The global prevalence of latent tuberculosis: a systematic review and meta-analysis

An mRNA vaccine induces antimycobacterial immunity by activating DNA damage repair and autophagy

Effective vaccines are urgently needed for the control of tuberculosis (TB). Here, we report that an mRNA TB vaccine is highly effective and exhibits both prophylactic and therapeutic activity in the zebrafish model of TB. Adult zebrafish immunized with the mRNA vaccine survived significantly longer after Mycobacterium marinum challenge compared to those immunized with the DNA vaccine. Furthermore, post-infection treatment with the mRNA vaccine drastically reduced the bacterial burden. The mRNA vaccine activated multiple DNA break repair systems that are essential for the normal development and function of adaptive immunity, but did not activate the canonical DNA damage responses that promote cell death. This highlights a profound connection between DNA damage repair and the activation of immune responses under physiological processes of immunization. Remarkably, the mRNA vaccine induced autophagy in granulomas, coinciding with bacterial killing and cell survival. Collectively, these findings demonstrate that the mRNA vaccine elicits potent innate and adaptive immunity, providing effective host protection against mycobacterial challenge.

Assessing the risk of TB progression: Advances in blood-based biomarker research

This review addresses the significant advancements in the identification of blood-based prognostic biomarkers for tuberculosis (TB), highlighting the importance of early detection to prevent disease progression. The manuscript discusses various biomarker categories, including transcriptomic, proteomic, metabolomic, immune cell-based, cytokine-based, and antibody response-based markers, emphasizing their potential in predicting TB incidence. Despite promising results, practical application is hindered by high costs, technical complexities, and the need for extensive validation across diverse populations. Transcriptomic biomarkers, such as the Risk16 signature, show high sensitivity and specificity, while proteomic and metabolic markers provide insights into protein-level changes and biochemical alterations linked to TB. Immune cell and cytokine markers offer real-time data on the body's response to infection. The manuscript also explores the role of single-nucleotide polymorphisms in TB susceptibility and the challenges of implementing novel RNA signatures as point-of-care tests in low-resource settings. The review concludes that, while significant progress has been made, further research and development are necessary to refine these biomarkers, improve their practical application, and achieve the World Health Organization's TB elimination goals.

Comparative diagnostic accuracy of ChatGPT-4 and machine learning in differentiating spinal tuberculosis and spinal tumors

BACKGROUND

In clinical practice, distinguishing between spinal tuberculosis (STB) and spinal tumors (ST) poses a significant diagnostic challenge. The application of AI-driven large language models (LLMs) shows great potential for improving the accuracy of this differential diagnosis.

PURPOSE

To evaluate the performance of various machine learning models and ChatGPT-4 in distinguishing between STB and ST.

STUDY DESIGN

A retrospective cohort study.

PATIENT SAMPLE

143 STB cases and 153 ST cases admitted to Xiangya Hospital Central South University, from January 2016 to June 2023 were collected.

OUTCOME MEASURES

This study incorporates basic patient information, standard laboratory results, serum tumor markers, and comprehensive imaging records, including Magnetic Resonance Imaging (MRI) and Computed Tomography (CT), for individuals diagnosed with STB and ST. Machine learning techniques and ChatGPT-4 were utilized to distinguish between STB and ST separately.

METHOD

Six distinct machine learning models, along with ChatGPT-4, were employed to evaluate their differential diagnostic effectiveness.

RESULT

Among the 6 machine learning models, the Gradient Boosting Machine (GBM) algorithm model demonstrated the highest differential diagnostic efficiency. In the training cohort, the GBM model achieved a sensitivity of 98.84% and a specificity of 100.00% in distinguishing STB from ST. In the testing cohort, its sensitivity was 98.25%, and specificity was 91.80%. ChatGPT-4 exhibited a sensitivity of 70.37% and a specificity of 90.65% for differential diagnosis. In single-question cases, ChatGPT-4's sensitivity and specificity were 71.67% and 92.55%, respectively, while in re-questioning cases, they were 44.44% and 76.92%.

CONCLUSION

The GBM model demonstrates significant value in the differential diagnosis of STB and ST, whereas the diagnostic performance of ChatGPT-4 remains suboptimal.

Evaluating stratified T-SPOT.TB results for diagnostic accuracy in tuberculosis disease: a retrospective cohort study with sensitivities, specificities, and predictive values

OBJECTIVES

To investigate the association between quantitative T-SPOT.TB values and the risk of incident and prevalent tuberculosis disease (TBD), identify risk factors, and evaluate test accuracy.

METHODS

This retrospective cohort study followed patients tested consecutively with T-SPOT.TB at Aarhus University Hospital from 2010 to 2017 through 2022. Data on demographics, comorbidities, medications, and TB status were collected from patient records and national registries. Cox proportional hazards models with restricted cubic splines assessed the risk of incident TBD (occurring ≥3 months post-test) by quantitative spot counts. Cox and log-binomial regressions identified risk factors for incident and prevalent TBD (occurring between three months before and after the test). Sensitivity, specificity, and predictive values assessed test accuracy. T-SPOT.TB was the index test, and microbiologically and/or clinically confirmed TBD was the reference standard.

RESULTS

Among 8,542 individuals with complete follow-up, 59 developed incident TBD over 67,456 person-years. Among 9,014 individuals tested once, 162 had prevalent TBD at the time of testing. The risk of incident TBD increased with higher spot counts, plateauing for tests with more than ten spots. The strongest risk factors for both incident and prevalent TBD were categorical T-SPOT.TB results: compared to negative tests (≤4 spots), adjusted hazard ratios for incident TBD were 5.0 (95%CI: 1.9, 13.1) for borderline (5-7 spots) and 8.0 (95%CI: 4.0, 15.7) for positive tests (≥8 spots). Adjusted risk ratios for prevalent TBD were 14.9 (95%CI: 7.7, 28.9) for borderline and 35.6 (95%CI: 21.4, 59.2) for positive tests. Sensitivities for incident and prevalent TBD were 54.0% (95% CI: 39.3, 68.2) and 78.4% (95% CI: 71.3, 84.5), respectively. Specificities were 84.8 (84.0, 85.4) and 83.7 (82.9, 84.4), respectively.

CONCLUSIONS

Incident TBD risk increases with T-SPOT.TB values but plateaus beyond 10 spots. Borderline and positive T-SPOT.TB results are strongly linked to TBD risk.

Enhancing Antituberculosis Treatment Nanoparticles Encapsulated with Catalase and Levofloxacin Under Ultrasound Stimulation: A 3D Spheroid Study

Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (MTB). Tuberculous granuloma is the central and key pathological structure of tuberculosis and is characterized by tissue hypoxia and ineffective drug delivery. To address these issues, this study fabricated a composite nanoparticle loaded with catalase (CAT) and levofloxacin (LEV) (CAT@LEV-NPs) and then combined it with ultrasound (US) to investigate the bactericidal effect and underlying mechanisms using TB spheroids. The TB spheroids were constructed using attenuated Bacillus Calmette-Guérin (BCG) instead of MTB to facilitate operation under general experimental conditions. This study examined the physical properties and oxygen production efficiency of CAT@LEV-NPs. Subsequently, we treated TB spheroids with nanoparticles alone or in combination with US and found that ultrasound significantly increased drug permeability and activated CAT@LEV-NPs to produce a large number of reactive oxygen species (ROS). The combined treatment showed excellent antibacterial effects, resulting in more severe damage to the bacterial structure than other treatments. Additionally, the combined treatment induced a higher M1 polarization of macrophages, increased the apoptosis rate, and improved the anoxic microenvironment in TB spheroids. These factors may be closely related to the enhanced bactericidal effects of combined treatment. In conclusion, our study suggests that US combined with CAT@LEV-NPs could serve as a novel, noninvasive, safe, and effective treatment modality for intractable MTB infections.

Latent tuberculosis prevalence in healthcare workers in Laos: a cross-sectional study

BACKGROUND

Individuals with latent tuberculosis infection (LTBI) have a high risk of active infection, morbidity and mortality. Healthcare workers are a group who have increased risk of infection and onward transmission to their patients and other susceptible individuals; however, LTBI is often undiagnosed, and individuals are asymptomatic. Interferon gamma release assays (IGRA) can detect evidence of TB infection in otherwise asymptomatic individuals and are a good indication of LTBI. Laos, a resource limited country in southeast Asia, has limited data on TB prevalence in the general population or in healthcare workers. This study aimed to estimate the prevalence of LTBI in Lao healthcare workers in Vientiane Capital.

METHODS

Healthcare workers from high-risk departments from 3 central hospitals in Laos were included (n = 196) and venous blood was tested by IGRA. A questionnaire was administered to determine their knowledge, attitude and practice towards TB and LTBI.

RESULTS

10.2% of the participants were positive by IGRA, none of whom were previously aware of their TB status. The questionnaire revealed that knowledge and awareness of TB and LTBI were low.

DISCUSSION

A significant proportion of healthcare workers in this study had evidence of LTBI infection. These individuals were unaware of their TB status and we suggest that testing and treatment, as well as prevention strategies, should be routinely administered in Lao hospitals.

Clinical Features and Predictors of Treatment Outcome in Patients with Ocular Tuberculosis from the Netherlands and Indonesia: The OculaR TB in Low versus High Endemic Countries (ORTEC) Study

PURPOSE

To describe and compare clinical features, treatment approaches, and treatment outcomes of ocular tuberculosis (OTB) patients in the Netherlands, a low tuberculosis (TB)-endemic country, and Indonesia, a high TB-endemic country. We also aimed to identify predictors of treatment outcomes.

METHODS

A medical chart review of 339 OTB patients (n = 93 from the Netherlands and n = 246 from Indonesia) was performed. The primary outcome was response to treatment, whether with or without anti-tubercular treatment, after six months of treatment initiation (good versus poor responders).

RESULTS

Indonesian OTB patients displayed a higher prevalence of chest radiograph findings indicative of TB infection (p < 0.001) and concurrent active systemic TB (p = 0.011). Indonesian cohort exhibited a more acute and severe disease profile, including uveitis duration ≤ 3 months (p < 0.001), blindness (p < 0.001), anterior chamber (AC) cells ≥ 2+ (p < 0.001), and posterior synechiae (p < 0.001). Overall proportions of good responders to treatment were 67.6% in the Netherlands and 71.5% in Indonesia. Presence of AC cell ≥ 2+ (adjusted odds ratio (aOR): 2.12, 95% CI: 1.09-4.14), choroidal lesions other than serpiginous-like choroiditis (SLC) or tuberculoma (aOR: 4.47, 95% CI: 1.18-16.90), and retinal vasculitis (aOR: 2.32, 95% CI: 1.10-4.90) at baseline were predictors for poor response to treatment.

