[Objective] To study the effect of treatment of latent tuberculosis infection (LTBI) on QuantiFERONRTB-2G (QFT-2G) test results.
[Subjects an d methods] QFT-2G was used for a contact investigation in a junior high school and those positive or doubtful positive (TB Antigen-Nil response ≥ 0.1 and <0.35IU/ml) were indicated for treatment of LTBI with IN H. All subjects who completed treatment of LTBI were re-tested with QFT-2G approximately 1 month after completion of treatment and a subset were again re-tested 8 to 11 months after the completion of treatment. The levels of IFN- γ response in each QFT-2G test were compared.
[Results] Initiall y, 43 subjects (28 Q1-, 11-2Gp ositive and 15 doubtful positive) were indicated treatment of LTBI, and 41 (95 %) completed 6-months treatment. These 41 subjects were re-tested with QFT-2G approximately 1 month after the completion of treatment. Among 28 pre-treatment positives, 19 remained positive, 6 became doubtful positive, and 3reverted to negative. Among 13 pre-treatment doubtful positives, 1 converted to positive, 5 remained doubtful positive, and 7 reverted to negative. The QFT-2G responses after the completion of treatment significantly declined compared with the pre-treatment level (geometric means; before treatment ESAT-6: 0.30 IU/ml, CFP-10: 0.09 IU/ml, after treatment ESAT-6: 0.18 IU/ml, CFP-10: 0.05 IU/ml, dependent t-test; ESAT-6: p= 0.020, CFP-10: p = 0.005). At 8 to 11 months after the completion of treatment, 30 randomly selected subjects received the third QFT-2G test. Among 19positives at the completion of treatment, 14 remained positive, 4 become doubtful positive, and 1 reverted to negative. Among 8 doubtful positives at completion of treatment, 4 converted to positive, 3 remained doubtful positive, and I reverted to negative. A further decline of QFT-2G responses was not observed. Three subjects negative at the completion of treatment were re-tested and remained negative at the third test.
[Conclusion] Q FT-20 responses significantly decline d after the treatment of LTBI, despite the rate of reversion in QFT-2G being low. This low reversion rate suggests QFT-20 would not be useful as a marker to evaluate the success of treatment for LTBI. However, the finding that QFT-2G responses significantly decline after the treatment of LTBI suggests the possibility that this decline could be used as a marker of the susceptibility of the infective M. tuberculosis. strain to the prophylactic drug used. The outbreak investigation has been carried out for over two years, and none of 229 students who were TST positive, but QFT-2G negative and because of this result not indicated treatment of LTBI, have developed TB, suggesting that QFT-2G reflects TB infection more accurately than the TST, even in school children.

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[Objectives] The objectives were to report how to promote tuberculosis (TB) control including DOTS (Directly Observed Treatment, Short-course) programs, and to evaluate the results of TB control programs in Shinjuku Ward (Shinjuku-ku).
[Setting and characteristics] Inhabitants and TB patients in Shinjuku Ward. Shinjuku Ward is located in the center of metropolitan Tokyo and has typical urban TB problems, such as high incidence rate and TB among foreigners and the homeless. The TB incidence rates in Shinjuku Ward decreased from 83.9 per 100, 000 population in 1999 to 42.5 per 100, 000population in 2006, however, the rates were still two times higher than the national average. Therefore, one of the important TB programs in Shinjuku has been to actively detect cases among high-risk groups such as foreigners and the homeless.
[Methods] We observed the trend of case dete ction rates by health examination with chest X-ray among different highrisk groups, and compared the treatment outcomes before and after DOTS program execution. We also reviewed the changes of re-treatment rates and drug resistance rates.
[Results] The case detection rates of T B by health examinations of foreign students at Japanese language schools decreased from 0.49% in 1996 to 0.13% in 2006 (p = 0.021). Although the case detection rates decreased, they were still about 26 times higher than those of Japanese students. While, the case detection rates among the homeless remained high with 4.7%, 3.3%, 4.5% and 3.6% in 1999-2002, respectively, since 2003, however, they had decreased and no TB cases were detected in 2005-2006. The DOTS program for homeless TB patients has been carried out since 2000 and that for the foreigners since 2003. The rates of defaulting during treatment before DOTS were very high among both homeless patients (21.4%) and foreigners (29.8%) in 1998-1999. However, after the introduction of DOTS program, those rates declined to 10.4% (p= 0.014) among the homeless and 7.8%(p = 0.002) among foreigners in 2002-2004. The propo rtion of newly notified patients with previous TB treatment and those with multi-drug resistant TB (MDR-TB) have also decreased after the introduction of DOTS programs. From 2000-2002 to 2003-2006, the re-treatment rates decre ased from 19.4% to 10.0% (p< 0.001) and MDR-TB rates decreased from 1.6% to 0.2% (p =0.042), respectively.
[Discussion] The key points of TB co ntrol in Shinjuku Ward are to detect TB cases early especially among the highrisk groups, and to assist all TB patients to complete their treatment. In order to expand this strategy, besides promoting active case findings among high-risk groups, we have developed many types of DOTS programs, considering each patient's lifestyle and cooperating with school teachers at schools, pharmacists at pharmacies, home-care specialists at homes or facilities for the elderly, and so on. Among others, a major premise for the homeless and some other socially disadvantaged patients was to guarantee the provision of medicine and living by introducing social welfare services, before starting DOTS programs. This approach might have helped to reduce the defaulting rate, relapse rate and MDR-TB rate.

