Use of a Gamma-IFN Assay in Contact Tracing for Tuberculosis in a Low-Incidence, High Immigration Area

November 13, 2007 updated by: University Hospital, Geneva

Production of Gamma-Interferon by Circulating Lymphocytes Exposed to Antigens Specific of Mycobacterium Tuberculosis: Contribution to the Identification of Latent Tuberculosis Infection in Contact Tracing

After exposure to an active case of tuberculosis (TB), close contacts may be infected. They are then considered as having latent tuberculosis infection (LTBI). Detecting LTBI is the main goal of contact tracing procedures after exposure to TB. Until recently, the only test available for detecting LTBI was the tuberculin skin test (TST). More recent tests are now available (Interferon-gamma release assays: IGRA), which are more specific and sensitive than the TST. This study compares the TST and an IGRA in the routine activity of contact tracing in our area.

Study Overview

Status

Completed

Detailed Description

Setting: A TB clinic in Geneva, Switzerland, a low incidence area for TB with a high immigrant population.

Aim of study: to compare results of an IGRA test (T-SPOT.TB, Oxford Immunotec, UK) and the TST, and their correlation with exposure scores in subjects exposed to cases of contagious TB.

Methods: Prospective study of all contacts screened in our area, and accepting to be included. Simultaneous recording of age, gender, origin, history of recent travels or exposure, BCG vaccination status, infectiousness of index case, 5 different exposure scores, TST, and result of the T-SPOT.TB blood test. Univariate and multivariate analysis.

Study Type

Observational

Enrollment (Actual)

295

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Geneva, Switzerland, 1211
        • Centre antituberculeux; Geneva University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

All subjects screened after exposure to a case of active and contagious tuberculosis in the Geneva area

Description

Inclusion Criteria:

  • Exposure to a case of contagious TB
  • Willingness to participate in study

Exclusion Criteria:

  • Known HIV infection
  • Known previous TB or treatment for LTBI

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Correlation between results of TST and IGRA tests and exposure scores
Time Frame: 2 months after exposure
2 months after exposure

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Jean-Paul Janssens, M.D., Centre antituberculeux

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2004

Study Completion (Actual)

January 1, 2006

Study Registration Dates

First Submitted

November 13, 2007

First Submitted That Met QC Criteria

November 13, 2007

First Posted (Estimate)

November 14, 2007

Study Record Updates

Last Update Posted (Estimate)

November 14, 2007

Last Update Submitted That Met QC Criteria

November 13, 2007

Last Verified

November 1, 2007

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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