The sound of silent RNA in tuberculosis and the lncRNA role on infection.

Tuberculosis (TB) is one of the leading causes of death worldwide, and Diabetes Mellitus is one of the major comorbidities (TB/DM) associated with the disease. A total of 103 differentially expressed ncRNAs have been identified in the TB and TB/DM comparisons. A machine learning algorithm was employed to identify the most informative lncRNAs: ADM-DT, LINC02009, LINC02471, SOX2-OT, and GK-AS1. These lncRNAs presented substantial accuracy in classifying TB from HC (AUCs >0.85) and TB/DM from HC (AUCs >0.90) in the other three countries. Genes with significant correlations with the five lncRNAs enriched common pathways in Brazil and India for both TB and TB/DM. This suggests that lncRNAs play an important role in the regulation of genes related to the TB immune response.

Clinically relevant antibiotic resistance genes are linked to a limited set of taxa within gut microbiome worldwide.

The acquisition of antimicrobial resistance (AR) genes has rendered important pathogens nearly or fully unresponsive to antibiotics. It has been suggested that pathogens acquire AR traits from the gut microbiota, which collectively serve as a global reservoir for AR genes conferring resistance to all classes of antibiotics. However, only a subset of AR genes confers resistance to clinically relevant antibiotics, and, although these AR gene profiles are well-characterized for common pathogens, less is known about their taxonomic associations and transfer potential within diverse members of the gut microbiota. We examined a collection of 14,850 human metagenomes and 1666 environmental metagenomes from 33 countries, in addition to nearly 600,000 isolate genomes, to gain insight into the global prevalence and taxonomic range of clinically relevant AR genes. We find that several of the most concerning AR genes, such as those encoding the cephalosporinase CTX-M and carbapenemases KPC, IMP, NDM, and VIM, remain taxonomically restricted to Proteobacteria. Even cfiA, the most common carbapenemase gene within the human gut microbiome, remains tightly restricted to Bacteroides, despite being found on a mobilizable plasmid. We confirmed these findings in gut microbiome samples from India, Honduras, Pakistan, and Vietnam, using a high-sensitivity single-cell fusion PCR approach. Focusing on a set of genes encoding carbapenemases and cephalosporinases, thus far restricted to Bacteroides species, we find that few mutations are required for efficacy in a different phylum, raising the question of why these genes have not spread more widely. Overall, these data suggest that globally prevalent, clinically relevant AR genes have not yet established themselves across diverse commensal gut microbiota.

Timing of maternal isoniazid preventive therapy on tuberculosis infection among infants exposed to HIV in low-income and middle-income settings: a secondary analysis of the TB APPRISE trial.

BACKGROUND: Infants born to women with HIV in settings with a high tuberculosis burden are at risk of tuberculosis infection and rapid progression to active disease. Maternal isoniazid preventive therapy might mitigate this risk, but optimal timing of therapy remains unclear. The TB APPRISE trial showed that initiation of isoniazid during pregnancy resulted in more frequent adverse pregnancy outcomes than when initiated postpartum. We aimed to determine the proportion of infants testing positive for tuberculosis infection born to mothers who initiated isoniazid therapy antepartum compared with postpartum using two commonly used tests, the test agreement, and predictors of test positivity. METHODS: TB APPRISE was a randomised, double-blind, placebo-controlled, non-inferiority trial done at 13 study sites across eight countries (Botswana, Haiti, India, South Africa, Tanzania, Thailand, Uganda, and Zimbabwe). Pregnant women with HIV on antiretroviral therapy were randomly assigned to receive immediate isoniazid preventive therapy (28 weeks isoniazid [300 mg daily], then placebo until week 40 after delivery) or deferred treatment (placebo until week 12 after delivery, then isoniazid [300 mg daily] for 28 weeks). Mother-infant pairs were followed up until 48 weeks after delivery. We included all liveborn infants with a tuberculin skin test or interferon-γ release assay (IGRA) at 44 weeks. The outcomes assessed in this secondary analysis were tuberculosis test positivity by study group, test agreement, and predictors of test positivity. This study was registered with ClinicalTrials.gov, NCT01494038. FINDINGS: Between Aug 19, 2014, and April 4, 2016, 956 mothers were randomly assigned, and 749 mother-child pairs were included in this secondary analysis. Of 749 infants, 694 (93%) received Bacille Calmette-Guérin (BCG) vaccination, 675 (90%) were born to mothers who had completed isoniazid treatment, 20 (3%) were exposed to tuberculosis, seven (1%) became HIV positive, and one (<1%) developed probable tuberculosis. 43 (6%; 95% CI 4-8]) of 732 infants had a positive IGRA test result and 55 (8%; 6-10) of 727 infants had a positive tuberculin skin test result. Test positivity did not differ by study group (p=0·88 for IGRA; p=0·44 for tuberculin skin test). Test agreement was poor (κ=0·107 [95% CI 0·002-0·212]). Infant tuberculin skin test positivity was associated with breastfeeding (adjusted odds ratio 6·63 [95% CI 1·57-27·9]), BCG vaccination (4·97 [1·50-16·43]), and maternal tuberculin skin test positivity at delivery (3·28 [1·70-6·33]); IGRA positivity was associated with female sex (2·09 [1·06-4·14]). INTERPRETATION: Deferral of maternal isoniazid preventive therapy to early postpartum had no effect on infant tuberculosis acquisition in our trial population, regardless of the diagnostic test used; however, tuberculosis test agreement is poor during infancy. FUNDING: US National Institutes of Health.

