number of patients surviving tuberculosis (TB) increases, the subsequent long-term repercussions have drawn increased attention due to their profound clinical and socioeconomic impacts. A primary obstacle to its comprehensive study has been its marked heterogeneity. The disease presents a spectrum of clinical manifestations which encompass tracheobronchial stenosis, bronchiectasis, granulomas with fibrosis, cavitation with associated aspergillosis, chronic pleural diseases, and small airway diseases-all persistent consequences of PTLD. The spectrum of symptoms a patient may experience varies based on the severity of the initial infection and the efficacy of the treatment received. As a result, the long-term management of PTLD necessitates a detailed and specific approach, addressing each manifestation individually-a tailored strategy. In the immediate aftermath (0-12 months after anti-TB chemotherapy), there should be an emphasis on monitoring for relapse, tracheobronchial stenosis, and smoking cessation. Subsequent management should focus on addressing hemoptysis, managing infection including aspergillosis, and TB-associated chronic obstructive pulmonary disease or restrictive lung function. There remains a vast expanse of knowledge to be discovered in PTLD. This review emphasizes the pressing need for comprehensive, consolidated guidelines for management of patients with PTLD.

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.

Surviving Pulmonary Tuberculosis: Navigating the Long Term Respiratory Effects

Tuberculosis is a transmissible disease caused by the bacteria Mycobacterium tuberculosis, which is a cause of significant morbidity and mortality all over the world. Tuberculosis has a number of risk factors, such as living in a developing country, poor ventilation, smoking, male sex, etc., which not only increase the chance of infection but may be independent factors for impairment in pulmonary function as well. In this review article, we have compiled several studies to learn how tuberculosis causes impaired lung function and further explored the long-term effects of tuberculosis on the same. We studied tuberculosis's effect on the lungs even after appropriate treatment and its relationship with obstructive and restrictive lung disorders. A significant relationship exists between chronic respiratory disorders and tuberculosis even after treatment; hence, we believe prevention is far superior to cure.

Impaired pulmonary function and associated factors in the elderly with tuberculosis on admission: a preliminary report

BACKGROUND

Pulmonary tuberculosis (TB) can impair pulmonary function (PF), especially in the elderly. The risk factors associated with the severity of PF impairment in the elderly with pulmonary TB remain unclear. Hence, this retrospective study aimed to address this issue to help improve the management of TB in the elderly population.

METHODS

From January 2019 to February 2022, the elderly who were admitted to our hospital for pulmonary TB and underwent PF testing were included in this analysis. The forced expiratory volume in one second percent of predicted (FEV1% predicted) and clinical characteristics were collected and analyzed retrospectively. The extent of impaired PF was then categorized based on the FEV1% predicted and classified as grade 1-5. Logistic regression analysis was used to analyze the risk factors for impaired PF.

RESULTS

A total of 249 patients who met the enrollment criteria were included in this analysis. According to the results of FEV1% predicted, all patients were classified as grade 1 (n = 37), grade 2 (n = 46), grade 3 (n = 55), grade 4 (n = 56), or grade 5 (n = 55). Statistical analysis showed that albumin (adjusted odds ratio (aOR) = 0.928, P = 0.013), body mass index (BMI) < 18.5 kg/m² (aOR = 4.968, P = 0.046), lesion number ≥ 3 (aOR = 4.229, P < 0.001), male (aOR = 2.252, P = 0.009), respiratory disease (aOR = 1.669, P = 0.046), and cardiovascular disease (aOR = 2.489, P = 0.027) were related to the impairment of PF.

CONCLUSIONS

PF impairment is common in the elderly with pulmonary TB. The male sex, BMI < 18.5 kg/m², lesion number ≥ 3, hypoproteinemia, and respiratory and cardiovascular comorbidities were identified as risk factors for significant PF impairment. Our findings highlight the risk factors associated with PF impairment, which may be helpful to improve the current management of pulmonary TB in the elderly to save their lung function.

Inflammation-mediated tissue damage in pulmonary tuberculosis and host-directed therapeutic strategies

Treatment of tuberculosis (TB) involves the administration of anti-mycobacterial drugs for several months. The emergence of drug-resistant strains of Mycobacterium tuberculosis (Mtb, the causative agent) together with increased disease severity in people with co-morbidities such as diabetes mellitus and HIV have hampered efforts to reduce case fatality. In severe disease, TB pathology is largely attributable to over-exuberant host immune responses targeted at controlling bacterial replication. Non-resolving inflammation driven by host pro-inflammatory mediators in response to high bacterial load leads to pulmonary pathology including cavitation and fibrosis. The need to improve clinical outcomes and reduce treatment times has led to a two-pronged approach involving the development of novel antimicrobials as well as host-directed therapies (HDT) that favourably modulate immune responses to Mtb. HDT strategies incorporate aspects of immune modulation aimed at downregulating non-productive inflammatory responses and augmenting antimicrobial effector mechanisms to minimise pulmonary pathology and accelerate symptom resolution. HDT in combination with existing antimycobacterial agents offers a potentially promising strategy to improve the long-term outcome for TB patients. In this review, we describe components of the host immune response that contribute to inflammation and tissue damage in pulmonary TB, including cytokines, matrix metalloproteinases, lipid mediators, and neutrophil extracellular traps. We then proceed to review HDT directed at these pathways.

A comparison of the chest radiographic and computed tomographic features of subclinical pulmonary tuberculosis

Subclinical pulmonary tuberculosis (PTB) is a recently described intermediate state of great interest, but about which little is known. This study sought to describe and compare the frequency of key radiologic features of subclinical PTB on chest radiograph (CXR) versus computed tomographic scan (CT), and to interpret the clinical and public health relevance of the differences. Diagnostic CXRs and CT scans of the thorax and neck in a 16-year cohort of subclinical PTB patients in Canada were re-acquired and read by two independent readers and arbitrated by a third reader. Logistic regression models were fit to determine how likely CXR features can be detected by CT scan versus CXR after adjustment for age and sex. Among 296 subclinical patients, CXRs were available in 286 (96.6%) and CT scans in 94 (32.9%). CXR features in patients with and without CT scans were comparable. Lung cavitation was 4.77 times (95% CI 1.95–11.66), endobronchial spread 19.36 times (95% CI 8.05–46.52), and moderate/far-advanced parenchymal disease 3.23 times (95% CI 1.66–6.30), more common on CT scan than CXR. We conclude that the extent to which CXRs under-detect key radiologic features in subclinical PTB is substantial. This may have public health and treatment implications.

Pulmonary function in cured pulmonary tuberculosis cases

BACKGROUND

In clinical practice it has been observed that several patients of cured pulmonary tuberculosis (PTB) suffer with lung dysfunction and these problems are less documented routinely. Prevalence of these abnormalities remains unknown. Aim of this study is to estimate the lung function abnormality and exercise capacity including diffusion capacity of lung for carbon monoxide (DLCO) in cured PTB cases.

METHODS

A hospital based observational descriptive study was carried out among 100 patients with PTB, who had been declared cured. These patients were evaluated by spirometry and DLCO to assess their lung function and were classified as normal or abnormal. Modified medical research council (mMRC) dyspnea scale for symptom assessment and 6-minute walk test (6MWT) to determine the exercise capacity was also done. Borg's scale was used for dyspnea assessment in 6MWT.

RESULTS

83 (83%) patients having abnormal spirometry, 17 (17%) had obstructive pattern, 32 (32%) had restrictive pattern and 34 (34%) had mixed pattern. 22 (22%) patients had mild decrease in DLCO, 43 (43%) patients had moderate decrease in DLCO, while only 4 (4%) had severe decrease in DLCO. More than half of the patients having normal spirometry had reduced in DLCO.

CONCLUSION

The prevalence of abnormal lung functions is high even after complete anti-tubercular treatment. DLCO could be a better tool for evaluation of lung function in these patients. There is need to strengthen the National Programme to detect and treat TB patient earlier, also there is need to formulate guidelines for pulmonary rehabilitation of cured PTB patient.

