Associations between systemic inflammation, mycobacterial loads in sputum and radiological improvement after treatment initiation in pulmonary TB patients from Brazil: a prospective cohort study

The levels of soluble CD137 are increased in tuberculosis patients and associated with disease severity and prognosis

Tuberculosis (TB) was the leading cause of death from a single infectious agent before the coronavirus pandemic. Therefore, it is important to search for severity biomarkers and devise appropriate therapies. A total of 139 pulmonary TB (PTB) patients and 80 healthy controls (HCs) were recruited for plasma soluble CD137 (sCD137) detection through ELISA. Moreover, pleural effusion sCD137 levels were measured in 85 TB patients and 36 untreated lung cancer patients. The plasma cytokine levels in 64 patients with PTB and blood immune cell subpopulations in 68 patients with PTB were analysed via flow cytometry. Blood sCD137 levels were higher in PTB patients (p = 0.012) and correlated with disease severity (p = 0.0056). The level of sCD137 in tuberculous pleurisy effusion (TPE) was markedly higher than that in malignant pleurisy effusion (p = 0.018). Several blood cytokines, such as IL-6 (p = 0.0147), IL-8 (p = 0.0477), IP-10 (p ≤ 0.0001) and MCP-1 (p = 0.0057), and some laboratory indices were significantly elevated in severe PTB (SE) patients, but the percentages of total lymphocytes (p = 0.002) and cytotoxic T cells (p = 0.036) were significantly lower in SE patients than in non-SE patients. In addition, the sCD137 level was negatively correlated with the percentage of total lymphocytes (p = 0.0008) and cytotoxic T cells (p = 0.0021), and PTB patients with higher plasma sCD137 levels had significantly shorter survival times (p = 0.0041). An increase in sCD137 is a potential biomarker for severe TB and indicates a poor prognosis.

A blood-based 3-gene signature score for therapeutic monitoring in patients with pulmonary tuberculosis

OBJECTIVE

To assess the validity of Xpert Tuberculosis Fingerstick score for monitoring treatment response and analyze factors influencing its performance.

METHODS

122 adults with pulmonary tuberculosis were recruited and stratified into three cohorts: Diabetic-drug-susceptible-TB (DM-TB), Non-diabetic-drug-susceptible-TB (NDM-TB) and Non-diabetic Multidrug-resistant TB (MDR-TB). Fingerstick blood specimens were tested at treatment initiation (M0) and the end of the first (M1), second (M2), and sixth month (M6) to generate a TB-score.

RESULTS

The TB-score in all participants yielded an AUC of 0.707 (95% CI: 0.579-0.834) at M2 when its performance was evaluated against sputum culture conversion. In all non-diabetes patients, the AUC reached 0.88 (95% CI: 0.756-1.000) with an optimal cut-off value of 1.95 at which sensitivity was 90.0% (95% CI: 59.6-98.2%) and specificity was 81.3% (95% CI: 70.0-88.9%). The mean TB score was higher in patients with low bacterial loads (n = 31) than those with high bacterial loads (n = 91) at M0, M1, M2, and M6, and was higher in non-cavitary patients (n = 71) than those with cavitary lesions (n = 51) at M0, M1, and M2.

CONCLUSION

Xpert TB-score shows promising predictive value for culture conversion in non-diabetic TB patients. Sputum bacterial load and lung cavitation status have an influence on the value of TB score.

Circulating Biomarkers, Fraction of Exhaled Nitric Oxide, and Lung Function in Patients With Human Immunodeficiency Virus and Tuberculosis

BACKGROUND

Identification of proinflammatory factors responding to Mycobacterium tuberculosis is important to reduce long-term sequelae of pulmonary tuberculosis (TB).

METHODS

We examined the association between plasma biomarkers, the fraction of exhaled nitric oxide (FeNO), and lung function among a prospective cohort of 105 adults newly diagnosed with TB/human immunodeficiency virus (HIV) in South Africa. Participants were followed for 48 weeks from antiretroviral therapy (ART) initiation with serial assessments of plasma biomarkers, FeNO, lung function, and respiratory symptoms. Linear regression and generalized estimating equations were used to examine the associations at baseline and over the course of TB treatment, respectively.

RESULTS

At baseline, higher FeNO levels were associated with preserved lung function, whereas greater respiratory symptoms and higher interleukin (IL)-6 plasma levels were associated with worse lung function. After ART and TB treatment initiation, improvements in lung function were associated with increases in FeNO (rate ratio [RR] = 86 mL, 95% confidence interval [CI] = 34-139) and decreases in IL-6 (RR = -118 mL, 95% CI = -193 to -43) and vascular endothelial growth factor ([VEGF] RR = -178 mL, 95% CI = -314 to -43).

CONCLUSIONS

Circulating IL-6, VEGF, and FeNO are associated with lung function in adults being treated for TB/HIV. These biomarkers may help identify individuals at higher risk for post-TB lung disease and elucidate targetable pathways to modify the risk of chronic lung impairment among TB survivors.

Evaluation of Systemic Inflammation Before and After Standard Anti-tuberculosis Treatment in Patients With Active Pulmonary Tuberculosis and Diabetes Mellitus

Background Diabetes mellitus (DM) is a common comorbidity of active pulmonary tuberculosis (APTB) that increases the risk of treatment failure during anti-tuberculosis chemotherapy. Evaluating systemic inflammatory response could help determine differences in response to treatment between APTB patients and those with APTB and DM. Methodology To explore changes in systemic inflammation, measured by a set of inflammatory mediators in subjects with APTB and TBDM before and after six months of anti-tuberculosis chemotherapy, 30 APTB and nine TBDM subjects underwent cytokine testing, including interleukin (IL)-6, IL-8, IL-10, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta 1 (TGF-β1) by enzyme-linked immunosorbent assay, C-reactive protein by nephelometry, and sialic acid by colorimetric assay at baseline and following six months of standard anti-tuberculosis treatment. Sputum smear microscopy or molecular biology (Xpert MTB/RIF) was used for diagnosis, and sputum smear microscopy was performed monthly during the treatment of the patient with pulmonary tuberculosis to evaluate his evolution. Principal component analysis examined changes in the inflammatory status. Results Both groups showed negative sputum smear microscopy in the sixth month after starting anti-tuberculosis chemotherapy. TGF-β1 was found to be significantly higher in subjects with TBDM before treatment compared to APTB patients (p<0.001), and systemic inflammation continued only in TBDM subjects after treatment (accumulation and persistence of inflammatory mediators like IL-6, IL-8, IL-10, IFN-γ, TNF-α, TGF-β1, C-reactive protein, and sialic acid in blood). On the other hand, the mediators IFN-γ, C-reactive protein, and total sialic acid were found to be most influential in distinguishing pre- and post-treatment inflammatory response in subjects with APTB without DM. Conclusions Inflammatory mediators analyzed in combination, including IFN-γ, CRP, and total sialic acid, may be useful in evaluating the systemic inflammatory response in subjects with APTB and TBDM before and after anti-tuberculosis treatment. Determining these mediators revealed persistent systemic inflammation in TBDM subjects after six months of standard tuberculosis treatment, despite negative sputum smear microscopy results and good glycemic control. This suggests a need for inflammation-modulating therapies during tuberculosis control. Finally, monitoring sputum smear microscopy results alongside the determination of proposed inflammatory mediators (IFN-γ, CRP, and total sialic acid) are effective in evaluating the response to anti-tuberculosis treatment in APTB subjects without DM, warranting further investigation.