Comparative immune responses to Mycobacterium tuberculosis in people with latent infection or sterilizing protection.

There is great need for vaccines against tuberculosis (TB) more efficacious than the licensed BCG. Our goal was to identify new vaccine benchmarks by identifying immune responses that distinguish individuals able to eradicate the infection (TB-resisters) from individuals with latent infection (LTBI-participants). TB-resisters had higher frequencies of circulating CD8+ glucose monomycolate (GMM)+ Granzyme-B+ T cells than LTBI-participants and higher proportions of polyfunctional conventional and nonconventional T cells expressing Granzyme-B and/or PD-1 after ex vivo M. tuberculosis stimulation of blood mononuclear cells. LTBI-participants had higher expression of activation markers and cytokines, including IL10, and IFNγ. An exploratory analysis of BCG-recipients with minimal exposure to TB showed absence of CD8+GMM+Granzyme-B+ T cells, lower or equal proportions of Granzyme-B+PD-1+ polyfunctional T cells than TB-resisters and higher or equal than LTBI-participants. In conclusion, high Granzyme-B+PD-1+ T cell responses to M. tuberculosis and, possibly, of CD8+GMM+Granzyme-B+ T cells may be desirable for new TB vaccines.

Maternal Colonization Versus Nosocomial Transmission as the Source of Drug-Resistant Bloodstream Infection in an Indian Neonatal Intensive Care Unit: A Prospective Cohort Study.

BACKGROUND: Drug-resistant gram-negative (GN) pathogens are a common cause of neonatal sepsis in low- and middle-income countries. Identifying GN transmission patterns is vital to inform preventive efforts. METHODS: We conducted a prospective cohort study, 12 October 2018 to 31 October 2019 to describe the association of maternal and environmental GN colonization with bloodstream infection (BSI) among neonates admitted to a neonatal intensive care unit (NICU) in Western India. We assessed rectal and vaginal colonization in pregnant women presenting for delivery and colonization in neonates and the environment using culture-based methods. We also collected data on BSI for all NICU patients, including neonates born to unenrolled mothers. Organism identification, antibiotic susceptibility testing, and next-generation sequencing (NGS) were performed to compare BSI and related colonization isolates. RESULTS: Among 952 enrolled women who delivered, 257 neonates required NICU admission, and 24 (9.3%) developed BSI. Among mothers of neonates with GN BSI (n = 21), 10 (47.7%) had rectal, 5 (23.8%) had vaginal, and 10 (47.7%) had no colonization with resistant GN organisms. No maternal isolates matched the species and resistance pattern of associated neonatal BSI isolates. Thirty GN BSI were observed among neonates born to unenrolled mothers. Among 37 of 51 BSI with available NGS data, 21 (57%) showed a single nucleotide polymorphism distance of ≤5 to another BSI isolate. CONCLUSIONS: Prospective assessment of maternal GN colonization did not demonstrate linkage to neonatal BSI. Organism-relatedness among neonates with BSI suggests nosocomial spread, highlighting the importance of NICU infection prevention and control practices to reduce GN BSI.