A scoring system developed from a nomogram to differentiate active pulmonary tuberculosis from inactive pulmonary tuberculosis

Purpose

This study aimed to develop and validate a scoring system based on a nomogram of common clinical metrics to discriminate between active pulmonary tuberculosis (APTB) and inactive pulmonary tuberculosis (IPTB).

Patients and methods

A total of 1096 patients with pulmonary tuberculosis (PTB) admitted to Wuhan Jinyintan Hospital between January 2017 and December 2019 were included in this study. Of these patients with PTB, 744 were included in the training cohort (70%; 458 patients with APTB, and 286 patients with IPTB), and 352 were included in the validation cohort (30%; 220 patients with APTB, and 132 patients with IPTB). Data from 744 patients from the training cohort were used to establish the diagnostic model. Routine blood examination indices and biochemical indicators were collected to construct a diagnostic model using the nomogram, which was then transformed into a scoring system. Furthermore, data from 352 patients from the validation cohort were used to validate the scoring system.

Results

Six variables were selected to construct the prediction model. In the scoring system, the mean corpuscular volume, erythrocyte sedimentation rate, albumin level, adenosine deaminase level, monocyte-to-high-density lipoprotein ratio, and high-sensitivity C-reactive protein-to-lymphocyte ratio were 6, 4, 7, 5, 5, and 10, respectively. When the cut-off value was 15.5, the scoring system for recognizing APTB and IPTB exhibited excellent diagnostic performance. The area under the curve, specificity, and sensitivity of the training cohort were 0.919, 84.06%, and 86.36%, respectively, whereas those of the validation cohort were 0.900, 82.73, and 86.36%, respectively.

Conclusion

This study successfully constructed a scoring system for distinguishing APTB from IPTB that performed well.

Identification of Prognostic Metabolomic Biomarkers at the Interface of Mortality and Morbidity in Pre-Existing TB Cases Infected With SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection currently remains one of the biggest global challenges that can lead to acute respiratory distress syndrome (CARDS) in severe cases. In line with this, prior pulmonary tuberculosis (TB) is a risk factor for long-term respiratory impairment. Post-TB lung dysfunction often goes unrecognized, despite its relatively high prevalence and its association with reduced quality of life. In this study, we used a metabolomics analysis to identify potential biomarkers that aid in the prognosis of COVID-19 morbidity and mortality in post-TB infected patients. This analysis involved blood samples from 155 SARS-CoV-2 infected adults, of which 23 had a previous diagnosis of TB (post-TB), while 132 did not have a prior or current TB infection. Our analysis indicated that the vast majority (~92%) of post-TB individuals showed severe SARS-CoV-2 infection, required intensive oxygen support with a significantly high mortality rate (52.2%). Amongst individuals with severe COVID-19 symptoms, we report a significant decline in the levels of amino acids, notably the branched chains amino acids (BCAAs), more so in the post-TB cohort (FDR <= 0.05) in comparison to mild and asymptomatic cases. Indeed, we identified betaine and BCAAs as potential prognostic metabolic biomarkers of severity and mortality, respectively, in COVID-19 patients who have been exposed to TB. Moreover, we identified serum alanine as an important metabolite at the interface of severity and mortality. Hence, our data associated COVID-19 mortality and morbidity with a long-term metabolically driven consequence of TB infection. In summary, our study provides evidence for a higher mortality rate among COVID-19 infection patients who have history of prior TB infection diagnosis, which mandates validation in larger population cohorts.

Neutrophils Contribute to Severity of Tuberculosis Pathology and Recovery From Lung Damage Pre- and Posttreatment

BACKGROUND

Despite microbiological cure, about 50% of tuberculosis (TB) patients have poor lung recovery. Neutrophils are associated with lung pathology; however, CD16/CD62L-defined subsets have not been studied in TB. Using flow cytometry, we monitored frequencies, phenotype, and function of neutrophils following stimulation with Mycobacterium tuberculosis (Mtb) whole cell lysate (WCL) and ESAT-6/CFP-10 fusion protein (EC) in relation to lung pathology.

METHODS

Fresh blood from 42 adult, human immunodeficiency virus (HIV)-negative TB patients were analyzed pre- and post-therapy, with disease severity determined using chest radiography and bacterial load. Flow cytometry was used to monitor frequencies, phenotype, and function (generation of reactive oxygen species [ROS], together with CD11b, tumor necrosis factor, and interleukin 10 [IL-10] expression) of neutrophils following 2-hour stimulation with Mtb-specific antigens.

RESULTS

Total neutrophils decreased by post-treatment compared to baseline (P = .0059); however, CD16brCD62Lbr (segmented) neutrophils increased (P = .0031) and CD16dimCD62Lbr (banded) neutrophils decreased (P = .038). Banded neutrophils were lower in patients with severe lung damage at baseline (P = .035). Following WCL stimulation, ROS from segmented neutrophils was higher in patients with low Mtb loads even after adjusting for sex (P = .038), whereas IL-10-expressing CD16dimCD62Llo cells were higher in patients with mild damage (P = .0397) at baseline.

CONCLUSIONS

High ROS generation, low levels of banded neutrophils, and high levels of IL-10-expressing CD16dimCD62Llo neutrophils are associated with reduced lung pathology at diagnosis. Hence, neutrophils are potential early indicators of TB severity and promising targets for TB host-directed therapy.

Association of serum MMP-9 level and lung function in new pulmonary tuberculosis case

Background:

Histopathological abnormalities of pulmonary tuberculosis (TB) include caseous granuloma formation, tissue damage, and cavity formation, all of which could lead to permanent changes in the pulmonary anatomy. In pulmonary TB, an increase in serum Matrix Metalloproteinase (MMP)-9 correlates with disease severity and worse prognosis. This study aims to analyze the association between serum MMP-9 levels and the values of FVC, FEV1, and FEV1/FVC.

Methods:

A cross-sectional study of patients with pulmonary tuberculosis was conducted in the Tuberculosis Outpatient Clinic, Dr. Soetomo Academic Hospital, Surabaya, Indonesia. Spirometry and serum MMP-9 levels were examined in new pulmonary TB patients prior to anti-tuberculosis therapy. The relationship between serum MMP-9 levels and results of spirometry examination was then analyzed.

Results:

There were 44 new pulmonary TB cases with a mean age of 37.90 ± 15.15 years. The patients who experienced symptoms in < 1 month were 20.5%, ≥ 1 month 59.1%, and ≥ 2 months 20.4%. The mean MMP-9 serum level was 11.27±5.47 ng/ml. Spirometry results: FVC 1.83±0.69 L, FVC predicted 56.24±18.74%, FEV1 1.71±0.72 L/sec, FEV1 predicted 60.85±21.30%, and FEV1/FVC 104.16 ± 17.45%. In pulmonary TB patients with symptoms experienced in < 1 month to diagnosis, a significant relationship between MMP-9 and FVC levels was found with r = -0.839 (p = 0.005).

Conclusion:

There is a correlation between serum MMP-9 level and restrictive pulmonary impairment in new pulmonary TB cases with symptoms experienced in < 1 month.

Structural and functional pulmonary impairment in treated cases of pulmonary tuberculosis: a cross-sectional study

Background

Pulmonary impairment after tuberculosis treatment is seen in 40%-75% of patients despite bacteriological cure. Study aimed to find prevalence of structural and functional pulmonary impairment in a group of previously fit serving soldiers at the end of supervised institutional treatment for pulmonary tuberculosis.

Methods

Descriptive cross-sectional study was conducted in a tertiary care center on 375 newly diagnosed patients of pulmonary tuberculosis completed treatment. They underwent spirometry and chest X ray (CXR) at end of treatment. Their lung function was classified as normal or abnormal (obstructive, restrictive, or mixed pattern). Chest radiographs were reported as normal/abnormal. Logistic regression models were used to explore the factors associated with abnormal lung function.