Evaluation of the Cepheid 3-gene host response blood test for tuberculosis diagnosis and treatment response monitoring in a primary-level clinic in rural China

A rapid, accurate, non-sputum-based triage test for diagnosing tuberculosis (TB) is a high-priority need. Cepheid developed a novel prototype blood test, Xpert Mycobacterium tuberculosis Host Response (Xpert-MTB-HR), which generates a TB score based on the mRNA expression of three genes. We conducted a case-control study with prospective recruitment to evaluate its accuracy in the clinic of the Wusheng County Centers for Disease Prevention and Control in China. We enrolled 149 TB patients, 248 other respiratory diseases (ORD) patients, and 193 healthy controls. In addition, whole-blood samples taken from TB patients after 2, 5, and 6 months of treatment were tested with Xpert-MTB-HR to evaluate its ability to monitor treatment response. Xpert-MTB-HR discriminated between TB and healthy controls with an area under the curve (AUC) of 0.912 (95% CI, 0.878-0.945). With the specificity of 70% envisioned for a triage test, its sensitivity was 90.1% (84.9%-94.6%). Xpert-MTB-HR discriminated between TB and ORD with an AUC of 0.798 (0.750-0.847), and at specificity of 70%, the sensitivity was only 75.8% (68.5%-82.8%). In patients determined by Ultra to have medium or high sputum bacillary loads, with specificity of 70%, the sensitivity for discriminating patients with TB from healthy controls was 100.0% (100.0-100.0) and from patients with ORD, 95.1% (89.8-100.0). The TB scores generally increased by 2 months of treatment and then remained stable. Xpert-MTB-HR met the criteria for a triage test to discriminate between TB and healthy controls, but not between TB and ORD, except when limited to patients with high sputum bacillary loads. Xpert-MTB-HR showed promise for monitoring response to treatment but needs to be further evaluated in larger prospective studies.

The cause-effect relation of tuberculosis on incidence of diabetes mellitus

Tuberculosis (TB) is one of the oldest human diseases and is one of the major causes of mortality and morbidity across the Globe. Mycobacterium tuberculosis (Mtb), the causal agent of TB is one of the most successful pathogens known to mankind. Malnutrition, smoking, co-infection with other pathogens like human immunodeficiency virus (HIV), or conditions like diabetes further aggravate the tuberculosis pathogenesis. The association between type 2 diabetes mellitus (DM) and tuberculosis is well known and the immune-metabolic changes during diabetes are known to cause increased susceptibility to tuberculosis. Many epidemiological studies suggest the occurrence of hyperglycemia during active TB leading to impaired glucose tolerance and insulin resistance. However, the mechanisms underlying these effects is not well understood. In this review, we have described possible causal factors like inflammation, host metabolic changes triggered by tuberculosis that could contribute to the development of insulin resistance and type 2 diabetes. We have also discussed therapeutic management of type 2 diabetes during TB, which may help in designing future strategies to cope with TB-DM cases.

Sleep-Disordered Breathing and Chronic Respiratory Infections: A Narrative Review in Adult and Pediatric Population

Sleep-disordered breathing (SDB) comprises different diseases characterized by abnormal respiratory patterns during sleep including obstructive sleep apnea. SDB prevalence and impact in patients with chronic respiratory infections have been only marginally studied. The purpose of this narrative review is to report the prevalence and impact of SDB in chronic respiratory infections, including cystic fibrosis (CF), bronchiectasis and mycobacterial infections, and explore the possible pathophysiological mechanisms. Common pathophysiological mechanisms, underlying SDB onset in all chronic respiratory infections, include inflammation, which plays a central role, chronic nocturnal cough and pain, excessive production of mucous plugs, presence of obstructive and/or restrictive ventilatory impairment, upper airways involvement, and comorbidities, such as alteration of nutritional status. SDB may affect about 50% of patients with bronchiectasis. The severity of the disease, e.g., patients colonized with P. aeruginosa and frequent exacerbators, as well as comorbidities, such as chronic obstructive pulmonary disease and primary ciliary dyskinesia, may impact SDB onset. SDB may also frequently complicate the clinical course of both children and adults with CF, impacting the quality of life and disease prognosis, suggesting that their routine assessment should be incorporated into the clinical evaluation of patients from the first stages of the disease regardless of suggestive symptoms, in order to avoid late diagnosis. Finally, although the prevalence of SDB in patients with mycobacterial infections is uncertain, extrapulmonary manifestations, particularly nasopharyngeal locations, and concomitant symptoms, such as body pain and depression, may act as atypical predisposing factors for their development.

Serum biomarkers in patients with unilateral or bilateral active pulmonary tuberculosis: Immunological networks and promising diagnostic applications

The present observational study was designed to characterize the integrative profile of serum soluble mediators to describe the immunological networks associated with clinical findings and identify putative biomarkers for diagnosis and prognosis of active tuberculosis. The study population comprises 163 volunteers, including 84 patients with active pulmonary tuberculosis/(TB), and 79 controls/(C). Soluble mediators were measured by multiplexed assay. Data analysis demonstrated that the levels of CCL3, CCL5, CXCL10, IL-1β, IL-6, IFN-γ, IL-1Ra, IL-4, IL-10, PDGF, VEGF, G-CSF, IL-7 were increased in TB as compared to C. Patients with bilateral pulmonary involvement/(TB-BI) exhibited higher levels of CXCL8, IL-6 and TNF with distinct biomarker signatures (CCL11, CCL2, TNF and IL-10) as compared to patients with unilateral infiltrates/(TB-UNI). Analysis of biomarker networks based in correlation power graph demonstrated small number of strong connections in TB and TB-BI. The search for biomarkers with relevant implications to understand the pathogenetic mechanisms and useful as complementary diagnosis tool of active TB pointed out the excellent performance of single analysis of IL-6 or CXCL10 and the stepwise combination of IL-6 → CXCL10 (Accuracy = 84 %; 80 % and 88 %, respectively). Together, our finding demonstrated that immunological networks of serum soluble biomarkers in TB patients differ according to the unilateral or bilateral pulmonary involvement and may have relevant implications to understand the pathogenetic mechanisms involved in the clinical outcome of Mtb infection.

