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Background: Tuberculosis (TB) causes 1.45 million deaths annually world wide, the majority of which occur in the developing world. Active TB disease represents immune failure to control latent infection from airborne spread. Acid-fast bacillus (AFB) seen on sputum smear is a biomarker for contagiousness., Methods: We enrolled 73 tuberculosis patients with extensive infiltrates into a research study using bronchoalveolar lavage (BAL) to sample lung immune cells and assay BAL cell cytokine production. All patients had sputum culture demonstrating Mycobacterium tuberculosis and 59/73 (81%) had AFB identified by microscopy of the sputum. Compared with smear negative patients, smear positive patients at presentation had a higher proportion with smoking history, a higher proportion with temperature >38.5(0) C, higher BAL cells/ml, lower percent lymphocytes in BAL, higher IL-4 and IL-12p40 in BAL cell supernatants. There was no correlation between AFB smear and other BAL or serum cytokines. Increasing IL-4 was associated with BAL PMN and negatively associated with BAL lymphocytes. Each 10-fold increase in BAL IL-4 and IL-12p40 increased the odds of AFB smear positivity by 7.4 and 2.2-fold, respectively, in a multi-variable logistic model., Conclusion: Increasing IL-4 and IL-12p40 production by BAL cells are biomarkers for AFB in sputum of patients who present with radiographically advanced TB. They likely reflect less effective immune control of pathways for controlling TB, leading to patients with increased infectiousness.

Tuberculosis leads to immune activation and increased human immunodeficiency virus type 1 (HIV-1) replication in the lung. However, in vitro models of mycobacterial infection of human macrophages do not fully reproduce these in vivo observations, suggesting that there are additional host factors. Surfactant protein A (SP-A) is an important mediator of innate immunity in the lung. SP-A levels were assayed in the human lung by using bronchoalveolar lavage (BAL). There was a threefold reduction in SP-A levels during tuberculosis only in the radiographically involved lung segments, and the levels returned to normal after 1 month of treatment. The SP-A levels were inversely correlated with the percentage of neutrophils in BAL fluid, suggesting that low SP-A levels were associated with increased inflammation in the lung. Differentiated THP-1 macrophages were used to test the effect of decreasing SP-A levels on immune function. In the absence of infection with Mycobacterium tuberculosis, SP-A at doses ranging from 5 to 0.01 micro g/ml inhibited both interleukin-6 (IL-6) production and HIV-1 long terminal repeat (LTR) activity. In macrophages infected with M. tuberculosis, SP-A augmented both IL-6 production and HIV-1 LTR activity. To better understand the effect of SP-A, we measured expression of CAAT/enhancer binding protein beta (C/EBPbeta), a transcription factor central to the regulation of IL-6 and the HIV-1 LTR. In macrophages infected with M. tuberculosis, SP-A reduced expression of a dominant negative isoform of C/EBPbeta. These data suggest that SP-A has pleiotropic effects even at the low concentrations found in tuberculosis patients. This protein augments inflammation in the presence of infection and inhibits inflammation in uninfected macrophages, protecting uninvolved lung segments from the deleterious effects of inflammation.

Background: Tuberculosis (TB) causes 1.45 million deaths annually world wide, the majority of which occur in the developing world. Active TB disease represents immune failure to control latent infection from airborne spread. Acid-fast bacillus (AFB) seen on sputum smear is a biomarker for contagiousness. Methods: We enrolled 73 tuberculosis patients with extensive infiltrates into a research study using bronchoalveolar lavage (BAL) to sample lung immune cells and assay BAL cell cytokine production. All patients had sputum culture demonstrating Mycobacterium tuberculosis and 59/73 (81%) had AFB identified by microscopy of the sputum. Compared with smear negative patients, smear positive patients at presentation had a higher proportion with smoking history, a higher proportion with temperature >38.50 C, higher BAL cells/ml, lower percent lymphocytes in BAL, higher IL-4 and IL-12p40 in BAL cell supernatants. There was no correlation between AFB smear and other BAL or serum cytokines. Increasing IL-4 was associated with BAL PMN and negatively associated with BAL lymphocytes. Each 10-fold increase in BAL IL-4 and IL-12p40 increased the odds of AFB smear positivity by 7.4 and 2.2-fold, respectively, in a multi-variable logistic model. Conclusion: Increasing IL-4 and IL-12p40 production by BAL cells are biomarkers for AFB in sputum of patients who present with radiographically advanced TB. They likely reflect less effective immune control of pathways for controlling TB, leading to patients with increased infectiousness. [ABSTRACT FROM AUTHOR]

