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Background: Pulmonary sarcoidosis (SAR) and tuberculosis (TB) are two granulomatous lung-diseases and often pose a diagnostic challenge to a treating physicians., Objective: The present study aims to explore the diagnostic potential of NMR based serum metabolomics approach to differentiate SAR from TB., Materials and Method: The blood samples were obtained from three study groups: SAR (N = 35), TB (N = 28) and healthy normal subjects (NC, N = 56) and their serum metabolic profiles were measured using 1D 1 H CPMG (Carr-Purcell-Meiboom-Gill) NMR spectra recorded at 800 MHz NMR spectrometer. The quantitative metabolic profiles were compared employing a combination of univariate and multivariate statistical analysis methods and evaluated for their diagnostic potential using receiver operating characteristic (ROC) curve analysis., Results: Compared to SAR, the sera of TB patients were characterized by (a) elevated levels of lactate, acetate, 3-hydroxybutyrate (3HB), glutamate and succinate (b) decreased levels of glucose, citrate, pyruvate, glutamine, and several lipid and membrane metabolites (such as very-low/low density lipoproteins (VLDL/LDL), polyunsaturated fatty acids, etc.)., Conclusion: The metabolic disturbances not only found to be well in concordance with various previous reports, these further demonstrated very high sensitivity and specificity to distinguish SAR from TB patients suggesting serum metabolomics analysis can serve as surrogate method in the diagnosis and clinical management of SAR., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Changes in expression of membrane antigens may accompany the transition of Mycobacterium tuberculosis (Mtb) from 'dormant' to 'active' states. We have determined whether antibody and T cell responses to Mtb membrane (MtM)-associated antigens, especially the latency-induced protein alpha crystallin (Acr), can discriminate between latent tuberculosis infection (LTBI) and active TB (ATB) disease. Study subjects comprised a previously described cohort of healthcare workers (HCWs, n = 43) and smear-positive ATB patients (n = 10). HCWs were further categorized as occupational contacts (OC, n = 30), household contacts of TB (HC, n = 8) and cured TB (CTB, n = 5). Levels (ΔOD) of serum antibody isotypes (IgG, IgA and IgM) were determined by ELISA and blood T cell proliferative responses were determined by flow cytometry using Ki67 protein as marker for DNA synthesis. Antibodies to MtM and Acr were predominantly IgG and their levels in HCWs and ATB did not differ significantly. However, HCWs showed a significantly higher level of anti-MtM IgM and a significantly lower level of anti-Acr IgA antibodies than the ATB patients. Also, a larger proportion of HCWs showed a high (>1) ΔODAcr/ΔODMtM ratio for IgG. HCWs also showed a higher, though not significantly different from ATB, avidity of anti-MtM (IgG) antibodies. A higher proportion of HCWs (35% of OC, 62.5% of HC and 20% of CTB), compared with ATB (10%) showed a positive T cell response to Acr along with significant difference (P <0.05) between HC and ATB. A significant correlation (r = 0.60, P <0.0001) was noted between T cell responses of HCWs towards Acr and MtM (reported earlier by us) and both responses tended to decline with rising exposure to the infection. Even so, positive responses to Acr (38.5%) were significantly lower than to MtM (92%). Neither antibody nor T cell responses to either antigen appeared affected by BCG vaccination or reactivity to tuberculin. Results of the study suggest that the levels of IgM antibodies to MtM, IgA antibodies to Acr and proliferative T cell responses to both the antigens can potentially discriminate between LTBI and active TB disease. They also underscore the necessity of SOPs for antibody assays., Competing Interests: The authors have declared that no competing interests exist.

