• Tuberculosis and Respiratory Diseases
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• 제39권1호
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• pp.62-72
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• 1992

연구배경 : 결핵의 감염에서는 세포성면역이 중요하며 그 중에서도 T림프구가 중요한 역할을 하는 것으로 알려져 있고 조력 T림프구와 억제 T림프구의 기능의 불균형이 결핵의 발병에 있어 중요한 역할을 할 것으로 생각되고 있다. 동일한 결핵균의 감염시 일부 환자에서는 결핵의 병변이 폐에 국한되는 반면, 일부의 환자들에서는 폐의 결핵병변의 유무와 관계없이 폐외장기의 결핵이 발생되고 이러한 폐외결핵의 경우 항결핵화학요법에 잘 반응하지 않는 경우를 종종 경험할 수 있을뿐만 아니라 그 유병율의 감소도 폐결핵의 경우와는 달리 현저하지 못하여 폐결핵환자와 페외결핵환자군간의 면역기능의 차이가 의심된다. 방법 : 폐결핵환자와 폐외결핵환자군에서의 T림프구 매개성 세포성면역기능의 차이와 면역기능의 생체내검사와 생체외검사의 상관성을 규명하고자 T림프구 및 아형의 수적변화를 유세포분석법(flow cytometry)을 이용하여 측정하였고 PPD피부반응검사 및 림프아구형성을 측정하여 비교하였다. 결과 : 1) 총 림프구수는 결핵환자군에서 대조군에 비하여 유의하게 감소되어 있었으나 페결핵환자군과 폐외결핵환자군간의 차이는 없었다. 2) PPD 피부반응검사와 백혈구수는 3군간에 유의한 차이가 없었다. 3) $T_3$, $T_4$, $T_8$(+)인 세포의 백분율과 절대수는 3군간에 유의한 차이가 없었으며 $T_4/T_8$의 비도 3군간에 유의한 차이가 없었다. 4) HLA-DR(+)인 세포의 백분율과 절대수는 대조군에 비하여 결핵환자군에서 유의하게 증가되어 있었으며 $IL_2$ 수용체(+)인 세포의 백분율과 절대수도 결핵환자군에서 유의하게 증가되어 있었으나 폐결핵환자군과 폐외결핵환자군에는 유의한 차이가 없었다. 5) Concanavalin-A, Phytohemagglutinin 및 PPD 자극에 대한 림프아구형성은 3군간에 유의한 차이가 없었다. 6) $T_4$(+)인 림프구의 백분율 및 절대수와 PPD 피부반응검사의 크기사이에는 유의한 상관관계가 있었다. 결론 : 이상의 결과에서 폐결핵환자와 페외결핵환자군간에 T림프구성 매개성 세포성면역기능의 변화를 발견할 수 없었다. 그러나 본 연구만으로 세포성 면역기능의 차이를 모두 관찰하였다고 할 수는 없기 때문에 이에 대하여는 추후 연구가 필요하리라고 사료된다.

• Tuberculosis and Respiratory Diseases
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• 제78권2호
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• pp.56-63
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• 2015

A small number of viable tuberculosis bacilli can reside in an individual with latent tuberculosis infection (LTBI) without obvious clinical symptoms or abnormal chest radiographs. Diagnosis and treatment for LTBI are important for tuberculosis (TB) control in public and private health, especially in high-risk populations. The updated 2014 Korean guidelines for TB recommend that tuberculin skin tests, interferon-gamma release assays, or a combination of the two can be used for LTBI diagnosis according to age and immune status of the host as well as TB contact history. The regimens for LTBI treatment include isoniazid, rifampicin, or isoniazid/rifampicin. However, results of drug susceptibility test from the index case must be considered in selecting the appropriate drug for recent contacts. Standardized LTBI diagnosis and treatment based on the new 2014 guidelines will contribute to the effective TB control in Korea as well as to the establishment of updated guidelines.