CONCLUSIONS

Despite a more severe initial clinical presentation in the Indonesian cohort, the overall treatment outcomes of OTB was comparable in both cohorts. Three baseline clinical features were identified as predictors of treatment outcomes.

Association of acid-suppressive therapy and tuberculosis: A causal or coincidental link to the infection?

BACKGROUND

Acid-suppressant proton-pump inhibitors (PPI) and histamine-2-receptor antagonists (H2RA) are associated with an increased risk of tuberculosis (TB). However, it remains unclear whether this association is causal or coincidental.

METHODS

Patients newly diagnosed with TB between 2000 and 2013 were identified from the Taiwan National Health Insurance Database. Each patient with TB was matched in a 1:10 ratio with patients without TB by age, sex, and index date. The time lags from the end of PPI or H2RA treatment to the index date, and respective cumulative doses in the 90 days before the index date, were analyzed for association with TB.

RESULTS

The age (mean [standard deviation] 60.8 [17.3] years) and sex ratio (69.4% males) were comparable between patients with TB (n = 6002) and patients without TB (n = 60,020). Previous PPI or H2RA treatment was more frequently observed in patients with TB (16.6% vs. 8.9%, p < 0.001). Concurrent antacid therapy posed the highest risk for TB (odds ratio [OR] 4.21 for PPI and 2.24 for H2RA, both p < 0.0001), and the closer to the end of the therapy, the more likely TB was detected (p for trend: 0.0077 for PPI and 0.0145 for H2RA). The cumulative doses of antacid in the 90 days before TB had an inverse relationship with TB risk. PPI, used either alone or in combination with H2RA, conferred a higher risk of TB than H2RA alone.

CONCLUSIONS

Tuberculosis should be considered in symptomatic patients receiving or recently ceased antacid therapy with PPI or H2RA in TB endemic areas.

Evaluation of nonpolar lipid extract antigen-based enzyme-linked immunosorbent assay for the serodiagnosis of tuberculosis

This study assessed the diagnostic potential of nonpolar lipid extracts in enzyme-linked immunosorbent assays (ELISAs) for tuberculosis (TB) serodiagnosis. Nonpolar lipid extracts were harvested from Mycobacterium tuberculosis (Mtb) knockout in mce1 operon (∆mce1) and its parental wild type (WT) strains. IgM and IgG anti-nonpolar lipid serum levels were measured in TB patients (n=45), healthy individuals with positive (n=22) and negative (n=44) interferon-gamma release assay (IGRA) results, and symptomatic respiratory (SR) patients with negative TB tests (n=9). IgG anti-WT lipid distinguished TB patients from IGRA-positive individuals with 60% sensitivity and 77.3% specificity. Conversely, IgG anti-∆mce lipid levels didn't vary significantly across groups. Interestingly, most SR patients exhibited significantly higher IgM and IgG anti-WT lipid titers than the IGRA-positive and -nega groups. While the overall diagnostic potential of Mtb nonpolar lipids was limited, the impaired immunogenecity of Δmce1 lipid extract suggests that some missing lipid classes in this extract can potentially induce antibody production in TB patients.

Tuberculosis Preventive Treatment in High TB-Burden Settings: A State-of-the-Art Review

Tuberculosis (TB) is the leading cause of death from a single infectious agent. The burden is highest in some low- and middle-income countries. One-quarter of the world's population is estimated to have been infected with TB, which is the seedbed for progressing from TB infection to the deadly and contagious disease itself. Although some individuals may clear their infections through innate and acquired immunity, many do not. People living with HIV, TB-exposed household contacts, other individuals recently infected, and immunosuppressed individuals are at especially high risk of progressing to TB disease. There have been major advances in recent years to support the programmatic management of TB infection. New tests of infection, including those that predict progression to TB disease, have become available. Numerous World Health Organization-recommended TB preventive treatment (TPT) regimens are available for all ages and for both drug-susceptible and drug-resistant TB infection. All regimens are generally safe, efficacious, and cost effective and have a low risk of generating resistance. TPT is recommended for pregnant women who are at risk for developing TB, but some regimens are associated with an increased likelihood of poor obstetric and fetal outcomes, and newer regimens have not yet been tested in pregnancy. New formulations of rifapentine-based TPT have been developed, and the cost has been radically reduced. Innovative models of delivery to support the scale up of TPT have been developed. Modeling suggests that scaling up TPT, especially regimens with optimal target product profile characteristics, can contribute substantially to ending the TB epidemic. The global uptake of TPT has increased substantially, especially for people living with HIV. Implementation gaps remain, particularly for children, pregnant women, and other household contacts. Further innovation is required to support the continued scale up of TPT and to contribute to ending the TB epidemic.

The Utility of Interferon-γ Release Assays in the Diagnosis of Tuberculosis in Patients With Cancer

BACKGROUND

Patients with cancer are at elevated risk for tuberculosis (TB) reactivation. Diagnosis of latent TB infection and TB disease remains challenging in this patient population despite the advent of interferon-γ release assays (IGRA).

METHODS

We retrospectively reviewed medical records of all patients with cancer who had IGRA testing (QuantiFERON-TB [QFT-TB] or T-SPOT.TB) at a major cancer center in the United States from June 2010 to July 2017. The results were analyzed with respect to the likelihood of latent TB infection and TB disease.

RESULTS

A total of 1299 patients were included with 1599 tests performed: 586 QFT-TB and 1013 T-SPOT.TB. Forty-nine (4%) patients were diagnosed with latent TB, and four (1%) with TB disease. T-SPOT.TB was more likely to yield an actionable result (positive or negative) than QFT-TB (89% vs. 65%, p < 0.001). The rate of indeterminate results for QFT-TB was higher than the rate of invalid results for T-SPOT.TB (35% and 10%, respectively, p < 0.001). On multivariate analysis, independent predictors of an invalid T-SPOT.TB included prior receipt of alemtuzumab, lower hemoglobin, absolute lymphocyte count, or serum albumin (p < 0.05 each), whereas the independent predictors of an indeterminate QFT-TB were female gender, prior receipt of systemic corticosteroids, and lower hemoglobin, or serum albumin or higher absolute neutrophil count (p < 0.05 each).

CONCLUSIONS

T-SPOT.TB yielded more actionable results than QFT-TB in patients with cancer. T-SPOT.TB might be a better IGRA for screening for latent TB infection in patients with cancer, although a direct comparison would be needed to definitively determine this.

Diagnosis and treatment of latent tuberculosis infection among household contacts in inland Bahia, Brazil: a cross-sectional follow-up study

BACKGROUND

The diagnosis and treatment of latent tuberculosis infection (LTBI) are crucial for tuberculosis (TB) control. Household contacts (HHC) of patients with pulmonary TB are at a high risk of LTBI due to their close proximity to source cases.

OBJECTIVE

To describe the diagnosis and treatment of LTBI among HHC.

DESIGN AND SETTING

This cross-sectional follow-up study was conducted in the municipality of Paulo Afonso, northeastern Brazil, between 2013 and 2022.

METHODS

We retrieved secondary data from the medical records of HHC who were followed up at a specialized referral center for TB. LTBI prevalence estimates were calculated and are presented with 95% confidence intervals (CIs).

RESULTS

In total, 622 HHC were screened for LTBI, with 620 evaluated using the tuberculin skin test (TST). Of these, 40 (6.5%) did not return for TST reading. The overall prevalence of LTBI was 53.1% (95% CI: 49-57.1%), with a high prevalence among females and individuals aged 25-34 years. The overall LTBI treatment initiation rate was 26.1% (95%CI: 21.5-31.3%), and 64.2% (95%CI: 53.3-73.8%) of HHC who initiated treatment completed their course.

CONCLUSION

This study revealed a high prevalence of LTBI among HHC, particularly among women and individuals aged 25-34 years, underscoring the ongoing TB transmission within the community. Only 26.1% of the diagnosed HHC initiated treatment, with approximately 64% completing their course. This highlights the challenges in managing LTBI and emphasizes the need for targeted screening and interventions for high-risk groups.

Epidemiology of Latent Tuberculosis in Rheumatic Immune-Mediated Inflammatory Diseases-Study of 1117 Patients and Descriptive Literature Review

Background/Objectives: Patients with rheumatic immune-mediated diseases (rheumatic-IMID) and latent tuberculosis (LTBI) are at an increased risk of developing active tuberculosis (TB); therefore, screening is recommended before starting biological treatment. The aims of this study were as follows: (i) to assess the prevalence of LTBI, (ii) to determine the importance of using a booster test in TST-negative patients, (iii) to compare the tuberculin skin test (TST) with the interferon-gamma release assay (IGRA), (iv) to perform a review of the prevalence of LTBI. Methods: A cross-sectional hospital study was performed, including patients diagnosed with rheumatic-IMID who underwent a TST and/or IGRA during the period 2016-2020. If the first TST was negative, a new TST (booster) was performed. Results: A total of 1117 patients were included. The overall prevalence of LTBI was estimated to be 31.7% (95% confidence interval, 29.74-33.66). The LTBI prevalence ranged from 38.5% for vasculitis to 14% for sarcoidosis. The booster test was positive in 22.9% of 817 patients with a negative or indeterminate IGRA. The IGRA was positive in 3.8% of 793 patients with a negative booster.The adjusted Cohen's kappa coefficient between TST (+booster) and IGRA was 0.62. Conclusions: LTBI is frequent in patients with rheumatic-IMID. IGRA and TST (+booster) show a moderate, fair grade of agreement. Therefore, performing both tests before biological therapy should be highly recommended.

Investigation of the prevalence of latent tuberculosis in cancer patients compared to non-cancer patients: a case-control study

Background

Latent tuberculosis (TB) can reactivate in immunocompromised individuals, such as cancer patients undergoing chemotherapy, leading to severe complications. Understanding the prevalence of latent TB in this high-risk group is crucial, especially in regions with moderate to high TB burdens.