Cardiovascular Involvement in Tuberculosis: From Pathophysiology to Diagnosis and Complications-A Narrative Review

Although primarily a lung disease, extra-pulmonary tuberculosis (TB) can affect any organ or system. Of these, cardiovascular complications associated with disease or drug toxicity significantly worsen the prognosis. Approximately 60% of patients with TB have a cardiovascular disease, the most common associated pathological entities being pericarditis, myocarditis, and coronary artery disease. We searched the electronic databases PubMed, MEDLINE, and EMBASE for studies that evaluated the impact of TB on the cardiovascular system, from pathophysiological mechanisms to clinical and paraclinical diagnosis of cardiovascular involvement as well as the management of cardiotoxicity associated with antituberculosis medication. The occurrence of pericarditis in all its forms and the possibility of developing constrictive pericarditis, the association of concomitant myocarditis with severe systolic dysfunction and complication with acute heart failure phenomena, and the long-term development of aortic aneurysms with risk of complications, as well as drug-induced toxicity, pose complex additional problems in the management of patients with TB. In the era of multidisciplinarity and polymedication, evidence-based medicine provides various tools that facilitate an integrative management that allows early diagnosis and treatment of cardiac pathologies associated with TB.

Tuberculosis-Associated Anemia: A Narrative Review

Tuberculosis (TB) is an airborne illness that induces systemic inflammation. It often affects the lungs causing cough, fever, and chest pain. A commonly associated comorbid condition in TB is anemia. This review article has summarized various studies with an aim to gain a better understanding of pathogenesis and the role of cytokines that contribute to the development of anemia in TB. The study has gathered risk factors that enhance the likelihood of TB patients acquiring anemia. It has reviewed therapeutic modalities such as antitubercular therapy and iron therapy in an attempt to find which of them are effective in reducing the severity of anemia. This review article has also emphasized the importance of measuring hepcidin and ferritin and has touched upon the investigations that can be easily implemented.

Biomarkers that correlate with active pulmonary tuberculosis treatment response: a systematic review and meta-analysis

Current WHO recommendations for monitoring treatment response in adult pulmonary tuberculosis (TB) are sputum smear microscopy and/or culture conversion at the end of the intensive phase of treatment. These methods either have suboptimal accuracy or a long turnaround time. There is a need to identify alternative biomarkers to monitor TB treatment response. We conducted a systematic review of active pulmonary TB treatment monitoring biomarkers. We screened 9,739 articles published between 1 January 2008 and 31 December 2020, of which 77 met the inclusion criteria. When studies quantitatively reported biomarker levels, we meta-analyzed the average fold change in biomarkers from pretreatment to week 8 of treatment. We also performed a meta-analysis pooling the fold change since the previous time point collected. A total of 81 biomarkers were identified from 77 studies. Overall, these studies exhibited extensive heterogeneity with regard to TB treatment monitoring study design and data reporting. Among the biomarkers identified, C-reactive protein (CRP), interleukin-6 (IL-6), interferon gamma-induced protein 10 (IP-10), and tumor necrosis factor alpha (TNF-α) had sufficient data to analyze fold changes. All four biomarker levels decreased during the first 8 weeks of treatment relative to baseline and relative to previous time points collected. Based on limited data available, CRP, IL-6, IP-10, and TNF-α have been identified as biomarkers that should be further explored in the context of TB treatment monitoring. The extensive heterogeneity in TB treatment monitoring study design and reporting is a major barrier to evaluating the performance of novel biomarkers and tools for this use case. Guidance for designing and reporting treatment monitoring studies is urgently needed.

Baseline IL-6 is a biomarker for unfavorable tuberculosis treatment outcomes: a multi-site discovery and validation study

Background

Biomarkers of unfavorable tuberculosis treatment outcomes are needed to accelerate new drug and regimen development. Whether plasma cytokine levels can predict unfavorable tuberculosis treatment outcomes is unclear.

Methods

We identified and internally validated the association between 20 a-priori selected plasma inflammatory markers and unfavorable treatment outcomes of failure, recurrence and all-cause mortality among adults with drug-sensitive pulmonary tuberculosis in India. We externally validated these findings in two independent cohorts of predominantly diabetic and HIV coinfected tuberculosis patients in India and South Africa, respectively.

Results

Pre-treatment IFN-γ, 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 to controls. External validation among predominantly diabetic tuberculosis patients found an association between pre-treatment IL-6 concentrations and subsequent recurrence and death. Similarly, external validation among predominantly HIV coinfected tuberculosis patients found an association between pre-treatment IL-6 concentrations and subsequent treatment failure and death. In a pooled analysis of 363 tuberculosis cases from the Indian and South African validation cohorts, high pre-treatment IL-6 concentrations were associated with higher risk of failure (adjusted odds ratio [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 comprising of low BMI, high smear grade and cavitation improved model performance by 15 percent (C-statistic of 0.66 versus 0.76, p=0.02).

Conclusion

Pre-treatment IL-6 is a biomarker for unfavorable tuberculosis treatment outcomes. Future studies should identify optimal IL-6 concentrations for point-of-care risk prediction.

The Effect of Diabetes and Prediabetes on Anti-tuberculosis Treatment Outcomes: A Multi-center Prospective Cohort Study

BACKGROUND

It is unclear whether diabetes or prediabetes affect unfavorable treatment outcomes and death in people with tuberculosis (PWTB).

METHODS

Culture-confirmed drug-susceptible PWTB, enrolled in Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil between 2015-2019 (n=643) were stratified based on glycemic status according to baseline glycated hemoglobin. Unfavorable TB outcome was defined as treatment failure or modification, recurrence or death; favorable outcome was cure or treatment completion. We corroborated the findings using data from PWTB reported to the Brazilian National System of Diseases Notification (SINAN) during 2015-2019 (n=20,989). Logistic regression models evaluated associations between glycemic status and outcomes.

RESULTS

In both cohorts, in univariate analysis, unfavorable outcomes were more frequently associated with smoking, illicit drug use and HIV infection. Diabetes, but not prediabetes, was associated with unfavorable outcomes in the RePORT-Brazil (adjusted Relative Risk [aRR]: 2.45, p<0.001) and SINAN (aRR: 1.76, p<0.001) cohorts. Furthermore, diabetes was associated with high risk of death (during TB treatment) in both RePORT-Brazil (aRR:2.16, p=0.040) and SINAN (aRR:1.93, p= 0.001).

CONCLUSION

Diabetes was associated with an increased risk of unfavorable outcomes and mortality in Brazilian PWTB. Interventions to improve tuberculosis treatment outcomes in persons with diabetes are needed.

