آزمایشگاه مجازی

►The tuberculin skin test – can not differentiate between latent and active disease. Tool available for diagnosis of TB infection

►Serology –blood tests to measure the humoral response to M. tuberculosis

•Has low sensibility and sensitivity – the primary response is cell mediated

•Sensitivity is high in smear positive disease but is low  in children, extra-pulmonary TB, TB/HIV

►Cell mediated immunity – circulating lymphocytes are extracted from the venous blood and exposed to antigens of M. tuberculosis and after 6-24 hrs the production of inflammatory mediators - interferon gamma is measured.

•Measures the primary immune response of humans to TB