Background and Objectives:Non-tuberculous mycobacteria (NTM), especially Mycobacterium abscessus, are emerging causes of pulmonary disease and are often misdiagnosed as tuberculosis in high TB burden countries. Conventional culture methods are time-consuming and may reduce viable organism recovery. Rapidly growing mycobacteria (RGM) medium enables direct inoculation of respiratory specimens and improved recovery of rapidly growing NTM. This study evaluated the utility of RGM medium for isolation of M. abscessus from presumptive pulmonary tuberculosis patients and characterized the isolates using molecular and phylogenetic analyses. Materials and Methods:A total of 223 sputum samples collected from presumptive pulmonary tuberculosis patients. Untreated sputum samples were inoculated onto RGM medium with selective antibiotics and incubated at 30°C for 10 days. Suspected colonies were confirmed by Ziehl-Neelsen staining. Identification was performed by PCR and sequencing of hsp65 and rpoB genes. Phylogenetic analysis was done using the Neighbour-Joining method in MEGA12. Mycobacterium abscessus isolates were further analysed using the GenoType NTM-DR assay. Results:Among the 223 sputum samples processed, 7.6% (17/223) demonstrated positive growth on RGM medium. Of the culture-positive isolates, 64.7% (11/17) were identified as Mycobacterium abscessus, while 35.3% (6/17) were identified as other non-tuberculous mycobacterial (NTM) species. All isolates were positive for the rpoB and hsp65 genes. Eleven M. abscessus isolates were further analysed using the GenoType NTM-DR assay, and no resistance-associated mutations were detected in the erm(41), rrl, or rrs genes. Additionally, all isolates were found to be susceptible to macrolides and aminoglycosides. Conclusion:RGM medium demonstrated good utility for recovery of clinically significant rapidly growing mycobacteria, particularly M. abscessus, directly from sputum samples. Molecular and phylogenetic analyses enabled accurate species identification and characterization. The absence of resistance-associated mutations suggests retained susceptibility to key therapeutic agents. These findings support the use of RGM medium for improved detection of pulmonary NTM infections in TB-endemic settings.

BACKGROUND:Mycobacterium abscessus complex (MABC), comprising Mycobacterium abscessus subsp. abscessus (MABa), Mycobacterium abscessus subsp. bolletii (MABb), and Mycobacterium abscessus subsp. massiliense (MABm), is an emerging group of non-tuberculous mycobacteria with clinically significant infections and challenging treatment outcomes due to extensive antimicrobial resistance. Accurate subspecies identification and characterization of resistance- and virulence-associated determinants are essential for effective disease management. This study aimed to determine the prevalence and subspecies distribution of MABC and to characterize resistance-associated mutations and virulence factors, including biofilm formation. METHODS:A total of 1110 NTM-suspected clinical samples were screened during the study period, between January 2024 and October 2025. Samples negative by GeneXpert MTB/RIF were subjected to Mycobacteria Growth Indicator Tube (MGIT) culture, followed by Ziehl-Neelsen staining and MPT64 antigen testing. Acid-fast bacilli-positive, MPT64-negative isolates were identified as NTM and analyzed using GenoType CM and NTM-DR line probe assays (LPA) for species identification and detection of resistance-associated mutations. A polymerase chain reaction (PCR) assay was optimized to differentiate MABa and MABm. All MABC clinical strains were further characterized for colony morphology (smooth and rough) and biofilm formation. Three biofilm-producing MABa strains (2 rough and 1 smooth) that were detected as macrolide-resistant by NTM-DR were subjected to whole-genome sequencing (WGS). RESULTS:Among 1110 clinical samples, MABC was identified in 2.25% (n = 25) of cases, while other NTM species accounted for 4.41% (n = 49). Among 25 MABC clinical strains, 14 (56%) were MABm, and 11 (44%) were MABa, as confirmed by both LPA and PCR. LPA-NTM DR detected erm(41) T28 sequevar (n = 9) and C28 mutation (n = 2) among MABa strains, with one strain exhibiting aminoglycoside resistance-associated rrs mutation. Nineteen isolates displayed a smooth morphotype (MABa = 8 and MABm = 11), and six were rough (MABa = 3 and MABm = 3). Biofilm formation was observed in both smooth (n = 5) and rough (n = 4) morphotypes. WGS analysis confirmed erm(41) T28 sequevar, identified a missense mutation (A238G), and revealed genes associated with glycopeptidolipid biosynthesis. CONCLUSIONS:Our findings provide important insights into subspecies identification and genetic determinants associated with drug resistance and virulence in MABC. The biofilm-forming ability observed in both smooth and rough morphotypes emphasizes its potential role in persistence and treatment challenges, emphasizing the need for comprehensive diagnostic strategies.