Results

Functional impairment was present in 145/375 (38.7%). 115/375 (30.66%) had restrictive, 24/375 (6.4%) had mixed, and 6/375 (1.6%) had obstructive pattern on spirometry, respectively. Out of the 115 patients having restrictive pattern, 103 (89.56%) had mild restriction, 11(9.56%) had moderate restriction, and 1 (0.86%) had severe restriction. Structural impairment on CXR was present in 309/375 (82.4%) of patients. Significant factors associated with pulmonary impairment in our study were time to diagnosis (>1 month) adj odds ratio (OR) = 1.71, 95% confidence interval (CI) 1.07-2.74, sputum conversion of >2 months, Adj OR 2.52, 95% CI 1.25-5.07, and sputum/culture positivity Adj OR 1.57, 95% CI 1.02-2.42. CXR abnormality was significantly associated with sputum and/culture positivity Adj OR 4.54, 95% CI 2.28-9.03.

Conclusion

Despite successful treatment, pulmonary impairment was present in 38.7% of patients, and structural changes evident on CXR was present in 82.4% of patients.

Efficacy of early structured pulmonary rehabilitation program in pulmonary function, exercise capacity, and health-related quality of life for patients with post-tubercular sequelae: A pilot study

Background

Residual structural changes in the lung along with pulmonary impairment remain in a large number of patients of tuberculosis after microbiological cure. The aim of this study was to determine whether 12 weeks of a structured pulmonary rehabilitation program (PRP) administered along with antitubercular treatment improved the baseline measurement of pulmonary function, exercise capacity, and health-related quality of life (HRQOL).

Methods

A pilot study with single blind randomized control design was carried out in a tertiary care chest center. Spirometry, exercise capacity by 6-minute walk distance (6MWD), and HRQOL using St George respiratory questionnaire (SGRQ) score were evaluated in 62 patients, divided into 2 groups: intervention group (IG) (n = 31) and control group (CG) (n = 31) patients at baseline and at end of 12 weeks. IG completed 12 weeks of PRP.

Results

Significant difference in forced expiratory volume in 1st second (FEV1) (2.94 L at baseline vs 3.18 L at end of 12 weeks of PRP, diff 0.239 L, p-0.001), forced vital capacity (FVC) (3.43 L vs 3.75L, p -0.00), 6MWD (440.6 m vs 574.6 m, p = 0.00), and SGRQ score of at baseline (24.5 m vs 11.1m, p = 0.00) was seen in the IG. At end of 12 weeks, there was statistically significant difference in FEV1(L) (p = 0.01, 95% CI -0.317 to -0.046), FVC(L) (p = 0.00, 95% CI -0.359 to -0.139),6MWD(m) (p = 0.00; 95% CI -101.6 to -49.57) between CG and IG. There was no statistically significant difference in SGRQ scores between the 2 groups (p = 0.231).

Conclusion

PRP administered along with treatment is beneficial in reducing residual pulmonary impairment.

All trans retinoic acid as a host-directed immunotherapy for tuberculosis

Tuberculosis (TB) is the top bacterial infectious disease killer and one of the top ten causes of death worldwide. The emergence of strains of multiple drug-resistant tuberculosis (MDR-TB) has pushed our available stock of anti-TB agents to the limit of effectiveness. This has increased the urgent need to develop novel treatment strategies using currently available resources. An adjunctive, host-directed therapy (HDT) designed to act on the host, instead of the bacteria, by boosting the host immune response through activation of intracellular pathways could be the answer. The integration of multidisciplinary approaches of repurposing currently FDA-approved drugs, with a targeted drug-delivery platform is a very promising option to reduce the long timeline associated with the approval of new drugs - time that cannot be afforded given the current levels of morbidity and mortality associated with TB infection. The deficiency of vitamin A has been reported to be highly associated with the increased susceptibility of TB. All trans retinoic acid (ATRA), the active metabolite of vitamin A, has proven to be very efficacious against TB both in vitro and in vivo. In this review, we discuss and summarise the importance of vitamin A metabolites in the fight against TB and what is known regarding the molecular mechanisms of ATRA as a host-directed therapy for TB including its effect on macrophages cytokine profile and cellular pathways. Furthermore, we focus on the issues behind why previous clinical trials with vitamin A supplementation have failed, and how these issues might be overcome.

The clinical and functional characteristics of bronchiectasis among tuberculosis patients in Upper Egypt: a single-center study

Background

Tuberculosis (TB) is considered one of the most common causes of bronchiectasis. Bronchiectasis increases clinical and financial burden of patients with TB. Here, we aim to assess the prevalence of bronchiectasis and its characteristics in patients with TB.

Results

Over 1 year duration, 85 patients with confirmed TB were enrolled in the study. Those patients were clinically, laboratory, and radiologically evaluated. Any patient with other chest diseases was excluded from the study. Out of those patients, 19/85 (22.4%) patients had bronchiectasis. It was found that patients with bronchiectasis had higher frequency of urban residence, current cigarette or goza smoking, and diabetes mellitus. Hemoptysis and expectoration were the most frequent symptoms. Pulmonary function tests were significantly impaired in patients with bronchiectasis. Disease burden was significantly higher among bronchiectasis group in form of frequent hospitalization, longer hospital stay, and need of oxygen therapy.

Conclusion

Bronchiectasis is not uncommon among TB patients. Co-existence of bronchiectasis with TB has distinctive clinical, and functional characteristics that increase the burden of the diseases in the form of prolonged hospital stay and higher utilization of antibiotics and oxygen therapy. Smoking in tuberculous patients may is significantly associated with bronchiectasis.

Correlations Between Inflammatory Biomarkers in Tuberculosis-Associated Obstructive Pulmonary Disease Patients With Anxiety and Depression

Introduction

Tuberculosis-associated obstructive pulmonary disease (TOPD), anxiety, and depression are significant public health problems worldwide and their prevalence is common. These diseases interfere with physical, psychosocial, and economic well-being, resulting in unemployment, prolonged hospitalization, abstinence from working, and isolation.

Subjects and methods

This is a single-center, cross-sectional cohort, observational study conducted in a tertiary care hospital over six years to understand spirometry, laboratory profiles, as well as the impact on overall health, daily life, and perceived well-being in patients with TOPD.

Result

The sample size of the study was 73 patients. A total of 43 (58.5%) patients had depression with an average St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease (SGRQ-C) score of 67.5, and 16 (21.9%) patients had anxiety with an average SGRQ-C score of 78.9. In the patients who scored higher on the Hamilton Depression Rating Scale (HAM-D), there was a significant correlation between Hamilton Anxiety Rating Scale (HAM-A) and HAM-D scores, as well as C-reactive protein (CRP) levels and WBC counts. In 16 (21.9%) of the patients with moderate to severe anxiety, there was a statistically significant negative correlation between higher HAM-A scores and lower WBC counts. Anxiety, depression, CRP level, WBC count, and serum fibrinogen did not show a significant correlation with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) groups-based assessment of TOPD severity. A high serum fibrinogen level did not correlate with a high HAM-D score, nor did a high CRP level correlate with a high HAM-A score.

Conclusion

Psychiatric comorbidities like depression are associated with increased inflammation in chronic diseases like TOPD, but no definitive biomarker has been identified and further studies are required to identify suitable biomarkers.

Evaluation of radiological sequelae after treatment completion in new cases of pulmonary and pleural tuberculosis

Background

The objective of this study was to evaluate the residual parenchymal and pleural lesions on chest X-ray posttherapy in new tuberculosis (TB) cases.

Methods

This prospective study was done from January 2018 to December 2020, which involved the evaluation of medical records of 60 pulmonary or pleural TB patients who underwent successful treatment. Chest X-rays of the patients at the start and end of treatment were studied as per the guidelines by Revised National Tuberculosis Control Program. The primary outcome measures were residual chest X-ray lesions after the complete treatment of new cases of TB. Secondary outcomes measures were significant factors affecting the chest X-ray clearance.