Association of Pregnancy and HIV Status With Molecular-Bacterial Vaginosis in Indian Women.

BACKGROUND: Bacterial vaginosis (BV) is a highly prevalent disorder of the cervicovaginal microbiota. Molecular-BV may put women at increased risk for adverse reproductive and obstetric outcomes. We investigated the association of HIV and pregnancy on the vaginal microbiota and associations with molecular-BV in women of reproductive age from Pune, India. SETTING: We studied vaginal samples from N = 170 women, including N = 44 nonpregnant HIV seronegative, N = 56 pregnant seronegative, N = 47 nonpregnant women with HIV (WWH), and N = 23 pregnant WWH, and collected data on clinical, behavioral, and demographic factors. METHODS: We used 16S rRNA gene amplicon sequencing to characterize the composition of the vaginal microbiota. We classified the vaginal microbiota of these women into community state types based on bacterial composition and relative abundance and further categorized them into molecular-BV versus Lactobacillus -dominated states. To determine associations between pregnancy and HIV status with outcome of molecular-BV, logistic regression models were used. RESULTS: There was a high prevalence of molecular-BV (30%) in this cohort. We found that pregnancy was associated with decreased odds of molecular-BV (adjusted OR = 0.35, 95% CI: 0.14 to 0.87), while HIV was associated with increased odds of molecular-BV (adjusted OR = 2.76, 95% CI: 1.33 to 5.73), even when controlling for multiple relevant factors such as age, number of sexual partners, condom use, and douching. CONCLUSION: Larger and longitudinal studies are needed to further characterize molecular-BV and the vaginal microbiota in pregnant women and WWH and relate these factors to infectious, reproductive, and obstetric outcomes. In the long term, these studies may lead to novel microbiota-based therapeutics to improve women's reproductive and obstetric health.

Challenges with the use of Xpert HPV as a screening tool for oral HPV among people living with HIV (PLHIV): experiences from Pune, India.

BACKGROUND: People living with HIV (PLHIV) are at higher risk for human papillomavirus (HPV)-related oropharyngeal cancers compared to the general population. Xpert HPV test is a polymerase chain reaction (PCR) assay capable of rapid HPV detection. Performing the assay requires minimal intervention by laboratory personnel. Its use could improve oropharyngeal cancer screening among PLHIV living in low-and middle-income countries (LMICs) with limited diagnostic capacities. However, Xpert HPV performance for oral samples has not been evaluated. Here, we describe our experience with Xpert HPV and compare its results with traditional PCR, for oral samples. METHODS: Oral samples from 429 PLHIV receiving care at a tertiary care hospital affiliated antiretroviral therapy center in Pune, India were used. Samples were collected either after a 30s oral rinse and gargle (n = 335) or in combination with cytobrush scraping of the oral mucosa (n = 91). Unsuccessful tests were those that generated an invalid or error result on Xpert HPV. Successful tests were those that generated a positive or negative result. Kappa statistic was used to compare concordance between Xpert HPV and traditional real-time PCR results. RESULTS: There were 29.8% (n = 127) unsuccessful tests, of which 78.7% (n = 100) were invalid and 21.3% (n = 27) were error results. Adding cytobrush scraping to oral rinse as a collection procedure did not significantly reduce the proportion of unsuccessful tests (p = 0.9). For successful tests, HPV positivity on Xpert was 0.3% (n = 1/299). Kappa statistic was 0.11, indicating poor agreement between Xpert HPV and traditional PCR results. CONCLUSIONS: Presently, Xpert HPV appears to have limited use for oral HPV detection among PLHIV using oral samples. More research to improve the diagnostic capabilities of Xpert HPV for oral samples among PLHIV is needed.

QuantiFERON Supernatant-Based Host Biomarkers Predicting Progression to Active Tuberculosis Disease Among Household Contacts of Tuberculosis Patients.