BACKGROUND:Undernutrition is the leading population-attributable risk factor for tuberculosis (TB), yet whether associated immune impairments are reversible with nutritional rehabilitation remains unclear. METHODS:In TB LION (Puducherry, India), 105 QuantiFERON-positive household contacts were stratified by BMI (<18.5 vs ≥18.5 kg/m2). Participants with low BMI (n=53) received 6 months of food rations plus daily multiple micronutrient supplement (MMS) without iron. Fourteen cytokines were measured by Luminex in supernatants from the unstimulated (Nil) and M. tuberculosis (Mtb)-antigen-stimulated (TB2) IGRA assay at baseline and 6 months; 11 with acceptable detection rates constituted the primary analytic set. Linear regression tested associations of weight and hemoglobin change with composite immune pathway scores. RESULTS:At baseline, participants with low BMI had attenuated Mtb-specific Th1 cytokine responses (interaction GMR 0.70 for IFN-γ, 0.55 for IL-2; both p=0.005), despite comparable or elevated innate and regulatory cytokines. After 6 months, Th1 responses increased (IFN-γ change GMR 1.41, 95% CI 1.10-1.80, p=0.005, q=0.06; IL-2 1.63, 1.01-2.63, p=0.046, q=0.25, suggestive). This increase reflected falling unstimulated background, not higher stimulated output. Weight gain was unrelated to composite scores but associated with elevated concentrations of 7 of 14 cytokines (all p<0.05). Hemoglobin gain was inversely associated with Th17 and pro-inflammatory scores but not Th1. CONCLUSIONS:Six months of combined food rations and daily MMS was followed by improved antigen-specific Th1 cytokine responses, suggesting this impairment may be partially reversible on a clinically feasible timescale. As a single-arm study without a concurrent comparator with undernutrition measured at follow-up, observed changes cannot be causally attributed to the intervention. Trial registration: NCT03598842.

Background:Tuberculosis (TB) remains the leading cause of death from a single infectious agent. Current diagnostic tools are limited, especially in low-resource settings. The World Health Organization's (WHO) Target Product Profiles (TPPs) call for rapid, non-sputum-based diagnostics with high sensitivity and specificity. This study evaluates our previously published TB-associated host-immune biomarkers alongside small-size signatures from other studies, in our previously published non-human primate (NHP) TB infection study dataset (GSE76703) and two previously published human datasets (GSE144127, GSE42834), which include other disease group comparators, including sarcoidosis. These were also evaluated in a small-scale, exploratory qPCR pilot study to assess the feasibility of implementing these previously validated signatures in a South Indian TB patient cohort, comparing their diagnostic performance against WHO TPP criteria. Methods:Twenty-six genes from published signatures (INDUK, Roe1/Roe3, Sweeney3, RISK6) were analyzed in these NHP and human datasets, using network and machine learning approaches, prior to exploratory evaluation using single and multiplex qPCR assays. These were tested using peripheral blood sample RNAs from pulmonary TB (PTB) (n = 15) and extrapulmonary TB (EPTB) (n = 15) patients and high-incidence controls (n = 15). The diagnostic performance of biomarkers, prior signatures, and novel promising combinations were assessed against WHO TPPs for triage and confirmatory tests. Results:Several biomarker signatures successfully distinguished active TB ((ATB) PTB and EPTB combined) from controls. The minimal INDUK signature (GBP1 + IFIT3) met the optimal TPP criteria for both triage and confirmatory testing for PTB (100% sensitivity and specificity, area under the receiver operating characteristic curve (AUROC:1)) and achieved the 80% sensitivity, 100% specificity threshold for EPTB (AUROC: 0.92 CI: 0.8261-1.00). Combined signatures incorporating genes from INDUK, Roe1, and Sweeney3 further improved diagnostic accuracy for ATB overall (AUROC: 0.98 95% CI: 0.9472-1.00). Conclusion:This preliminary pilot study demonstrates successful evaluation of biomarker signatures as diagnostic qPCR assays for TB diagnosis and, to our knowledge, is the first study to demonstrate the potential for combined host-immune biomarker signatures from different studies that meet WHO TPP benchmarks. These findings support the potential for the development of low-cost, field-adaptable diagnostic tools. Further validation is now under way on a larger cohort of TB patients and controls.