Results

Chest X-ray showed clearing in 48.33% of cases. Residual chest X-ray findings were present in 31 cases which mainly included fibrosis in 23.33% and pleural thickening in 20%. None of the clinical and demographic characters and biochemical parameters showed significant association with chest X-ray clearance (P > 0.05). Sputum microscopy was done in 45 cases of which 25 (41.66%) were positive for acid-fast bacilli. Sputum positivity showed no significant correlation with chest X-ray clearance (odds ratio [OR]: 0.734, confidence interval [CI]: 0.224-2.411, P = 0.592). Compared to nonstandardized regimen, standardized regimen showed no significant correlation with chest X-ray clearance (OR: 0.664; CI: 0.233-1.892, P = 0.426).

Conclusion

Residual radiological sequelae were seen in more than half of the study subjects who were successfully treated for TB (51.67%). Demographic, clinical characteristics, sputum positivity, and treatment regimen showed no significant association with chest X-ray clearance.

Deep Learning to Determine the Activity of Pulmonary Tuberculosis on Chest Radiographs

Background Determining the activity of pulmonary tuberculosis on chest radiographs is difficult. Purpose To develop a deep learning model to identify active pulmonary tuberculosis on chest radiographs. Materials and Methods Chest radiographs were retrospectively gathered from a multicenter consecutive cohort with pulmonary tuberculosis who were successfully treated between 2011 and 2017, along with normal radiographs to enrich a negative class. The pretreatment and posttreatment radiographs were labeled as positive and negative classes, respectively. A neural network was trained with those radiographs to calculate the probability of active versus healed tuberculosis. A single-center consecutive cohort (test set 1; 89 patients, 148 radiographs) and data from one multicenter randomized controlled trial (test set 2; 366 patients, 3774 radiographs) were used to test the model. The area under the receiver operating characteristic curve (AUC) was used to evaluate the performance of the model and of the four expert readers. Results In total, 6654 pre- and posttreatment radiographs from 3327 patients (mean age ± standard deviation, 55 years ± 19; 1884 men) with pulmonary tuberculosis and 3182 normal radiographs from as many patients (mean age, 53 years ± 14; 1629 men) were gathered. For test set 1, the model showed a higher AUC (0.83; 95% CI: 0.73, 0.89) than one pulmonologist (0.69; 95% CI: 0.61, 0.76; P < .001) and performed similarly to the other readers (AUC, 0.79-0.80; P = .14-.23). For 200 randomly selected radiographs from test set 2, the model had a higher AUC (0.84) than the pulmonologists (0.71 and 0.74; P < .001 and .01, respectively) and performed similarly to the radiologists (0.79 and 0.80; P = .08 and .06, respectively). The model output increased by 0.30 on average with a higher degree of smear positivity (95% CI: 0.20, 0.39; P < .001) and decreased during treatment (baseline, 3 months, and 6 months: 0.85, 0.51, and 0.26, respectively). Conclusion A deep learning model performed similarly to radiologists for accurately determining the activity of pulmonary tuberculosis on chest radiographs; it also was able to follow posttreatment changes. © RSNA, 2021 Online supplemental material is available for this article.

The Blood Neutrophil Count After 1 Month of Treatment Predicts the Radiologic Severity of Lung Disease at Treatment End

BACKGROUND

Lung disease after tuberculous confers significant morbidity. However, the determinants of persistent lung damage in TB are not well established. We investigated associations between TB-associated radiologic changes and sociodemographic factors, surrogates of bacillary burden, and blood inflammatory markers at initiation of therapy and after 1 month.

RESEARCH QUESTION

What are the predictors of radiologic severity at the end of TB treatment for TB?

STUDY DESIGN AND METHODS

We collected data from patients treated for drug-sensitive pulmonary TB at our center over a 5.5-year period. We recorded age, sex, ethnicity, smoking status, symptom duration, sputum smear grade, time to culture positivity, and blood results (C-reactive protein and neutrophil count) at baseline and after 1 month of treatment. Chest radiographs obtained at baseline, 2 months, and end of treatment were assessed independently by two radiologists and scored using a validated system. Relationships between predictor variables and radiologic outcomes were assessed using linear or binary logistic regression.

RESULTS

We assessed 154 individuals with a mean age of 37 years, 63% of whom were men. In a multivariate analysis, baseline radiologic severity correlated with sputum smear grade (P = 0.003) and neutrophil count (P < 0.001). At end of treatment, only the 1-month neutrophil count was associated significantly with overall radiologic severity in the multivariate analysis (r = 0.34; P = 0.003) and remained significant after controlling for baseline radiologic scores. The 1-month neutrophil count also was the only independent correlate of volume loss and pleural thickening at the end of treatment and was significantly higher in patients with persistent cavitation or effusion vs those without.

INTERPRETATION

Persistent neutrophilic inflammation after 1 month of TB therapy is associated with poor radiologic outcome, suggesting a target for interventions to minimize lung disease after tuberculous.

Major Neutrophil-Derived Soluble Mediators Associate With Baseline Lung Pathology and Post-Treatment Recovery in Tuberculosis Patients

Background

The inflammatory response to Mycobacterium tuberculosis results in variable degrees of lung pathology during active TB (ATB) with central involvement of neutrophils. Little is known about neutrophil-derived mediators and their role in disease severity at baseline and recovery upon TB treatment initiation.

Methods

107 adults with confirmed pulmonary TB were categorised based on lung pathology at baseline and following successful therapy using chest X-ray scores (Ralph scores) and GeneXpert bacterial load (Ct values). Plasma, sputum, and antigen-stimulated levels of MMP1, MMP3, MMP8, MMP9, MPO, S100A8/9, IL8, IL10, IL12/23(p40), GM-CSF, IFNγ, and TNF were analysed using multiplex cytokine arrays.

Results

At baseline, neutrophil counts correlated with plasma levels of MMP8 (rho = 0.45, p = 2.80E-06), S100A8 (rho = 0.52, p = 3.00E-08) and GM-CSF (rho = 0.43, p = 7.90E-06). Levels of MMP8 (p = 3.00E-03), MMP1 (p = 1.40E-02), S100A8 (p = 1.80E-02) and IL12/23(p40) (p = 1.00E-02) were associated with severe lung damage, while sputum MPO levels were directly linked to lung damage (p = 1.80E-03), Mtb load (p = 2.10E-02) and lung recovery (p = 2.40E-02). Six months of TB therapy significantly decreased levels of major neutrophil-derived pro-inflammatory mediators: MMP1 (p = 4.90E-12 and p = 2.20E-07), MMP8 (p = 3.40E-14 and p = 1.30E-05) and MMP9 (p = 1.60E-04 and p = 1.50E-03) in plasma and sputum, respectively. Interestingly, following H37Rv whole cell lysate stimulation, S100A8 (p = 2.80E-02), MMP9 (p = 3.60E-02) and MPO (p = 9.10E-03) levels at month 6 were significantly higher compared to baseline. Sputum MMP1 (p = 1.50E-03), MMP3 (p = 7.58E-04), MMP9 (p = 2.60E-02) and TNF (p = 3.80E-02) levels were lower at month 6 compared to baseline in patients with good lung recovery.

Conclusion

In this study, patients with severe lung pathology at baseline and persistent lung damage after treatment were associated with higher plasma and sputum levels of major pro-inflammatory neutrophil-derived mediators. Interestingly, low sputum MPO levels were associated with severe lung damage, higher Mtb burden and low recovery. Our data suggest that therapeutic agents which target these mediators should be considered for future studies on biomarkers and host-directed therapeutic approaches against TB-related lung pathology and/or lung recovery.

Association of Mortality and Years of Potential Life Lost With Active Tuberculosis in the United States

IMPORTANCE

Active tuberculosis (TB) disease leads to substantial mortality but is preventable through screening and treatment for latent TB infection. Early mortality after TB diagnosis (≤1 year) is well described, but delayed mortality (>1 year) among patients with active TB is poorly understood.

