Tuberculosis associated with Triplet therapy for lung cancer.

We report the first case of TB associated with triplet therapy (chemotherapy and immunotherapy concurrently) for lung cancer, developing just 44 days after treatment initiation. We feel that several important learning points arise from the discussion that are likely to be very relevant to the broad readership of Thorax, and have important clinical and scientific implications. In the three discussion paragraphs, we highlight that: 1) Triplet therapy is now standard first-line treatment for inoperable lung cancer. 2) TB reactivation is increasingly recognised as an adverse effect of immune checkpoint inhibition, but sending diagnostic samples is critical to avoid a missed diagnosis. 3) These insights from novel cancer immunotherapies are challenging the traditional views of the host-pathogen interaction in TB, with wide implications for future control strategies. We propose that the cases reported in the literature are likely to be the tip of the iceberg as most people with lung cancer managed with antiprogrammed death-1 agents who develop new lung lesions will be treated with standard antibiotics and then palliated when they do not respond.

Variation in C - reactive protein response according to host and mycobacterial characteristics in active tuberculosis.

BACKGROUND: The C - reactive protein (CRP) response is often measured in patients with active tuberculosis (TB) yet little is known about its relationship to clinical features in TB, or whether responses differ between ethnic groups or with different Mycobacterium tuberculosis (M.tb) strain types. We report the relationship between baseline serum CRP prior to treatment and disease characteristics in a metropolitan population with TB resident in a low TB incidence region. METHODS: People treated for TB at four London, UK sites between 2003 and 2014 were assessed and data collected on the following characteristics: baseline CRP level; demographics (ethnicity, gender and age); HIV status; site of TB disease; sputum smear (in pulmonary cases) and culture results. The effect of TB strain-type was also assessed in culture-positive pulmonary cases using VNTR typing data. RESULTS: Three thousands two hundred twenty-two patients were included in the analysis of which 72 % had a baseline CRP at or within 4 weeks prior to starting TB treatment. CRP results were significantly higher in culture positive cases compared to culture negative cases: median 49 mg/L (16-103 mg/L) vs 19 mg/L (IQR 5-72 mg/L), p = <0.001. In those with pulmonary disease, smear positive cases had a higher CRP than smear negative cases: 67 mg/L (31-122 mg/L) vs 24 mg/L (7-72 mg/L), p < 0.001. HIV positive cases had higher baseline CRPs than HIV negative cases: 75 mg/L (26-136 mg/L) vs 37 mg/L (10-88 mg/L), p <0.001. Differing sites of disease were associated with differences in baseline CRP: locations that might be expected to have a high mycobacterial load (e.g. pulmonary disease and disseminated disease) had a significantly higher CRP than those such as skin, lymph node or CNS disease, where the mycobacterial load is typically low in HIV negative subjects. In a multivariable log-scale linear regression model adjusting for host characteristics and M.tb strain type, infection with the East African Indian strain was associated with significantly lower baseline-CRP (fold-change in CRP 0.51 (0.34-0.77), p < 0.01). CONCLUSIONS: Host and mycobacterial factors are strongly associated with baseline CRP response in tuberculosis. This analysis suggests that there are important differences in innate immune response according to ethnicity, Mtb strain type and site of disease. This may reflect differing mycobacterial loads or host immune responses.

Determinants of treatment-related paradoxical reactions during anti-tuberculosis therapy: a case control study.

BACKGROUND: Inflammatory response following initial improvement with anti-tuberculosis (TB) treatment has been termed a paradoxical reaction (PR). HIV co-infection is a recognised risk, yet little is known about other predictors of PR, although some biochemical markers have appeared predictive. We report our findings in an ethnically diverse population of HIV-infected and uninfected adults. METHODS: Prospective and retrospective clinical and laboratory data were collected on TB patients seen between January 1999-December 2008 at four UK centres selected to represent a wide ethnic and socio-economic mix of TB patients. Data on ethnicity and HIV status were obtained for all individuals. The associations between other potential risk factors and PR were assessed in a nested case-control study. All PR cases were matched two-to-one to controls by calendar time and centre. RESULTS: Of 1817 TB patients, 82 (4.5 %, 95 % CI 3.6-5.5 %) were identified as having a PR event. The frequency of PR was 14.4 % (18/125; 95 % CI 8.2-20.6 %) and 3.8 % (64/1692; 2.9-4.7) for HIV-positive and HIV-negative individuals respectively. There were no differences observed in PR frequency according to ethnicity, although the site was more likely to be pulmonary in those of black and white ethnicity, and lymph node disease in those of Asian ethnicity. In multivariate analysis of the case-control cohort, HIV-positive patients had five times the odds of developing PR (aOR = 5.05; 95 % CI 1.28-19.85, p = 0.028), whilst other immunosuppression e.g. diabetes, significantly reduced the odds of PR (aOR = 0.01; 0.00-0.27, p = 0.002). Patients with positive TB culture had higher odds of developing PR (aOR = 6.87; 1.31-36.04, p = 0.045) compared to those with a negative culture or those in whom no material was sent for culture. Peripheral lymph node disease increased the odds of a PR over 60-fold 4(9.60-431.25, p < 0.001). CONCLUSION: HIV was strongly associated with PR. The increased potential for PR in people with culture positive TB suggests that host mycobacterial burden might be relevant. The increased risk with TB lymphadenitis may in part arise from the visibility of clinical signs at this site. Non-HIV immunosuppression may have a protective effect. This study highlights the difficulties in predicting PR using routinely available demographic details, clinical symptoms or biochemical markers.

