• 보건세계
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• 제53권7호통권599호
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• pp.35-39
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• 2006

결핵균이 몸 속에 들어와서 결핵균 특이T-림프구의 분화 및 증식을 자극하여 투베르클린 검사 양성을 보일 정도로 충분한 숫자의 결핵균 특이T-림프구들이 형성될 때 까지는 약 4주가 소요된다.

• 대한의생명과학회지
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• 제24권2호
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• pp.138-142
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• 2018

The incidence of tuberculosis (TB) in the Republic of Korea remains high when compared to the incidence in other Organization for Economic Cooperation and Development (OECD) countries. The prompt diagnosis and effective treatment of latent TB infection (LTBI) are very important in terms of controlling the burden of TB. The tuberculin skin test (TST) has long been the "gold standard" assay for the diagnosis of LTBI. However, it can show false positive results due to Bacille Calmette-$Gu{\acute{e}}rin$ (BCG) vaccination and infection with many environmental nontuberculous mycobacteria (NTM). The interferon gamma release assay (IGRA) using Mycobacterium tuberculosis (MTB)-specific antigens, was developed for the detection of LTBI. The QuantiFERON-TB Gold In-Tube assay is one of the most commonly used forms of the IGRA. In order to compare the diagnostic efficacy of the TST and IGRA in relation to LTBI among BCG-vaccinated healthy donors, whole blood samples were collected from 51 participants, and the results of the TST and IGRA were compared. Of the 51 cases, 18 cases (35.3%) were positive and 33 cases (64.7%) were negative when using the TST, while four cases (7.8%) were positive and 47 cases (92.2%) negative when using the IGRA. There was no correlation between the size of the induration in the TST and the $IFN-{\gamma}$ protein level. In conclusion, the TST showed higher cross-reactivity among the BCG-vaccinated healthy participants, therefore, the IGRA might be the most suitable assay for the rapid screening of LTBI in BCG-vaccinated healthy population, or for TB contact investigation.

• Tuberculosis and Respiratory Diseases
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• 제81권1호
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• pp.59-72
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• 2018

Background: It remains uncertain if $interferon-{\gamma}$ release assays (IGRAs) are superior to the tuberculin skin test (TST) for the diagnosis of active tuberculosis (TB) or latent tuberculosis infection (LTBI) in immunosuppressed populations including people with human immunodeficiency virus (HIV) infection. The purpose of this study was to systematically review the performance of IGRAs and the TST in people with HIV with active TB or LTBI in low and high prevalence TB countries. Methods: We searched the MEDLINE database from 1966 through to January 2017 for studies that compared results of the TST with either the commercial QuantiFERON-TB Gold in Tube (QFTGT) assay or previous assay versions, the T-SPOT.TB assay or in-house IGRAs. Data were summarized by TB prevalence. Tests for concordance and differences in proportions were undertaken as appropriate. The variation in study methodology was appraised. Results: Thirty-two studies including 4,856 HIV subjects met the search criteria. Fourteen studies compared the tests in subjects with LTBI in low TB prevalence settings. The QFTGT had a similar rate of reactivity to the TST, although the first-generation version of that assay was reactive more commonly. IGRAs were more frequently positive than the TST in HIV infected subjects with active TB. There was considerable study methodology and population heterogeneity, and generally low concordance between tests. Both the TST and IGRAs were affected by CD4 T-cell immunodeficiency. Conclusion: Our review of comparative data does not provide robust evidence to support the assertion that the IGRAs are superior to the TST when used in HIV infected subjects to diagnose either active TB or LTBI.

