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Mycobacterium Tuberculosis Infection (mycobacterium + tuberculosis_infection)
Selected AbstractsAccelerated induction of mycobacterial antigen-specific CD8+ T cells in the Mycobacterium tuberculosis -infected lung by subcutaneous vaccination with Mycobacterium bovis bacille Calmette,GuérinIMMUNOLOGY, Issue 4 2009Dilara Begum Summary Both CD4+ and CD8+ T cells are important in protection against Mycobacterium tuberculosis infection. To evaluate the effect of vaccination with Mycobacterium bovis bacille Calmette,Guérin (BCG) on the CD8+ T-cell response to pulmonary M. tuberculosis infection, we analyzed the kinetics of CD8+ T cells specific to the mycobacterial Mtb32a309,318 epitope, which is shared by M. tuberculosis and M. bovis BCG, in the lung of mice infected with M. tuberculosis. The CD8+ T cells were detected by staining lymphocytes with pentameric major histocompatibility complex (MHC) class I H-2Db,Mtb32a209,318 peptide complex and were analysed by flow cytometry. Mtb32a-specific CD8+ T cells became detectable on day 14, and reached a plateau on day 21, in the lung of M. tuberculosis -infected unvaccinated mice. Subcutaneous vaccination with M. bovis BCG in the footpads induced Mtb32a-specific CD8+ T cells in the draining lymph nodes (LNs) on day 7 and their numbers further increased on day 14. When M. bovis BCG-vaccinated mice were exposed to pulmonaryinfection with M. tuberculosis 4 weeks after vaccination, the Mtb32a-specific CD8+ T cells in the infected lung became detectable on day 7 and reached a plateau on day 14, which was 1 week earlier than in the unvaccinated mice. The pulmonary CD8+ T cells from the BCG-vaccinated M. tuberculosis -infected mice produced interferon-, in response to Mtb32a209,318 peptide on day 7 of the infection, whereas those of unvaccinated mice did not. The results demonstrate that induction of mycobacterial antigen-specific protective CD8+ T cells in the M. tuberculosis -infected lung is accelerated by subcutaneous vaccination with M. bovis BCG. [source] Miliary tuberculosis and necrotizing tuberculous fasciitis , An unusual coexistence in a rheumatoid arthritis patientINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 2 2010Hyun-Hee KWON Abstract We report a case of a 65-year-old Korean female patient with rheumatoid arthritis, who presented with extensive necrotizing fasciitis of the gluteus muscles, as an unusual initial manifestation of miliary tuberculosis. The patient had been previously treated with conventional disease-modifying antirheumatic drugs and low-dose steroids for 7 years. However, she recently developed fever, warmth and painful swelling in her right buttock. Magnetic resonance imaging indicated necrotizing fasciitis of the gluteus muscles and a fasciectomy specimen revealed a Mycobacterium tuberculosis infection. Two weeks after a fasciectomy, miliary tuberculosis of the lung was diagnosed by high resolution chest computed tomography. Soft tissue infection due to M. tuberculosis should be included as a differential diagnosis in the immunocompromised host. Clinicians should be alert to the possibility of miliary tuberculosis even in the absence of respiratory symptoms and normal chest radiograph. [source] Mycobacterium tuberculosis infection of bilateral cervical lymph nodes after renal transplantationINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2001Kiyohito Ishikawa Abstract We report the case of a 52-year-old man who underwent a renal transplantation and subsequently developed extrapulmonary tuberculosis. The immunosuppressive agent was intravenously administered continuously together with antituberculosis drugs. The tuberculosis improved and renal function has been well preserved for more than 3 years post transplantation. [source] Mononeuropathy multiplex and chylothorax as earlier manifestations of pulmonary tuberculosisJOURNAL OF INTERNAL MEDICINE, Issue 6 2005H.-A. CHEN Abstract. Mononeuropathy multiplex (MNM) and chylothorax are rare clinical disorders. The concurrence of these two disorders with Mycobacterium tuberculosis infection has not been reported. We herein report a patient who was initially diagnosed with fever of unknown origin and MNM, and then developed chylothorax. Pulmonary tuberculosis was proved 1 month after chylothorax appeared. With low-dose prednisolone 15 mg day,1 and anti-tuberculosis drugs, all these disorders completely resolved 1 year later. [source] Mycobacterium tuberculosis infection in liver transplantationLIVER TRANSPLANTATION, Issue 10 2010Baligh R. Yehia Mycobacterium tuberculosis can cause significant infections in liver transplant candidates and recipients. Its nonspecific clinical features and prolonged growth time in culture make the diagnosis difficult, and treating tuberculosis (TB) remains challenging because of significant toxicities and drug-drug interactions. The diagnosis of a latent TB infection may be accomplished with tuberculin skin testing and with the newer interferon-, release assays, although this infection may be underrecognized because of host factors. Latent TB should be treated, but the degree of liver failure and the likelihood