Abstract Background Estimating bacterial load in clinical samples has important applications in tuberculosis (TB) management, including assessment of disease severity, treatment response, and baseline genome copies required for sequencing. However, rapid and affordable tools for quantifying Mycobacterium tuberculosis ( M. tuberculosis ) remain limited. Methods We developed a high-resolution melt (HRM) based quantitative PCR assay using molecular beacon chemistry targeting the single-copy RD9 region of M. tuberculosis . Analytical performance was assessed using 10-fold serial dilutions of H37Rv DNA. Clinical validation included DNA from 100 M. tuberculosis culture isolates and 40 sputum samples from Xpert MTB/RIF- and culture-positive pulmonary TB patients. To evaluate specificity, we tested 30 non-tuberculous mycobacterium (NTM) culture isolates from patients infected with Mycobacterium abscessus (n=25) and Mycobacterium fortuitum (n=5) and DNA from saliva samples of 10 healthy controls. Results The HRM-qPCR assay showed a linear dynamic range from 10 1 to 10 6 genome copies per reaction, with a lower limit of detection of 10 copies. Standardized melt-curve analysis yielded a single target-specific peak at 73.7±0.12°C across dilutions, confirming specific amplification. Sensitivity for M. tuberculosis detection was 100% in culture isolates and 95.0% (38/40) in sputum, with no false positives among M. tuberculosis -negative controls. Assay specificity was 100% in both culture isolates and sputum, with no additional melt peaks. We did not observe any peaks indicative of non-specific binding in NTMs. Amplification was observed in two NTM samples whose Tm matched M. tuberculosis RD9 (median M. tuberculosis copies=678.5), suggesting possible co-infection or contamination. No amplification or specific melt peaks were observed in saliva samples, indicating high probe specificity. Conclusions Molecular beacon-based HRM-qPCR assay enables rapid, highly specific quantification of M. tuberculosis genome copies in clinical samples and has potential utility for treatment monitoring, triaging specimens for sequencing, and assessing transmission risk in high-burden settings.

This study investigated immune cell distributions, cell-specific immune markers, and selected biomarker targets in pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) using multiparametric flow cytometry (MFC). Whole blood was collected from 45 individuals, including healthy controls (HC), EPTB, and PTB patients (n = 15/group). Peripheral blood leukocytes were analysed by MFC to characterize CD4+ and CD8+ T cells, natural killer (NK), invariant NKT (iNKT) and NKT cells, classical (CM), intermediate (IM) and non-classical monocytes (NCM), and activated monocytes (AM). Expression of GBP1, CALCOCO2, IFIT3, SNX10, ARG1, PD-1, and PD-L1 was assessed across these immune subsets. Increased frequencies of NK, NKT, and monocytes were observed in PTB and EPTB compared with HC, while CD4+, CD8+, iNKT, and AM were reduced. Monocyte-to-lymphocyte ratios were incrementally elevated in EPTB and PTB compared with HC. Despite variability of expression within groups, median biomarker fold-change expression changes were found between HC, EPTB and PTB groups; (i) (>2.0FC) for ARG1 in CD4, CD8, CM and AM, for CALCOCO2 in AM, GBP1 in CD8 and NCM, PD-1 in CD4, CD8, NK, IM and AM, PD-L1 in CD4, CD8, iNKT and NKT, NK, IM and AM and SNX10 in CD4, CD8, NCM, IM and AM (ii) (<2.0FC) in TB vs HC for CALCOCO2 in iNKT and NKT, IFIT3 in NCM, PD-1 in NK and NCM, PD-L1 in NCM, IM and AM and SNX10 in AM. Statistical significance was achieved for ARG1 (P = 0.017) in CD4 cells. Our findings highlight distinct immune cell and biomarker signatures in PTB and EPTB.