OBJECTIVE

To compare early and delayed mortality and years of potential life (YPL) lost among patients with active TB disease vs an age-, sex-, and year of diagnosis-matched comparison cohort without active TB disease.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study, conducted in the integrated health system of Kaiser Permanente Northern California, included patients with microbiologically confirmed active TB disease from January 1, 1997, to December 31, 2017, and a control cohort matched by age, sex, and year of diagnosis. Multivariable models were used to adjust for demographic and clinical characteristics. Patients with active TB disease prior to 1997 were excluded. Data were analyzed from January 1, 2019, to January 31, 2020.

EXPOSURE

Microbiologically confirmed TB disease.

MAIN OUTCOMES AND MEASURES

Early (≤1 year after TB diagnosis) and delayed (>1 year after TB diagnosis) all-cause mortality.

RESULTS

A total of 2522 patients who had active TB from 1997 to 2017 were identified, with 17 166 person-years of follow-up. The comparison cohort included 100 880 persons with 735 726 person-years of follow-up. In the active TB and comparison cohorts, similar percentages of persons were male (56.3% vs 55.6%), aged 45 to 64 years (33.7% vs 33.7%), and aged 65 years or older (24.7% vs 24.7%). Both early mortality (7.0%) and delayed mortality (16.3%) were higher among patients with active TB disease compared with those without active TB disease (1.1% and 12.0%, respectively). Patients with active TB disease had a significantly higher risk for early (adjusted hazard ratio [aHR], 7.29; 95% CI, 6.08-8.73) and delayed (aHR, 1.78; 95% CI, 1.61-1.98) mortality compared with the comparison cohort (P < .001). Active TB disease was associated with an adjusted -7.0 (95% CI, -8.4 to -5.5) YPL lost compared with the comparison cohort.

CONCLUSIONS AND RELEVANCE

In this study, patients with active TB disease had significantly higher early and delayed all-cause mortality when adjusting for demographic and clinical characteristics. These findings suggest that TB prevention through screening and treatment of latent TB infection could reduce mortality and YPL lost due to active TB disease.

Identification of risk factors for radiological sequelae in patients treated for pulmonary tuberculosis: Prospective observational cohort study

OBJECTIVE OF STUDY

This study is designed to assess risk factors & magnitude of residual radiological lesion in patients treated for pulmonary tuberculosis.

METHODS

This is a retrospective observational cohort study which included patients who were newly diagnosed as pulmonary tuberculosis and have completed 6 months of treatment.

STATISTICAL ANALYSIS

Categorical data were expressed as proportion and continuous data were expressed as mean ± SD. The obtained data were analysed by means of frequency distribution table and descriptive statistics using SPSS version 20 for Windows (SPSS Inc., Chicago, Ill, USA) and Chi-square test and student t test were used for statistical analysis. We assessed association between risk factors and development of radiological sequelae, using univariate statistical analysis and odds ratio. P-values less than 0.05 were considered statistically significant.

RESULTS

Data from 128 patients was used for analysis. The average age in this cohort was 32.84 ± 17.47 years and 68.75% patients were male. Residual x-ray lesions were observed in 92 (71.87%) cases out of 128 study patients. 72.82% of residual lesions appeared as parenchymal fibrosis, 13.04% as bronchiectasis, 2.17% as cavity & 3.26% appeared as calcification. Patients with advanced lesions (34.78% vs 16.66%), bilateral lesions (29.34% vs 11.11%) or cavity (18.47% vs 2.77%) in chest x-ray or Sputum smear positivity for AFB were found to have significant radiological sequelae. Among the variables associated with the risk of having pulmonary tuberculosis sequelae were cavity (OR: 7.03), sputum smear positive for AFB (OR: 4.03), Advanced lesions (OR: 3.38) & bilateral lesions (OR: 2.90) in chest x-ray.

CONCLUSION

This study concluded that a large number of patients remain with residual radiological sequelae despite good clinical response. Patients with extensive lesions, presence of cavity or bilateral involvement in chest x-ray and sputum smear positive for acid fast bacilli were often associated with residual radiological opacity.

Neutrophils in Tuberculosis-Associated Inflammation and Lung Pathology

Protective immunity to Mycobacterium tuberculosis (Mtb)—the causative agent of tuberculosis (TB)—is not fully understood but involves immune responses within the pulmonary airways which can lead to exacerbated inflammation and immune pathology. In humans, this inflammation results in lung damage; the extent of which depends on specific host pro-inflammatory processes. Neutrophils, though increasingly linked to the development of inflammatory disorders, have been less well studied in relation to TB-induced lung pathology. Neutrophils mode of action and their specialized functions can be directly linked to TB-specific lung tissue damage observed on patient chest X-rays at diagnosis and contribute to long-term pulmonary sequelae. This review discusses aspects of neutrophil activity associated with active TB, including the resulting inflammation and pulmonary impairment. It highlights the significance of neutrophil function on TB disease outcome and underlines the necessity of monitoring neutrophil function for better assessment of the immune response and severity of lung pathology associated with TB. Finally, we propose that some MMPs, ROS, MPO, S100A8/A9 and Glutathione are neutrophil-related inflammatory mediators with promising potential as targets for developing host-directed therapies for TB.

Prompt recognition of infectious pulmonary tuberculosis is critical to achieving elimination goals: a retrospective cohort study

INTRODUCTION

All pulmonary tuberculosis (PTB) cases are presumed to be infectious to some degree. This spectrum of infectiousness is independently described by both the acid-fast bacilli smear and radiographic findings. Smear-positive patients with chest radiographic findings that are typical for adult-type PTB are believed to be most infectious.

HYPOTHESIS

Characterisation of the presumed most infectious PTB case is possible by reference to readily available clinical features and laboratory results.

METHODS

Retrospective cohort study of adult, culture-positive PTB cases (151 smear-positive; 162 smear-negative) diagnosed between 1 January 2013 and 30 April 2017 in Canada. We describe cases according to demographic, clinical and laboratory features. We use multivariable multinomial logistic regression to estimate the relative risk ratio (RRR) with 95% CI of features associated with an outcome of smear-positive PTB, characterised by 'typical' chest radiograph findings.

RESULTS

Being Canadian-born, symptomatic, having a subacute duration of symptoms and broad-spectrum antibiotic prescriptions were all more commonly associated with smear-positive than smear-negative disease (36% vs 20%; 95% vs 63%; 88% vs 54%; and 59% vs 28%, respectively). After combining smear status and radiographic features, we show that smear-positive patients with typical chest radiographs were younger, had a longer duration of symptoms (RRR 2.41; 95% CI 1.01 to 5.74 and 2.93; 95% CI 1.20 to 7.11, respectively) and were less likely to be foreign-born, or have a moderate to high-risk factor for reactivation (RRR 0.40; 95% CI 0.17 to 0.92 and 0.18; 95% CI 0.04 to 0.71, respectively) compared with smear-negative patients with atypical chest radiograph findings.

CONCLUSION

A clear picture of the presumed most infectious PTB case emerges from available historical and laboratory information; vigilance for this presentation by front-line providers will support elimination strategies aimed at reducing transmission.

Transition from Restrictive to Obstructive Lung Function Impairment During Treatment and Follow-Up of Active Tuberculosis

Background

Pulmonary tuberculosis (PTB) is associated with many forms of chronic lung disease including the development of chronic airflow obstruction (AFO). However, the nature, evolution and mechanisms responsible for the AFO after PTB are poorly understood. The aim of this study was to examine the progression of changes in lung physiology in patients treated for PTB.

Methods

Immunocompetent, previously healthy, adult patients receiving ambulatory treatment for a first episode of tuberculosis were prospectively followed up with serial lung physiology and quantitative computed tomography (CT) lung scans performed at diagnosis of tuberculosis, 2, 6, 12 and 18 months during and after the completion of treatment.

Results

Forty-nine patients (median age 26 years; 37.2% males) were included, and 43 were studied. During treatment, lung volumes improved and CT fibrosis scores decreased, but features of AFO and gas trapping emerged, while reduced diffusing capacity (DLco) seen in a majority of patients persisted. Significant increases in total lung capacity (TLC) by plethysmography were seen in the year following treatment completion (median change 5.9% pred., P<0.01) and were driven by large increases in residual volume (RV) (median change +19%pred., P<0.01) but not inspiratory capacity (IC; P=0.41). The change in RV/TLC correlated with significant progression of radiological gas trapping after treatment (P=0.04) but not with emphysema scores. One year after completing treatment, 18.6% of patients had residual restriction (total lung capacity, TLC <80%pred), 16.3% had AFO, 32.6% had gas trapping (RV/TLC>45%), and 78.6% had reduced DLco.

