New Generation IGRA in Immunocompromised Individuals

Study Overview
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Brief Summary
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Evaluation of a new ELISA based interferon-gamma release assay (QuantiFERON TB plus In-tube test) in immunocompromized patients

Detailed Description
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This study is designed to evaluate the performance of a new ELISA based QuantiFERON-TB plus In-tube test to identify M. tuberculosis specific immune Responses as evidence of latent infection with M. tuberculosis in immunosuppressed populations. Both qualitative and quantitative test results will be related to the level of immunodeficiency and to the presence of risk factors for prior exposure with M. tuberculosis. In addition, patients with active tuberculosis (both immunocompetent and immunocompromised individuals) will be included to evaluate a potential increase in sensitivity in these groups. Immunocompetent individuals with low risk of exposure will be analysed as a proxy to estimate specificity. Finally, this study will be extended to longitudinally assess the predictive value of a positive blood test for progression to active disease.

Official Title
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Performance of a New Generation IGRA in Immunocompromised Individuals

Conditions
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Monitoring, Immunologic, Active Tuberculosis, Tuberculosis in Solid Organ Transplant Recipients, Tuberculosis in Marrow Transplant Recipients, Tuberculosis in Rheumatoid Arthritis, Tuberculosis in Chronic Renal Failure, Tuberculosis in HIV-infected Individuals

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Individuals as specified for the study Population Written informed consent Exclusion Criteria: <18 years of age

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Immunocompetent controls<br>Control persons without immunodeficiency with and without active tuberculosis, with and without risk factors for prior exposure with M. tuberculosis | |
| Solid organ transplant recipients<br>Patients after solid organ transplantation with and without active tuberculosis, with and without risk factors for prior exposure with M. tuberculosis | |
| Stem cell transplant recipients<br>Patients after stem cell transplantation with and without active tuberculosis, with and without risk factors for prior exposure with M. tuberculosis | |
| Patients with rheumatoid arthritis<br>Patients with rheumatoid arthritis with and without active tuberculosis, with and without risk factors for prior exposure with M. tuberculosis | |
| Patients with chronic renal failure<br>Patients with chronic renal failure with and without active tuberculosis, with and without risk factors for prior exposure with M. tuberculosis | |
| Individuals with HIV infection<br>Individuals with HIV infection with and without active tuberculosis, with and without risk factors for prior exposure with M. tuberculosis | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Specificity | The percentage of negative test results will be quantified among controls and patients without risk factors for M. tuberculosis exposure. | 2 years | 
| Sensitivity | The percentage of positive test results will be quantified among controls and patients with active tuberculosis. | 2 years | 
| Indeterminate results | The percentage of indeterminate results will be quantified in immunocompetent and immunocompromised patients | 2 years | 
| Association with exposure | Results from QFT-Plus assay will be associated with risk factors for M. tuberculosis exposure | 2 years | 
| Progression | The number of individuals progressing to tuberculosis will be quantified depending on the test result at the time of screening and depending on preventive chemotherapy | 4 years |