The association of atherosclerotic cardiovascular disease and statin use with inflammation and treatment outcomes in tuberculosis

Tuberculosis (TB) and atherosclerotic cardiovascular disease (ASCVD) have a close epidemiological and pathogenetic overlap. Thus, it becomes essential to understand the relationship between ASCVD and TB outcomes. From our retrospective cohort on drug-susceptible TB patients at the National Taiwan University Hospital, we assessed the association of pre-existing ASCVD (coronary artery disease (CAD) and atherothrombotic stroke (ATS)) with 9-month all-cause and infection-related mortality and the extent of mediation by systemic inflammatory markers. We determined the effect of pre-existing ASCVD on 2-month sputum microbiological status. Among ASCVD patients, we assessed the association of statin use on mortality. Nine-month all-cause mortality was higher in CAD patients with prior acute myocardial infarction (CAD⁺AMI⁺) (adjusted HR 2.01, 95%CI 1.38–3.00) and ATS patients (aHR 2.79, 95%CI 1.92–4.07) and similarly, for infection-related mortality was higher in CAD⁺AMI⁺ (aHR 1.95, 95%CI 1.17–3.24) and ATS (aHR 2.04, 95%CI 1.19–3.46) after adjusting for confounding factors. Pre-existing CAD (AMI^- or AMI⁺) or ATS did not change sputum culture conversion or sputum smear AFB positivity at 2 months. The CAD⁺AMI⁺ group had significantly higher levels of CRP at TB diagnosis in the multivariable linear regression analysis (Adjusted B(SE) 1.24(0.62)). CRP mediated 66% (P = 0.048) and 25% (P = 0.033) of the association all-cause mortality with CAD⁺AMI⁻ and CAD⁺AMI⁺, respectively. In summary, patients with ASCVD have higher hazards of 9-month all-cause and infection-related mortality, with elevated serum inflammation mediating one to three-quarters of this association when adjusted for confounders. Statin use was associated with lower all-cause mortality among patients with ASCVD.

Beneficial effect of long-chain n-3 polyunsaturated fatty acid supplementation on tuberculosis in mice

Intakes of the omega-3 essential fatty acids (n-3 EFAs) are low in the general adult population, with high n-6/n-3 polyunsaturated fatty acid (PUFA) ratios and the accompanying suboptimal n-3 PUFA status. Eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) have antibacterial and inflammation-resolving effects in tuberculosis (TB). However, whether switching to a diet with optimum n-3 EFA intake after the infection has comparable benefits has not been investigated. We aimed to compare the effects of a diet with sufficient n-3 EFA content in an acceptable n-6/n-3 PUFA ratio for rodents ((n-3)eFAS group) with those on the same diet supplemented with EPA and DHA (EPA/DHA group) in Mycobacterium tuberculosis (Mtb)-infected C3HeB/FeJ mice with a low n-3 PUFA status. Mice were conditioned on an n-3 PUFA-deficient diet with a high n-6/n-3 PUFA ratio for 6 weeks before Mtb infection and randomized to either (n-3)eFAS or EPA/DHA diets 1 week post-infection for 3 weeks. At endpoint, EPA and DHA compositions were higher and arachidonic acid, osbond acid, and total n-6 LCPUFAs lower in all lipid pools measured in the EPA/DHA group (all P < 0.001). Percentage body weight gain was higher (P = 0.017) and lung bacterial load lower (P < 0.001) in the EPA/DHA group. Additionally, the EPA/DHA group had a more pro-resolving lung lipid mediator profile and lower lung in IL-1α and IL-1β concentrations (P = 0.023, P = 0.049). Inverse correlations were found between the lung and peripheral blood mononuclear cell EPA and DHA and selected pro-inflammatory cytokines. These are the first findings that indicate that EPA/DHA supplementation provides benefits superior to a diet with sufficient n-3 EFAs concerning bacterial killing, weight gain and lung inflammation resolution in Mtb-infected mice with a low n-3 PUFA status. Therefore, EPA and DHA may be worth considering as adjunct TB treatment.

Prediction of Treatment Outcome with Inflammatory Biomarkers after 2 Months of Therapy in Pulmonary Tuberculosis Patients: Preliminary Results

Pro-inflammatory mediators play an important role in the pathogenesis of pulmonary tuberculosis. Consecutively, 26 pulmonary tuberculosis patients were enrolled in our study based on the exclusion criteria. We have used Spearman’s correlation analysis, hierarchical clustering and regression modelling to evaluate the association of 11 biomarkers with culture status after antituberculosis treatment. The results of our study demonstrated that six inflammatory biomarkers of 11, C-reactive protein (CRP), white blood cells (WBC), neutrophils, interferon gamma inducible protein 10, C-reactive protein (CRP) to albumin ratio (CAR) and neutrophil to albumin ratio (NAR), were significantly associated with culture negativity. The predictive ability of a composite model of seven biomarkers was superior to that of any single biomarker based on area under the receiver operating characteristic curve (AUC) analysis, indicating an excellent prediction efficacy (AUC:0.892; 95% CI:0.732-1.0). We also found that the highest significant trends and lower levels of CRP and IP-10 were observed in the two-month treated tuberculosis (TB) patients. We believe that our study may be valuable in providing preliminary results for an additional strategy in monitoring and management of the clinical outcome of pulmonary tuberculosis. Using a panel of predictors added a superior value in predicting culture status after anti-TB therapy.

Potential biomarker enhancing the activity of tuberculosis, hsa-miR-346

OBJECTIVES

To determine the usefulness of hsa-miR-346, a potential biomarker enhancing the activity of non-tuberculous mycobacterial diseases, as a biomarker of tuberculosis activity.

METHODS

We investigated whether hsa-miR-346 is secreted by human macrophages infected with Mycobacterium tuberculosis (M. tuberculosis) in an in vitro study. In addition, a cross-sectional study was conducted first to evaluate whether serum hsa-miR-346 is elevated in patients with tuberculosis compared with that in healthy individuals. Second, we conducted a retrospective study to evaluate whether anti-tuberculosis treatment reduces serum hsa-miR-346 levels.

RESULTS

Log hsa-miR-346 levels were significantly elevated in the supernatant of human macrophages infected with M. tuberculosis in a dose-dependent manner. The mean serum log hsa-miR-346 levels were -15.48 (-15.76 to -15.21) in patients with tuberculosis and -16.12 (-16.29 to -15.95) in healthy volunteers, which significantly differed. In addition, hsa-miR-346 significantly decreased at 2 months from starting an anti-tuberculosis treatment.

CONCLUSIONS

We consider hsa-miR-346 as a potential biomarker enhancing the tuberculosis activity.

Inflammatory profile of patients with tuberculosis with or without HIV-1 co-infection: a prospective cohort study and immunological network analysis

Background

HIV-1 mediated dysregulation of the immune response to tuberculosis and its effect on the response to antitubercular therapy (ATT) is incompletely understood. We aimed to analyse the inflammatory profile of patients with tuberculosis with or without HIV-1 co-infection undergoing ATT, with specific focus on the effect of ART and HIV-1 viraemia in those co-infected with HIV-1.