of progression to active TB will dictate whether this should occur before or after transplantation. Patients who have a history of TB, have used muromonab-CD3 or anti-T lymphocyte antibodies, or have experienced allograft rejection or coinfection with cytomegalovirus, Pneumocystisjiroveci, or Nocardia are at the greatest risk of developing active TB. Active TB in transplant patients is difficult to treat because of drug-induced hepatotoxicity and the significant interaction between rifampin and calcineurin inhibitors. In this article, we review the epidemiology, clinical features, and evaluation of transplant candidates and recipients. In addition, we offer recommendations on the appropriate diagnostic and treatment regimens for patients with latent and active TB infections. Liver Transpl 16:1129,1135, 2010. © 2010 AASLD. [source] Tuberculosis in liver transplant recipients: A systematic review and meta-analysis of individual patient data,LIVER TRANSPLANTATION, Issue 8 2009Jon-Erik C. Holty Mycobacterium tuberculosis (MTB) causes substantial morbidity and mortality in liver transplant recipients. We examined the efficacy of isoniazid latent Mycobacterium tuberculosis infection (LTBI) treatment in liver transplant recipients and reviewed systematically all cases of active MTB infection in this population. We found 7 studies that evaluated LTBI treatment and 139 cases of active MTB infection in liver transplant recipients. Isoniazid LTBI treatment was associated with reduced MTB reactivation in transplant patients with latent MTB risk factors (0.0% versus 8.2%, P = 0.02), and isoniazid-related hepatotoxicity occurred in 6% of treated patients, with no reported deaths. The prevalence of active MTB infection in transplant recipients was 1.3%. Nearly half of all recipients with active MTB infection had an identifiable pretransplant MTB risk factor. Among recipients who developed active MTB infection, extrapulmonary involvement was common (67%), including multiorgan disease (27%). The short-term mortality rate was 31%. Surviving patients were more likely to have received 3 or more drugs for MTB induction therapy (P = 0.003) and to have been diagnosed within 1 month of symptom onset (P = 0.01) and were less likely to have multiorgan disease (P = 0.01) or to have experienced episodes of acute transplant rejection (P = 0.02). Compared with the general population, liver transplant recipients have an 18-fold increase in the prevalence of active MTB infection and a 4-fold increase in the case-fatality rate. For high-risk transplant candidates, isoniazid appears safe and is probably effective at reducing MTB reactivation. All liver transplant candidates should receive a tuberculin skin test, and isoniazid LTBI treatment should be given to patients with a positive skin test result or MTB pretransplant risk factors, barring a specific contraindication. Liver Transpl 15:894,906, 2009. © 2009 AASLD. [source] Tumor necrosis factor neutralization results in disseminated disease in acute and latent Mycobacterium tuberculosis infection with normal granuloma structure in a cynomolgus macaque modelARTHRITIS & RHEUMATISM, Issue 2 2010Philana Ling Lin Objective An increased risk of tuberculosis has been documented in humans treated with tumor necrosis factor , (TNF,),neutralizing agents. In murine models, impaired signaling by TNF causes exacerbation of both acute and chronic infection associated with aberrant granuloma formation and maintenance. This study was undertaken to investigate immune modulation in the setting of TNF neutralization in primary and latent tuberculosis in a non-human primate model. Methods Cynomolgus macaques 4 years of age or older were infected with Mycobacterium tuberculosis and subjected to clinical, microbiologic, immunologic, and radiographic examinations. Monkeys were classified as having active or latent disease 6,8 months after infection, based on clinical criteria. Monkeys used in acute infection studies were randomized to receive either adalimumab (prior to and during infection) or no treatment. Monkeys with latent infection that were randomized to receive TNF-neutralizing agent were given either an inhibitor of soluble TNF, recombinant methionyl human soluble TNF receptor I (p55-TNFRI), or adalimumab. Control monkeys with latent infection were given no treatment or saline. Data from previously studied monkeys with active or latent disease were also used for comparison. Results Administration of TNF-neutralizing agents prior to M tuberculosis infection resulted in fulminant and disseminated disease by 8 weeks after infection. Neutralization of TNF in latently infected cynomolgus macaques caused reactivation in a majority of animals as determined by gross pathologic examination and bacterial burden. A spectrum of dissemination was noted, including extrapulmonary disease. Surprisingly, monkeys that developed primary and reactivation tuberculosis after TNF neutralization had similar granuloma structure and composition to that of control monkeys with active disease. TNF neutralization was associated with increased levels of interleukin-12, decreased levels of CCL4, increased chemokine receptor