HIV-1 infection of macrophages dysregulates innate immune responses to Mycobacterium tuberculosis by inhibition of interleukin-10.

Human immunodeficiency virus (HIV)-1 and Mycobacterium tuberculosis (M. tuberculosis) both target macrophages, which are key cells in inflammatory responses and their resolution. Therefore, we tested the hypothesis that HIV-1 may modulate macrophage responses to coinfection with M. tuberculosis. HIV-1 caused exaggerated proinflammatory responses to M. tuberculosis that supported enhanced virus replication, and were associated with deficient stimulus-specific induction of anti-inflammatory interleukin (IL)-10 and attenuation of mitogen-activated kinase signaling downstream of Toll-like receptor 2 and dectin-1 stimulation. Our in vitro data were mirrored by lower IL-10 and higher proinflammatory IL-1ß in airway samples from HIV-1-infected patients with pulmonary tuberculosis compared with those with non-tuberculous respiratory tract infections. Single-round infection of macrophages with HIV-1 was sufficient to attenuate IL-10 responses, and antiretroviral treatment of replicative virus did not affect this phenotype. We propose that deficient homeostatic IL-10 responses may contribute to the immunopathogenesis of active tuberculosis and propagation of virus infection in HIV-1/M. tuberculosis coinfection.

Diagnosis and subtyping of de novo and relapsed mediastinal lymphomas by endobronchial ultrasound needle aspiration.

RATIONALE: The current management of lymphoma requires accurate diagnosis and subtyping of de novo lymphoma and of relapsed or refractory lymphoma in known cases. The role of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the clinical management of lymphomas is unclear. OBJECTIVES: To investigate the use of EBUS-TBNA in the diagnosis of de novo and relapsed mediastinal lymphomas. METHODS: A total of 2,256 consecutive patients who underwent EBUS-TBNA in a tertiary center between February 2008 and April 2013 were prospectively evaluated. The diagnostic accuracy and clinical use of EBUS-TBNA in 100 cases of de novo or suspected relapsed mediastinal lymphoma was investigated by comparing EBUS-TBNA diagnosis with the final diagnosis. MEASUREMENTS AND MAIN RESULTS: De novo mediastinal lymphoma was correctly diagnosed by EBUS-TBNA in 45 (88%) of 51 and relapsed lymphoma in 15 (100%) of 15 lymphoma cases. EBUS-TBNA accurately established a diagnosis other than lymphoma in 32 (97%) of 33 patients with suspected lymphoma relapse. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EBUS-TBNA in the diagnosis of mediastinal lymphoma were 89%, 97%, 98%, 83%, and 91%, respectively. Sensitivity of EBUS-TBNA in subtyping lymphomas into high-grade non-Hodgkin lymphoma, low-grade non-Hodgkin lymphoma, and Hodgkin lymphoma was 90%, 100%, and 79%, respectively. EBUS-TBNA diagnosis was adequate for clinical management in 84 (84%) of 100 cases. CONCLUSIONS: Multimodality evaluation of EBUS-TBNA can be successful in the diagnosis of de novo mediastinal lymphomas and is ideally suited in distinguishing lymphoma relapse from alternative pathologies; it is least sensitive in subtyping Hodgkin lymphoma.

Non-tuberculous mycobacterial pulmonary disease (NTM-PD): Epidemiology, diagnosis and multidisciplinary management.

Non-tuberculous mycobacteria (NTM) are ubiquitous environmental organisms that can cause significant disease in both immunocompromised and immunocompetent individuals. The incidence of NTM pulmonary disease (NTM-PD) is rising globally. Diagnostic challenges persist and treatment efficacy is variable. This article provides an overview of NTM-PD for clinicians. We discuss how common it is, who is at risk, how it is diagnosed and the multidisciplinary approach to its clinical management.

