中国结核感染现状（英文版）

Latent Infection of Tuberculosis in China HUASHAN HOSPITAL, FUDAN UNIVERSITY, Shanghai, China Wenhong Zhang, M.D unknown for latent infection) Factors leading to False-Positive TST Reactions Nontuberculous mycobacteria Reactions caused by nontuberculous mycobacteria are usually 10 mm of induration BCG vaccination Reactivity in BCG vaccine recipients generally wanes over time; positive TST result is likely due to TB infection if risk factors are present T SPOTTM detect INF-r released by specific T cells Collect white cells using BD CPT tube or Ficoll extraction. Add white cells and TB antigens to wells. T cells release interferon gamma. Interferon gamma captured by antibodies. Incubate, wash and add conjugated second antibody to interferon gamma. Add substrate and count spots by eye or use reader. Each spot is an individual T cell that has released interferon gamma. How does T-spot Technology Work Patient Whole blood Sample PBMC ESAT-6 CFP10 T cell secreting INF Ab capture INF Blue spot 2 commercial Kit available for detecting latent or active tuberculosis T cell-based assay for interferon gamma, the enzyme-linked immunosorbent spot test (ELISPOT), has promise in the diagnosis of Mycobacterium tuberculosis infection after exposure to a known tuberculosis (TB) patient. Commercialisation of two T cellbased tests for the diagnosis of M. tuberculosis infection (T Spot TB by Oxford Immunotec and Quantiferon-TB Gold by Cellestis) T-cell based assay is recommended for detecting infection of M. Tb measures individual reacting T cells: Even individual cells can be detected in a sample. Therefore even those who are severely immunocompromised, if a single cell reacts then it can be detected. measures all types of T cells: Both CD4 and CD8 type T cells are detected. Therefore if one type of T cells is depleted in a patient (e.g. CD4 T cells in HIV infected patients) a response can still be detected from the CD8 T cells. This sensitivity is key to the tests excellent performance in immunosuppressed populations The strategic for treating latent infection of tuberculosis in China? Lifetime Risk of Reactivation Tuberculosis C. Robert Horsburgh. n engl j med 2004;350;20:2060-7 Latent infection of tuberculosis in China: Treat or not Treat? BCG strategic or “find and treat” strategic? Condition