BACKGROUND: The positive predictive value of tuberculin skin test and current generation interferon gamma release assays are very low leading to high numbers needed to treat. Therefore, it is critical to identify new biomarkers with high predictive accuracy to identify individuals bearing high risk of progression to active tuberculosis (TB). METHODS: We used stored QuantiFERON supernatants from 14 household contacts of index TB patients who developed incident active TB during a 2-year follow-up and 20 age and sex-matched non-progressors. The supernatants were tested for an expanded panel of 45 cytokines, chemokines, and growth factors using the Luminex Multiplex Array kit. RESULTS: We found significant differences in the levels of TB-antigen induced production of several analytes between progressors and non-progressors. Dominance analysis identified 15 key predictive biomarkers based on relative percentage importance. Principal component analysis revealed that these biomarkers could robustly distinguish between the 2 groups. Receiver operating characteristic analysis identified interferon-γ inducible protein (IP)-10, chemokine ligand (CCL)19, interferon (IFN)-γ, interleukin (IL)-1ra, CCL3, and granulocyte-macrophage colony-stimulating factor (GM-CSF) as the most promising predictive markers, with area under the curve (AUC) ≥90. IP-10/CCL19 ratio exhibited maximum sensitivity and specificity (100%) for predicting progression. Through Classification and Regression Tree analysis, a cutoff of 0.24 for IP-10/CCL19 ratio was found to be ideal for predicting short-term risk of progression to TB disease with a positive predictive value of 100 (95% confidence interval [CI] 85.8-100). CONCLUSIONS: The biomarkers identified in this study will pave way for the development of a more accurate test that can identify individuals at high risk for immediate progression to TB disease for targeted intervention.

Smokeless tobacco use and oral potentially malignant disorders among people living with HIV (PLHIV) in Pune, India: Implications for oral cancer screening in PLHIV.

INTRODUCTION: In India, smokeless tobacco (SLT) is a predominant form of tobacco used among people living with HIV (PLHIV). Despite SLT being a risk factor for oral potentially malignant disorders (OPMDs), no prior studies have quantified the association of OPMDs with SLT use among PLHIV. This limits the planning of preventive and control strategies for oral cancer among PLHIV, who are at higher risk for the disease. METHODS: We enrolled 601 PLHIV and 633 HIV-uninfected individuals in an oral cancer screening study at BJ Government Medical College, Pune, India. Oral cavity images were collected using an m-Health application and reviewed by three clinicians. Participants with two clinician positive diagnoses were deemed to have suspected OPMDs. Prevalence ratios (PRs) were used to quantify the association between suspected OPMDs and SLT use among PLHIV. PRs for current SLT users, across HIV status and use duration were also estimated. Corrected PRs were obtained by modifying the maximum likelihood estimation. Models were adjusted for age, smoking, alcohol use and CD4 counts. RESULTS: Of those enrolled, 61% were men, median age was 36 years (IQR: 28-44), and 33% currently use SLT. Proportion of current SLT users was similar across PLHIV and HIV-uninfected groups but use duration for current SLT use was higher among PLHIV(p<0.05). Among PLHIV, current SLT users had a 5-times (95% CI:3.1-7.0) higher prevalence of suspected OPMDs, compared to non-users. Relative to HIV uninfected individuals with the same SLT use duration, significant associations with suspected OPMDs were seen for PLHIV with<10 use years (PR: 3.5, 95% CI: 1.5-8.1) but not for PLHIV with≥10 use years (PR: 1.3, 95% CI: 0.9-1.8). CONCLUSION: PLHIV that are current SLT users are at high risk of OPMDs and potentially oral cancer. The development of strategies for screening, early detection, and management of OPMDs must be considered for this group.

Clinical and Immunological Markers of Pulmonary Impairment Among People With HIV in India.

