Interferon Gamma Release Assays (IGRA) Testing Versus Tuberculin Skin Test in Renal Transplant Recipients

Study Overview
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Brief Summary
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Interferon gamma release assays (IGRA) have been shown to be more specific and sensitive for the detection of tuberculosis (latent or active infection) than the tuberculin skin test (TST) in immunocompetent individuals. However, very little data are available concerning the relative performance of IGRA and TST in immunosuppressed individuals from other causes than HIV. The investigators hypothesize that IGRAs would be more sensitive and specific than the TST in a group of renal transplant recipients under chronic immunosuppressive treatment for detecting latent tuberculosis infection.

Detailed Description
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In a recent study (Triverio PA et al. Interferon-gamma release assays versus tuberculin skin testing for detection of latent tuberculosis in haemodialysis patients. Nephrol Dial Transplant 2009; 24: 1952-6), the investigators had compared 2 IGRAs (T-SPOT.TB and Quantiferon Gold) with the TST and shown that one IGRA was clearly more sensitive than the TST but that both tests had a very low sensitivity for detecting prior TB. This study applies the same protocol to renal transplant recipients undergoing routine annual check-up visits: questionnaire with detailed collection of risk factors for latent tuberculosis infection (LTBI), history of prior contact with tuberculosis (TB), BCG (Bacille of Calmette and Guerin vaccine), prior TB or LTBI, treatment for TB or LTBI, analysis of chest X-ray for signs of prior TB, on-going treatment, level of immunosuppression (CD4 lymphocytes), simultaneous blood sampling for T-SPOT.TB and Quantiferon Gold, and tuberculin skin testing.

Official Title
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Interferon Gamma Release Assays Versus Tuberculin Skin Testing for the Detection of Latent Tuberculosis Infection in Renal Transplant Recipients

Conditions
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Latent Tuberculosis Infection

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: prior renal transplantation; age > 18; stable clinical condition Exclusion Criteria: hypersensitivity to tuberculin skin testing

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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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Renal transplant recipients<br>Inclusion criteria: All renal transplant recipients followed by the Division of Nephrology aged above 18 years, and having accepted study protocol after informed consent | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Agreement between results of QuantiFERON-Gold-in-tube and probability of latent tuberculosis infection | Agreement between probability of latent tuberculosis infection - established on the basis of a questionnaire and chest X-ray - and results of QuantiFERON-Gold-in-tube is computed | Up to 3 years | 
| Agreement between results of T-SPOT.TB and probability of latent tuberculosis infection | Agreement between probability of latent tuberculosis infection - established on the basis of a questionnaire and chest X-ray - and result of T-SPOT.TB is computed | Up to 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Agreement between results of IGRA tests and TST in renal transplant recipients | Agreement between results of IGRA testing and between each IGRA test and TST will be determined by computing kappa values | Up to 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tuberculosis, Latent tuberculosis infection, Immunosuppression, Renal transplant recipient