Aim

This study aims to determine the prevalence of latent tuberculosis in cancer patients before chemotherapy and immunotherapy to guide preventive interventions and reduce the risk of TB reactivation.

Methods

This case-control study was conducted at Sina Hospital in Tehran, Iran, from 2012 to 2022. A total of 392, including 107 newly diagnosed cancer (case) and 285 non-cancer (control) patients, were enrolled in this study. All patients had received the Bacillus Calmette-Guérin (BCG) vaccine at the age of one. They underwent a thorough clinical examination and were screened using the tuberculin skin test (TST) to detect latent TB. Any active TB cases were identified through acid-fast smear tests. The data collected from the study participants was then analyzed.

Results

The results showed no significant difference in the size of TST between cancer and non-cancer patients (cases: median = 2 mm, IQR: 1-12; controls: median = 2 mm, IQR: 1-5; p = 0.09). The prevalence of latent TB was 27.1% in cancer patients and 20.7% in non-cancer patients, with no significant association identified between latent TB and malignancies (P-value = 0.176). Over a median follow-up of 4 years, mortality was significantly higher in cancer patients compared to controls (42.1% vs 1.8%; P< 0.001, OR = 40.64). Additionally, deceased patients exhibited a greater prevalence of latent TB (44% vs 19.3% in survivors; P< 0.001, OR = 3.28), and increased size of TST was associated with higher mortality risk among cancer patients.

Conclusion

In conclusion, this study emphasizes the need for vigilant latent TB screening in cancer patients, given the association between larger TST sizes and increased mortality risk. While no direct link between cancer type and latent TB was found, proactive TB management remains crucial, particularly for those undergoing immunosuppressive therapy.

Bacillus Calmette-Guérin vaccination induces a trained innate immunity phenotype in adults over 50 years of age: A randomized trial in Guinea-Bissau

BACKGROUND

The beneficial effects of Bacillus Calmette-Guérin (BCG) as an intervention against non-mycobacterial infections have been extensively studied in randomized trials. These non-specific effects have been linked to a heterologous increase of pro-inflammatory cytokine production by innate immune cells. It is unknown if BCG induces such responses in older individuals from TB-endemic countries.

METHODS

In a single-blinded trial in Guinea-Bissau, 40 adults over 50 years of age were randomized 1:1 in a block of 40 to intradermal injection of BCG-Japan (intervention) or solvent (placebo). Production of interleukin (IL)-1β, IL-6, IL-10, interferon (IFN)-γ and tumor necrosis factor (TNF)-α was measured by ELISA in supernatant of peripheral blood mononuclear cells stimulated with Mycobacterium tuberculosis and heterologous pathogens. The trial was registered at clinicaltrials.gov (NCT02953327).

FINDINGS

Between January 25 and March 7, 2017, 40 individuals were randomized. Two months after vaccination, BCG-Japan recipients (n = 11) had higher production of IFN-γ to M. tuberculosis stimulation (Geometric mean ratio (GMR): 3·91 [95 % Confidence Interval (CI), 1·53-9·96]) and increased release of the pro-inflammatory innate cytokines IL-1β, IL-6 and TNF-α to non-specific stimuli (GMR TNF-α: 1·47 [95 % CI, 0·98-2·19]) than their controls (n = 13). Both the specific and non-specific responses were more pronounced among those with a positive QuantiFERON at baseline.

INTERPRETATION

BCG-Japan can induce a trained immunity phenotype in older adults. These effects were particularly strong in previously M. tuberculosis exposed individuals. Future randomized trials are needed to determine BCG's potential to protect the older populations from infections-driven morbidity and mortality.

The Trend of Tuberculosis Case Notification Rates from 1995 to 2022 by Country Income and World Health Organization Region

Over the past 27 years, three major global TB control strategies have been implemented, and it is important at this stage to evaluate their impact on tuberculosis (TB) case notification rates (CNRs). This study, therefore, analyzed TB CNR trends from 1995 to 2022 across 208 countries and islands, using data from the WHO Global TB Programme database. Countries were classified by income level and population size based on World Bank criteria. The analysis revealed significant disparities in TB CNRs across income groups: Low-income, lower-middle-income, and upper-middle-income countries consistently reported higher CNRs compared to high-income countries. Regional analysis further demonstrated notable variations influenced by both economic and geographical factors. These findings reaffirm the strong link between TB and poverty, underscoring the need for a holistic approach to combat the disease. Efforts must extend beyond enhancing health care access and delivery to addressing the social determinants that drive TB transmission and progression.

Analysis of the c.1135G > A, c.1993A > G, c.2059T > C TAP2 gene variants and their relationship with latent tuberculosis infection in Mexico

Tuberculosis (TB) is a worldwide public health problem with 10.6 million people falling ill and 1.5 million deaths every year. Latent tuberculosis infection (LTBI) is a condition in which an individual has been infected with Mycobacterium tuberculosis (Mtb) but does not show clinical signs and symptoms. The transporter associated with antigen processing (TAP2) protein plays a fundamental role in the immune response promoting the clearance of intracellular pathogens, such as Mtb. Our study aimed to determine the association between c.1135G > A (rs1800454), c.1993A > G (rs241447) and c.2059 T > C (rs241448) TAP2 gene variants with LTBI susceptibility. In this case-control study, 180 individuals (90 were LTBI-positive and 90 were controls) from shelters were analyzed. Genotyping of the polymorphisms was performed using the Applied Biosystems Step One Thermal Cycler Real-Time PCR allelic discrimination technology. The haplotypic analyses were performed with the Arlequin 3.5 software. The G allele (OR = 1.732, CI = 1.125-2.667, p = 0.012) and AG genotype of the c.1993A > G variant (p=<0.001) were associated with susceptibility to LTBI (p=<0.001), as well as the GAT, AAT, AAC, AGT haplotypes (p=<0.001). The c.1135G > A and c.2059 T > C variants were not associated with LTBI risk.

Epidemiology of Latent Tuberculosis in Moroccan Healthcare Workers: Prevalence Patterns and Predisposing Factors

BACKGROUND

Among occupational hazards in healthcare settings, latent tuberculosis infection (LTBI) ranks as a major concern, particularly threatening healthcare workers (HCWs) in nations grappling with intermediate to high tuberculosis (TB) rates. Our study was conducted in Morocco, a country characterized by widespread Bacillus Calmette-Guérin (BCG) vaccination and a moderate TB burden of 93 cases per 100,000 inhabitants in 2022. We examined both the prevalence of LTBI among Moroccan HCWs and its various risk factors.

METHODS

A cross-sectional study was conducted from August 2022 to October 2024 in two Moroccan hospitals. One hundred forty-seven HCWs were recruited and screened for LTBI using the QuantiFERON-TB Gold In-Tube (QFT-GIT) test. Data on demographics, occupational characteristics, and potential risk factors were collected through standardized questionnaires. Statistical analysis included univariate and multivariate logistic regression to identify factors associated with LTBI.

RESULTS

The overall prevalence of LTBI was 32.65% (48/147). Multivariate analysis identified several independent risk factors: male gender (OR: 2.84; 95% CI: 1.54-5.22; p<0.001), age above 50 years (OR: 4.58; 95% CI: 1.50-13.90; p=0.007), smoking status (OR: 4.07; 95% CI: 1.63-10.14; p=0.003), and family history of TB (OR: 4.71; 95% CI: 1.33-16.65; p=0.016). Notably, neither specific work areas nor job categories were identified as significant risk factors in the final multivariate model.

CONCLUSIONS

The observed LTBI prevalence among HCWs in Morocco demonstrates concordance with epidemiological data from comparable intermediate-burden nations. The elucidation of predisposing factors, with particular emphasis on non-occupational determinants, underscores the imperative for implementing systematic surveillance protocols and World Health Organization (WHO)-sanctioned infection prevention measures within healthcare facilities. These epidemiological findings provide an empirical foundation for the formulation and optimization of TB control strategies specifically tailored to the occupational health needs of Morocco's healthcare workforce.

A multistage Sendai virus vaccine incorporating latency-associated antigens induces protection against acute and latent tuberculosis

One-quarter of the world's population is infected with Mycobacterium tuberculosis (Mtb). After initial exposure, more immune-competent persons develop asymptomatic latent tuberculosis infection (LTBI) but not active diseases, creates an extensive reservoir at risk of developing active tuberculosis. Previously, we constructed a novel recombinant Sendai virus (SeV)-vectored vaccine encoding two dominant antigens of Mtb, which elicited immune protection against acute Mtb infection. In this study, nine Mtb latency-associated antigens were screened as potential supplementary vaccine candidate antigens, and three antigens (Rv2029c, Rv2028c, and Rv3126c) were selected based on their immune-therapeutic effect in mice, and their elevated immune responses in LTBI human populations. Then, a recombinant SeV-vectored vaccine, termed SeV986A, that expresses three latency-associated antigens and Ag85A was constructed. In murine models, the doses, titers, and inoculation sites of SeV986A were optimized, and its immunogenicity in BCG-primed and BCG-naive mice were determined. Enhanced immune protection against the Mtb challenge was shown in both acute-infection and latent-infection murine models. The expression levels of several T-cell exhaustion markers were significantly lower in the SeV986A-vaccinated group, suggesting that the expression of latency-associated antigens inhibited the T-cell exhaustion process in LTBI infection. Hence, the multistage quarter-antigenic SeV986A vaccine holds considerable promise as a novel post-exposure prophylaxis vaccine against tuberculosis.