Methods

In this prospective cohort study and immunological network analysis, a panel of 38 inflammatory markers were measured in the plasma of a prospective patient cohort undergoing ATT at Khayelitsha Site B clinic, Cape Town, South Africa. We recruited patients with sputum Xpert MTB/RIF-positive rifampicin-susceptible pulmonary tuberculosis. Patients were excluded from the primary discovery cohort if they were younger than 18 years, unable to commence ATT for any reason, pregnant, had unknown HIV-1 status, were unable to consent to study participation, were unable to provide baseline sputum samples, had more than three doses of ATT, or were being re-treated for tuberculosis within 6 months of their previous ATT regimen. Plasma samples were collected at baseline (1–5 days after commencing ATT), week 8, and week 20 of ATT. We applied network and multivariate analysis to investigate the dynamic inflammatory profile of these patients in relation to ATT and by HIV status. In addition to the discovery cohort, a validation cohort of patients with HIV-1 admitted to hospital with CD4 counts less than 350 cells per μL and a high clinical suspicion of new tuberculosis were recruited.

Findings

Between March 1, 2013, and July 31, 2014, we assessed a cohort of 129 participants (55 [43%] female and 74 [57%] male, median age 35·1 years [IQR 30·1–43·7]) and 76 were co-infected with HIV-1. HIV-1 status markedly influenced the inflammatory profile regardless of ATT duration. HIV-1 viral load emerged as a major factor driving differential inflammatory marker expression and having a strong effect on correlation profiles observed in the HIV-1 co-infected group. Interleukin (IL)-17A emerged as a key correlate of HIV-1-induced inflammation during HIV–tuberculosis co-infection.

Interpretation

Our findings show the effect of HIV-1 co-infection on the complexity of plasma inflammatory profiles in patients with tuberculosis. Through network analysis we identified IL-17A as an important node in HIV–tuberculosis co-infection, thus implicating this cytokine’s capacity to correlate with, and regulate, other inflammatory markers. Further mechanistic studies are required to identify specific IL-17A-related inflammatory pathways mediating immunopathology in HIV–tuberculosis co-infection, which could illuminate targets for future host-directed therapies.

Funding

National Institutes of Health, The Wellcome Trust, UK Research and Innovation, Cancer Research UK, European and Developing Countries Clinical Trials Partnership, and South African Medical Research Council.

Evaluation of prognostic significance of hematological profiles after the intensive phase treatment in pulmonary tuberculosis patients from Romania

We evaluated in this cohort study the predictive ability of 23 peripheral blood parameters and ratios for treatment outcomes after the 2-month intensive phase in patients with PTB. In 63 patients out of 90 that turned culture negative, a significant decrease in white blood cell count, neutrophils, monocyte, hemoglobin, platelet, plateletcrit, erythrocyte sedimentation rate, MLR, NLR, PLR and SII values after anti-TB therapy compared to pretreatment was observed (p <0.001). Logistic regression analysis generated a model of predictors consisting of nine covariates. Spearman’s correlation analysis revealed significant positive correlations between NLR with NEU (r = 0.79, p<0.01), SII with NEU (r = 0.846, p<0.01), PLT with SII (r = 0.831, p<0.01), PLT with PCT (r = 0.71, p<0.01) and MPV with P-LCR (r = 0,897, p<0.01) in 63 patients out of 90 that turned culture negative after 2 months of treatment. ROC curve analysis indicated that all areas under the curve (AUC) revealed no statistically significant results, except lymphocyte for culture conversion. In summary, here we observed a set of hematological parameters that declined significantly as the disease was treated in patients that turned culture negative. Despite some limitations, our findings are useful for further studies aiming to identify hematological profiles that could predict the treatment outcome.

An Inflammatory Composite Score Predicts Mycobacterial Immune Reconstitution Inflammatory Syndrome in People with Advanced HIV: A Prospective International Cohort Study

BACKGROUND

Immune reconstitution inflammatory syndrome (IRIS) is a common cause of morbidity among people with human immunodeficiency virus (PWH) who initiate antiretroviral therapy (ART) with severe lymphopenia. Easily accessible tools that reliably predict emergence and elucidate pathogenesis of IRIS are needed to facilitate improved clinical management.

METHODS

Plasma levels of biomarkers were measured before ART initiation in a large multinational cohort of ART-naive PWH with severe immunosuppression (CD4+ count <100 cells/mm3) in United States, Kenya, and Thailand. We performed a series of multiparametric analyses of inflammatory and clinical biomarkers and developed a composite score merging relevant biomarkers for use in a prediction model.

RESULTS

We identified a distinct baseline inflammatory profile and changes in inflammatory networks among biomarkers in participants who subsequently developed mycobacterial or viral IRIS. We also developed a composite score incorporating biomarkers associated with IRIS (interleukin-6 [IL-6], IL-10, IL-27, sCD14, interferon-γ, tumor necrosis factor-α, hyaluronic acid, D-dimer, body mass index, and hemoglobin) that accurately predicted mycobacterial IRIS and death in this cohort.

CONCLUSIONS

Systemic inflammatory profiles in PWH with severe immunosuppression are predictive of IRIS. Composite scores for the prediction of mycobacterial IRIS and death could be useful for risk stratification in PWH and lymphopenia initiating ART.

CLINICAL TRIALS REGISTRATION

NCT00286767.

A valuable computed tomography-based new diagnostic tool for severe chest lesions in active pulmonary tuberculosis: combined application of influencing factors

The objective of the present investigation was to explore the influencing factors and value of computed tomography (CT) for diagnosing severe chest lesions in active pulmonary tuberculosis (APTB). This retrospective investigation included 463 patients diagnosed with APTB. Relevant clinical features were collected. Patients were assigned to mild/moderate group or advanced group depending on the lesion severity on chest CT, severe chest CT lesion refers to the moderately dense or less diffuse lesion that exceeds the total volume of one lung, or the dense fusion lesion greater than one third of the volume of one lung, or the lesion with cavity diameter ≥4 cm. Independent risk factors for severe lesions were determined by univariate and multivariate logistic regression analyses, and the diagnostic efficiency of the risk factors was assessed by receiver operating characteristic curve (ROC). Chest CT demonstrated that there were 285 (61.56%) cases with severe lesions; multivariate Logistic regression analysis showed dust exposure [odds ratio (OR) = 4.108, 95% confidence interval (CI) 2.416–6.986], patient classification (OR = 1.792, 95% CI 1.067–3.012), age (OR = 1.018, 95% CI 1.005–1.030), and albumin-globulin ratio (OR = 0.179, 95% CI 0.084–0.383) to be independently correlated with severe lesions on chest CT. ROC curve analysis showed the cutoff values of age, albumin-globulin ratio and combined score to be 39 years, 0.918 and −0.085, respectively. The predictive value of combined score area under the curve 0.753 (95% CI 0.708–0.798) was higher than that of any single factor. The combined score of these four factors further improved the predictive efficacy.