Background: Despite antiretroviral therapy, chronic lung diseases remain an important source of morbidity and mortality in people with HIV (PWH). We sought to identify clinical and immunological markers of pulmonary impairment among PWH in India. Methods: Two hundred ten adult PWH receiving antiretroviral therapy (ART) were prospectively evaluated for 3 years. Plasma concentrations of interleukin (IL)-6, IL-10, tumor necrosis factor alpha, D-dimer, C-reactive protein, soluble (s)CD14, and sCD163 were measured at enrollment. We used multivariable linear and logistic regression to measure the association of baseline and time-varying clinical and immunological variables with spirometry-defined chronic obstructive pulmonary disease (COPD), restrictive spirometry pattern (RSP), preserved ratio impaired spirometry (PRISm), forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC) during the third year of follow-up. Results: After adjusting confounders, females were 7 times more likely to have RSP (95% CI, 2.81 to 17.62; P < .001) and 22 times more likely to have PRISm (95% CI, 7.42 to 69.92; P < .001) compared with men. Higher IL-6 concentrations were associated with lower FEV1 z-scores (ß, -0.14 per log-higher; 95% CI, -0.29 to 0.008; P = .06) and higher odds of COPD (adjusted odds ratio [aOR], 2.66 per log-higher; 95% CI, 1.16 to 6.09; P = .02). Higher D-dimer concentrations were associated with lower FVC z-scores (ß, -0.40 per log-higher; 95% CI, -0.78 to -0.01; P = .04). Conversely, higher IL-10 concentrations were associated with lower odds of PRISm (aOR, 0.76 per log-higher; 95% CI, 0.59 to 0.99; P = .04). Conclusions: Female sex, higher concentrations of IL-6 and D-dimer, and lower concentrations of IL-10 were associated with pulmonary impairment in adult PWH receiving ART in India.

Inflammatory profile associated with insulin resistance in non-overweight versus overweight people living with HIV in Pune, Western India.

BACKGROUND: People living with HIV have greater diabetes (T2DM) than the general population despite lower prevalence of overweight/obesity. Both insulin resistance (IR), a T2DM precursor, and HIV are independently associated with chronic inflammation. Inflammation may be a pathophysiological link explaining IR in people living with HIV who are not overweight but is not well understood. AIMS: To study the association between inflammation and IR in non-overweight and overweight people living with HIV. METHODS: In a cohort of adult people living with HIV with undetectable viral load in Pune, India, we measured fasting insulin, glucose, and 9 inflammatory markers. IR was defined as HOMA-IR ≥2, and non-overweight as BMI ≤23 kg/m2. We used modified Poisson regression to evaluate the association between inflammatory markers and IR in overweight and non-overweight. RESULTS: Of 288 participants, 66% (n = 189) were non-overweight. Among non-overweight, prevalence of IR was 34% (n = 65). Each doubling of MCP-1 and leptin was associated with IR on univariate analysis (prevalence ratio (PR) 1.29, 95%CI 1.07-1.53, p < 0.01; PR 1.13 95%CI 1.01-1.26, p = 0.03). Leptin remained associated with IR after adjustment for age, MCP-1, gender, cholesterol, and waist circumference (adjusted PR 1.20 95%CI 1.06-1.36, p < 0.01). Among overweight, prevalence of IR was 69% and no markers were associated with IR. CONCLUSIONS: One in 3 non-overweight people living with HIV in India with controlled viremia have IR. Leptin was associated with IR among non-overweight people living with HIV and may provide insight into the pathophysiology of metabolic disease in this population.

Transcriptional Analysis for Tuberculosis in Pregnant Women From the PRegnancy Associated Changes In Tuberculosis Immunology (PRACHITi) Study.

A new tuberculosis (TB) diagnostic cartridge assay, which detects a 3-gene TB signature in whole blood, was not diagnostic in women with maternal TB disease in India (area under the curve [AUC] = 0.72). In a cohort of pregnant women, we identified a novel gene set for TB diagnosis (AUC = 0.97) and one for TB progression (AUC = 0.96).

Host lipidome and tuberculosis treatment failure.