Conclusion

Simple spirometry alone does not fully reveal the residual respiratory impairments resulting after a first episode of PTB. Changes in physiology evolve after treatment completion, and these findings when taken together, suggest emergence of gas trapping after treatment likely caused by progression of small airway pathology during the healing process.

Effects of host-directed therapies on the pathology of tuberculosis

Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), has co-evolved with the human immune system and utilizes multiple strategies to persist within infected cells, to hijack several immune mechanisms, and to cause severe pathology and tissue damage in the host. This delays the efficacy of current antibiotic therapy and contributes to the evolution of multi-drug-resistant strains. These challenges led to the development of the novel approach in TB treatment that involves therapeutic targeting of host immune response to control disease pathogenesis and pathogen growth, namely, host-directed therapies (HDTs). Such HDT approaches can (1) enhance the effect of antibiotics, (2) shorten treatment duration for any clinical form of TB, (3) promote development of immunological memory that could protect against relapse, and (4) ameliorate the immunopathology including matrix destruction and fibrosis associated with TB. In this review we discuss TB-HDT candidates shown to be of clinical relevance that thus could be developed to reduce pathology, tissue damage, and subsequent impairment of pulmonary function. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

A lung image reconstruction from computed radiography images as a tool to tuberculosis treatment control

Background

Background: Tuberculosis (TB) is an infectious lung disease with high worldwide incidence that severely compromises the quality of life in affected individuals. Clinical tests are currently employed to monitor pulmonary status and treatment progression. The present study aimed to apply a three-dimensional (3D) reconstruction method based on chest radiography to quantify lung-involvement volume of TB acute-phase patients before and after treatment. In addition, these results were compared with indices from conventional clinical exams to show the coincidence level.

Methods

A 3D lung reconstruction method using patient chest radiography was applied to quantify lung-involvement volume using retrospective examinations of 50 patients who were diagnosed with pulmonary TB and treated with two different drugs schemes. Twenty-five patients were treated with Scheme I (rifampicin, isoniazid, and pyrazinamide), whereas twenty-five patients were treated with Scheme II (rifampicin, isoniazid, pyrazinamide, and ethambutol). Acute-phase reaction: Serum exams included C-reactive protein levels, erythrocyte sedimentation rate, and albumin levels. Pulmonary function was tested posttreatment.

Results

We found strong agreement between lung involvement and serum indices pre- and posttreatment. Comparison of the functional severity degree with lung involvement based on 3D image quantification for both treatment schemes found a high correlation.

Conclusions

The present 3D reconstruction method produced a satisfactory agreement with the acute-phase reaction, most notably a higher significance level with the C-reactive protein. We also found a quite reasonable coincidence between the 3D reconstruction method and the degree of functional lung impairment posttreatment. The performance of the quantification method was satisfactory when comparing the two treatment schemes. Thus, the 3D reconstruction quantification method may be useful tools for monitoring TB treatment. The association with serum indices are not only inexpensive and sensitive but also may be incorporated into the assessment of patients during TB treatment.

Pulmonary function and respiratory health after successful treatment of drug-resistant tuberculosis

Background:

Post-treatment morbidity among subjects with drug-resistant tuberculosis (DR-TB) is unclear.

Methods:

This was a cross-sectional study of patients from Tbilisi, Georgia with cavitary DR-TB and an outcome of cure. Participants had a chest X-ray (CXR), St. George Respiratory Quality (SGRQ) survey, and pulmonary function tests (PFTs) performed. Correlations between SGRQ and PFT results and factors associated with pulmonary impairment were examined.

Results:

Among 58 subjects (median age 31 years), 40% used tobacco, 59% had prior TB, and 47% underwent adjunctive surgical resection. The median follow-up time was 41 months. Follow-up CXR revealed fibrosis in 30 subjects (52%) and bronchiectasis in seven (12%). The median forced expiratory volume (FEV₁)/forced vital capacity (FVC) ratio was 0.72, with 24 subjects (41%) having a ratio of ≤0.70. Significant correlations existed between PFT measures and overall and component SGRQ scores. In linear regression, age, prior TB, and CXR fibrosis or bronchiectasis were significantly associated with decreased pulmonary function. Adjunctive surgery was significantly associated with a higher percent predicted FEV₁ and FVC.

Conclusions:

A high proportion of DR-TB subjects had residual pulmonary impairment, particularly with recurrent TB and severe radiological disease. The association of surgical resection with improved lung function deserves further study. PFTs and SGRQ may both be useful to evaluate lung health.

The Immune Mechanisms of Lung Parenchymal Damage in Tuberculosis and the Role of Host-Directed Therapy

Impaired lung function is common in people with a history of tuberculosis. Host-directed therapy added to tuberculosis treatment may reduce lung damage and result in improved lung function. An understanding of the pathogenesis of pulmonary damage in TB is fundamental to successfully predicting which interventions could be beneficial. In this review, we describe the different features of TB immunopathology that lead to impaired lung function, namely cavities, bronchiectasis, and fibrosis. We discuss the immunological processes that cause lung damage, focusing on studies performed in humans, and using chest radiograph abnormalities as a marker for pulmonary damage. We highlight the roles of matrix metalloproteinases, neutrophils, eicosanoids and cytokines, like tumor necrosis factor-α and interleukin 1β, as well as the role of HIV co-infection. Finally, we focus on various existing drugs that affect one or more of the immunological mediators of lung damage and could therefore play a role as host-directed therapy.

[Pulmonary tuberculosis: Radiological evolution of broncho-pulmonary lesions at the end of treatment]

OBJECTIVES

To describe the residual broncho-pulmonary lesions and evaluate the role of CT scanning at the end of treatment of pulmonary tuberculosis.

MATERIALS AND METHODS

Analysis of the initial and end of treatment CT scans of 56 patients with pulmonary tuberculosis according to a reading grid including parenchymatous and airways lesions. The CT data at the end of treatment were analysed in relation to the clinical and microbiological data, and the original CT scan.

RESULTS

Active lesions (thick walled cavities and/or centrilobular micronodules) persisted in 24 patients (43%) after a mean treatment period of 7 months. The persistence of these signs of activity was correlated with the initial presence of a cavitary syndrome (p=0.027), with predominant sub-segmentary bronchial involvement, with extensive micronodular spread (p=0.024) and with bronchiectasis (p=0.04). These residual lesions were not associated with an increased risk of relapse.

CONCLUSION

The persistence of signs of activity on the CT scan at the end of treatment of tuberculosis do not necessarily correspond to an absence of cure but to a radiological delay. This imaging is nevertheless useful to make an assessment of any subsequent changes in the bronchial tree and to estimate the risk of later complications.

Predicting pulmonary tuberculosis in immigrants: a retrospective cohort study

Our objective was to investigate whether pulmonary tuberculosis (PTB) can be predicted from features of a targeted medical history and basic laboratory investigations in immigrants.

A retrospective cohort of 391 foreign-born adults referred to the Edmonton Tuberculosis Clinic (Edmonton, AB, Canada) was studied using multiple logistic regression analysis to predict PTB. Seven characteristics of disease were used as explanatory variables. Cross-validation assessed performance. Each predictor was tested on two outcomes: “culture-positive” and “smear-positive”. Receiver operating characteristic (ROC) curves were generated and the area under the ROC curve (AUC) was quantified.

Symptoms, subacute duration of symptoms, risk factors for reactivation of latent TB infection and anaemia were all associated with a positive culture (adjusted OR 1.79, 2.24, 1.72 and 2.28, respectively; p<0.05). Symptoms, inappropriate prescription of broad-spectrum antibiotics and a “typical” chest radiograph were associated with smear-positive PTB (adjusted OR 2.91, 1.55 and 12.34, respectively; p<0.05). ROC curve analysis was used to test each model, yielding AUC=0.91 for the outcome “culture-positive” disease and AUC=0.94 for the outcome “smear-positive” disease.