Lung infections in the HIV-infected adult.

PURPOSE OF REVIEW: This review describes current epidemiology, diagnosis, treatment and prevention of adult HIV-related lung infections using evidence published within the past 2 years. RECENT FINDINGS: Recent evidence has helped better determine the importance of early initiation of antiretroviral therapy in co-infected individuals with advanced immune suppression. Although this has led to a greatly reduced incidence of opportunistic infections in people with HIV, Pneumocystis pneumonia remains common. Pneumonia due to bacterial pathogens, such as Streptococcus pneumoniae, also causes considerable disease burden, but emerging evidence of the clinical efficacy of pneumococcal vaccination, especially conjugated vaccines, offers considerable promise. As HIV-infected populations become older, more emphasis should be given to the potential benefit of influenza prevention, particularly with vaccination, and encouraging smoking cessation. Co-infection with tuberculosis is still a huge problem worldwide, but the recent development and use of simple clinical algorithms based on symptoms and point-of-care testing for recognizing active disease offers great potential. SUMMARY: The lung remains an important site of disease in HIV-infected individuals. Increasing emphasis should be placed upon prevention of infection and modification of risk factors.

Utility of endobronchial ultrasound-guided transbronchial needle aspiration in patients with tuberculous intrathoracic lymphadenopathy: a multicentre study.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has emerged as an important tool for the diagnosis and staging of lung cancer but its role in the diagnosis of tuberculous intrathoracic lymphadenopathy has not been established. The aim of this study was to describe the diagnostic utility of EBUS-TBNA in patients with intrathoracic lymphadenopathy due to tuberculosis (TB). METHODS: 156 consecutive patients with isolated intrathoracic TB lymphadenitis were studied across four centres over a 2-year period. Only patients with a confirmed diagnosis or unequivocal clinical and radiological response to antituberculous treatment during follow-up for a minimum of 6 months were included. All patients underwent routine clinical assessment and a CT scan prior to EBUS-TBNA. Demographic data, HIV status, pathological findings and microbiological results were recorded. RESULTS: EBUS-TBNA was diagnostic of TB in 146 patients (94%; 95% CI 88% to 97%). Pathological findings were consistent with TB in 134 patients (86%). Microbiological investigations yielded a positive culture of TB in 74 patients (47%) with a median time to positive culture of 16 days (range 3-84) and identified eight drug-resistant cases (5%). Ten patients (6%) did not have a specific diagnosis following EBUS; four underwent mediastinoscopy which confirmed the diagnosis of TB while six responded to empirical antituberculous therapy. There was one complication requiring an inpatient admission. CONCLUSIONS: EBUS-TBNA is a safe and effective first-line investigation in patients with tuberculous intrathoracic lymphadenopathy.

Validation of Differentially Expressed Immune Biomarkers in Latent and Active Tuberculosis by Real-Time PCR.

Tuberculosis (TB) remains a major global threat and diagnosis of active TB ((ATB) both extra-pulmonary (EPTB), pulmonary (PTB)) and latent TB (LTBI) infection remains challenging, particularly in high-burden countries which still rely heavily on conventional methods. Although molecular diagnostic methods are available, e.g., Cepheid GeneXpert, they are not universally available in all high TB burden countries. There is intense focus on immune biomarkers for use in TB diagnosis, which could provide alternative low-cost, rapid diagnostic solutions. In our previous gene expression studies, we identified peripheral blood leukocyte (PBL) mRNA biomarkers in a non-human primate TB aerosol-challenge model. Here, we describe a study to further validate select mRNA biomarkers from this prior study in new cohorts of patients and controls, as a prerequisite for further development. Whole blood mRNA was purified from ATB patients recruited in the UK and India, LTBI and two groups of controls from the UK (i) a low TB incidence region (CNTRLA) and (ii) individuals variably-domiciled in the UK and Asia ((CNTRLB), the latter TB high incidence regions). Seventy-two mRNA biomarker gene targets were analyzed by qPCR using the Roche Lightcycler 480 qPCR platform and data analyzed using GeneSpring™ 14.9 bioinformatics software. Differential expression of fifty-three biomarkers was confirmed between MTB infected, LTBI groups and controls, seventeen of which were significant using analysis of variance (ANOVA): CALCOCO2, CD52, GBP1, GBP2, GBP5, HLA-B, IFIT3, IFITM3, IRF1, LOC400759 (GBP1P1), NCF1C, PF4V1, SAMD9L, S100A11, TAF10, TAPBP, and TRIM25. These were analyzed using receiver operating characteristic (ROC) curve analysis. Single biomarkers and biomarker combinations were further assessed using simple arithmetic algorithms. Minimal combination biomarker panels were delineated for primary diagnosis of ATB (both PTB and EPTB), LTBI and identifying LTBI individuals at high risk of progression which showed good performance characteristics. These were assessed for suitability for progression against the standards for new TB diagnostic tests delineated in the published World Health Organization (WHO) technology product profiles (TPPs).

