Serial Interferon Gamma Release Assay in Latent Tuberculosis Infection

The aim of this report is to present results of serial interferon-gamma (IFN-gamma) determination (OuantiFERON-TB Gold In-Tube assay) in a 57-year-old BCG-vaccinated female: health care worker with a latent tuberculosis:infection. Increased IFN-gamma, IgA, and anti-thyroglobulin (anti-Tg) autoantibodies were recorded throughout a 13-month follow up. After 13 months the subject was clinically Healthy and free from any signs and symptoms of active tuberculosis. The increased levels of anti-Tg autoantibodies may have been a concurrent process that did not: impair the patient's immune status. Since false positive; IgA could be found in patients suffering from autoimmune thyroid diseases, it could be assumed increased IgA in this subject is a result of the positive interferences of goat anti-IgA antibodies. Although isoniazid prophylexis was not used, tuberculosis did not develop during the, follow-up period. Serial determination of IFN-gamma is necessary due to occupational exposure to tubercle bacilli.