• 한국동물위생학회지
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• 제30권2호
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• pp.233-241
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• 2007

Tuberculin positive cattle without gross tubercle lesions should be confirmed by the bacteriological examination to determine the state of the infection. To overcome the time-consuming and laborious identification by culture and biochemical tests, polymerase chain reaction (PCR) has been used to identify Mycobacterium bovis. Due to various lipids in the cell wall of Mycobacterium spp, novel methods of DNA extraction from Mycobacterium spp have been developed. In this study, a newly developed guanidium isothiocyanate/silica DNA extraction method was directly applied to specimens from the tuberculin positive cattle. DNAs were directly extracted from the lymph nodes and the major polymorphic tandem repeat (MPTR) and mycobacterial protein of BCG 70 (MPB70) were amplified using PCR. The DNA extraction method using guanidium isothiocyanate/silica was efficient and safe, and the MPTR and MPB70 primers were specific to M bovis. Therefore, MPTR and MPB70 PCRs will be useful for the detection of M bovis in the lymph node from skin-test positive cattle.

• Tuberculosis and Respiratory Diseases
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• 제72권2호
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• pp.140-148
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• 2012

Background: Detection and treatment of tuberculosis (TB) infection with contact investigation is a key component of TB control program. I evaluated the prevalence and risk factors for TB infection among contacts of recently diagnosed pulmonary TB patients in a tertiary hospital in Korea. Methods: 206 contacts of 90 adult pulmonary TB patients underwent tuberculin skin tests (TST) and chest radiography. The TST results were considered positive with an induration of 10 mm or more, suggesting TB infection. A standardized questionnaire was used to assess risk factors associated with TB infection. Results: TST was positive in 97 of 206 contacts of TB patients (47.1%) and positive rate of TST increased with age. The risk of TB infection was significantly associated with close contact with TB patients (sleeping in the same room) (odd ratio [OR], 4.94; 95% confidence interval [CI], 1.43~17.00). Conclusion: TB infection rate was higher in the elderly, and the risk of TB infection was significantly increased with close contact of TB patients.

• 보건세계
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• 제63권1호
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• pp.5-7
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• 2014

우리나라 인구의 약 1/3이 결핵에 감염된 것으로 알려져 있다. 많은 사람들이 이 대목에서 깜짝 놀란다. '국민 3명 중 1명이 감염자라고?' 감염이 곧 '결핵'을 의미하는 것은 아니다. 하지만 감염이 된 사람은 언제든 결핵으로 진전될 가능성을 안고 있는, 잠재적 결핵환자이다. 이 페이지에서는 내 몸에 결핵균이 들어왔는지 여부를 확인 할 수 있는 TST, 즉 투베르쿨린 피부검사에 대해 알아보기로 한다.

• Tuberculosis and Respiratory Diseases
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• 제60권5호
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• pp.497-509
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• 2006

Until recently, the tuberculin skin test (TST) has been the only tool available for diagnosing a latent TB infection. However, the development of new diagnostic tools, using the Mycobacterium tuberculosis (MTB)-specific early secreted antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) antigens, should improve the control of tuberculosis (TB) by allowing a more accurate identification of a latent TB infection (LTBI). Antigen-specific interferon-gamma ($IFN-{\gamma}$) assays have greater specificity in BCG-vaccinated individuals, and as less biased by nontuberculous mycobacterial infections. Many comparative studies have suggested that those assays have a higher specificity than the TST, and the sensitivity of these assays are expected to remarkably improved if more MTB-specific antigens can become available. Nevertheless, the major obstacle to the widespread use of these tests is the limited financial resources. Similar to other diagnostic tests, the predictive value of $IFN-{\gamma}$ assays depends on the prevalence of a MTB infection in the population being tested. Therefore, prospective studies will be meeded to establish the applicability of these new assays at multiple geographic locations among patients of different ethnicities, and to determine if the $IFN-{\gamma}$ responses can indicate those with a high risk of progressing to active TB.

• Tuberculosis and Respiratory Diseases
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• 제80권1호
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• pp.21-26
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• 2017

It is well established that health care workers (HCWs) have a considerably higher risk of occupationally acquired tuberculosis (TB). To reduce the transmission of TB to HCWs and patients, TB infection control programs should be implemented in health care settings. The first and most important level of all protection and control programs is administrative control. Its goals are to prevent HCWs, other staff, and patients from being exposed to TB, and to reduce the transmission of infection by ensuring rapid diagnosis and treatment of affected individuals. Administrative control measures recommended by the United States Centers for Disease Control and Prevention and the World Health Organization include prompt identification of people with TB symptoms, isolation of infectious patients, control of the spread of the pathogen, and minimization of time spent in health care facilities. Another key component of measures undertaken is the baseline and serial screening for latent TB infection in HCWs who are at risk of exposure to TB. Although the interferon-gamma release assay has some advantages over the tuberculin skin test, the former has serious limitations, mostly due to its high conversion rate.