Detection of mycobacterial antigen responses in lung but not blood in HIV-tuberculosis co-infected subjects.

Forty-seven HIV-infected adults had broncho-alveolar lavage stimulated with purified protein derivate of Mycobacterium tuberculosis. Eighteen of 19 (95%) with tuberculosis co-infection had interferon-gamma synthetic CD4 lymphocyte responses > 1% versus three of 28 (11%) without (P < 0.0001). Lung response was unrelated to blood CD4 cell count. BAL HIV tuberculosis responses were similar in 25 HIV-uninfected tuberculosis patients. Responses in matched blood samples were often undetectable. Therefore, immunological tuberculosis assays seem less affected by HIV co-infection when lung-based.

Tuberculosis and HIV co-infection: a practical therapeutic approach.

HIV and tuberculosis (TB) are leading global causes of mortality and morbidity, and yet effective treatment exists for both conditions. Rifamycin-based antituberculosis therapy can cure HIV-related TB and, where available, the introduction of highly active antiretroviral therapy (HAART) has markedly reduced the incidence of AIDS and death. Optimal treatment regimens for HIV/TB co-infection are not yet clearly defined. Combinations are limited by alterations in the activity of the hepatic cytochrome P450 (CYP) enzyme system, which in particular may produce subtherapeutic plasma concentrations of antiretroviral drugs. For example, protease inhibitors often must be avoided if the potent CYP inducer rifampicin is co-administered. However, an alternative rifamycin, rifabutin, which has similar efficacy to rifampicin, can be used with appropriate dose reduction. Available clinical data suggest that, for the majority of individuals, rifampicin-based regimens can be successfully combined with the non-nucleoside reverse transcriptase inhibitors nevirapine and efavirenz. Most available HAART regimens in areas that have a high burden of TB contain one or the other of these drugs as a backbone. However, significant questions remain as to the optimal dose of either agent required to ensure therapeutic plasma concentrations, especially in relation to particular ethnic groups. The timing of HAART initiation after starting antituberculosis therapy continues to be controversial. Debate centres upon whether early initiation of HAART increases the risk of paradoxical reactions (immune reconstitution-related events) and other adverse events, or whether delay greatly elevates the risk of disease progression. Further prospective clinical data are needed to help inform practice in this area.

The Transcriptional Signature of Active Tuberculosis Reflects Symptom Status in Extra-Pulmonary and Pulmonary Tuberculosis.

BACKGROUND: Mycobacterium tuberculosis infection is a leading cause of infectious death worldwide. Gene-expression microarray studies profiling the blood transcriptional response of tuberculosis (TB) patients have been undertaken in order to better understand the host immune response as well as to identify potential biomarkers of disease. To date most of these studies have focused on pulmonary TB patients with gene-expression profiles of extra-pulmonary TB patients yet to be compared to those of patients with pulmonary TB or sarcoidosis. METHODS: A novel cohort of patients with extra-pulmonary TB and sarcoidosis was recruited and the transcriptional response of these patients compared to those with pulmonary TB using a variety of transcriptomic approaches including testing a previously defined 380 gene meta-signature of active TB. RESULTS: The 380 meta-signature broadly differentiated active TB from healthy controls in this new dataset consisting of pulmonary and extra-pulmonary TB. The top 15 genes from this meta-signature had a lower sensitivity for differentiating extra-pulmonary TB from healthy controls as compared to pulmonary TB. We found the blood transcriptional responses in pulmonary and extra-pulmonary TB to be heterogeneous and to reflect the extent of symptoms of disease. CONCLUSIONS: The transcriptional signature in extra-pulmonary TB demonstrated heterogeneity of gene expression reflective of symptom status, while the signature of pulmonary TB was distinct, based on a higher proportion of symptomatic individuals. These findings are of importance for the rational design and implementation of mRNA based TB diagnostics.

Does immune reconstitution syndrome promote active tuberculosis in patients receiving highly active antiretroviral therapy?