Background India faces a challenge of dual burden of tuberculosis (TB) and anaemia. The later has a bidirectional relationship with TB and is associated with delayed recovery, poor treatment outcomes, and increased mortality. However, anaemia and its types are often overlooked in routine TB management, and little is known about how its pathophysiology changes during anti-tubercular treatment (ATT). Objective To observe changes in the types of anaemia in a cohort of new pulmonary TB patients in Puducherry post ATT, focussing on ACD. Methods A community based prospective longitudinal cohort study was conducted among sputum smear- positive TB patients (N=176, aged ≥18 years), newly diagnosed and enrolled between 2017-2019 and followed-up until the end of ATT in 2022. 145 participants completed the follow-up. In addition to sociodemographic characteristics haematological and biochemical parameters such as CBC, ferritin, transferrin, serum iron, sTfR, and CRP were measured at the start and end of treatment. Anaemia was classified based on WHO definition and it types were classified using sTfR/Log10 ferritin values. Data were collected using Epicollect and analysed with STATA14. Results Among 176 participants who met the inclusion criteria, majority were aged 31-60 years (71%), and were males (73.3%). At the start of ATT, 63% (111/176) had anaemia, ACD being the predominant [84.6% (94/111)] type, followed by IDA [13.5% (15/111)], other types being ACD+IDA and macrocytic anaemia (0.9% each). Anaemia prevalence declined to 44% (64/145) by the end of ATT; ACD declined by 29.9% (from 84.6% to 54.7%) whereas IDA increased by 22.4% (from 13.5% to 35.9%). Anemia prevalence among women at baseline (82 %) and endline (78 %) were substantially higher. The increase in ferritin levels among women was much lower compared to men. On categorizing the participants based on the types of anaemia at the beginning and of ATT, the levels were suboptimal even after ATT, especially in women with IDA (11 ng/mL in ACD to IDA and 13 ng/mL in IDA groups). Despite a decline in overall CRP levels post ATT, the levels were high (5.7 to 9.8 mg/L) compared to the RIR cut-off of 2 mg/L. Conclusion Anaemia, particularly ACD, is highly prevalent in newly diagnosed TB patients and does not completely resolve with ATT alone, with residual inflammatory risk. Women have iron deficiency in addition to ACD and could be treated with iron supplements at least after the intensive phase of TB treatment.

Background:Detection of extrapulmonary tuberculosis (EPTB) by Ziehl-Neelsen (Z-N) staining in fine needle aspirates is challenging due to the low yield of acid-fast bacteria (AFB). Mycobacterial culture, the gold standard, takes 4-8 weeks. Polymerase chain reaction with 100% sensitivity and 92.1% specificity is expensive. Mycobacterial antigens produced by the tubercle bacilli consist of several proteins and enzymes. The protein purified from Mycobacterium tuberculosis is called MPT. The MPT64, a 24-kd protein, has not been detected in non-tuberculous mycobacteria. We aim to study the role of immunocytochemical (ICC) in the detection of EPTB in fine needle aspiration cytology materials by using MPT64 antibody and compare it with culture and Z-N staining, as ICC is not routinely practiced for diagnosing EPTB. Materials and Methods:A total of 134 patients having enlarged nodes with suspected EPTB were included; however, only 96/134 cases were suitable for statistical analysis. Papanicolaou, May-Grünwald-Giemsa, Z-N staining, ICC, and mycobacteria culture were performed. Results:AFB was positive in 16%, 22.9% of culture-positive, and 11% of MPT64 positive. The sensitivity and specificity of ICC compared to mycobacterial culture were 45.4% and 99%, respectively. ICC and culture had a moderate agreement with the Kappa value of 0.535. The positive and negative predictive values of ICC with culture were 91% and 86%, respectively. Conclusion:This study tried to improve the technique's sensitivity to facilitate its use in routine laboratory practice. Nonetheless, our results showed no significant improvement over the currently popular Z-N stain, although a comparison between the ICC technique performed on smears and cell block sections showed better results in the latter.