A 15-year-old boy presented with a sudden onset of breathlessness for 7 days, gradual loss of weight of 17.6 lbs over the last month and progressive hoarseness of voice for 7 months. The contrast-enhanced computed tomography (CECT) scan revealed a heterogeneously enhancing lesion in the anterior mediastinum with multiple discrete lymph nodes in the cervical and mediastinal locations. The GeneXpert MTB/RIF assay performed on the CT-guided biopsy of the mass was negative, but the culture for Mycobacterium tuberculosis was positive at 7 weeks of incubation. There was a suboptimal radiological response after 6 months of treatment. First-line drug susceptibility testing (DST) performed by line probe assay (LPA) on the positive culture detected high-level resistance to isoniazid. The treatment was modified as per DST results to which the patient responded well. [ABSTRACT FROM AUTHOR]

The persistent morbidity and mortality associated with tuberculosis (TB), despite our continued efforts, has been long recognized, and the rise in the incidence of drug-resistant TB adds to the preexisting concern. The bulk of the TB burden is confined to low-income countries, and rigorous efforts are made to detect, notify, and systematically treat TB. Efforts have been infused with renewed vigor and determination by the World Health Organization (WHO) to eliminate tuberculosis in the near future. Different health agencies worldwide are harvesting all possible strategies apart from consolidating ongoing practices, including prevention of the development of active disease by treating latent TB infection (LTBI). The guidelines for the same were already provided by the WHO and were then adapted in the Indian guidelines for the treatment of LTBI in 2021. While the long-term impact of TBI treatment is awaited, in this article, we aim to discuss the implications in the Indian context. [ABSTRACT FROM AUTHOR]

The article discusses the TRUNCATE TB trial, which explores the use of Bedaquiline, a new drug, in the treatment of rifampicin-sensitive tuberculosis (TB). The trial's findings suggest that the addition of Bedaquiline to the treatment regimen may shorten the duration of treatment and improve success rates. However, the article cautions against premature use of Bedaquiline for drug-sensitive TB, as it may promote drug resistance. The lack of effective reserve drugs for extensively resistant cases is also highlighted. The article emphasizes the need for responsible prescribing and reinforcement of infrastructure for early resistance detection. [Extracted from the article]

Tuberculin skin test (TST) is used most widely for the detection of latent tuberculosis infection (LTBI), even though evidences suggest that it could be underreporting the prevalence of LTBI particularly in high disease-burden settings. We have explored whether in vivo (TST) and in vitro (cell-proliferative) T cell responses to PPD can serve as complementary measures. In addition, we also probed whether in vitro T cell response to cell-membrane antigens (Mem) of Mycobacterium tuberculosis (MTB) can serve as a biomarker for LTBI. Study subjects comprised 43 healthcare workers (HCWs), and 9 smear-positive TB patients served as ‘disease control’. To measure proliferative T cell responses, 0.1 ml blood (diluted 1:10) was incubated (5 days) with test or control antigen. Cells were stained with fluorescent antibodies to T cell (CD3+/CD4+/CD8+) surface markers and, after fixation and permeabilization, to nuclear proliferation marker Ki67. Data was acquired on a flow cytometer. HCWs who had an intimate exposure to MTB showed significantly higher TST positivity (85%) than the rest (43%), notwithstanding their BCG vaccination status. The proliferative responses of CD4+ and CD8+ subsets of T cells were comparable. Sixty seven and 100% TST-negative HCWs, respectively, were positive for proliferative T cell response to PPD and MTBMem. Cumulative positivity (TST or in vitro) was 86% with PPD and 100% with MTBMem indicating complementarity of the two responses. As standalone in vitro assay, MTBMem provided a significantly higher positivity (95%) than PPD (67%). T cell responses of TB patients were ‘generally’ depressed, having implications for the development of immunological assays for ‘progressive’ LTBI. Altogether, these results demonstrate that in vivo and in vitro T cell responses to PPD are complementary and in vitro response to MTBMem can be developed as a highly sensitive biomarker for LTBI. [ABSTRACT FROM AUTHOR]

A case of bronchial artery aneurysm due to pulmonary tuberculosis is reported. The patient presented with massive hemoptysis and the diagnosis was made using multidetector computed tomographic (MDCT) angiography. Selective bronchial arteriogram confirmed the MDCT findings and bronchial artery embolization was successfully performed with cessation of hemoptysis. Our article emphasizes the value of MDCT angiography in the diagnosis and management of such cases. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article related to the imaging of tuberculosis related to abdominal viscera.