Background: Current treatment regimens for pulmonary tuberculosis require at least 6 months of therapy. Immune adjuvant therapy with recombinant interferon-γ1b (rIFN-γb) may reduce pulmonary inflammation and reduce the period of infectivity by promoting earlier sputum clearance. Methodology/Principal Findings: We performed a randomized, controlled clinical trial of directly observed therapy (DOTS) versus DOTS supplemented with nebulized or subcutaneously administered rIFN-γ1b over 4 months to 89 patients with cavitary pulmonary tuberculosis. Bronchoalveolar lavage (BAL) and blood were sampled at 0 and 4 months. There was a significant decline in levels of inflammatory cytokines IL-1β, IL-6, IL-8, and IL-10 in 24-hour BAL supernatants only in the nebulized rIFN-c1b group from baseline to week 16. Both rIFN-γ1b groups showed significant 3-fold increases in CD4+ lymphocyte response to PPD at 4 weeks. There was a significant (p = 0.03) difference in the rate of clearance of Mtb from the sputum smear at 4 weeks for the nebulized rIFN-γ1b adjuvant group compared to DOTS or DOTS with subcutaneous rIFNγ1b. In addition, there was significant reduction in the prevalence of fever, wheeze, and night sweats at 4 weeks among patients receiving rFN-γ1b versus DOTS alone. Conclusion: Recombinant interferon-γ1b adjuvant therapy plus DOTS in cavitary pulmonary tuberculosis can reduce inflammatory cytokines at the site of disease, improve clearance of Mtb from the sputum, and improve constitutional symptoms. Trial Registration: ClinicalTrials.gov NCT00201123. [ABSTRACT FROM AUTHOR]

Summary: The host response to Mycobacterium tuberculosis includes macrophage activation, inflammation with increased immune effector cells, tissue necrosis, and cavity formation, and fibrosis, distortion, and bronchiectasis. To evaluate the molecular basis of the immune response in the lungs of patients with active pulmonary tuberculosis (TB), we used bronchoalveolar lavage to obtain cells at the site of infection. Affymetrix GeneChip microarrays and cDNA nylon filter microarrays interrogated gene expression in bronchoalveolar lavage (BAL) cells from 11 healthy controls and 17 patients with active pulmonary TB. We found altered gene expression for 69 genes in TB versus normal controls that included cell surface markers, cytokines, chemokines, receptors, transcription factors, and complement components. In addition, TB BAL cell gene expression patterns segregated into 2 groups: one suggestive of a T helper type 1 (Th1) cellular immune response with increased signal transducer and activator of transcription-4 (STAT-4), interferon-gamma (IFN-γ receptor), and monokine induced by IFN-γ (MIG) expression with increased IFN-γ protein levels in BAL fluid; the other group displayed characteristics of Th2 immunity with increased STAT-6, CD81, and IL-10 receptor expression. We were able to demonstrate that a Th2 presentation could change to a Th1 pattern after anti-tuberculous treatment in 1 TB patient studied serially. These gene expression data support the conclusion that pulmonary TB produces a global change in the BAL cell transcriptome with manifestations of either Th1 or Th2 immunity. [Copyright &y& Elsevier]

Summary: Pulmonary tuberculosis may alter volatile organic compounds (VOCs) in breath because Mycobacteria and oxidative stress resulting from Mycobacterial infection both generate distinctive VOCs. The objective of this study was to determine if breath VOCs contain biomarkers of active pulmonary tuberculosis. Head space VOCs from cultured Mycobacterium tuberculosis were captured on sorbent traps and assayed by gas chromatography/mass spectroscopy (GC/MS). One hundred and thirty different VOCs were consistently detected. The most abundant were naphthalene, 1-methyl-, 3-heptanone, methylcyclododecane, heptane, 2,2,4,6,6-pentamethyl-, benzene, 1-methyl-4-(1-methylethyl)-, and cyclohexane, 1,4-dimethyl-. Breath VOCs were assayed by GC/MS in 42 patients hospitalized for suspicion of pulmonary tuberculosis and in 59 healthy controls. Sputum cultures were positive for Mycobacteria in 23/42 and negative in19/42 patients. Breath markers of oxidative stress were increased in all hospitalized patients . Pattern recognition analysis and fuzzy logic analysis of breath VOCs independently distinguished healthy controls from hospitalized patients with 100% sensitivity and 100% specificity. Fuzzy logic analysis identified patients with positive sputum cultures with 100% sensitivity and 100% specificity (95.7% sensitivity and 78.9% specificity on leave-one-out cross-validation); breath VOC markers were similar to those observed in vitro, including naphthalene, 1-methyl- and cyclohexane, 1,4-dimethyl-. Pattern recognition analysis identified patients with positive sputum cultures with 82.6% sensitivity (19/23) and 100% specificity (18/18), employing 12 principal components from 134 breath VOCs. We conclude that volatile biomarkers in breath were sensitive and specific for pulmonary tuberculosis: the breath test distinguished between “sick versus well” i.e. between normal controls and patients hospitalized for suspicion of pulmonary tuberculosis, and between infected versus non-infected patients i.e. between those whose sputum cultures were positive or negative for Mycobacteria. [Copyright &y& Elsevier]