Background Tuberculosis (TB) remains a major global health challenge, particularly in developing countries. Non-sputum diagnostic tools are the need of the hour for effective TB diagnosis, especially in paucibacillary and extrapulmonary cases. This study evaluated the diagnostic accuracy of urine lipoarabinomannan (LAM) in presumptive TB patients in South India. Materials and methods The cross-sectional study, with a sample size of 94, was conducted between May 2022 and November 2023 in a tertiary teaching institute. Urine LAM was detected using ELISA, and results were compared with MGIT liquid culture, GeneXpert, and AFB smear. Chest X-ray scores were assessed using the Timika system. Diagnostic accuracy (sensitivity, specificity, PPV, NPV) and associations with disease severity (AFB smear grades, CXR scores) were analyzed. Results Urine LAM showed a sensitivity of 97.7 % and specificity of 38 % compared to MGIT liquid culture. In confirmed TB cases (microbiologically and clinically diagnosed), sensitivity and specificity were 94.5 % and 80 %, respectively. Urine LAM outperformed AFB smear (61.36 % sensitivity) and GeneXpert (88.6 % sensitivity). In extrapulmonary TB, urine LAM demonstrated 100 % sensitivity and NPV. Higher urine LAM levels correlated significantly with higher AFB smear grades (p < 0.05). Conclusion Urine LAM ELISA demonstrated high sensitivity and NPV, making it a valuable screening test for TB, particularly in paucibacillary and extrapulmonary cases. Its association with higher AFB smear grades and chest X-ray scores suggests potential for assessing disease severity and treatment response. Further research using next-generation assays is needed to validate its diagnostic performance and suitability for point-of-care use.

Introduction:An autopsy is a valuable tool for finding the cause of death, exploring the clinical diagnosis, documenting unexpected findings, and resolving diagnostic questions. However, this may subject the forensic pathologist and other workers to a wide variety of blood-borne and aerosolized pathogens. Tuberculosis (TB) is the most common cause of illness and death, resulting in infection transmission in the autopsy room. Our objective in this study was to estimate the prevalence of pulmonary and extrapulmonary tuberculosis among forensic autopsies in a tertiary care hospital in South India. Material and Methods:We identified positive TB cases from acid-fast bacteria staining and culture (Mycobacterium Growth Indicator Tube and Lowenstein-Jensen medium) out of 380 autopsy cases. Results:The prevalence of tuberculosis was 2.4% (n = 9), among which 2.1% of cases were positive for only pulmonary tuberculosis (n = 8), and 0.3% of cases had both pulmonary and extrapulmonary involvement (n = 1). In the bivariate analysis of TB cases, sex, occupation, family history of TB, habit of smoking, BCG vaccine scar, period of hospital stay, and cause of death were potentially significant. Conclusion:The prevalence of TB in forensic autopsy cases were similar to forensic autopsy-based studies, and it was less as compared to the prevalence of TB in the general population.

Stress ulcer prophylaxis is started in the critical care unit to decrease the risk of upper gastrointestinal ulcers in critically ill persons and to decrease mortality caused by stress ulcer complications. Unfortunately, the drugs are often continued after recovery through discharge, paving the way for unnecessary polypharmacy.Study designWe conducted a retrospective cross-sectional study including patients admitted to the adult critical care unit and started on the stress ulcer prophylaxis with a proton pump inhibitor (PPI) or histamine receptor 2 blocker (H2 blocker) with an aim to determine the prevalence of inappropriate continuation at discharge and associated factors.Result3200 people were initiated on stress ulcer prophylaxis, and the medication was continued in 1666 patients upon discharge. Indication for long-term use was not found in 744 of 1666, with a 44% prevalence of inappropriate continuation. A statistically significant association was found with the following risk factors: discharge disposition (home vs other medical facilities, p=0.002), overall length of stay (more than 10 days vs less than or equal to 10 days, p<0.0001), mechanical ventilator use (p<0.001), number of days on a mechanical ventilator (more than 2 days vs less than or equal to 2 days, p<0.001) and class of stress ulcer prophylaxis drug used (H2 blocker vs PPI, p<0.001).ConclusionThe prevalence of inappropriate continuation was found to be higher than prior studies. Given the risk of unnecessary medication intake and the associated healthcare cost, a web-based quality improvement initiative is being considered.