INTRODUCTION: Host lipids play important roles in tuberculosis (TB) pathogenesis. Whether host lipids at TB treatment initiation (baseline) affect subsequent treatment outcomes has not been well characterised. We used unbiased lipidomics to study the prospective association of host lipids with TB treatment failure. METHODS: A case-control study (n=192), nested within a prospective cohort study, was used to investigate the association of baseline plasma lipids with TB treatment failure among adults with pulmonary TB. Cases (n=46) were defined as TB treatment failure, while controls (n=146) were those without failure. Complex lipids and inflammatory lipid mediators were measured using liquid chromatography mass spectrometry techniques. Adjusted least-square regression was used to assess differences in groups. In addition, machine learning identified lipids with highest area under the curve (AUC) to classify cases and controls. RESULTS: Baseline levels of 32 lipids differed between controls and those with treatment failure after false discovery rate adjustment. Treatment failure was associated with lower baseline levels of cholesteryl esters and oxylipin, and higher baseline levels of ceramides and triglycerides compared to controls. Two cholesteryl ester lipids combined in a unique classifier model provided an AUC of 0.79 (95% CI 0.65-0.93) in the test dataset for prediction of TB treatment failure. CONCLUSIONS: We identified lipids, some with known roles in TB pathogenesis, associated with TB treatment failure. In addition, a lipid signature with prognostic accuracy for TB treatment failure was identified. These lipids could be potential targets for risk-stratification, adjunct therapy and treatment monitoring.

Baseline IL-6 is a biomarker for unfavourable tuberculosis treatment outcomes: a multisite discovery and validation study.

BACKGROUND: Biomarkers of unfavourable tuberculosis (TB) treatment outcomes are needed to accelerate new drug and regimen development. Whether plasma cytokine levels can predict unfavourable TB treatment outcomes is unclear. METHODS: We identified and internally validated the association between 20 a priori selected plasma inflammatory markers and unfavourable treatment outcomes of failure, recurrence and all-cause mortality among adults with drug-sensitive pulmonary TB in India. We externally validated these findings in two independent cohorts of predominantly diabetic and HIV co-infected TB patients in India and South Africa, respectively. RESULTS: Pre-treatment interferon-γ, interleukin (IL)-13 and IL-6 were associated with treatment failure in the discovery analysis. Internal validation confirmed higher pre-treatment IL-6 concentrations among failure cases compared with controls. External validation among predominantly diabetic TB patients found an association between pre-treatment IL-6 concentrations and subsequent recurrence and death. Similarly, external validation among predominantly HIV co-infected TB patients found an association between pre-treatment IL-6 concentrations and subsequent treatment failure and death. In a pooled analysis of 363 TB cases from the Indian and South African validation cohorts, high pre-treatment IL-6 concentrations were associated with higher risk of failure (adjusted OR (aOR) 2.16, 95% CI 1.08-4.33; p=0.02), recurrence (aOR 5.36, 95% CI 2.48-11.57; p<0.001) and death (aOR 4.62, 95% CI 1.95-10.95; p<0.001). Adding baseline IL-6 to a risk prediction model comprised of low body mass index, high smear grade and cavitation improved model performance by 15% (C-statistic 0.66 versus 0.76; p=0.02). CONCLUSIONS: Pre-treatment IL-6 is a biomarker for unfavourable TB treatment outcomes. Future studies should identify optimal IL-6 concentrations for point-of-care risk prediction.

Association of Maternal Inflammation During Pregnancy With Birth Outcomes and Infant Growth Among Women With or Without HIV in India.

Importance: The association of elevated levels of specific inflammatory markers during pregnancy with adverse birth outcomes and infant growth could indicate pathways for potential interventions. Objective: To evaluate whether higher levels of certain inflammatory markers during pregnancy are associated with preterm birth (PTB), low birth weight (LBW), and infant growth deficits. Design, Setting, and Participants: In this cohort study of pregnant women with or without HIV, 218 mother-infant pairs were followed up from pregnancy through 12 months post partum from June 27, 2016, to December 9, 2019. Pregnant women aged 18 to 40 years and between 13 and 34 weeks of gestation who were receiving antenatal care were enrolled in a cohort stratified by HIV status; sampling was based on convenience sampling from women receiving antenatal care at Byramjee Jeejeebhoy Government Medical College. Exposures: Levels of multiple circulating inflammation markers during the third trimester of pregnancy. Main Outcomes and Measures: The primary study outcome was PTB (<37 weeks' gestation). Secondary outcomes were LBW (<2500 g) and repeated measures (delivery; 6 weeks post partum; and 3, 6, and 12 months post partum using multivariable generalized linear models) of infant growth outcomes (length-for-age, weight-for-age, and weight-for-length z scores). Results: The median age of the 218 women at enrollment was 23 years (IQR, 21-27 years). In multivariable models, higher pregnancy levels of interleukin 17A were associated with increased odds of both PTB (adjusted odds ratio [aOR], 2.62; 95% CI, 1.11-6.17) and LBW (aOR, 1.81; 95% CI, 1.04-3.15). Higher levels of interleukin 1ß were associated with increased PTB (aOR, 1.47; 95% CI, 1.15-1.89) and infant growth deficits (lower length-for-age z score: adjusted ß = -0.10; 95% CI, -0.18 to -0.01; lower weight-for-age z score: adjusted ß = -0.07; 95% CI, -0.14 to 0.001). Conclusions and Relevance: This study suggests that increased levels of certain systemic inflammatory markers, including interleukin 1ß and interleukin 17A, during pregnancy were associated with adverse birth outcomes and infant growth deficits. Future studies should evaluate whether potential interventions to modulate specific inflammatory pathways during pregnancy could improve birth outcomes and infant growth.