Lipid mediators of inflammation and Resolution in individuals with tuberculosis and tuberculosis-Diabetes

Individuals with concurrent tuberculosis (TB) and Type 2 diabetes (DM) have a higher risk of adverse outcomes. To better understand potential immunological differences, we utilized a comprehensive panel to characterize pro-inflammatory and pro-resolving (i.e., mediators involved in the resolution of inflammation) lipid mediators in individuals with TB and TB-DM. A nested cross-sectional study of 40 individuals (20 newly diagnosed DM and 20 without DM) was conducted within a cohort of individuals with active drug-susceptible treatment-naïve pulmonary TB. Lipid mediators were quantified in serum samples through lipid mediator profiling. We conducted correlation-based analysis of these mediators. Overall, the arachidonic acid-derived leukotriene and prostaglandin families were the most abundant pro-inflammatory lipid mediators, while lipoxins and maresins families were the most abundant pro-resolving lipid mediators in individuals with TB and TB-DM. Individuals with TB-DM had increased correlations and connectivity with both pro-inflammatory and pro-resolving lipid mediators compared to those with TB alone. We identified the most abundant lipid mediator metabolomes in circulation among individuals with TB and TB-DM; in addition, our data shows a substantial number of significant correlations between both pro-inflammatory and pro-resolving lipid mediators in individuals with TB-DM, delineating a molecular balance that potentially defines this comorbidity.

Trends in C-Reactive Protein, D-Dimer, and Fibrinogen during Therapy for HIV-Associated Multidrug-Resistant Tuberculosis

HIV-positive adults on treatment for multi drug-resistant tuberculosis (MDR-TB) experience high mortality. Biomarkers of HIV/MDR-TB treatment response may enable earlier treatment modifications that improve outcomes. To determine whether changes in C-reactive protein (CRP), D-dimer, and fibrinogen were associated with treatment outcome among those with HIV/MDR-TB coinfection, we studied 20 HIV-positive participants for the first 16 weeks of MDR-TB therapy. Serum CRP, fibrinogen, and D-dimer were measured at baseline and serially while on treatment. At baseline, all biomarkers were elevated above normal levels, with median CRP 86.15 mg/L (interquartile range [IQR] 29.25-149.32), D-dimer 0.85 µg/mL (IQR 0.34-1.80), and fibrinogen 4.11 g/L (IQR 3.75-6.31). C-reactive protein decreased significantly within 10 days of treatment initiation and fibrinogen within 28 days; D-dimer did not change significantly. Five (25%) participants died after a median of 32 days. Older age (median age of 38y among survivors and 54y among deceased, P = 0.008) and higher baseline fibrinogen (3.86 g/L among survivors and 6.37 g/L among deceased, P = 0.02) were significantly associated with death. After adjusting for other measured variables, higher CRP concentrations at the beginning of each measurement interval were significantly associated with a higher risk of death during that interval. Trends in fibrinogen and CRP may be useful for evaluating early response to treatment among individuals with HIV/MDR-TB coinfection.

Changes in inflammatory protein and lipid mediator profiles persist after antitubercular treatment of pulmonary and extrapulmonary tuberculosis: A prospective cohort study

BACKGROUND

The identification of meaningful biomarkers of tuberculosis (TB) has potential to improve diagnosis, disease staging and prediction of treatment outcomes. It has been shown that active pulmonary TB (PTB) is associated with qualitative and quantitative changes in systemic immune profile, suggesting a chronic inflammatory imbalance. Here we characterized the profile of PTB and extrapulmonary TB (EPTB) in a prospective cohort study.

METHODS

We measured a panel of 27 inflammatory cytokines, soluble receptors, and lipid mediators in peripheral blood from patients with PTB or EPTB from a prospective clinical study in China. Multidimensional analyses were performed to describe associations between plasma levels of biomarkers and different TB disease presentation profiles.

RESULTS

Mycobacterium tuberculosis infection induced changes in both the expression and correlation profiles of plasma mediators of inflammation in patients with PTB compared to those with EPTB. Increases in mycobacterial loads in sputum smears were associated with rises in concentrations of several molecules involved in TB pathogenesis, such as IL-1β, IFN-α, IL-10 and PGF2α. Moreover, PTB patients presenting with severe disease exhibited a distinct inflammatory profile hallmarked by heightened levels of TNF-α, IL-1β, IL17, IL-18 and IL-27. Interestingly, while antitubercular treatment (ATT) resulted in early changes of plasma concentrations of markers in PTB, changes were delayed in EPTB patients. Exploratory analyses of the molecular degree of perturbation (MDP) of the inflammatory mediators before and during ATT suggested the occurrence of infection and/or treatment-induced long lasting "inflammatory imprinting" of biomarker profiles in TB. At 24 weeks post ATT commencement, markers underlying the observed increases in MDP scores were IL-27 in PTB and IL-1β in EPTB patients.

CONCLUSION

Our findings describe systemic and durable changes in the concentrations of inflammatory cytokines and lipid mediators in both PTB and EPTB and emphasize the role of M. tuberculosis bacterial burden and site of disease in modulating patient immune biomarkers.

Molecular degree of perturbation of plasma inflammatory markers associated with tuberculosis reveals distinct disease profiles between Indian and Chinese populations

Tuberculosis (TB) is a chronic inflammatory disease caused by Mycobacterium tuberculosis infection which causes tremendous morbidity and mortality worldwide. Clinical presentation of TB patients is very diverse and disease heterogeneity is associated with changes in biomarker signatures. Here, we compared at the molecular level the extent of individual inflammatory perturbation of plasma protein and lipid mediators associated with TB in patients in China versus India. We performed a cross-sectional study analyzing the overall degree of inflammatory perturbation in treatment-naïve pulmonary TB patients and uninfected individuals from India (TB: n = 97, healthy: n = 20) and China (TB: n = 100, healthy: n = 11). We employed the molecular degree of perturbation (MDP) adapted to plasma biomarkers to examine the overall changes in inflammation between these countries. M. tuberculosis infection caused a significant degree of molecular perturbation in patients from both countries, with higher perturbation detected in India. Interestingly, there were differences in biomarker perturbation patterns and the overall degree of inflammation. Patients with severe TB exhibited increased MDP values and Indian patients with this condition exhibited even higher degree of perturbation compared to Chinese patients. Network analyses identified IFN-α, IFN-β, IL-1RI and TNF-α as combined biomarkers that account for the overall molecular perturbation in the entire study population. Our results delineate the magnitude of the systemic inflammatory perturbation in pulmonary TB and reveal qualitative changes in inflammatory profiles between two countries with high disease prevalence.

International collaboration among medical societies is an effective way to boost Latin American production of articles on tuberculosis

Objective:

Most studies of tuberculosis originate from high-income countries with a low incidence of tuberculosis. A review of the scientific production on tuberculosis in Latin American countries, most of which are low- or middle-income countries (some with high or intermediate tuberculosis incidence rates), would improve the understanding of public health challenges, clinical needs, and research priorities. The aims of this systematic review were to determine what has been published recently in Latin America, to identify the leading authors involved, and to quantify the impact of international collaborations.