Background:Tuberculosis (TB) disrupts iron balance through systemic inflammation. Pulmonary tuberculosis (PTB) is linked to diverse anaemia types, necessitating intricate haematological and biochemical assessments for diagnosis. This study aims to describe the prevalence of anaemia of chronic disease (ACD), iron deficiency anaemia (IDA) among PTB patients and factors associated with these types of anaemia. Methods:A cross-sectional analysis was conducted from community-based cohort study involving sputum-positive PTB patients from 2018 to 2020 in urban Puducherry. Participants were enrolled from 10 primary health centres within 2 weeks of initiating anti-tubercular treatment (ATT). Blood samples were collected for assessing haematological and biochemical parameters. The sTfR/log ferritin ratio was used to distinguish between ACD and IDA. Data were captured using Epicollect5 and analysed using STATA V14. Result:Of the 176 PTB patients included, 63.07% (111/176) had anaemia, with ACD being the predominant type (84.6%, 94/111). The C-reactive protein (CRP) levels were higher among the anaemic group [40.77 (16.66-58.51) mg/dl vs 24.65 (14.23-47.26) mg/dl] and higher among the ACD as compared to IDA [46.9 (22.3-61.2) vs 20.8 (13.0-39.1) mg/dl]. Undernourished [adjusted prevalence ratio (APR) =3.43; confidence interval (CI): 1.21-9.69] and patients having low risk of dependence on tobacco [APR = 1.52; CI: 1.10-2.11] had higher risk of ACD. Female patients had higher risk of IDA [APR = 4.95, P < 0.01]. Conclusion:The largest proportion of the PTB participants with anaemia had ACD. Acute-phase reactant and inflammatory marker are increased among newly diagnosed new sputum smear-positive (NSP) PTB participants at the start of ATT. Addressing inflammation is needed for combating anaemia in PTB patients.

Tuberculosis remains a global public health challenge, with a substantial number of undiagnosed cases contributing to ongoing transmission and increasing disease burden. A cost-effective triage test for individuals displaying tuberculosis symptoms or at risk of disease could offer an affordable solution. In this regard, non-sputum-based tests that have a minimum of 90% sensitivity and 70% specificity have been prioritised by WHO to rule out tuberculosis and identify the individuals that require further testing.

Background: Mycobacterium (M.) bovis is a member of Mycobacterium tuberculosis complex (MTBC). Clinical infection caused by M. bovis is indistinguishable from other MTBC and could pose a potential challenge for control of TB epidemic due to its zoonotic nature. Availability of reliable molecular diagnostic methods such as Genotype MTBC based on line probe assay (LPA) paves way for reliable differentiation of M. bovis from other MTBC. Objective: To determine the proportion of Mycobacterium bovis among the Mycobacterium tuberculosis complex isolates from patients with tuberculosis. Methods: In our study, we analysed MGIT positive cultures and performed Line probe assay (LPA) for identification of MTBC isolates. Total of 206 patient samples were taken, 104 pulmonary and 102 from extrapulmonary sites. Results: M.tuberculosis/ / M.canettii was isolated in all pulmonary specimens (100%). Among 102 extrapulmonary samples, 99 % was identified as M.tuberculosis/ M.canettii, and 1 % as M. bovis BCG. Conclusion: Our study suggests that zoonotic TB by M. bovis may not be as prevalent in India and hence may not constitute a significant risk to public health in India.