PTB among the foreign-born can be predicted from a targeted medical history and basic laboratory investigations, raising the threshold of suspicion in settings where the disease is relatively rare.

In high-income, low tuberculosis incidence countries, certain clinical characteristics should raise the threshold of suspicion to confirm a timely diagnosishttp://ow.ly/bRDZ30iPurz

Tuberculosis and lung damage: from epidemiology to pathophysiology

A past history of pulmonary tuberculosis (TB) is a risk factor for long-term respiratory impairment. Post-TB lung dysfunction often goes unrecognised, despite its relatively high prevalence and its association with reduced quality of life. Importantly, specific host and pathogen factors causing lung impairment remain unclear. Host immune responses probably play a dominant role in lung damage, as excessive inflammation and elevated expression of lung matrix-degrading proteases are common during TB. Variability in host genes that modulate these immune responses may determine the severity of lung impairment, but this hypothesis remains largely untested. In this review, we provide an overview of the epidemiological literature on post-TB lung impairment and link it to data on the pathogenesis of lung injury from the perspective of dysregulated immune responses and immunogenetics.

Host factors driving lung injury in TB likely contribute to variable patterns of pulmonary impairment after TBhttp://ow.ly/a3of30hBsxB

[Spirometric and radiographic profile of patients with pulmonary tuberculosis treated and cured at the Department of Pulmonology of Brazzaville University Hospital]

INTRODUCTION

Tuberculosis is a real public health problem in Congo. Pulmonary localization can lead to sequelae of respiratory functional repercussions.

OBJECTIVE

Describe the spirometric and radiographic profile of patients treated with pulmonary tuberculosis treated and cured.

PATIENTS AND METHODS

This was a cross-sectional study that included 150 patients with previous pulmonary tuberculosis with positive microscopy treated and cured in the Pulmonary Department of Brazzaville University Hospital. In which we performed a functional exploration (Spirometry) and a chest X-ray. The study took place from 1st January 2016 to 31st August 2016.

RESULTS

The spirometry performed in all patients was pathological in 68.67% (103 cases/150) of the cases. Among them 74.76% (77 cases/103) had a restrictive profile (FEV1/FVC >70% and CVF <80%), 9.71% (10 cases/103) an obstructive syndrome (FEV1/FVC ≤70% and CVF >80%) and 15.53% (16 cases/103) a mixed syndrome (FVC <80% and FEV1/FVC <70%). Of the 150 chest radiographs performed, 120 or 80% were pathological; the degree of parenchymal stage III destruction represented 28.33%. There was a significant correlation between the degree of parenchymal destruction and the delay in treatment on the one hand and between the degree of parenchymal destruction and the different pulmonary volumes and volumes on the other hand.

CONCLUSION

The prevention of these respiratory functional disorders is based on the prophylaxis of tuberculosis on early diagnosis of the disease.

Comorbidities in pulmonary tuberculosis cases in Puducherry and Tamil Nadu, India: Opportunities for intervention

Background

We aimed to define characteristics of TB patients in Puducherry and two districts of Tamil Nadu, India and calculate the population attributable fractions (PAF) of TB from malnutrition and alcohol.

Methods

New smear-positive TB cases were enrolled into the Regional Prospective Observational Research for Tuberculosis (RePORT India) cohort. Census and National Family Health Survey data were used for comparisons.

Results

Data were analyzed for 409 participants enrolled between May 2014-June 2016; 307 (75.1%) were male, 60.2% were malnourished (body mass index [BMI] <18.5 kg/m²), and 29.1% severely malnourished (BMI <16). “Hazardous” alcohol use (based on AUDIT-C score) was reported by 155/305 (50.8%) of males. Tuberculosis cases were more likely than the Puducherry population to be malnourished (62.6% v 10.2% males and 71.7% v 11.3% of females; both p<0.001), and male cases were more likely to use alcohol than male non-cases (84.4% v 41%; p < .001). The PAF of malnutrition was 57.4% in males and 61.5% in females; the PAF for alcohol use was 73.8% in males and 1.7% in females.

Conclusions

Alcohol use in men and malnutrition are helping drive the TB epidemic in Southern India. Reducing the TB burden in this population will require efforts to mitigate these risk factors.

Impaired pulmonary function after treatment for tuberculosis: the end of the disease?

Objective:

To evaluate the prevalence of pulmonary function abnormalities and to investigate the factors affecting lung function in patients treated for pulmonary tuberculosis.

Methods:

A total of 214 consecutive patients (132 men and 82 women; 20-82 years of age), treated for pulmonary tuberculosis and followed at a local dispensary, underwent spirometry and plethysmography at least one year after treatment.

Results:

Pulmonary impairment was present in 102 (47.7%) of the 214 patients evaluated. The most common functional alteration was obstructive lung disease (seen in 34.6%). Of the 214 patients, 60 (28.0%) showed reduced pulmonary function (FEV₁ below the lower limit of normal). Risk factors for reduced pulmonary function were having had culture-positive pulmonary tuberculosis in the past, being over 50 years of age, having recurrent tuberculosis, and having a lower level of education.

Conclusions:

Nearly half of all tuberculosis patients evolve to impaired pulmonary function. That underscores the need for pulmonary function testing after the end of treatment.

Tuberculosis associated chronic obstructive pulmonary disease

OBJECTIVES

Reviewed the epidemiology, clinical characteristics, mechanisms, and treatment of tuberculosis associated chronic obstructive pulmonary disease.

DATA SOURCE

We searched PubMed, EMBASE, and the CINAHL from inception to June 2016. We used the following search terms: Tuberculosis, COPD, Tuberculosis associated COPD, and so forth. All types of study were chosen.

RESULTS AND CONCLUSION

Chronic obstructive pulmonary disease (COPD) and tuberculosis are significant public health problems, particularly in developing countries. Although, smoking is the conventional risk factor for COPD, nonsmoking related risk factors such as biomass fuel exposure, childhood lower-respiratory tract infections, chronic asthma, outdoor air pollution, and prior history of pulmonary tuberculosis have become important risk factors of COPD, particularly in developing countries. Past history of tuberculosis as a risk factor of chronic airflow obstruction has been reported in several studies. It may develop during the course of tuberculosis or after completion of tuberculosis treatment. Developing countries with large burden of tuberculosis can contribute significantly to the burden of chronic airflow obstruction. Prompt diagnosis and treatment of tuberculosis should be emphasized to lessen the future burden of chronic airflow obstruction.

A Systematic Review of the Prevalence and Pattern of Imaging Defined Post-TB Lung Disease

Background

Tuberculosis is an important risk factor for chronic respiratory disease in resource poor settings. The persistence of abnormal spirometry and symptoms after treatment are well described, but the structural abnormalities underlying these changes remain poorly defined, limiting our ability to phenotype post-TB lung disease in to meaningful categories for clinical management, prognostication, and ongoing research. The relationship between post-TB lung damage and patient-centred outcomes including functional impairment, respiratory symptoms, and health related quality of life also remains unclear.

Methods

We performed a systematic literature review to determine the prevalence and pattern of imaging-defined lung pathology in adults after medical treatment for pleural, miliary, or pulmonary TB disease. Data were collected on study characteristics, and the modality, timing, and findings of thoracic imaging. The proportion of studies relating imaging findings to spirometry results and patient morbidity was recorded. Study quality was assessed using a modified Newcastle-Ottowa score. (Prospero Registration number CRD42015027958)

Results

We identified 37 eligible studies. The principle features seen on CXR were cavitation (8.3–83.7%), bronchiectasis (4.3–11.2%), and fibrosis (25.0–70.4%), but prevalence was highly variable. CT imaging identified a wider range of residual abnormalities than CXR, including nodules (25.0–55.8%), consolidation (3.7–19.2%), and emphysema (15.0–45.0%). The prevalence of cavitation was generally lower (7.4–34.6%) and bronchiectasis higher (35.0–86.0%) on CT vs. CXR imaging. A paucity of prospective data, and data from HIV-infected adults and sub-Saharan Africa (sSA) was noted. Few studies related structural damage to physiological impairment, respiratory symptoms, or patient morbidity.