Study objectives: Aerosol interferon-γ (IFN-γ) is a potential immunomodulator in the treatment of pulmonary tuberculosis (TB). Previous investigations demonstrated conversion of sputum smears in five patients with multidrug-resistant TB after 12 treatments over 1 month, and induction of signaling molecules in 10 of 11 drug-sensitive TB patients using BAL. The objective of the current study was to evaluate particle size and deposition pattern in patients with TB receiving aerosol IFN-γ treatment. Design: Particle size was determined with a cascade impactor, and deposition of IFN-γ mixed with 99mTc-labeled human serum albumin was assessed using a gamma camera. Local levels of IFN-γ were measured in BAL using enzyme-linked immunosorbent assays. Study patients/intervention: Fourteen patients with pulmonary TB received IFN-γ aerosol (500 µg) for 12 treatments in addition to antimycobacterial therapy with BAL before and after IFN-γ aerosol treatment. Eight patients with minimal-to-moderate parenchymal involvement underwent deposition studies. Deposited 99mTc-labeled IFN-γ aerosol was partitioned between upper airways and lungs using attenuation correction measurements. 133Xe equilibrium scanning, 133Xe washout, and 99mTc- macroaggregate injection defined regional lung volume, ventilation, and perfusion. Results: Upper airway deposition was significant often exceeding lung deposition (53.9 ± 7.09 µg vs 35.8 _ 2.73 µg, respectively [mean ± SE]). IFN-γ levels measured in BAL fluid were significantly increased with aerosol treatment (0.83 ± 0.43 µg before vs 24.76 ± 8.71 µg after, p < 0.017), and IFN-γ levels correlated with regional deposition of IFN-γ aerosol (r = 0.823). Four-quadrant analysis of regional lung deposition best correlated with regional perfusion (r = 0.422, p = 0.013) with penetration of aerosol into areas of obvious radiographic infiltration on chest radiograph. Conclusions: Aerosol therapy with IFN-γ in patients with pulmonary TB is widely distributed and results in significant enhancement of IFN-γ levels in the lower respiratory tract. In patients without lung destruction, IFN-γ aerosol may be an adjuvant to enhance the local immune response. [ABSTRACT FROM AUTHOR]

Study objectives: To investigate the characteristics of tuberculosis infection in diabetic patients at Bellevue Hospital. Design: We conducted a case-control study retrospectively reviewing the records of patients at Bellevue Hospital Center from 1987 to 1997 with a discharge diagnosis of tuberculosis and diabetes mellitus. Setting: Bellevue Hospital Center is a 1,200-bed, inner-city municipal hospital located in the Lower East Side of New York City. Patients: Fifty-three identified patients had verified tuberculosis infection and diabetes; of these, 50 charts were available for review. One hundred five control cases were selected from nondiabetic patients with a discharge diagnosis of tuberculosis during the same time period. Measurements and results: Thirty-six percent (18 cases) of the patients with diabetes and tuberculosis had multidrug-resistant tuberculosis (MDR-TB) compared to only 10% (10 cases) in the control group (p < 0.01) Controlling for homelessness, HIV status, and directly observed therapy, the relative risk of MDR-TB was calculated to be 8.6 (confidence interval, 3.1 to 23.6) in the diabetic group compared to the control group. Conclusions: There was a significant association between diabetes and MDR-TB. Diabetes continues to be a risk factor for tuberculosis and was associated with MDR-TB in our patients. [ABSTRACT FROM AUTHOR]

Abstract: Quality assurance (QA) is essential for data accuracy and proper evaluation of study objectives in clinical trials. The Tuberculosis Trials Consortium (TBTC)–a collaboration of 28 clinical sites and the Centers for Disease Control and Prevention–has developed a comprehensive QA program that provides quantitative assessments of performance based on clearly defined standards that are communicated to data collectors through a feedback process. The Implementation and Quality Committee of the TBTC developed a Site Evaluation Report (SER) that assesses performance measures (PMs) critical to the accomplishment of study objectives. PMs are defined, quantified, and evaluated, and goals and minimum acceptable scores are specified. Sites not meeting a PM minimum must provide an explanation and develop a plan to meet the goal. Site-specific and system-wide problems can be readily identified through this process. The SER is used prospectively for all TBTC treatment trials, and a Web site has been developed to maximize the availability and usefulness of performance data. The TBTC''s comprehensive QA program is an example of a successful method for ensuring high quality, evaluable data. [Copyright &y& Elsevier]