IntroductionMycobacterium tuberculosis has been extensively studied for mutations leading to drug resistance. Pyrazinamide is a drug acting on the semi-dormant bacteria that is responsible for relapse of tuberculosis. This drug helped reduce the treatment duration of tuberculosis from nine to six months. However, this drug is not being screened for resistance along with Rifampicin and Isoniazid.Aims and objectivesThis study aimed to estimate the proportion of pncA gene mutation among tuberculosis patients and its association between treatment outcomes, clinical characteristics, and phenotypic drug resistance.Methodology: A total of 154 samples included 73 drug-resistant and 81 drug-susceptible isolates. The isolates were subjected to DNA extraction and amplification using conventional PCR. The PCR product was sequenced by the Sanger sequencing method, and phenotypic drug susceptibility testing was done using the broth dilution method. The association of this gene with the treatment outcome was done by following up with the patients till the end of the regimen.ResultsNone of the drug susceptible tuberculosis patients showed significant non-synonymous mutations. Among the drug-resistant TB patients, seven unique significant mutations out of 73 isolates (9.6%) were distributed among Isoniazid-resistant tuberculosis and Multi-Drug Resistant Tuberculosis isolates. No association was found between the mutations and the clinical characteristics of the subjects harboring these isolates.ConclusionThis study estimated seven unique mutations in drug-resistant tuberculosis and none in drug-sensitive tuberculosis. Isolates harboring was not significantly associated with the participant's treatment outcome and other clinical characteristics. The pyrazinamide resistance testing by the phenotypic and genotypic methods was found to be in concordance.

Background:Health care workers (HCWs) are at risk of acquiring tuberculosis (TB) infection and disease due to occupational exposure. But there are no national guidelines on routine screening for TB (active case finding (ACF)) among HCWs and understand its implementation and feasibility.Methods:This study was conducted among HCWs in a teaching hospital in India. We used symptom screening to identify those with presumptive TB and were further evaluated for diagnosis of TB.Results:A total of 1,001 HCWs were screened over a period of 18 months. In our study, 51 (5.1%) HCWs were found to have presumptive TB and on further evaluation, 5 (0.5%) of these patients were diagnosed with active TB. The number needed to screen (NNS) for one active TB among the HCWs was 200. Alcohol use was significantly associated with both presumptive TB (P = 0.037) and active TB (P = 0.035) among HCWs, and exposure to active TB patients (P = 0.014) in the family and workplace and increased frequency of exposures (P = <0.001) were associated with presumptive TB.Conclusion:ACF for TB among HCWs had a good yield in our study. ACF utilizing routine national TB program guidelines is feasible to be implemented among HCWs to aid in the early diagnosis and treatment of TB in this high-risk group.

In leprosy, early diagnosis is crucial to prevent transmission and onset of disabilities of the disease. The purpose of this study was to determine usefulness of quantitative real-time polymerase chain reaction (PCR) in clinically diagnosed cases of leprosy. Thirty-two leprosy cases were included. The real-time PCR was performed using commercial kit targeting Mycobacterium leprae-specific insertion sequence element. The slit skin smear was positive in two (22.2%) borderline tuberculoid (BT) patients, five (83.3%) borderline lepromatous (BL) patients, and seven (50%) lepromatous leprosy (LL). The positivity of quantitative real-time PCR in BT, BL, LL, and pure neuritic leprosy were 77.8%, 83.3%, 100%, and 33.3%, respectively. Using histopathology as the gold standard, sensitivity of quantitative real-time PCR was 93.1%, and specificity was 100%. The DNA load was higher in LL (3,854.29/106 cells), followed by BL (140.37/106 cells), and BT (2.69/106 cells). Because of the high sensitivity and specificity of real-time PCR, our study strongly suggests the use of real-time PCR as a diagnostic tool for leprosy.