Conclusions

Post-TB structural lung pathology is common. Prospective data are required to determine the evolution of this lung damage and its associated morbidity over time. Further data are required from HIV-infected groups and those living in sSA.

Pulmonary impairment after tuberculosis in a South African population

Background

In South Africa, pulmonary tuberculosis (PTB) remains a problem of epidemic proportions. Despite evidence demonstrating persistent lung impairment after PTB cure, few population-based South African studies have investigated this finding. Pulmonary rehabilitation post-cure is not routinely received.

Objectives

To determine the effects of PTB on lung function in adults with current or past PTB. To determine any association between PTB and chronic obstructive pulmonary disease (COPD).

Methods

This study was observational and cross-sectional in design. Participants (n = 55) were included if they were HIV positive on treatment, had current PTB and were on treatment, and/or had previous PTB and completed treatment or if they were healthy adult subjects with no history of PTB. A sample of convenience was used with participants coming from a similar socio-economic background and undergoing spirometry testing. Multiple regression analyses were conducted on each lung function variable.

Results

Compared to normal percentage-predicted values, forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC) and FEV₁:FVC were significantly reduced in those with current PTB by 23.39%, 15.99% and 6.4%, respectively. Both FEV₁ and FVC were significantly reduced in those with past PTB by 11.76% and 10.79%, respectively. There was no association between PTB and COPD – those with previous PTB having a reduced FEV₁:FVC (4.88% less than the norm), which was just short of significance (p = 0.059).

Conclusions

Lung function is reduced both during and after treatment for PTB and these deficits may persist. This has implications regarding the need for pulmonary rehabilitation even after medical cure.

Risk factors associated with development of pulmonary impairment after tuberculosis

BACKGROUND

Treatment of pulmonary tuberculosis (PTB) focuses on microbiological cure and radiological improvement. However, many patients develop pulmonary impairment after the completion of anti-tubercular therapy (ATT), which affects their quality of life (QoL).

AIM AND OBJECTIVE

To study the occurrence and severity of pulmonary impairment after tuberculosis (PIAT), risk factors associated with development of PIAT and QoL after development of PIAT.

METHODOLOGY

146 eligible PTB patients, who completed their ATT during January 2013 to December 2013 at National Institute of TB and Respiratory Diseases (NITRD), New Delhi and peripheral centres were enrolled after informed consent and evaluated. PIAT was graded using spirometric parameters. Severity of dyspnoea was assessed using Borg scale and Medical Research Council (MRC) scale. QoL was assessed using Seattle's Obstructive Lung Diseases Questionnaire (SOLDQ).

RESULTS

74% (108) had PIAT. On univariate analysis, smoking, education, body mass index (BMI), duration of illness prior to diagnosis of TB and number of prior ATT courses taken were the significant risk factors associated with the development of PIAT. On multiple logistic regression, patients who had taken ATT more than once was the independent risk factor associated with PIAT. Severity of dyspnoea was increased on both Borg scale and MRC scale with the increase in impairment of lung function. QoL was lower in patients with severe impairment.

CONCLUSION

After bacteriological cure of TB after treatment, significant numbers of patients have poor lung function and poor QoL. There is need for prevention and management of such sequelae under national programme.

Correlation of chest computed tomography findings with dyspnea and lung functions in post-tubercular sequelae

Aims:

To study the correlation between dyspnea, radiological findings, and pulmonary function tests (PFTs) in patients with sequelae of pulmonary tuberculosis (TB).

Materials and Methods:

Clinical history, chest computed tomography (CT), and PFT of patients with post-TB sequelae were recorded. Dyspnea was graded according to the Modified Medical Research Council (mMRC) scale. CT scans were analyzed for fibrosis, cavitation, bronchiectasis, consolidation, nodules, and aspergilloma. Semi-quantitative analysis was done for these abnormalities. Scores were added to obtain a total morphological score (TMS). The lungs were also divided into three zones and scores added to obtain the total lung score (TLS). Spirometry was done for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), and FEV₁/FVC.

Results:

Dyspnea was present in 58/101 patients. A total of 22/58 patients had mMRC Grade 1, and 17/58 patients had Grades 2 and 3 dyspnea each. There was a significant difference in median fibrosis, bronchiectasis, nodules (P < 0.01) scores, TMS, and TLS (P < 0.0001) between dyspnea and nondyspnea groups. Significant correlations were obtained between grades of dyspnea and fibrosis (r = 0.34, P = 0.006), bronchiectasis (r = 0.35, P = 0.004), nodule (r = 0.24, P = 0.016) scores, TMS (r = 0.398, P = 0.000), and TLS (r = 0.35, P = 0.0003). PFTs were impaired in 78/101 (77.2%) patients. Restrictive defect was most common in 39.6% followed by mixed in 34.7%. There was a negative but statistically insignificant trend between PFT and fibrosis, bronchiectasis, nodule scores, TMS, and TLS. However, there were significant differences in median fibrosis, cavitation, and bronchiectasis scores in patients with normal, mild to moderate, and severe respiratory defects. No difference was seen in TMS and TLS according to the severity of the respiratory defect.

Conclusion:

Both fibrosis and bronchiectasis correlated with dyspnea and with PFT. However, this correlation was not linear. The overall extent of radiological abnormalities correlated only with dyspnea but not with PFT.

Making a timely diagnosis of pulmonary tuberculosis

Making a timely diagnosis of adult-type pulmonary tuberculosis (TB) is critical to interrupting transmission and optimizing treatment outcomes. A hypothesis based on clinical experience is that a timely diagnosis may be made by addressing seven clinical rubrics: six related to history, one to the laboratory. Responses may be considered to be part of a clinical heuristic for making a timely diagnosis of pulmonary TB. The larger the number of affirmative responses, the more likely the diagnosis, although it is probable some questions carry more weight than others. The radiograph is key and may almost be considered to be confirmatory of the history. Collectively, the responses should prompt suspicion of pulmonary TB - submission of sputum for acid-fast bacilli smear and culture, and respiratory isolation.

Factors associated with abnormal spirometry among HIV-infected individuals

OBJECTIVE

HIV-infected individuals are susceptible to development of chronic lung diseases, but little is known regarding the prevalence and risk factors associated with different spirometric abnormalities in this population. We sought to determine the prevalence, risk factors and performance characteristics of risk factors for spirometric abnormalities among HIV-infected individuals.

DESIGN

Cross-sectional cohort study.

METHODS

We analyzed cross-sectional US data from the NHLBI-funded Lung-HIV consortium - a multicenter observational study of heterogeneous groups of HIV-infected participants in diverse geographic sites. Logistic regression analysis was performed to determine factors statistically significantly associated with spirometry patterns.

RESULTS

A total of 908 HIV-infected individuals were included. The median age of the cohort was 50 years, 78% were men and 68% current smokers. An abnormal spirometry pattern was present in 37% of the cohort: 27% had obstructed and 10% had restricted spirometry patterns. Overall, age, smoking status and intensity, history of Pneumocystis infection, asthma diagnosis and presence of respiratory symptoms were independently associated with an abnormal spirometry pattern. Regardless of the presence of respiratory symptoms, five HIV-infected participants would need to be screened with spirometry to diagnose two individuals with any abnormal spirometry pattern.

CONCLUSIONS

Nearly 40% of a diverse US cohort of HIV-infected individuals had an abnormal spirometry pattern. Specific characteristics including age, smoking status, respiratory infection history and respiratory symptoms can identify those at risk for abnormal spirometry. The high prevalence of abnormal spirometry and the poor predictive capability of respiratory symptoms to identify abnormal spirometry should prompt clinicians to consider screening spirometry in HIV-infected populations.