Funayama Kazushi, Tsujimoto Aiko, Mori Masaaki, Yamamoto Hiromi, Fujiwara Keiko, Nishimura Tomoyasu, Hasegawa Naoki, Horiguchi Itsuko, Mori Toru, Marui Eiji
Yokohama City Kohoku Public Health and Welfare Center, 26-1, Daizutocho, Kohoku-ku, Yokohama-shi, Kanagawa 222-0032 Japan.
Kekkaku. 2005 Jul;80(7):527-34.
This study examined the usefulness of QuantiFERON TB-2G (QFT) i.e., a novel technique for detecting tuberculosis infection based on the whole blood interferon-gamma response to specific antigens, in the investigation of a tuberculosis outbreak among university students.
One university student was diagnosed as smear-positive pulmonary tuberculosis. In order to determine the extent of tuberculosis infection among contact students, tuberculin skin tests and QFT were performed on the close-contact group (220 people), as well as on the non-close-contact group (242 people).
Nine students were found to be TB either clinically or on the X-ray screening in the contact investigation. In the close-contact group, the QFT-positive rate was 32.7%. The proportion of those exhibiting tuberculin reactions with erythema diameters of 30 mm or larger was 57.7%. In the non-close-contact group, the QFT-positive rate was only 0.8 %, as expected from the current healthy Japanese youths of this age. In contrast, strong tuberculin reactions with erythema of 30 mm or larger were seen in 18.2% in the latter group, most likely due to the previous history of BCG vaccination.
QFT was clearly demonstrated to be a useful method for diagnosing tuberculosis infection, especially among subjects who show tuberculin reactivity due to past BCG vaccination. At the same time, the current criteria for the indication of chemoprophylaxis based on the strong tuberculin reaction were considered to be unreliable, causing many subjects with strong reactions to be given unnecessary preventive medications.
本研究探讨了全血干扰素-γ对特定抗原反应检测结核感染的新技术——结核感染QuantiFERON-TB-2G（QFT）在大学生结核病暴发调查中的应用价值。
一名大学生被诊断为涂片阳性肺结核。为确定接触学生中结核感染的程度，对密切接触组（220人）和非密切接触组（242人）进行了结核菌素皮肤试验和QFT检测。
在接触者调查中，9名学生临床或X线筛查发现患有结核病。密切接触组中，QFT阳性率为32.7%。红斑直径30mm或更大的结核菌素反应者比例为57.7%。非密切接触组中，QFT阳性率仅为0.8%，与当前该年龄健康日本青年的预期相符。相比之下，后一组中18.2%出现红斑直径30mm或更大的强结核菌素反应，很可能是由于既往卡介苗接种史。
QFT被明确证明是诊断结核感染的一种有用方法，尤其是在因既往卡介苗接种而表现出结核菌素反应性的受试者中。同时，基于强结核菌素反应的化学预防指征现行标准被认为不可靠，导致许多有强反应的受试者接受了不必要的预防性药物治疗。