Mathematical modeling suggests heterogeneous replication of Mycobacterium tuberculosis in rabbits

Tuberculosis (TB), the disease caused by Mycobacterium tuberculosis (Mtb), remains a major health problem with 10.6 million cases of the disease and 1.6 million deaths in 2021. It is well understood that pulmonary TB is due to Mtb growth in the lung but quantitative estimates of rates of Mtb replication and death in lungs of patients or animals such as monkeys or rabbits remain largely unknown. We performed experiments with rabbits infected with a novel, virulent clinical Mtb isolate of the Beijing lineage, HN878, carrying an unstable plasmid pBP10. In our in vitro experiments we found that pBP10 is more stable in HN878 strain than in a more commonly used laboratory-adapted Mtb strain H37Rv (the segregation coefficient being s = 0.10 in HN878 vs. s = 0.18 in H37Rv). Interestingly, the kinetics of plasmid-bearing bacteria in lungs of Mtb-infected rabbits did not follow an expected monotonic decline; the percent of plasmid-bearing cells increased between 28 and 56 days post-infection and remained stable between 84 and 112 days post-infection despite a large increase in bacterial numbers in the lung at late time points. Mathematical modeling suggested that such a non-monotonic change in the percent of plasmid-bearing cells can be explained if the lung Mtb population consists of several (at least 2) sub-populations with different replication/death kinetics: one major population expanding early and being controlled/eliminated, while another, a smaller population expanding at later times causing a counterintuitive increase in the percent of plasmid-bearing cells. Importantly, a model with one kinetically homogeneous Mtb population could not explain the data including when the model was run stochastically. Given that in rabbits HN878 strain forms well circumscribed granulomas, our results suggest independent bacterial dynamics in subsets of such granulomas. Our model predictions can be tested in future experiments in which HN878-pBP10 dynamics in individual granulomas is followed over time. Taken together, our new data and mathematical modeling-based analyses illustrate differences in Mtb dynamics in mice and rabbits confirming a perhaps somewhat obvious observation that "rabbits are not mice".

Adverse drug reactions following treatment of latent tuberculosis infection: a linked national tuberculosis surveillance with claims database

BACKGROUND/AIMS

Few real-world studies explored factors associated with latent tuberculosis infection (LTBI) treatment-related adverse drug reactions (ADRs). This study evaluate ADRs that lead to the discontinuation of LTBI treatment and identify the associated factors, including age groups and drug regimens.

METHODS

Using the Korean national tuberculosis registry and HHC investigation database linked to the National Health Insurance Service claims database, we examined treatment discontinuation due to ADRs among HHCs on LTBI treatment from January 2015 to December 2018. Multivariable logistic regression analysis was conducted to examine factors associated with ADRs, including demographics, LTBI treatment, comorbidities, and steroid use.

RESULTS

Among 11,913 participants initiated LTBI treatment, 633 participants (5.3%) discontinued treatment due to ADRs. The primary contributors to discontinuation were adverse skin reactions (2.0%) and abnormal liver function (1.9%). Risk associated with ADRs and abnormal liver function showed age-related increase, except for the age group 66-75 (adjusted odds ratio [AOR] 3.82, 95% confidence interval [CI] 2.31-6.31) which reported lower OR to that of age group 36-65 (AOR 4.38, 95% CI 3.09-6.21). Three months isoniazid/rifampin and 4 months rifampin exhibited a lower odds of ADRs and abnormal liver function when compared to 6-9 months isoniazid.

CONCLUSION

We discovered the real-world prevalence of LTBI treatment discontinuation due to ADRs among HHCs. Our findings suggest a notably increased odds of ADRs resulting in discontinuation with age of 76 years or above, emphasizing careful attention when prescribing LTBI treatment in this population. Further studies are warranted to validate these results.

Cost-effectiveness of screening with transcriptional signatures for incipient TB among U.S. migrants

Introduction

Host-response-based transcriptional signatures (HrTS) have been developed to identify "incipient tuberculosis (TB)". No study has reported the cost-effectiveness of HrTS for post-arrival migrant screening programs in low-incidence countries.

Objectives

To assess the potential health impact and cost-effectiveness of HrTS for post-arrival TB infection screening among new migrants in the United States.

Methods

We used a discrete-event simulation model to compare four strategies: (1) no screening for TB infection or incipient TB; (2) 'IGRA-only', screen all with interferon gamma release assay (IGRA), provide TB preventive treatment for IGRA-positives; (3) 'IGRA-HrTS', screen all with IGRA followed by HrTS for IGRA-positives, provide incipient TB treatment for individuals testing positive with both tests; and (4) 'HrTS-only', screen all with HrTS, provide incipient TB treatment for HrTS-positives. We assessed outcomes over the lifetime of migrants entering the U.S. in 2019, assuming HrTS met the WHO Target Product Profile (TPP) optimal criteria. We conducted sensitivity analyses to evaluate the robustness of results.

Results

The IGRA-only strategy dominated the HrTS-based strategies under both healthcare sector and societal perspectives, with an incremental cost-effectiveness ratio of $78,943 and $89,431 per quality-adjusted life-years (QALY) gained, respectively. This conclusion was robust to varying costs ($15-300) and characteristics of HrTS, and the willingness-to-pay threshold ($30,000-150,000/ QALY gained), but sensitive to the rate of decline in TB progression risk after U.S. entry.

Conclusions

Our findings suggest that HrTS meeting the WHO TPP is unlikely to be a cost-effective component of post-arrival screening for migrants entering the U.S.

Mathematical modeling suggests heterogeneous replication of Mycobacterium tuberculosis in rabbits

Tuberculosis (TB), the disease caused by Mycobacterium tuberculosis (Mtb), remains a major health problem with 10.6 million cases of the disease and 1.6 million deaths in 2021. It is well understood that pulmonary TB is due to Mtb growth in the lung but quantitative estimates of rates of Mtb replication and death in lungs of patients or animals such as monkeys or rabbits remain largely unknown. We performed experiments with rabbits infected with a novel, virulent clinical Mtb isolate of the Beijing lineage, HN878, carrying an unstable plasmid pBP10. In our in vitro experiments we found that pBP10 is more stable in HN878 strain than in a more commonly used laboratory-adapted Mtb strain H37Rv (the segregation coefficient being s = 0.10 in HN878 vs. s = 0.18 in H37Rv). Interestingly, the kinetics of plasmid-bearing bacteria in lungs of Mtb-infected rabbits did not follow an expected monotonic decline; the percent of plasmid-bearing cells increased between 28 and 56 days post-infection and remained stable between 84 and 112 days post-infection despite a large increase in bacterial numbers in the lung at late time points. Mathematical modeling suggested that such a non-monotonic change in the percent of plasmid-bearing cells can be explained if the lung Mtb population consists of several (at least 2) sub-populations with different replication/death kinetics: one major population expanding early and being controlled/eliminated, while another, a smaller population expanding at later times causing a counterintuitive increase in the percent of plasmid-bearing cells. Importantly, a model with one kinetically homogeneous Mtb population could not explain the data including when the model was run stochastically. Given that in rabbits HN878 strain forms well circumscribed granulomas, our results suggest independent bacterial dynamics in subsets of such granulomas. Our model predictions can be tested in future experiments in which HN878-pBP10 dynamics in individual granulomas is followed over time. Taken together, our new data and mathematical modeling-based analyses illustrate differences in Mtb dynamics in mice and rabbits confirming a perhaps somewhat obvious observation that "rabbits are not mice".

Magnitude and Determinants of Latent Tuberculosis Among Inmates of Saudi Correctional Facilities: A Cross-Sectional Study

Purpose

To estimate the prevalence and determinants of latent tuberculosis (LTBI) among inmates of four correctional facilities in Saudi Arabia.

Methods

This is a retrospective review of health records. All inmates of four correctional facilities in Saudi Arabia were screened for tuberculosis in 2022. Their LTBI status was defined as more than 10mm Mantoux test result and negative X-ray chest result. The prevalence of LTBI and their determinants like age, gender, country of origin, location of the prison, and human immunodeficiency viruses (HIV) status were studied.

Results

We reviewed screening data of 10,042 inmates in four Saudi prisons. The prevalence of LTBI was 7.4%. The risk difference of LTBI was significantly higher in males compared to female inmates (P < 0.001). The highest prevalence of LTBI was noticed among males (7.7%), those older than 60 years old (26.9%), and African expatriates (12.1%). None of the female inmates or those with HIV had LTBI. The binomial regression analysis revealed a highly significant effect of older age on the risk of having LTBI.

Conclusion

The prevalence of LTBI was low among inmates at Saudi correctional facilities. The males, old age, and persons from African and Asian countries had a higher risk of LTBI. The prevalence of LTBI among inmates of Saudi prisons could be predicted by knowing their age group.

Persistent Mycobacterium tuberculosis bioaerosol release in a tuberculosis-endemic setting

Pioneering studies linking symptomatic disease and cough-mediated Mycobacterium tuberculosis (Mtb) release established the infectious origin of tuberculosis (TB), simultaneously informing the notion that pathology is a prerequisite for Mtb transmission. Our recent work has challenged this assumption: by sampling TB clinic attendees, we detected equivalent release of Mtb-containing bioaerosols by confirmed TB patients and individuals not receiving a TB diagnosis and observed time-dependent reduction in Mtb bioaerosol positivity during 6-month follow-up of both cohorts, irrespective of anti-TB chemotherapy. Now, we report widespread Mtb release in our TB-endemic setting: of 89 randomly recruited community members, 79.8% (71/89) produced Mtb-containing bioaerosols independently of QuantiFERON status, a standard test for Mtb exposure. Moreover, during 2-month longitudinal sampling, only 2% (1/50) were serially Mtb bioaerosol negative. These results necessitate a reframing of the prevailing paradigm of Mtb transmission and TB etiology, perhaps explaining the historical inability to elucidate Mtb transmission networks in TB-endemic regions.

A regression predictive model for QuantiFERON-TB Gold Plus® indeterminate results in immunosuppressed patients

Background

Screening for latent tuberculosis infection using Interferon-Gamma Release Assays is a routine procedure prior to the initiation of anti-tumor necrosis factor (TNF) biotherapy or immunosuppressive therapy. However, indeterminate results are relatively frequent and are an obstacle to treatment initiation.

Aim

The aim of this cross-sectional study was to estimate the frequency of indeterminate QuantiFERON-TB Gold Plus® test results in Tunisian patients, and to analyze the potential clinico-biological risk factors associated with these indeterminate results.

Methods

Whole blood samples from 712 patients being monitored for autoimmune diseases and candidates for anti-TNF biotherapy or switch of immunosuppressive therapy were used to screen for latent tuberculosis infection using the QuantiFERON-TB Gold Plus® test. Based on literature background, the following variables were tested for the association with indeterminate results: gender, age, diabetes, immunosuppressive drugs, lymphocyte count, Neutrophil-to-lymphocyte ratio, serum albumin, and estimated glomerular filtration rate.

