Dysregulated Production of IFN-g, IL-12, and IL-10 by Peripheral Blood Mononuclear Cells from Early Active Pulmonary and Multidrug-Resistant Tuberculosis Patients

In this study, we investigated profiles of the cytokines IFN-g, IL-12, and IL-10 in active pulmonary tuberculosis (EAPTB) patients, HIV-negative patients with multidrug-resistant tuberculosis (MDR-TB) and in healthy tuberculin reactors (HTR). We studied the responses of peripheral blood mononuclear cells (PBMC) from 12 EAPTB patients and 15 MDR-TB patients to stimulation with a purified protein derivatives (PPD) antigen (Ag), and compared them with those from 14 HTR. Using ELISA, IFN-g production was found to be significantly depressed, while IL-10 was significantly elevated in both MDR-TB and EAPTB after in vitro stimulation with PPD, compared with those in HTR. Although there was no significant difference in IL-12 production among the three groups, mean IL-12 production was highest in patients with MDR-TB. In these patients, IL-12 production was significantly correlated with IL-10 expression, but not IFN-g production. In addition, neutralization of endogenous IL-10 led to enhanced IFN-g and IL-12Rb2 mRNA expression in TB patients. Our findings suggest that both groups of TB patients may have a similar disregulated pattern of IL-12, IL-10, and IFN-g production during M. tuberculosis infection. Furthermore, the results suggest a potentially pathogenic role for IL-10 in impaired Th1 immune responses in TB patients.

Depression of Both Interferon-gamma and Tumor Necrosis Factor-alpha Production by Peripheral Blood Mononuclear Cells from Chronic Refractory Tuberculosis Patients

Understanding human immune responses in chronic refractory tuberculosis (CRTB) is important for developing immunotherapy against the disease. The aim of this study was to examine cytokine responses [interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-10] by peripheral blood mononuclear cells (PBMCs) in CRTB patients after in vitro stimulation with the 30-kDa or purified protein derivative (PPD) antigen (Ag). Most of the CRTB cases were multidrug-resistant (MDR) TB. The results were compared with those from early TB (E-TB) patients and healthy tuberculin reactors (HTR). IFN-gamma production was significantly depressed in both CRTB and E-TB groups compared with HTR. In response to the 30-kDa Ag, TNF-alpha levels were significantly depressed only in CRTB patients, while greatly increased in E-TB patients. In addition, IL-10 production was significantly increased in E-TB patients, and PBMC from both E-TB and CRTB patients secreted more IL-6 than HTR. IL-10 neutralization significantly increased TNF-alpha levels, whereas anti-TNF-alpha did not alter IL-10 induction significantly in PBMC from HTR and CRTB patients. Our findings suggest that CRTB patients have depression in both IFN-gamma and TNF-alpha reponses, which might play important roles during chronic M. tuberculosis infection.

The Analysis of Risk Factors of Pulmonary Tuberculosis Patients Failed in Retreatment / 결핵

BACKGROUND: Surgery may have a role when medical treatment alone is not successful in patients with multi-drug resistant (MDR) pulmonary tuberculosis (PTB). To document the role of resection in MDR PTB, we analyzed 4 years of our experience. METHODS: A retrospective review was performed on thirteen patients that underwent pulmonary resection for MDR PTB between May 1996 and February 2000. All patients had organisms resistant to many of the first-line drugs including isoniazid (INH) and rifampicin (RFP). RESULTS: The thirteen patients were 37.5±12.4 years old (mean±S.D.)(M:F=5:8), and their sputum was culture positive even with adequate medication for prolonged periods (109.7±132.0 months), resistant to 2-8 drugs including isoniazid and rifampin. All patients had localized lesion(s) and most (92.3%) had cavities. At least 3 sensitive anti-TB medications were started before surgery in all patients according to the drug sensitivity test. The preoperative FE1 was 2.37±0.83 L. Lobectomy was performed in 11 patients and pleuropneumonectomy in two. Postoperative mortality did not occur, but pneumonia occurred as a complication in one (7.7%). After 41.5±58.9 days (range 1~150 days) follow up, negative conversion of sputum culture was achieved in all patients within 5 months. Only one patient (7.7%) recurred 32 months after lung resection. CONCLUSION: When medical treatment alone is not successful, surgical resection can be a good treatment option in patients with localized MDR PTB.

