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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00557765
Recruitment Status : Completed
First Posted : November 14, 2007
Last Update Posted : November 14, 2007
Ligue Pulmonaire Genevoise
Information provided by:
University Hospital, Geneva

Brief Summary:
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.

Condition or disease
Tuberculosis Latent Tuberculosis Infection

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
Actual Enrollment : 295 participants
Observational Model: Case-Only
Time Perspective: Prospective
Official Title: 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
Study Start Date : October 2004
Actual Study Completion Date : January 2006

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Tuberculosis
U.S. FDA Resources

Primary Outcome Measures :
  1. Correlation between results of TST and IGRA tests and exposure scores [ Time Frame: 2 months after exposure ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
All subjects screened after exposure to a case of active and contagious tuberculosis in the Geneva area

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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00557765

Centre antituberculeux; Geneva University Hospital
Geneva, Switzerland, 1211
Sponsors and Collaborators
University Hospital, Geneva
Ligue Pulmonaire Genevoise
Principal Investigator: Jean-Paul Janssens, M.D. Centre antituberculeux Identifier: NCT00557765     History of Changes
Other Study ID Numbers: 04-184
First Posted: November 14, 2007    Key Record Dates
Last Update Posted: November 14, 2007
Last Verified: November 2007

Keywords provided by University Hospital, Geneva:
Latent tuberculosis infection
Interferon gamma release assay
Contact tracing

Additional relevant MeSH terms:
Latent Tuberculosis
Mycobacterium Infections
Actinomycetales Infections
Gram-Positive Bacterial Infections
Bacterial Infections
Antineoplastic Agents
Antiviral Agents
Anti-Infective Agents