Results

The QuantiFERON-TB Gold Plus® test was negative in 572 (80.3%) patients, positive in 106 (14.9%), and indeterminate in 34 (4.8%) cases. Positive results were significantly associated with a family history of confirmed and treated tuberculosis, OR (95% CI) = 52 (20.2-134.3). The use of immunosuppressive drugs and duration of treatment were significantly associated with the occurrence of indeterminate results: OR (95% CI) = 24.5 (5.8-103) and OR (95% CI) = 1.004 (1.002-1.007), respectively. Biologically, lymphopenia, hypoalbuminemia, and decreased estimated glomerular filtration rate were significant risk factors for indeterminate results: p = 5 E-6, p = 4.3 E-4, and p = 0.002, respectively. Thus, a multiple logistic regression model based on these three biological parameters enabled us to develop a predictive score for indeterminate results with a sensitivity of 91.2% and a specificity of 99.9%, AUC = 0.9964 (0.9917-1), p = 2.8 E-52.

Conclusion

Immunosuppressive therapy, lymphopenia, hypoalbuminemia, and kidney failure appeared to be risk factors for indeterminate QuantiFERON-TB Gold Plus® results.

Exploring expression levels of the cGAS-STING pathway genes in peripheral blood mononuclear cells of spinal tuberculosis patients

BACKGROUND

This study aimed to investigate the differential expression levels of the cGAS-STING pathway in peripheral blood mononuclear cells (PBMCs) of spinal tuberculosis (TB) patients with different progression and its feasibility as a diagnostic marker.

METHODS

Peripheral blood and medical records of 25 patients with spinal TB and 10 healthy individuals, were prospectively collected and analyzed. PBMCs and serum were extracted from peripheral blood and the expression levels of the cGAS-STING pathway in PBMCs were measured by real-time PCR (RT-PCR) and serum interferon β (IFN-β) expression levels were measured by enzyme-linked immunosorbent assay (ELISA). The expression of Interferon regulatory Factor 3 (IRF3) in PBMCs was measured using western blot. Statistical analysis was performed using the SPSS 26.0 statistical package.

RESULTS

The results showed that the expression level of the TANK-binding kinase 1 (TBK1) and IRF3 was significantly higher in PBMCs (P < 0.05), in patients with active lesions than in patients with stable lesions. The serum concentration of IFN-β was significantly higher in patients with active lesions (P = 0.028). Compared with healthy individuals, the expression level of the cGAS-STING pathway was elevated in PBMCs of TB patients (P < 0.05), and the difference in the expression level of IFN-β was not statistically significant (P > 0.05), and the serum IFN-β concentration was elevated (P < 0.05). The calculated AUC values for TBK1 and IRF3 in PBMCs, IFN-β in serum and erythrocyte sedimentation rate (ESR) to distinguish between patients with active and stable lesions were 0.732, 0.714, 0.839, and 0.714 respectively.

CONCLUSIONS

The expression level of TBK1 and IRF3 in PBMCs, and IFN-β in the serum of patients with spinal TB is positively correlated with disease activity. TBK1 has higher specificity and IFN-β in serum has higher sensitivity when used to differentiate between patients with active and stable lesions.

Disseminated MDR-TB missed in a patient treated with TNF inhibitor

A previously healthy man developed pulmonary symptoms 2 weeks after starting treatment with a tumour necrosis factor (TNF) inhibitor. A negative interferon-gamma release assay (IGRA) test was obtained prior to TNF inhibitor exposure, without consideration of the fact that the patient was already immunosuppressed and had a previous positive IGRA test 17 months earlier. The patient was treated for pneumonia twice but did not achieve remission. His physical health progressively deteriorated over the following months. Malignancy was suspected but not found. Eight months after the onset of symptoms, Mycobacterium tuberculosis was found in samples from mediastinal lymph nodes, and the patient was diagnosed with multidrug-resistant tuberculosis (MDR-TB).This case illustrates the diagnostic challenge of TB, the need to raise awareness of the increased risk of TB in patients treated with TNF inhibitors and the need to increase knowledge regarding the effect of immunosuppressive agents on IGRA tests.

Toll-Like Receptor Genes and Risk of Latent Tuberculosis Infection in People Infected with HIV-1

The purpose of this study was to determine the contribution of genetic factors, i.e., the level of expression and polymorphisms of Toll-like receptors (TLR), to the susceptibility of latent tuberculosis infection in a Russian cohort of individuals infected with HIV. The patients (n = 317) with confirmed HIV infection were divided into two groups according to the results of the STANDARD E TB-Feron test: 63 cases with a latent TB infection and 274 controls without LTBI. Total DNA and RNA were isolated from whole-blood samples. SNP genotyping and expression levels of five TLR genes (TLR1, TLR2, TLR4, TLR6, and TLR8) were determined by means of real-time PCR. There were no significant differences in the expression levels of the TLRs between the case and control groups. In addition, we did not observe any significant association between the analyzed SNPs and the susceptibility of Latent tuberculosis infection (LTBI) in patients with HIV. However, patients from an entire cohort with the rs4986790-GG (TLR4) and rs5743708-GG (TLR2) genotypes were characterized by lower CD4 T-cell counts compared to carriers of alternative alleles. Moreover, we found a significant risk of a hazardous drop in the CD4 T-cell count below 350 cells/mm3 associated with the rs4986790-G (TLR4) allele. Latent tuberculosis infection in individuals infected with HIV does not significantly modify the level of TLR gene expression.

HBHA induces IL-10 from CD4+ T cells in patients with active tuberculosis but IFN-γ and IL-17 from individuals with Mycobacterium tuberculosis infection

Background

To effectively control tuberculosis (TB), it is crucial to distinguish between active TB disease and latent TB infection (LTBI) to provide appropriate treatment. However, no such tests are currently available. Immune responses associated with active TB and LTBI are dynamic and exhibit distinct patterns. Comparing these differences is crucial for developing new diagnostic methods and understanding the etiology of TB. This study aimed to investigate the relationship between pro- and anti-inflammatory CD4+ cytokine production following stimulation with two types of latency-associated Mycobacterium tuberculosis (M.tb) antigens to allow differentiation between active TB and LTBI.

Methods

Cryopreserved PBMCs from patients with active TB disease or LTBI were stimulated overnight with replication-related antigen [ESAT-6/CFP-10 (E/C)] or two latency-associated antigens [heparin-binding hemagglutinin (HBHA) and alpha-crystallin-like protein (Acr)]. Responses were analyzed using multiparameter flow cytometry: active TB disease (n=15), LTBI (n=15) and ELISA: active TB disease (n=26) or LTBI (n=27).

Results

CD4+ central memory T cells (Tcm) specific to E/C and CD4+ effector memory T cells specific to Acr and HBHA were higher in LTBI than in TB patients. IFN-γ+Tcm and IL-17+ Tem cells was higher in the LTBI group (p= 0.012 and p=0.029 respectively), but IL-10+ Tcm was higher in the active TB group (p= 0.029) following HBHA stimulation. Additionally, following stimulation with HBHA, IL-10 production from CD4+ T cells was significantly elevated in patients with active TB compared to those with LTBI (p= 0.0038), while CD4+ T cell production of IL-17 and IFN-γ was significantly elevated in LTBI compared to active TB (p= 0.0076, p< 0.0001, respectively). HBHA also induced more CCR6+IL-17+CD4Tcells and IL-17+FoxP3+CD25+CD4Tcells in LTBI than in TB patients (P=0.026 and P=0.04, respectively). HBHA also induced higher levels of IFN-γ+IL-10+CD4+ T cells in patients with active TB (Pp=0.03) and higher levels of IFN-γ+IL-17+ CD4+ T cells in those with LTBI (p=0.04). HBHA-specific cytokine production measured using ELISA showed higher levels of IFN-γ in participants with LTBI (P=0.004) and higher levels of IL-10 in those with active TB (P=0.04).

Conclusion

Stimulation with HBHA and measurement of CD4+ T cell production of IFN-γ, IL-10, and IL-17 could potentially differentiate active TB from LTBI. The characteristics of cytokine-expressing cells induced by HBHA also differed between participants with active TB and LTBI.

Influence of tuberculosis knowledge on acceptance of preventive treatment and the moderating role of tuberculosis stigma among China's general population: cross-sectional analysis

BACKGROUND

Preventive treatment of tuberculosis infection (TBI) is considered a crucial strategy to prevent and control tuberculosis (TB). However, the acceptance and completion rates of preventive therapy for TBI are still far from optimistic. Evidence is mounting that TB knowledge and stigma may have a substantial effect on acceptance of TBI treatment. This study aimed to explore the effect of stigma on the relationship between the level of TB knowledge and acceptance of TBI treatment.

METHODS

7017 general population were included in the study. We adjusted for the covariates at the individual. Stepwise logistic regression was used to examine the moderating role of TB stigma and also explore the association between TB knowledge and acceptance of TBI treatment.

RESULTS

The acceptance rate of TBI treatment among the respondents was 84.38% (n = 5921). Among respondents, a significant positive correlation between acceptance of TBI treatment and TB knowledge (OR = 1.096,95%CI = 1.073,1.118). Additionally, the association between TB knowledge and acceptance of TBI treatment was found to be moderated by TB stigma. In other words, TB stigma was found to weaken the impact of TB knowledge on acceptance of TBI treatment (OR = 0.994,95%CI = 0.991,0.996).

CONCLUSION

The findings of the study indicated that having a high level of awareness about TB can enhance the general population's acceptability of TBI treatment. TB stigma moderated this association; it weakened the relationship between TB knowledge and individuals' willingness to accept TBI treatment. To mitigate TB stigma and enhance the intention of individuals with TBI to accept preventive therapy, it is imperative to enhance TB-related health education.

Global, regional, and national burden of HIV-negative tuberculosis, 1990-2021: findings from the Global Burden of Disease Study 2021

BACKGROUND

Tuberculosis (TB) is a major infectious disease with significant public health implications. Its widespread transmission, prolonged treatment duration, notable side effects, and high mortality rate pose severe challenges. This study examines the epidemiological characteristics of TB globally and across major regions, providing a scientific basis for enhancing TB prevention and control measures worldwide.

METHODS

The ecological study used data from the Global Burden of Disease (GBD) Study 2021. It assessed new incidence cases, deaths, disability-adjusted life years (DALYs), and trends in age-standardized incidence rates (ASIRs), mortality rates (ASMRs), and DALY rates for drug-susceptible tuberculosis (DS-TB), multidrug-resistant tuberculosis (MDR-TB), and extensively drug-resistant tuberculosis (XDR-TB) from 1990 to 2021. A Bayesian age-period-cohort model was applied to project ASIR and ASMR.