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[Purpose] To investigate the factors relating to defaulting from tuberculosis treatment in Japan, and clarify what is needed to prevent defaulting. [Object] Tuberculosis patients who were registered at public health centers (PHCs), and interrupted treatment for more than 2 months without the doctors' direction at the end of December 2005.
[Method] In vestigation by questionaire sent by post-mail to all public health centers (608 PHCs) in Japan.
[Result] The valid answers was obtai ned from 89.0% (541/608) of PHCs. Tuberculosis patients who had interrupted treatment, but could be contacted by PHCs' staff were 137, and for those patients the factors relating to defaulting from treatment were analyzed. The factors were classified into 7 categories (there may be more than one factors in one patients); factors related to disbelief and/or prejudice for diagnosis and/or treatment (except factors related to drug adverse effects) were observed in 51.8%, factors related to economical problem in 24.1%, factors related to job or studies in 23.4%, factors related to drug adverse effects in 22.6%, factors related to visiting out-patients departments in 6.6%, psychiatric disease and/or drug abuse in 4.4%, others in 9.5%.
[Conclusion] It is needed to prevent defaulting, first, to improve the quality of tuberculosis medical care and services including good and sufficient explanations on TB and how to cure it to patients, and proper managements for drug adverse effects, and then to expand public economical support for the costs of medicine and travel expenses to medical facilities and to make accessible time and place of the tuberculosis outpatient clinic more convenient and flexible for patients.

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[Purpose] The bacilli which were isolated from a patient suspected of the mixed infections with Mycobacterium avium and Mycobacterium intracellulare, were analyzed. The genotypes of M. avium in the sedimented fractions of treated sputum and in some colonies isolated from Ogawa medium were compared by the Variable Numbers of Tandem Repeats (VNTR).
[Object and method] Case: A woman, aged 57. Mycobacterial species isolated from some colonies by culture in 2004 and 2006 and from the treated sputum in 2006, were determined by DNA sequencing analysis of the 16S rRNA gene. Also, by using VNTR, the genotype of mycobacteria was analyzed.
[Results] (1) The colony isolated from Ogawa medium in 2004 was monoclonal M.avium. (2) By VNTR analyses of specimens in 2006, multiple acid-fast bacteria were found in the sputum sediment and in isolated bacteria from Ogawa medium. (3) By analyses of 16S rRNA DNA sequence, M.avium and M.intracellulare were found in the colonies isolated from the sputum sediment and the Ogawa medium in 2006. (4) The same VNTR patterns were obtained in M.avium in 2004 and 2006 when single colony was analyzed. (5) From the showerhead and culvert of the bathroom in the patient's house, M.avium was not detected.
[Discussion] By VNTR analyses, it was considered that the mixed infections of M.avium and M.intracellulare had been generated during treatment in this case. Therefore, in the case of suspected complex infection, VNTR analysis would be a useful genotyping method in M.avium complex infection.

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