expression, and reduced mycobacteria-induced interferon-, production in blood but not in the affected mediastinal lymph nodes. Finally, the first signs of reactivation often occurred in thoracic lymph nodes. Conclusion These findings have important clinical implications for determining the mechanism of TNF neutralization,related tuberculosis. [source] Mycobacterium tuberculosis infection may protect against allergy in a tuberculosis endemic areaCLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2006C. C. Obihara Summary Background Epidemiological studies have shown an inverse relation of mycobacterial infection and the frequency of allergic diseases and asthma. Recent evidence suggests that allergic inflammation may be inhibited in the presence of chronic and persistent infections, such as that by Mycobacterium tuberculosis (MTB). The relation of tuberculin skin test (TST) size, an accepted marker of MTB infection and the frequency of allergic disease symptoms has not been reported from an area where MTB infection is endemic. Objective To investigate the association of TST and allergic disease symptoms, in children living in a tuberculosis (TB) endemic area. Methods In this cross-sectional study, 841 children aged 6,14 years from randomly selected household addresses in two poor communities of Cape Town, South Africa, were investigated with TST and standardized International Study on Asthma and Allergies in Childhood-based questionnaire on allergic disease symptoms. Results Children with positive TST (10 mm) were significantly less likely to have allergic disease symptoms, in particular allergic rhinitis (AR) (adjusted odds ratio 0.43; 95% confidence interval 0.24,0.79) than those with negative TST. This association remained significant after adjusting for possible confounders and correcting for the effect of clustering (>1 child per household address) in the sample. There was a significant inverse linear trend in the relation of TST size in millimetre and the frequency of allergic disease symptoms, in particular AR (P<0.001). Conclusions These results of inverse association of strong TST reaction and allergic disease symptoms in children from a TB endemic area are in support of the hypotheses that allergic inflammation may be inhibited by chronic infections, such as MTB. [source] P2X7 and NRAMP1/SLC11 A1 gene polymorphisms in Mexican mestizo patients with pulmonary tuberculosisCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2007P. Niño-Moreno Summary Tuberculosis remains one of the most important infectious diseases worldwide. Several studies have suggested that genetic factors may affect susceptibility to tuberculosis, but the specific genes involved have not yet been fully characterized. NRAMP1/SLC11 A1 and P2X7 genes have been linked to increased risk for tuberculosis in some African and Asiatic populations. To explore the potential role of these genes in the susceptibility to pulmonary tuberculosis in a Mexican mestizo population, we evaluated the association of D543N and 3,-UTR polymorphisms in NRAMP1/SLC11 A1 and ,,762 and A1513C polymorphisms in P2X7 genes with the risk for tuberculosis. Polymerase chain reaction (PCR) amplification of genomic DNA followed by restriction fragment length polymorphism analysis, and allelic-specific PCR was employed. We found no significant differences in allelic frequency in NRAMP1/SLC11 A1 gene polymorphisms in 94 patients with tuberculosis compared to 100 healthy contacts. Similarly, no significant association of the P2X7,762 gene polymorphism with tuberculosis was detected. In contrast, the P2X7 A1513C polymorphism was associated significantly with tuberculosis (P = 0·02, odds ratio = 5·28, 95% CI, 0·99,37·69), an association that had not been reported previously. However, when the function of P2X7 was assessed by an l -selectin loss assay, we did not find significant differences in patients compared to healthy contacts or between PPD+ and PPD, control individuals. This study further supports the complex role of P2X7 gene in host regulation of Mycobacterium tuberculosis infection, and demonstrates that different associations of gene polymorphisms and tuberculosis are found in distinct racial populations. [source] Feasibility of commercial interferon-,-based methods for the diagnosis of latent Mycobacterium tuberculosis infection in Finland, a country of low incidence and high bacille Calmette,Guérin vaccination coverageCLINICAL MICROBIOLOGY AND INFECTION, Issue 8 2007T. Tuuminen Abstract The performances of the QuantiFERON-TB Gold in Tubes (QFGT), T SPOT-TB (ELISPOT) and the Mantoux test were compared for the diagnosis of latent tuberculosis infection in Finland, a country of low tuberculosis incidence. In Cohort A (16 students), freshly isolated peripheral blood mononuclear cells (PBMCs), and in Cohort B (21 school children), cryopreserved PBMCs, were used for the ELISPOT assay. Cryopreservation of cells in fetal calf serum, but not in serum-free medium, produced false-positive results. Discrepancies between the results of the assays were observed. It was concluded that the accuracy of these ex-vivo methods needs additional evaluation. [source] | |||||||||||||||||||