RESULTS

In 2021, the global ASIR for all HIV-negative TB was 103.00 per 100,000 population [95% uncertainty interval (UI): 92.21, 114.91 per 100,000 population], declining by 0.40% (95% UI: - 0.43, - 0.38%) compared to 1990. The global ASMR was 13.96 per 100,000 population (95% UI: 12.61, 15.72 per 100,000 population), with a decline of 0.44% (95% UI: - 0.61, - 0.23%) since 1990. The global age-standardized DALY rate for HIV-negative TB was 580.26 per 100,000 population (95% UI: 522.37, 649.82 per 100,000 population), showing a decrease of 0.65% (95% UI: - 0.69, - 0.57 per 100,000 population) from 1990. The global ASIR of MDR-TB has not decreased since 2015, instead, it has shown a slow upward trend in recent years. The ASIR of XDR-TB has exhibited significant increase in the past 30 years. The projections indicate MDR-TB and XDR-TB are expected to see significant increases in both ASIR and ASMR from 2022 to 2035, highlighting the growing challenge of drug-resistant TB.

CONCLUSIONS

This study found that the ASIR of MDR-TB and XDR-TB has shown an upward trend in recent years. To reduce the TB burden, it is essential to enhance health infrastructure and increase funding in low-SDI regions. Developing highly efficient, accurate, and convenient diagnostic reagents, along with more effective therapeutic drugs, and improving public health education and community engagement, are crucial for curbing TB transmission.

Prevalence of tuberculosis infection among contacts of drug-resistant tuberculosis patients: A systematic review and meta-analysis

INTRODUCTION

Contact investigations with drug-susceptible tuberculosis (DS-TB) patients have demonstrated a high prevalence of tuberculosis infection (TBI). However, the prevalence of TBI among individuals in close contact with drug-resistant tuberculosis (DR-TB) patients is poorly understood. This systematic review and meta-analysis aimed to determine the prevalence of TBI among household and non-household contacts of DR-TB patients.

METHOD AND ANALYSIS

We searched five databases (Medline, Embase, Scopus, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL)) from inception to 2 June 2023. All studies that reported the prevalence of TBI among DR-TB contacts were included in the study. A random-effects meta-analysis was conducted to estimate the pooled prevalence of TBI with a 95% confidence interval (CI). Sub-group analyses were conducted using study characteristics as covariates.

RESULTS

Thirty studies involving 7659 study participants from 19 countries were included. The pooled prevalence of TBI among DR-TB contacts was 36.52% (95% CI: 30.27-42.77). The sub-group analysis showed considerable heterogeneity in the estimates, with the highest prevalence reported in Southeast Asia (80.74%; 95% CI: 74.09-87.39), household contacts (38.60%; 95% CI: 30.07-47.14), lower-middle-income countries (LMICs) (54.72; 95% CI: 35.90, 73.55), children (43.27%; 95% CI: 25.50, 61.04), and studies conducted between 2004 and 2012 (45.10; 95% CI: 32.44, 57.76).

CONCLUSION

The prevalence of TBI among DR-TB contacts was high, with substantial regional variations. Further research is needed to determine the drug susceptibility status of TBI in DR-TB contacts.

PROTOCOL REGISTRATION

The protocol is registered in PROSPERO (CRD42023390339).

The role of chest X-rays when screening for latent tuberculosis infection in patients with inflammatory bowel disease before starting biologic treatment

BACKGROUND

Guidelines generally recommend a combination of immunological assays and chest X-ray imaging (CXR) when screening for latent tuberculosis infection (LTBI) prior to biologic treatment in inflammatory bowel disease (IBD).

OBJECTIVE

To investigate whether CXR identify patients with suspected LTBI/TB who were not identified with QuantiFERON tests (QFT) when screening for LTBI/TB before starting biologic treatment in IBD patients.

METHODS

Single-center, retrospective cohort study of patients with inflammatory bowel disease who had a QFT and a CXR prior to initiation of biologic treatment in a 5-year period (October 1st, 2017 to September 30th, 2022).

RESULTS

520 patients (56% female, mean age 40.1 years) were included. The majority had none or few risk factors for TB (as reflected by the demographic characteristics) but some risk factors for having false negative QFT results (concurrent glucocorticoid treatment and inflammatory activity). QFT results were positive in 8 patients (1.5%), inconclusive in 18 (3.5%) and negative in 494 (95.0%). Only 1 patient (0.19%) had CXR findings suspicious of LTBI. This patient also had a positive QFT and was subsequently diagnosed with active TB. All patients with negative or inconclusive QFT had CXR without any findings suggesting LTBI/TB. One patient developed active TB after having initiated biologic treatment in spite of having negative QFT and a normal CXR at screening.

CONCLUSION

In a population with low risk of TB, the benefits of supplementing the QFT with a CXR are limited and are unlikely to outweigh the cost in both patient test-burden, radioactive exposure, and economic resources.

Economic evaluation of diagnosis and treatment for latent tuberculosis infection among contacts of pulmonary tuberculosis patients in Thailand

Currently, interferon-gamma release assay (IGRA) is costly and not included as latent tuberculosis infection (LTBI) screening test strategy in Thailand's Universal Coverage Scheme (UCS) benefit package. The objective of this study was to assess the cost-utility of LTBI screening strategies among tuberculosis (TB) contacts in Thailand. A hybrid decision tree and Markov model was developed to compare the lifetime costs and health outcomes of tuberculin skin test (TST) and IGRA, in comparison to no screening, based on a societal perspective. Health outcomes were the total number of TB cases averted and quality-adjusted life years (QALYs), with results presented as an incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analyses were performed to explore uncertainties in all parameters. The ICER of TST compared with no screening was 27,645 baht per QALY gained, while that of IGRA compared to TST was 851,030 baht per QALY gained. In a cohort of 1000 TB contacts, both TST and IGRA strategies could avert 282 and 283 TB cases, respectively. At the Thai societal willingness-to-pay threshold of 160,000 baht per QALY gained, TST was deemed cost-effective, whereas IGRA would not be cost-effective, unless the cost of IGRA was reduced to 1,434 baht per test.

Tuberculosis research advances and future trends: A bibliometric knowledge mapping approach

The Gulf Cooperation Council (GCC) countries are more vulnerable to many transmissible diseases, including tuberculosis (TB). This study is to identify the scientific publications related to TB in the GCC countries using topic modeling and co-word analysis. A bibliometric analytic study. The R-package, VOSviewer software, IBM SPPS, and Scopus Analytics were used to analyze performance, hotspots, knowledge structure, thematic evolution, trend topics, and inter-gulf and international cooperation on TB in the past 30 years (1993-2022). A total of 1999 publications associated with research on GCC-TB were published. The annual growth rate of documents was 7.76%. Saudi Arabia is the most highly published, followed by the United Arab Emirates, Kuwait, Qatar, Oman, and Bahrain. The most-cited GC country is Kingdom Saudi Arabia, followed by Kuwait. One hundred sixty research institutions contributed to the dissemination of TB-related knowledge in the GCC, where the highest publishing organizations were King Saud University (Kingdom Saudi Arabia; n = 518). The number of publications related to TB is high in GCC Countries. The current tendencies indicated that GCC scholars are increasingly focused on deep learning, chest X-ray, molecular docking, comorbid covid-19, risk factors, and Mycobacterium bovis.

Epidemiology and Treatment Outcomes of Tuberculosis With Chronic Hepatitis B Infection-California, 2016-2020

BACKGROUND

Improved epidemiologic and treatment data for active tuberculosis (TB) with chronic hepatitis B virus (cHBV) infection might inform and encourage screening and vaccination programs focused on persons at risk of having both conditions.

METHODS

We matched the California Department of Public Health TB registry during 2016-2020 to the cHBV registry using probabilistic matching algorithms. We used chi-square analysis to compare the characteristics of persons with TB and cHBV with those with TB only. We compared TB treatment outcomes between these groups using modified Poisson regression models. We calculated the time between reporting of TB and cHBV diagnoses for those with both conditions.

RESULTS

We identified 8435 persons with TB, including 316 (3.7%) with cHBV. Among persons with TB and cHBV, 256 (81.0%) were non-US-born Asian versus 4186 (51.6%) with TB only (P < .0001). End-stage renal disease (26 [8.2%] vs 322 [4.0%]; P < .001) and HIV (21 [6.7%] vs 247 [3.0%]; P = .02) were more frequent among those with TB and cHBV compared with those with TB only. Among those with both conditions, 35 (11.1%) had TB diagnosed >60 days before cHBV (median, 363 days) and 220 (69.6%) had TB diagnosed >60 days after cHBV (median, 3411 days).

CONCLUSIONS

Persons with TB and cHBV were found more frequently in certain groups compared with TB only, and infrequently had their conditions diagnosed together. This highlights an opportunity to improve screening and treatment of TB and cHBV in those at high risk for coinfection.

Optimizing the cascade of prevention to protect people from tuberculosis: A potential game changer for reducing global tuberculosis incidence

The provision of tuberculosis preventive treatment is one of the critical interventions to reduce tuberculosis incidence and ultimately eliminate the disease, yet we still miss appropriate tools for an impactful intervention and treatment coverage remains low. We used recent data, epidemiological estimates, and research findings to analyze the challenges of each step of the cascade of tuberculosis prevention that currently delay the strategy implementation. We addressed research gaps and implementation bottlenecks that withhold key actions in tuberculosis case finding, testing for tuberculosis infection, provision of preventive treatment with safer, shorter regimens and supporting people to complete their treatment. Empowering communities to generate demand for preventive therapy and other prevention services in a holistic manner and providing adequate financial support to sustain implementation are essential requirements. The adoption of an effective, universal monitoring and evaluation system is a prerequisite to provide general and granular insight, and to steer progress of the tuberculosis infection strategy at global and local level.