OBJECTIVES: To assess whether highly active anti-retroviral therapy (HAART) contributes to the presentation of active tuberculosis (TB). DESIGN: Retrospective single-centre cohort study. METHODS: A total of 111 HIV-infected individuals with active TB were identified at an urban teaching hospital between February 1997 and April 2004. Those receiving HAART at the time of TB diagnosis were assessed. RESULTS: Nineteen of 111 (17%) were receiving HAART when TB developed. Within this group there appeared to be two distinct populations. Thirteen of 19, 12 from ethnic or social groups with high background rates of TB, developed disease a median of 41 days (range, 7-109) after starting HAART ('early TB' group). In six of 19 ('late TB' group), TB occurred a median of 358 days after HAART initiation (range, 258-598). The 'early TB' group had lower CD4 cell counts when starting HAART in comparison with the 'late TB' group (median; 87 versus 218 x 10 cells/l; P = 0.04); however no difference was observed in the rate of change of CD4 cell count (P = 0.5) or HIV load. Paradoxical reaction rate in the 'early TB' group was significantly greater than in the 'late-TB' group (62 versus 0%, P = 0.02) and greater than in a similar control population who started HAART while taking anti-TB therapy (62 versus 30%, P = 0.05). CONCLUSIONS: These data suggest anti-HIV treatment may amplify the presentation of active TB. This has implications for antiretroviral programmes in countries with high TB rates and warrants prospective investigation of a larger cohort.

Expression of a novel cytokine, IL-4delta2, in HIV and HIV-tuberculosis co-infection.

BACKGROUND: Correcting the Th2 shift in HIV/AIDS represents a potential intervention strategy. However data on interleukin (IL)-4 expression in HIV or AIDS are un-interpretable because of failure to distinguish between IL-4 and its splice variant and natural antagonist, IL-4delta2. OBJECTIVE: To determine Th1 [interferon (IFN)-gamma], IL-4delta2 and Th2 (IL-4) expression in whole blood and lung lavage from healthy volunteers and in HIV or HIV-tuberculosis (TB) co-infection. DESIGN: Cross-sectional with prospective cohort. METHODS: Expression of IL-4delta2, IL-4 and IFN-gamma were determined by quantitative real-time PCR, using unstimulated cells from whole blood and lung lavage, in 20 HIV-TB (pulmonary) co-infected patients, 20 matched HIV-positive controls and 20 HIV-negative healthy volunteers. Results were correlated with plasma viral load, CD4 cell counts, radiological scores and response to anti-TB treatment. RESULTS: Compared to HIV negative donors, stable HIV-positive donors did not have increased levels of mRNA encoding IL-4, IL-4delta2 or IFN-gamma in blood or lavage. By contrast, the HIV-TB co-infected donors had increased IL-4 and IFN-gamma in both compartments. However the antagonist, IL-4delta2 was increased only in lavage. Consequently the dominant form was IL-4delta2 in lavage, but IL-4 itself in blood. The lung IL-4/IFN-gamma ratio correlated with radiological disease extent. With anti-TB treatment, IL-4 levels did not change whilst IL-4delta2 levels increased significantly. CONCLUSIONS: IL-4 and its natural antagonist, IL-4delta2 and are not upregulated in the absence of opportunistic infection. However in HIV-TB co-infection both cytokines increase in lung, but only IL-4 in the periphery. Further studies are required to determine if IL-4 facilitates systemic HIV progression.

Paradoxical reactions and immune reconstitution inflammatory syndrome in tuberculosis.

The coalescence of the HIV-1 and tuberculosis (TB) epidemics in Sub-Saharan Africa has had a significant and negative impact on global health. The availability of effective antimicrobial treatment for both HIV-1 (in the form of highly active antiretroviral therapy (HAART)) and TB (with antimycobacterial agents) has the potential to mitigate the associated morbidity and mortality. However, the use of both HAART and antimycobacterial therapy is associated with the development of inflammatory paradoxical syndromes after commencement of therapy. These include paradoxical reactions (PR) and immune reconstitution inflammatory syndromes (IRIS), conditions that complicate mycobacterial disease in HIV seronegative and seropositive individuals. Here, we discuss case definitions for PR and IRIS, and explore how advances in identifying the risk factors and immunopathogenesis of these conditions informs our understanding of their shared underlying pathogenesis. We propose that both PR and IRIS are characterized by the triggering of exaggerated inflammation in a setting of immunocompromise and antigen loading, via the reversal of immunosuppression by HAART and/or antimycobacterials. Further understanding of the molecular basis of this pathogenesis may pave the way for effective immunotherapies for the treatment of PR and IRIS.