Stages of pregnancy and HIV affect diagnosis of tuberculosis infection and Mycobacterium tuberculosis (MTB)-induced immune response: Findings from PRACHITi, a cohort study in Pune, India.

BACKGROUND: Accurate tuberculosis infection (TBI) tests are critical for pregnant women, especially those with HIV, who have a high risk of TB disease. METHODS: We enrolled interferon gamma release assay (IGRA)+ pregnant women with and without HIV in a longitudinal study, followed up at delivery and 6 months postpartum. Tuberculin skin test (TST) and IGRA were compared by HIV status at each timepoint. RESULTS: Of 165 enrolled IGRA+ pregnant women: 35 (21%) had HIV and were on antiretroviral therapy with median CD4 of 476 (IQR 399-586). Compared to antepartum, significantly fewer women remained IGRA+ at delivery [HIV+ n=21/35 (62%, p=0.009); HIV- n=100/130 (77%, p=0.002)] and postpartum [HIV+ n=30/35 (87%, p=0.03); HIV- n=116/130 (89%, p=0.01)]. IGRA/TST discordance was high in pregnant women (HIV+: 51%; HIV-: 25%). Median IFN-γ was lowest for all women at delivery; significantly lower in women with HIV at all timepoints compared to women without HIV. TB incidence was 50/ 1000 person-years and 18/1000 person-years among women with and without HIV respectively. CONCLUSIONS: Pregnancy affects TBI test results and reduces IFN-γ response to M. tuberculosis stimulation. Despite adequate CD4 counts, women with HIV express less IFN-γ than women without HIV, which may explain the high TB incidence in postpartum women with HIV.

Impact of HIV status on systemic inflammation during pregnancy.

OBJECTIVE: There are limited studies on the association of HIV infection with systemic inflammation during pregnancy. DESIGN: A cohort study (N = 220) of pregnant women with HIV (N = 70) (all on antiretroviral therapy) and without HIV (N = 150) were enrolled from an antenatal clinic in Pune, India. METHODS: The following systemic inflammatory markers were measured in plasma samples using immunoassays: soluble CD163 (sCD163), soluble CD14 (sCD14), intestinal fatty acid-binding protein (I-FABP), C-reactive protein (CRP), alpha 1-acid glycoprotein (AGP), interferon-ß (IFNß), interferon-γ (IFNγ), interleukin (IL)-1ß, IL-6, IL-13, IL-17A, and tumor necrosis factor α (TNFα). Generalized estimating equation (GEE) and linear regression models were used to assess the association of HIV status with each inflammatory marker during pregnancy and by trimester, respectively. RESULTS: Pregnant women with HIV had higher levels of markers for gut barrier dysfunction (I-FABP), monocyte activation (sCD14) and markers of systemic inflammation (IL-6 and TNFα), but surprisingly lower levels of AGP, an acute phase protein, compared with pregnant women without HIV, with some trimester-specific differences. CONCLUSION: Our data show that women with HIV had higher levels of markers of gut barrier dysfunction, monocyte activation and systemic inflammation. These markers, some of which are associated with preterm birth, might help explain the increase in adverse birth outcomes in women with HIV and could suggest targets for potential interventions.