Integrative and comparative genomic analyses of mammalian macrophage responses to intracellular mycobacterial pathogens

Mycobacterium tuberculosis, the causative agent of human tuberculosis (hTB), is a close evolutionary relative of Mycobacterium bovis, which causes bovine tuberculosis (bTB), one of the most damaging infectious diseases to livestock agriculture. Previous studies have shown that the pathogenesis of bTB disease is comparable to hTB disease, and that the bovine and human alveolar macrophage (bAM and hAM, respectively) transcriptomes are extensively reprogrammed in response to infection with these intracellular mycobacterial pathogens. In this study, a multi-omics integrative approach was applied with functional genomics and GWAS data sets across the two primary hosts (Bos taurus and Homo sapiens) and both pathogens (M. bovis and M. tuberculosis). Four different experimental infection groups were used: 1) bAM infected with M. bovis, 2) bAM infected with M. tuberculosis, 3) hAM infected with M. tuberculosis, and 4) human monocyte-derived macrophages (hMDM) infected with M. tuberculosis. RNA-seq data from these experiments 24 h post-infection (24 hpi) was analysed using three computational pipelines: 1) differentially expressed genes, 2) differential gene expression interaction networks, and 3) combined pathway analysis. The results were integrated with high-resolution bovine and human GWAS data sets to detect novel quantitative trait loci (QTLs) for resistance to mycobacterial infection and resilience to disease. This revealed common and unique response macrophage pathways for both pathogens and identified 32 genes (12 bovine and 20 human) significantly enriched for SNPs associated with disease resistance, the majority of which encode key components of the NF-κB signalling pathway and that also drive formation of the granuloma.

Flow cytometry-based method using diversity of cytokine production differentiates between Mycobacterium tuberculosis infection and disease

Authors present a pilot study of the development of innovative flow cytometry-based assay with a potential for use in tuberculosis diagnostics. Currently available tests do not provide robust discrimination between latent tuberculosis infection (TBI) and tuberculosis disease (TB). The desired application is to distinguish between the two conditions by evaluating the production of a combination of three cytokines: IL-2 (interleukin-2), IFNɣ (interferon gamma) and TNFɑ (tumor necrosis factor alpha) in CD4+ and CD8+ T cells. The study was conducted on 68 participants, divided into two arms according to age (paediatric and adults). Each arm was further split into three categories (non-infection (NI), TBI, TB) based on the immune reaction to Mycobacterium tuberculosis (M.tb) after a close contact with pulmonary TB. Each blood sample was stimulated with specific M.tb antigens present in QuantiFERON tubes (TB1 and TB2). We inferred TBI or TB based on the predominant cytokine response of the CD4+ and/or CD8+ T cells. Significant differences were detected between the NI, TBI and the TB groups in TB1 in the CD4+TNFɑ+parameter in children. Along with IL-2, TNFɑ seems to be the most promising diagnostic marker in both CD4+and CD8+ T cells. However, more detailed analyses on larger cohorts are needed to confirm the observed tendencies.

Bioinformatics Study and Experimental Evaluation of miR-182, and miR-34 Expression Profiles in Tuberculosis and Lung Cancer

BACKGROUND

Lung cancer is one of the most dangerous cancers and tuberculosis is one of the deadliest infectious diseases in the world. Many studies have confirmed the connection between lung cancer and tuberculosis, and also the microRNAs (miRNAs) that play a major role in the development of these two diseases. This study aims to use different databases to find effective miRNAs and their role in different genes in lung and tuberculosis diseases. It also aims to determine the role of miR-34a and miR-182 in lung cancer and tuberculosis.

METHODS

Using the Gene Expression Omnibus (GEO) database, the influential miRNA databases were studied in the two diseases. Finally, considering bioinformatics results and literature studies, two miR-34a and miR-182 were selected. The role of these miRNAs and their target genes was carefully evaluated using bioinformatics. The expression of miRNAs in the plasma of patients with lung cancer and tuberculosis and healthy individuals was investigated.

RESULTS

According to the GEO database, miR-34a and miR-182 are miRNAs that affect tuberculosis and lung cancer. By checking the miRBase, miRcode, DIANA, miRDB, galaxy, Kyoto Encyclopedia of Genes and Genomes databases, the role of these miRNAs on genes and different molecular pathways and their effect on these miRNAs were mentioned. The results of the present study showed that the expression of miR-34a and miR-182 was lower than that of healthy people. The p-value for miR-182 was <0.0001 and for miR-34a was 0.3380.

CONCLUSION

Reducing the expression pattern of these miRNAs indicates their role in lung cancer and tuberculosis occurrence. Therefore, these miRNAs can be used as a biomarker for prognosis, diagnosis, and treatment methods.

Pharmacokinetics of standard versus high-dose rifampin for tuberculosis preventive treatment: A sub-study of the 2R2 randomized controlled trial

BACKGROUND

Pharmacokinetic data of rifampin, when used for tuberculosis preventive treatment (TPT) are not available. We aimed to describe the pharmacokinetics of rifampin used for TPT, at standard and higher doses, and to assess predictors of rifampin exposure.

METHODS

A pharmacokinetic sub-study was performed in Bandung, Indonesia among participants in the 2R2 randomized trial, which compared TPT regimens of 2 months of high-dose rifampin at 20 mg/kg/day (2R20) and 30 mg/kg/day (2R30), with 4 months of standard-dose rifampin at 10 mg/kg/day (4R10) in adolescents and adults. Intensive pharmacokinetic sampling was performed after 2-8 weeks of treatment. Pharmacokinetic parameters were assessed non-compartmentally. Total exposure (AUC0-24) and peak concentration (Cmax) between arms were compared using one-way ANOVA and Tukey's post-hoc tests. Multivariable linear regression analyses were used to assess predictors of AUC0-24 and Cmax.

RESULTS

We enrolled 51 participants in this study. In the 4R10, 2R20, and 2R30 arms, the geometric mean AUC0-24 was 68.0, 186.8, and 289.9 h⋅mg/L, and Cmax was 18.4, 36.7, and 54.4 mg/L, respectively; high interindividual variabilities were observed. Compared with the 4R10 arm, AUC0-24 and Cmax were significantly higher in the 2R20 and 2R30 arms (P < 0.001). Drug doses, body weight, and female sex were predictors of higher rifampin AUC0-24 and Cmax (P < 0.05). AUC0-24 and Cmax values were much higher than those previously reported in persons with TB disease.

CONCLUSIONS

Doubling and tripling the rifampin dose led to three- and four-fold higher exposure compared to standard dose. Pharmacokinetic/pharmacodynamic modelling and simulations are warranted to support trials of shortening the duration of TPT regimens with high-dose rifampin.

Performance of fine needle aspiration cytology and Ziehl-Neelsen staining technique in the diagnosis of tuberculosis lymphadenitis

INTRODUCTION

Proper diagnosis of tuberculosis (TB) lymphadenitis is critical for its treatment and prevention. Fine needle aspirate cytology (FNAC) is the mainstay method for the diagnosis of TB lymphadenitis in Ethiopia; however, the performance of FNAC has not been evaluated in the Eastern Region of Ethiopia. This study aimed to evaluate the performance of FNAC and Ziehl-Neelsen (ZN) staining compared with that of GeneXpert for the diagnosis of TB lymphadenitis.

METHODS

Fine needle aspiration (FNA) specimens collected from 291 patients suspected of having TB lymphadenitis were examined using FNAC, ZN, and GeneXpert to diagnose TB lymphadenitis. Gene-Xpert was considered the reference standard method for comparison. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and kappa coefficient were determined using SPSS version 25.

RESULTS

The sensitivity, specificity, PPV, and NPV of ZN for diagnosing TB lymphadenitis were 73.2%, 97.4%, 96.2%, and 80.1% respectively. There was poor agreement between ZN and GeneXpert (Kappa=-0.253). The sensitivity, specificity, PPV, and NPV of FNAC were 83.3%, 94.8%, 93.5%, and 86.3% respectively. There was moderate agreement between the FNAC and GeneXpert (Kappa = 0.785).

CONCLUSION

The fine needle aspiration cytology (FNAC) is a more sensitive test for the diagnosis of TB lymphadenitis than ZN. The FNAC showed a moderate agreement with the GeneXpert assay. This study recommends the FNA GeneXpert MTB/RIF test in preference to FNAC for the diagnosis of TB lymphadenitis to avoid a missed diagnosis of smear-negative TB lymphadenitis.

Epidemiology and antimicrobial resistance of Mycobacterium spp. in the United Arab Emirates: a retrospective analysis of 12 years of national antimicrobial resistance surveillance data

Introduction

The Eastern Mediterranean Regional Office (EMRO) region accounts for almost 8% of all global Mycobacterium tuberculosis (TB) cases, with TB incidence rates ranging from 1 per 100,000 per year in the United Arab Emirates (UAE) to 204 per 100,000 in Djibouti. The national surveillance data from the Middle East and North Africa (MENA) region on the epidemiology and antimicrobial resistance trends of TB, including MDR-TB remains scarce.

Methods

A retrospective 12-year analysis of N = 8,086 non-duplicate diagnostic Mycobacterium tuberculosis complex (MTB complex) isolates from the UAE was conducted. Data were generated through routine patient care during the 2010-2021 years, collected by trained personnel and reported by participating surveillance sites to the UAE National Antimicrobial Resistance (AMR) Surveillance program. Data analysis was conducted with WHONET, a windows-based microbiology laboratory database management software developed by the World Health Organization Collaborating Center for Surveillance of Antimicrobial Resistance, Boston, United States (https://whonet.org/).

Results

A total of 8,086 MTB-complex isolates were analyzed. MTB-complex was primarily isolated from respiratory samples (sputum 80.1%, broncho-alveolar lavage 4.6%, pleural fluid 4.1%). Inpatients accounted for 63.2%, including 1.3% from ICU. Nationality was known for 84.3% of patients, including 3.8% Emiratis. Of UAE non-nationals, 80.5% were from 110 countries, most of which were Asian countries. India accounted for 20.8%, Pakistan 13.6%, Philippines 12.7%, and Bangladesh 7.8%. Rifampicin-resistant MTB-complex isolates (RR-TB) were found in 2.8% of the isolates, resistance to isoniazid, streptomycin, pyrazinamide, and ethambutol, was 8.9, 6.9, 3.4 and 0.4%, respectively. A slightly increasing trend of resistance among MTB-complex was observed for rifampicin from 2.5% (2010) to 2.8% (2021).