• Tuberculosis and Respiratory Diseases
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• 제65권4호
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• pp.269-276
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• 2008

연구배경: 결핵 감염률은 결핵 실태를 파악하기 위한 기본 지표임에도 불구하고 1995년 전국실태조사를 마지막으로 실시되지 못하고 2000년 결핵정보감시체계로 대체되었다. 비시지 접종률이 높은 현 상황에서 무반흔자를 대상으로 한 감염률 조사는 실행이 어려우며 비시지 접종자를 대상으로 투베르쿨린 조사에 대한 비시지 영향 분석과 비시지 반흔과 상관없는 결핵 감염률 조사가 필요하다. 방 법: 2006년에 전국 초등학교 1학년생들을 대상으로 각 시도별 아동 수를 추계한 후 학교를 대상으로 단면조사 연구를 하였다. 총 대상자 수는 40개 학교의 5,148명이 비례할당법으로 선정, 조사되었다. 투베르쿨린 검사는 2단위의 PPD RT 23 0.1 ml를 좌측 전박에 피내 주사한 후 48~72시간 후에 가장 긴 횡직경을 측정하였다. 비시지 반흔에 대해서도 각각 조사하였다. 결 과: 비시지 무반흔자는 6.3%였다. 평균 경결 크기는 0 mm 반응자 1,882명(46.8%)를 포함하여 $3.7{\pm}4.4mm$ 였다. 결핵 감염률은 10 mm 이상을 양성 반응으로 했을때 10.9% (439명)였다. 연간결핵감염위험률은 평균 연령을 6세로 하여 1.91%였다. 결핵 감염률은 비시지 반흔유무에 따른 유의한 차이는 없었다[11.2% vs. 7.6% (OR:1.54, 95% CI: 0.98~2.43)]. 16 mm를 정점으로 한 거울영상법으로는 감염률과 연간결핵감염위험률이 각각 2.4%와 0.4%였다. 결 론: 결핵 감염률과 연간결핵감염위험률은 기존 방법으로 할 경우 높은 비시지 접종률로 인해 높게 나타났다. 결핵 감염률이 높지 않은 국가에서는 거울영상법이 두 지표를 추정하는데 보다 더 적합한 것으로 보인다.

• Tuberculosis and Respiratory Diseases
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• 제68권6호
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• pp.328-333
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• 2010

Background: There are several active tuberculosis (TB) cases in Korean high schools each school year. The risk of transmission in schools is extremely high due to the considerable time spent in closed classrooms. We evaluated the control of latent tuberculosis infection in Korean high schools. Methods: When a student was identified with active TB, tuberculin skin testing was performed on their classmates and on students in their same school grade. When a student had a positive tuberculin skin tests (TST), they underwent follow-up testing with QuantiFERON-TB Gold In-Tube (QFT). The manufacturer recommended a cut-off of 0.35 IU/mL to determine QFT positivity was applied. Results: A total of 131 pulmonary tuberculosis (TB) patients were included based on the criteria for screening TB contacts in the National Tuberculosis Control Program. Seventy-five (57.2%) students tested smear positive. TST were performed on 7,109 students who were classmates of, or in the same grade as, a TB patient. Of the contacts, 1,231 students (17.3%) were TST positive and they were screened with QFT. Six hundred-sixty-six (55.0%) of the tested students returned a positive QFT result and the rate of positivity was significantly associated with the increasing size of TST indurations (p<0.0001). Conclusion: The use of QFT resulted in approximately 45% of TST positive students not being given chemoprophylaxis.