Background Pulmonary tuberculosis (PTB) is commonly associated with reversible peripheral blood abnormalities. The evolution of tuberculosis (TB)-associated anemia with anti-tuberculosis treatment (ATT) has not been well elucidated. This study aimed to compare the hematological profiles at the start and end of the ATT among new sputum smear-positive (NSP) PTB patients in Puducherry, India. Methods A prospective cohort study was conducted in the 10 urban primary health centers of Puducherry from 2017 to 2020. All the NSP PTB participants aged ≥18 years registered under the National Tuberculosis Elimination Program (NTEP) were contacted within two weeks of the start of the ATT. All eligible participants were enrolled, and they were followed up till the end of ATT (180 days). Hematological profiles and anthropometric measurements were compared at the start and end of the ATT. Binomial logistic regression analysis was used to assess the predictors of changes in the anemia status at the start and end of the ATT. Results Out of 176 NSP PTB participants, 145 were followed up after treatment. Initially, 63% (111/176) patients had anemia, which decreased to 44% (64/145) by the end of treatment. The risk factors for a negative change in hemoglobin levels were female gender, below poverty level, underweight, and reduced iron intake. The adjusted risk ratios (ARRs) were 1.53 (1.24-1.88), 1.18 (1.01-1.38), 1.29 (1.02-1.64), and 1.26 (1.05-1.51),respectively. Conclusion ATT may lead to the resolution of TB-associated anemia. Moreover, female gender, possession of a red ration card, being underweight, and reduced iron intake were identified as risk factors for negative changes in hemoglobin levels during treatment.

BACKGROUND Development of a prediction model using baseline characteristics of tuberculosis (TB) patients at the time of diagnosis will aid us in early identification of the high-risk groups and devise pertinent strategies accordingly. Hence, we did this study to develop a prognostic-scoring model for predicting the death among newly diagnosed drug sensitive pulmonary TB patients in South India. METHODS We undertook a longitudinal analysis of cohort data under the Regional Prospective Observational Research for Tuberculosis India consortium. Multivariable cox regression using the stepwise backward elimination procedure was used to select variables for the model building and the nomogram-scoring system was developed with the final selected model. RESULTS In total, 54 (4.6%) out of the 1181 patients had died during the 1-year follow-up period. The TB mortality rate was 0.20 per 1000 person-days. Eight variables (age, gender, functional limitation, anemia, leukopenia, thrombocytopenia, diabetes, neutrophil-lymphocyte ratio) were selected and a nomogram was built using these variables. The discriminatory power was 0.81 (95% confidence interval: 0.75-0.86) and this model was well-calibrated. Decision curve analysis showed that the model is beneficial at a threshold probability ~15-65%. CONCLUSIONS This scoring system could help the clinicians and policy makers to devise targeted interventions and in turn reduce the TB mortality in India.

PURPOSE:We aimed this study to standardize real time - polymerase chain reaction (RT-PCR) for the detection of Mycobacterium tuberculosis (Mtb) in cerebrospinal fluid (CSF) samples and compare its diagnostic performance with GeneXpert (Xpert), Mycobacteria Growth Indicator Tube (MGIT) and Multiplex PCR (MPCR) for tuberculous meningitis (TBM).METHODOLOGY:A total of 217 CSF samples were obtained from patients with suspected TBM during the study period between January 2019 and December 2021. The optimal cycle threshold (CT) of RT-PCR was determined by comparing different gene targets of Mtb (IS6110, 16SrRNA, HSP65 and Ag85B). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) was determined for RT-PCR, Xpert, MGIT960 and MPCR. Diagnostic accuracy of these assays was compared by using clinical diagnosis as reference standard.RESULTS:IS6110RT-PCR was found to be highly sensitive as compared to other gene targets. Sensitivities of IS6110RT-PCR, MPCR, Xpert and MGIT against a reference standard of definite, probable and possible TBM were 36.7%, 21.1%, 16.7% and 6.7%, respectively; specificities were 97.6%, 100%, 100% and 100%, respectively. Xpert, RT-PCR, MPCR and MGIT960 detected 6.91% (n = 15), 5.99% (n = 13), 5.99% (n = 13) and 2.76% (n = 6) of definite TBM, respectively. RT-PCR detected 6.45% (n = 14) and 2.76% (n = 6) of possible TBM and probable TBM, respectively and MPCR detected 1.38% (n = 3) of possible and probable TBM each.CONCLUSION:IS6110RT-PCR is highly sensitive for primary screening of suspected TB cases, which may help clinicians to start appropriate patient's treatment with clinical suspicion of TBM.