Conclusion

Infections due to MTB-complex are relatively uncommon in the United Arab Emirates compared to other countries in the MENA region. Most TB patients in the UAE are of Asian origin, mainly from countries with a high prevalence of TB. Resistance to first line anti-tuberculous drugs is generally low, however increasing trends for MDR-TB mainly rifampicin linked resistance is a major concern. MDR-TB was not associated with a higher mortality, admission to ICU, or increased length of hospitalization as compared to non-MDR-TB.

Genetic and clinical predictors of rifapentine and isoniazid pharmacokinetics in paediatrics with tuberculosis infection

OBJECTIVES

Twelve weekly doses of rifapentine and isoniazid (3HP regimen) are recommended for TB preventive therapy in children with TB infection. However, they present with variability in the pharmacokinetic profiles. The current study aimed to develop a pharmacokinetic model of rifapentine and isoniazid in 12 children with TB infection using NONMEM.

METHODS

Ninety plasma and 41 urine samples were collected at Week 4 of treatment. Drug concentrations were measured using a validated HPLC-UV method. MassARRAY® SNP genotyping was used to investigate genetic factors, including P-glycoprotein (ABCB1), solute carrier organic anion transporter B1 (SLCO1B1), arylacetamide deacetylase (AADAC) and N-acetyl transferase (NAT2). Clinically relevant covariates were also analysed.

RESULTS

A two-compartment model for isoniazid and a one-compartment model for rifapentine with transit compartment absorption and first-order elimination were the best models for describing plasma and urine data. The estimated (relative standard error, RSE) of isoniazid non-renal clearance was 3.52 L·h-1 (23.1%), 2.91 L·h-1 (19.6%), and 2.58 L·h-1 (20.0%) in NAT2 rapid, intermediate and slow acetylators. A significant proportion of the unchanged isoniazid was cleared renally (2.7 L·h-1; 8.0%), while the unchanged rifapentine was cleared primarily through non-renal routes (0.681 L·h-1; 3.6%). Participants with the ABCB1 mutant allele had lower bioavailability of rifapentine, while food prolonged the mean transit time of isoniazid.

CONCLUSIONS

ABCB1 mutant allele carriers may require higher rifapentine doses; however, this must be confirmed in larger trials. Food did not affect overall exposure to isoniazid and only delayed absorption time.

Screening for Latent Tuberculosis Infection in People Living with HIV: TUBHIVIT Project, a Multicenter Italian Study

BACKGROUND

The coexistence of HIV infection and latent tuberculosis infection (LTBI) presents a significant public health concern due to the increased risk of tuberculosis (TB) reactivation and progression to active disease. The multicenter observational cohort study, TUBHIVIT, conducted in Italy from 2017 to 2023, aimed to assess the prevalence of LTBI among people living with HIV (PLHIV) and their outcomes following LTBI screening and therapy initiation.

METHODS

We performed a prospective study in five referral centers for HIV care in Italy. PLHIV who consented Tto participate underwent QuantiFERON-TB Gold Plus and clinical, microbiological, and radiological assessments to exclude subclinical tuberculosis, as opportune. PLHIV diagnosed with LTBI who started chemoprophylaxis were followed until the end of therapy.

RESULTS

A total of 1105 PLHIV were screened for LTBI using the QuantiFERON-TB Gold Plus test, revealing a prevalence of 3.4% of positive results (38/1105). Non-Italy-born individuals exhibited a significantly higher likelihood of testing positive. Thirty-one were diagnosed with LTBI, 1 showed active subclinical TB, and 6 were lost to follow-up before discriminating between latent and active TB. Among the PLHIV diagnosed with LTBI, 83.9% (26/31) started chemoprophylaxis. Most individuals received 6-9 months of isoniazid-based therapy. Of the 26 PLHIV commencing chemoprophylaxis, 18 (69.2%) completed the therapy, while 3 discontinued it and 5 were still on treatment at the time of the analysis. Adverse events were observed in two cases, while in one case the patient refused to continue the treatment.

Identification of novel inhibitors for trigger factor (TF) of M. tb: an in silico investigation

Trigger factor, as a chaperone protein, is required for survival of Mycobacterium tuberculosis (M.tb) in a stressed environment. This protein interacts with various partners in both the pre- and the post-translation processes, yet the crystal structures of the M.tb trigger factor remain unresolved. In this study, we developed a homology model of M.tb trigger factor to facilitate the discovery and design of inhibitors. To validate the model, we employed several methodologies, including Ramachandran plot and molecular dynamics simulations. The simulations showed a stable trajectory, indicating the accuracy of the model. The active site of M.tb Trigger Factor was identified based on site scores, and virtual screening of over 70,000 compounds led to the identification of two potential hits: HTS02984 (ethyl 2-(3-(4-fluorophenyl)ureido)-6-methyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate) and S06856 ((E)-N-(4-((2-(4-(tert-butyl)benzoyl)hydrazono)methyl)phenyl) acetamide). These compounds showed strong binding affinity and energy scores, and their chemical descriptors were evaluated. Our study provides a reliable computational model for M.tb Trigger Factor and identifies two potential inhibitors for this crucial protein, which could aid in the development of novel therapies against tuberculosis.Communicated by Ramaswamy H. Sarma.

Global tuberculosis disease and infection in systemic lupus erythematosus patients: A systematic review and meta-analysis

BACKGROUND

Tuberculosis (TB) is one of the most common infections among systemic lupus erythematosus (SLE) patients. We aimed to evaluate the global prevalence of TB infection and disease, its type, and medication risk factors in SLE patients.

METHODS

We searched PubMed, Science Direct, EBSCO, and Web of Science databases from inception to April 30, 2023, and included studies assessing TB among SLE patients. We estimated the prevalence of TB disease (including type of TB disease), TB infection, and SLE medication as TB risk factors. Meta-analysis was performed using Stata 14.2 and Review Manager 5.3.

RESULTS

Twenty-seven studies met the eligibility criteria. The global prevalence of TB disease was 4% (95% confidence interval (CI): 3-4%, n = 25) and TB infection was 18% (95% CI: 10-26%, n = 3). The pooled prevalence of pulmonary TB, extrapulmonary TB, and disseminated TB were 2% (95% CI: 2-3%, n = 20), 1% (95% CI: 1-2%, n = 17), and 1% (95% CI: 0-1%, n = 6), respectively. The 1-year cumulative glucocorticoid (GC) dose in SLE patients contracting TB was higher than in those without TB, having a mean difference of 2.56 (95% CI: 0.22-4.91, p < .00001, n = 3). The odd ratio of TB was 2.11 (95% CI: 1.01-4.41, p = .05, n = 3) in SLE patients receiving methylprednisolone (MP) pulse therapy as compared to those without MP pulse therapy. Other immunosuppressive agents were not significantly associated with TB.

CONCLUSION

TB prevalence in SLE was relatively high and associated with GC. Awareness of TB and lowering GC dose are warranted to alleviate the TB burden in SLE.

Prevalence, Risk Factors, and Result Features in the Detection of Latent Tuberculosis Infection in Thai Healthcare Workers Using QuantiFERON-TB Gold Plus

Introduction Latent tuberculosis infection (LTBI) is an enormous reservoir for tuberculosis (TB), and healthcare workers (HCWs) are at high risk for TB infection. QuantiFERON-TB Gold Plus (QFT-Plus) is an alternative to the tuberculin skin test for LTBI detection, but data on its application and LTBI detected by QFT-Plus in high TB burden countries are limited. This study aimed to determine the prevalence of LTBI and its risk factors, and to investigate the QFT-Plus results in Thai HCWs. Methods A cross-sectional analytical study was conducted among HCWs at a secondary care hospital in Health Region 5, Thailand. Eligible HCWs were enrolled and underwent QFT-Plus testing. Interferon-gamma (IFN-γ) values in tubes were analysed. The prevalence and associated risk factors for LTBI were assessed based on laboratory and sociodemographic data. Logistic regression analyses were applied to calculate odds ratios (OR, aOR) reported with 95% confidence intervals (CI). Results Of the 269 participants enrolled, their median age was 42 years and 93.31% (n = 251/269) were female. The majority (n = 178/269, 66.17%) were nurses or nurse assistants and 42.75% (n = 115/269) worked in the inpatient medical wards. Overall, the QFT-Plus results showed 110 (40.89%) positive with good agreement (93.68%; κ 0.87) and high correlation (Spearman's ρ 0.91) of IFN-γ concentrations in the two antigen tubes. A true difference in IFN-γ values for predicting a recent infection was found about 7.81% (n = 21/269). By univariate and multivariate analyses, the participants' age > 40 years (OR = 3.21, 95% CI: 1.84-5.64%; aOR = 2.05, 95% CI: 1.07-3.96%), and employment duration > 10 years (OR = 3.19, 95% CI: 1.66-6.37%; aOR = 2.34, 95% CI: 1.05-5.21%) were significantly associated with the increased risk of LTBI (p-value < 0.05). Conclusions The prevalence of LTBI among these HCWs was high, and the increased risk factors for LTBI according to QFT-Plus positivity were age over 40 years and working time in the hospital for more than 10 years. It is important to screen HCWs in this setting for LTBI, particularly those with long employment durations and older ages. The high prevalence of LTBI suggests that LTBI management, such as regular screening and treatment, should be considered together with strengthening preventive measures, especially in high-risk groups.

Persistent Mycobacterium tuberculosis bioaerosol release in a tuberculosis-endemic setting

Pioneering studies linking symptomatic disease and cough-mediated release of Mycobacterium tuberculosis (Mtb) established the infectious origin of tuberculosis (TB), simultaneously informing the pervasive notion that pathology is a prerequisite for Mtb transmission. Our prior work has challenged this assumption: by sampling TB clinic attendees, we detected equivalent release of Mtb-containing bioaerosols by confirmed TB patients and individuals not receiving a TB diagnosis, and we demonstrated a time-dependent reduction in Mtb bioaerosol positivity during six-months' follow-up, irrespective of anti-TB chemotherapy. Now, by extending bioaerosol sampling to a randomly selected community cohort, we show that Mtb release is common in a TB-endemic setting: of 89 participants, 79.8% (71/89) produced Mtb bioaerosols independently of QuantiFERON-TB Gold status, a standard test for Mtb infection; moreover, during two-months' longitudinal sampling, only 2% (1/50) were serially Mtb bioaerosol negative. These results necessitate a reframing of the prevailing paradigm of Mtb transmission and infection, and may explain the current inability to elucidate Mtb transmission networks in TB-endemic regions.