Methods:

We used PubMed to identify relevant manuscripts on pulmonary tuberculosis (PTB), drug-resistant tuberculosis (DR-TB), or multidrug-resistant tuberculosis (MDR-TB), published between 2013 and 2018. We selected only studies conducted in countries with an annual tuberculosis incidence of ≥ 10,000 reported cases and an annual MDR-TB incidence of ≥ 300 estimated cases, including Brazil, Peru, Mexico, Colombia, and Argentina. Articles were stratified by country, type, and topic.

Results:

We identified as eligible 395 studies on PTB and 188 studies on DR/MDR-TB-of which 96.4% and 96.8%, respectively, were original studies; 35.5% and 32.4%, respectively, had an epidemiological focus; and 52.7% and 36.2%, respectively, were conducted in Brazil. The recent Latin American Thoracic Association/European Respiratory Society/Brazilian Thoracic Association collaborative project boosted the production of high-quality articles on PTB and DR/MDR-TB in Latin America.

Conclusions:

Most of the recent Latin American studies on tuberculosis were conducted in Brazil, Mexico, or Peru. Collaboration among medical societies facilitates the production of scientific papers on tuberculosis. Such initiatives are in support of the World Health Organization call for intensified research and innovation in tuberculosis.

Tuberculosis-associated anemia is linked to a distinct inflammatory profile that persists after initiation of antitubercular therapy

Pulmonary tuberculosis (PTB) is associated with chronic inflammation and anemia. How anemia impacts systemic inflammation in PTB patients undergoing antitubercular therapy (ATT) is not fully understood. In the present study, data on several blood biochemical parameters were retrospectively analyzed from 118 PTB patients during the first 60 days of ATT. Multidimensional statistical analyses were employed to perform detailed inflammatory profiling of patients stratified by anemia status prior to treatment. Anemia was defined as hemoglobin levels <12.5 g/dL for female and <13.5 g/dL for male individuals. The findings revealed that most of anemia cases were likely caused by chronic inflammation. A distinct biosignature related to anemia was detected, defined by increased values of uric acid, C-reactive protein, and erythrocyte sedimentation rate. Importantly, anemic patients sustained increased levels of several biochemical markers at day 60 of therapy. Preliminary analysis failed to demonstrate association between persistent inflammation during ATT with frequency of positive sputum cultures at day 60. Thus, TB patients with anemia exhibit a distinct inflammatory profile, which is only partially reverted at day 60 of ATT.

Imbalance of NET and Alpha-1-Antitrypsin in Tuberculosis Patients Is Related With Hyper Inflammation and Severe Lung Tissue Damage

Background: Pulmonary tuberculosis (PTB) can lead to lung tissue damage (LTD) and compromise the pulmonary capacity of TB patients that evolve to severe PTB. The molecular mechanisms involved in LTD during anti-tuberculous treatment (ATT) remain poorly understood.

Methods and findings: We evaluated the role of neutrophil extracellular trap (NET) and the occurrence of LTD through chest radiographic images, the microbial load in sputum, and inflammatory serum profile (IL-12p40/p70, IL-8, IL-17A, IL-23, VEGF-A, MMP-1, and -8, galectin-3, citrunillated histone H3—cit-H3, alpha-1-antitrypsin—α1AT, C-reactive protein—CRP and albumin) in a cohort of 82 PTB patients before and after 60 days of ATT. Using univariate analysis, LTD was associated with neutrophilia and increase of several inflammatory proteins involved in the neutrophil-mediated response, being cit-H3 the more related to the event. In the multivariate analysis, neutrophilia and cit-H3 appear as directly related to LTD. The analysis of the ROC curve at day 60 presented AUC of 0.97 (95.0% CI 0.95–1). Interestingly, at day 0 of ATT, these biomarkers demonstrated fine relation with LTD showing an AUC 0.92 (95.0% CI 0.86–0.99). Despite of that, the same molecules have no impact in culture conversion during ATT.

Conclusions: Our data revealed that NETs may play a key role in the pathway responsible for non-specific inflammation and tissue destruction in PTB. High level of cit-H3 and low level of α1AT was observed in the serum of severe TB patients, suggesting a breakdown in the intrinsic control of NET-driven tissue damage. These data show a new insight to knowledge TB immunopathogenesis, the role of neutrophil and NET pathway. Likewise, we identified possible biomarkers to screening of PTB patients eligible to adjuvants therapies, as anti-inflammatories and alpha-1-antitrypsin.

Pseudomonas aeruginosa induces cellular senescence in lung tissue at the early stage of two-hit septic mice

We presume that severe secondary Pseudomonas aeruginosa (PA) infection can lead to cellular senescence in lung tissue and thus contribute to high mortality. We established a two-hit mouse model using cecal ligation and puncture (CLP) followed by sublethal PA lung infection. In lung tissue, increased infiltration of inflammatory cells, elevated lung injury and augmented cellular senescence was shown in mice with CLP followed by sublethal PA infection, and these observations reached a higher rank when higher (H) loads PA (PAO1) were administered to CLP mice (CLP + PAO1-H). Accordingly, oxidative stress-related element gp91phox and inflammation regulator NF-κB were greatly activated in CLP + PAO1-H mice compared to others. There was no obvious inflammation or cellular senescence in sham control, PAO1-infected mice. Consequently, CLP + PAO1-H mice had the highest expression levels of inflammatory cytokines IL-6, TNFα and iNOS among those groups. There was lower bacterial clearance ability in CLP + PAO1-H mice than in other mice. CLP + PAO1-H only had approximately 10% survival after 7 days of investigation and was much lower than others. In conclusion, higher mortality due to increased lung inflammation and cellular senescence are observed in mice with increased loads of PA infection secondary to CLP.

Clinical significance of Glasgow Prognostic Score in patients with tuberculous pleurisy

Background

The Glasgow Prognostic Score (GPS) reflects the host systemic inflammatory response and is a validated, independent prognostic factor for various malignancies. We investigated the clinical significance of the GPS in patients with tuberculosis (TB) pleurisy, focusing on treatment outcomes including paradoxical response (PR).

Methods

This was a retrospective study performed between January 2010 and December 2015 in two referral and university hospitals in South Korea, with intermediate incidences of TB. In all, 462 patients with TB pleurisy were registered in the study. The patients were classified into three groups based on GPS score, as follows: (I) GPS of 2, elevated CRP level (>1.0 mg/dL) and hypoalbuminemia (<3.5 g/dL); (II) GPS of 1, elevated CRP level or hypoalbuminemia; and (III) GPS of 0, neither elevated CRP level nor hypoalbuminemia.

Results

A total of 367 patients with TB pleurisy were finally included. PR occurred in 102 (27.8%) patients after a mean of 75 days following initiation of anti-TB treatment. The proportion of PR occurrence was significantly lower in the GPS 2 group (P=0.007). Successful treatment outcomes including cure and completion were also significantly lower in the GPS 2 group (P=0.001), while all-cause mortality and TB-specific mortality were higher in the GPS 2 group (P=0.001 and <0.001, respectively). Old age over than 65 years old was an independent predicting factor for high mortality and lower PR occurrence. However, the TB relapse rate was not different among the three GPS groups.