Rapid Extraction of DNA using Ion Exchange Resin for Early Detection ofMycobacterium tuberculosis by the Polymerase Chain Reaction / 결핵

BACKGROUND: The extraction methods of DNA from clinical samples are the major obstacle to use the PCR(Polymerase Chain Reaction) in routine labortary for early detection of M. tuberculosis. We tried to improve the extraction method of DNA from sputum for establishment of the PCR in routine labortary by reducing the possibility of cross contamination and performing it easily and safely. METHODS: We used the InstaGene(TM) DNA extraction kit(BioRad Co.) using Chelex 100 ion exchange resin for preparation of DNA. We compared InstaGene method in 100 cases of sputum from proteinase K method which is known as the most commonly used method for DNA purification(Experiment 1). And we compared InstaGene method in 98 cases of sputum from Microwave method developed by a company in Korea(Experiment 2). In experiment 1, 245bps of IS6110 were amplified and then 188bps were amplified by nested PCR. In experiment 2, 536bps in primary PCR and 276bps in nested PCR were amplified and analysed by agarose gel electrophoresis and EtBr staining. RESULTS: When we chose AFB smear, culture, or AFB smear and culture as a standard test, PCR had low specificity and positive predictive value in both experiments. The InstaGene method has higher value in sensitivity and negative predictive value significantly than proteinase K method. The InstaGene method and the Microwave methods were similar in sensitivity, specificity, positive predictive value and negative predictive value.. CONCLUSION: Even though both methods had lower possibility of cross contamination, shorter time requrirement, simplicity, and economic advantages than Proteinase K method, the InstaGene method was a little simpler than the Microwave method. Therefore, in terms of usfulness in clinical application, the Instagene method seems to be the most useful method in DNA extraction for detection of M. tuberculosis using PCR. The reliability of this method will be clarified by further studies with enough clinical samples.

Clinical Evaluation of Surgical Resection of Pulmonary Tuberculosis / 결핵

BACKGROUND: In spite of initial intensive and long-term chemotherapy for pulmonary tuberculosis, many problems remain in the treatment of the residual lesion. The role of surgical intervention for pulmonary tuberculosis is getting rid of such residual lesion of pulmonary tuberculosis to support the healing process and to induce bacteriologically negative conversion in the end. METHOD: We experienced 30 cases of pulmonary resection for pulmonary tuberculosis from Aug. 1994 through Apr. 1995 in National Masan Tuberculosis Hospital. We conducted retrospective study to analyze several variables for the cases. RESULTS: 1) The ratio between male and female was 4:l(male 24, female 6) and the age of peak incidence was in 3rd and 4th decades. 2) Indications for pulmonary resection in the radiographic findings were cavitary lesions of 19 cases(63.3%), destroyed one side of 8 cases(26.7%) and destroyed one lobe of 3 cases(10%). 3) 16 of 20 cases with unilateral lesions and all of 10 cases with bilateral lesions on chest X-ray films showed AFB positive on preoperative sputum smears. 14 cases(87.5%) of unilateral lesions and 9 cases(90%) of bilateral ones were converted into AFB negative postoperatively. Negative conversion rates of pneumonectomy and lobectomy cases were 100% and 85.7%, respectively. 4) Preoperative combined disease was 3 cases(10%) of DM and postoperative complications were 2 cases(6.7%) of dead space and no death. CONCLUSION: Chemotherapy only has some limitation in treatment of all tuberculosis. So, surgical intervention for pulmonary tuberculosis is an effective method as partner of chemotherapy.