Diabetes Mellitus and Tuberculosis Treatment Outcomes in Pune, India.

BACKGROUND: Diabetes mellitus (DM) increases the risk of tuberculosis (TB) disease. Knowledge of the impact of DM on TB treatment outcomes is primarily based on retrospective studies. METHODS: We conducted a prospective cohort study of new pulmonary TB patients with and without DM (TB-DM and TB only) in India. The association of DM with a composite unfavorable TB treatment outcome (failure, recurrence, mortality) over 18 months was determined, and the effect of DM on all-cause mortality and early mortality (death during TB treatment) was assessed. RESULTS: Of 799 participants, 574 (72%) had TB only and 225 (28%) had TB-DM. The proportion of patients with DM who experienced the composite outcome was 20%, as compared with 21% for TB-only participants (adjusted hazard ratio [aHR], 1.13; 95% CI, 0.75-1.70). Mortality was higher in participants with DM (10% vs 7%), and early mortality was substantially higher among patients with DM (aHR, 4.36; 95% CI, 1.62-11.76). CONCLUSIONS: DM was associated with early mortality in this prospective cohort study, but overall unfavorable outcomes were similar to participants without DM. Interventions to reduce mortality during TB treatment among people with TB-DM are needed.

A Two-Gene Signature for Tuberculosis Diagnosis in Persons With Advanced HIV.

Background: Transcriptomic signatures for tuberculosis (TB) have been proposed and represent a promising diagnostic tool. Data remain limited in persons with advanced HIV. Methods: We enrolled 30 patients with advanced HIV (CD4 <100 cells/mm3) in India; 16 with active TB and 14 without. Whole-blood RNA sequencing was performed; these data were merged with a publicly available dataset from Uganda (n = 33; 18 with TB and 15 without). Transcriptomic profiling and machine learning algorithms identified an optimal gene signature for TB classification. Receiver operating characteristic analysis was used to assess performance. Results: Among 565 differentially expressed genes identified for TB, 40 were shared across India and Uganda cohorts. Common upregulated pathways reflect Toll-like receptor cascades and neutrophil degranulation. The machine-learning decision-tree algorithm selected gene expression values from RAB20 and INSL3 as most informative for TB classification. The signature accurately classified TB in discovery cohorts (India AUC 0.95 and Uganda AUC 1.0; p < 0.001); accuracy was fair in external validation cohorts. Conclusions: Expression values of RAB20 and INSL3 genes in peripheral blood compose a biosignature that accurately classified TB status among patients with advanced HIV in two geographically distinct cohorts. The functional analysis suggests pathways previously reported in TB pathogenesis.

The Kynurenine/Tryptophan Ratio Is a Sensitive Biomarker for the Diagnosis of Pediatric Tuberculosis Among Indian Children.

Objectives: Pediatric tuberculosis (TB) remains difficult to diagnose. The plasma kynurenine to tryptophan ratio (K/T ratio) is a potential biomarker for TB diagnosis and treatment response but has not been assessed in children. Methods: We performed a targeted diagnostic accuracy analysis of four biomarkers: kynurenine abundance, tryptophan abundance, the K/T ratio, and IDO-1 gene expression. Data were obtained from transcriptome and metabolome profiling of children with confirmed tuberculosis and age- and sex-matched uninfected household contacts of pulmonary tuberculosis patients. Each biomarker was assessed as a baseline diagnostic and in response to successful TB treatment. Results: Despite non-significant between-group differences in unbiased analysis, the K/T ratio achieved an area under the receiver operator characteristic curve (AUC) of 0.667 and 81.5% sensitivity for TB diagnosis. Kynurenine, tryptophan, and IDO-1 demonstrated diagnostic AUCs of 0.667, 0.602, and 0.463, respectively. None of these biomarkers demonstrated high AUCs for treatment response. The AUC of the K/T ratio was lower than biomarkers identified in unbiased analysis, but improved sensitivity over existing commercial assays for pediatric TB diagnosis. Conclusions: Plasma kynurenine and the K/T ratio may be useful biomarkers for pediatric TB. Ongoing studies in geographically diverse populations will determine optimal use of these biomarkers worldwide.