Conclusions

Higher GPS value and elderly age were identified as prognostic factors for poor outcomes in TB pleurisy and as predicting factors for lower PR occurrence. More prospective studies are needed to clarify the utility of GPS in patients with TB pleurisy.

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

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

Evaluation of Tuberculosis Treatment Response With Serial C-Reactive Protein Measurements

Background

Novel biomarkers are needed to assess response to antituberculosis therapy in smear-negative patients.

Methods

To evaluate the utility of C-reactive protein (CRP) in monitoring response to antituberculosis therapy, we conducted a post hoc analysis on a cohort of adults with symptoms of tuberculosis and negative sputum smears in a high–tuberculosis and HIV prevalence setting in KwaZulu-Natal, South Africa. Serial changes in CRP, weight, and hemoglobin were evaluated over 8 weeks.

Results

Four hundred twenty-one participants being evaluated for smear-negative tuberculosis were enrolled, and 33 were excluded. Two hundred ninety-five were treated for tuberculosis (137 confirmed, 158 possible), and 93 did not have tuberculosis. One hundred and eighty-three of 213 (86%) participants who agreed to HIV testing were HIV positive. At week 8, the on-treatment median CRP reduction in the tuberculosis group (interquartile range [IQR]) was 79.5% (25.4% to 91.7%), the median weight gain was 2.3% (−1.0% to 5.6%), and the median hemoglobin increase was 7.0% (0.8% to 18.9%); P < .0001 for baseline to week 8 comparison of absolute median values. Only CRP changed significantly at week 2 (median reduction [IQR], 75.1% [46.9% to 89.2%]) in the group with confirmed tuberculosis and in the possible tuberculosis group (median reduction [IQR], 49.0% [−0.4% to 80.9%]). Failure of CRP to reduce to ≤55% of the baseline value at week 2 predicted hospitalization or death in both tuberculosis groups, with 99% negative predictive value.

Conclusions

Change in CRP may have utility in early evaluation of response to antituberculosis treatment and to identify those at increased risk of adverse outcomes.

A Beneficial Effect of Low-Dose Aspirin in a Murine Model of Active Tuberculosis

An excessive, non-productive host-immune response is detrimental in active, chronic tuberculosis (TB) disease as it typically leads to tissue damage. Given their anti-inflammatory effect, non-steroidal anti-inflammatory drugs can potentially attenuate excessive inflammation in active TB disease. As such, we investigated the prophylactic and therapeutic effect of low-dose aspirin (LDA) (3 mg/kg/day), either alone or in combination with common anti-TB treatment or BCG vaccination, on disease outcome in an experimental murine model of active TB. Survival rate, bacillary load (BL) in lungs, and lung pathology were measured. The possible mechanism of action of LDA on the host's immune response was also evaluated by measuring levels of CD5L/AIM, selected cytokines/chemokines and other inflammatory markers in serum and lung tissue. LDA increased survival, had anti-inflammatory effects, reduced lung pathology, and decreased bacillary load in late-stage TB disease. Moreover, in combination with common anti-TB treatment, LDA enhanced survival and reduced lung pathology. Results from the immunological studies suggest the anti-inflammatory action of LDA at both a local and a systemic level. Our results showed a systemic decrease in neutrophilic recruitment, decreased levels of acute-phase reaction cytokines (IL-6, IL-1β, and TNF-α) at late stage and a delay in the decrease in T cell response (in terms of IFN-γ, IL-2, and IL-10 serum levels) that occurs during the course of Mycobacterium tuberculosis infection. An anti-inflammatory milieu was detected in the lung, with less neutrophil recruitment and lower levels of tissue factor. In conclusion, LDA may be beneficial as an adjunct to standard anti-TB treatment in the later stage of active TB by reducing excess, non-productive inflammation, while enhancing Th1-cell responses for elimination of the bacilli.

Factors associated with sputum culture conversion in patients with pulmonary tuberculosis

OBJECTIVE

The aim of this study was to determine what factors are associated with sputum culture conversion after 1 month of tuberculosis (TB) treatment.

MATERIALS AND METHODS

A total of 52 patients with new drug susceptible pulmonary TB were included in the study. Patients completed St. George respiratory questionnaire (SGRQ), they were asked about smoking, alcohol use, living conditions and education. Body mass index (BMI) measurements, laboratory tests (C reactive protein [CRP], vitamin D, albumin) were performed, and chest X-ray was done. After 1 month of treatment sputum culture was repeated.

RESULTS

Culture conversion after 1 month of treatment was found in 38.5% cases. None of investigated social factors appeared to have an effect on conversion, but worse overall health status (as reported in SGRQ) and longer duration of tobacco smoking were detected in the "no conversion" group. Concentrations of albumin, CRP, X-ray score and the time it took Mycobacterium tuberculosis culture to grow also differed. Patients who scored 30 or more on SGRQ were more than 7 times as likely to have no conversion. However, the most important factor predicting sputum culture conversion was sputum smear grade at the beginning of treatment: patients with grade of 2+ or more had more than 20-fold higher relative risk for no conversion. Using receiver operating characteristic curve analysis, we also developed a risk score for no conversion.

CONCLUSIONS

The most important factors in predicting sputum culture conversion after 1 month of treatment were grades of acid-fast bacilli in sputum smears at time of diagnosis and scores of SGRQ.

Country of residence is associated with distinct inflammatory biomarker signatures in HIV-infected patients

BACKGROUND

Inflammation and coagulation biomarkers are independent predictors of morbidity and mortality in HIV-infected patients. The impact of country of residence on these biomarkers is unknown and was investigated in persons at similar stages of HIV infection.

METHODS

Cryopreserved plasma specimens were analysed from 267 ART-naive patients with CD4 cell counts <100 cells/μl from Mexico (n=124) and South Africa (n=143). Biomarkers were compared and dimension reduction analyses were performed to highlight biosignatures according to nationality, gender and tuberculosis co-infection.

RESULTS

Mexican patients were significantly different from South Africans with regard to age, gender, CD4 cell count, haemoglobin, presence of AIDS-defining illness and prevalence of active tuberculosis. After adjusting for baseline characteristics, patients from Mexico had higher levels of IFN-γ, IL-8, and CXCL-10 whereas patients from South Africa had higher levels of fibrinogen, LTB4, P-selectin, protein S, and sCD40 ligand. The effect of country on the profile of biomarker expression was stronger than gender differences and tuberculosis co-infection.

CONCLUSION

Inflammation and coagulation biomarkers vary significantly by country. Further studies are needed to evaluate how these differences may contribute to HIV pathogenesis and prognosis in diverse populations and how they can be accounted for in studies using biomarkers as surrogate end points.