• 대한임상검사과학회지
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• 제48권3호
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• pp.225-229
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• 2016

결핵이란 결핵균에 의한 만성 감염질환으로 결핵균이 포함된 비말액을 통해 공기감염을 일으킨다. 대부분의 결핵감염자는 전염력이 없는 잠복감염상태만 유지하나 10%의 감염자 중 절반은 감염 후 1~2년 안에 발병하게 된다. 결핵감염자와 접촉이 있는 학생 74명을 대상으로 결핵 감염자 접촉관련 사전 조사 및 흉부 X-선 검사, TST 검사 및 IGRA 검사를 실시하였다. 1차 TST 검사에서 양성자는 9명, 음성은 65명으로 나타났으며, 음성 판독자는 2차 TST검사를, 양성 판독자는 IGRA 검사를 실시하였다. 1차 TST 양성자 9명 중 IGRA 검사에서 3명이 양성자로 나와 잠복 결핵감염 치료를 실시하였다. 1차 TST결과 음성자에 대한 재확인 TST 검사는 1차와 차이가 없었다. 결론적으로 잠복결핵감염율은 74명중 3명으로 4.05%로 나타났고, 잠복결핵감염자 색출을 위해서 다른 그룹에 대한 조사도 필요하다.

• Pediatric Infection and Vaccine
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• 제18권1호
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• pp.1-14
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• 2011

Tuberculosis is a disease with high morbidity and mortality in children worldwide. Despite the decrease in the incidence of tuberculosis in Korea, more than 30,000 new patients are diagnosed each year. Active tuberculosis is less frequent in children compared to adults but the risk of miliary tuberculosis and CNS tuberculosis is much higher. The diagnosis of tuberculosis in children and adolescents is difficult due to the nonspecific symptoms upon presentation. Diagnostic work up is based on the confirmation of tuberculosis infection by tuberculin skin test, abnormal radiologic findings, and contact with an adult with active tuberculosis. Anti-tuberculosis medications are prescribed according to the drug susceptibility of the index patient. Latent tuberculosis infection plays an important role in adult tuberculosis by reactivation. Thus, it is critical to accurately diagnose latent tuberculosis in children to prevent reactivation in adulthood. Korean guidelines for diagnosis and treatment of tuberculosis in children and adolescents provide evidence based recommendations in the optimal diagnosis and treatment for active and latent tuberculosis in children and adolescents based on the current Korean situation.

• 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.

• Journal of Preventive Medicine and Public Health
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• 제52권4호
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• pp.272-275
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• 2019

The 2018 National Guideline for Tuberculosis Control, which was published by the Korea Centers for Diseases Prevention and Control (KCDC), mandates conducting an epidemiological survey among close contacts of active tuberculosis patients at public institutions such as schools. In the procedure for these surveys, the tuberculin skin test (TST) is mandated as the screening test for latent tuberculosis infection in elementary school students. However, several guidelines recommend using the interferon-gamma releasing assay (IGRA) for contacts aged over 5 years with a Bacillus Calmette-$Gu{\acute{e}}rin$ vaccination history. The main reason for this is that IGRA has a higher specificity and lower false positive rate than TST. In addition, IGRA requires only a single visit to draw blood and the results are available within 24 hours. These advantages could promote cooperation from both parents and students in conducting these surveys. Thus, these findings regarding the benefits of IGRA for surveys of close contacts at elementary schools should be incorporated into the KCDC guideline.

• 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.

• Tuberculosis and Respiratory Diseases
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• 제78권2호
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• pp.125-127
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• 2015

We report a case of agranulocytosis caused by ethambutol in a 79-year-old man with pulmonary tuberculosis. He was referred for fever and skin rash developed on 21th day after antituberculosis drugs (isoniazid, rifampicin, ethambutol, and pyrazinamide) intake. Complete blood count at the time of diagnosis of pulmonary tuberculosis was normal. On the seventh admission day, agranulocytosis was developed with absolute neutrophil count of $70/{\mu}L$. We discontinued all antituberculosis drugs, and then treated with granulocyte colony-stimulating factor. Three days later, the number of white blood cell returned to normal. We administered isoniazid, pyrazinamide, and ethambutol in order with an interval. However, fever and skin rash developed again when adding ethambutol, so we discontinued ethambutol. After these symptoms disappeared, we added rifampicin and ethambutol in order with an interval. However after administering ethambutol, neutropenia developed, so we discontinued ethambutol again. He was cured with isoniazid, rifampicin, and pyrazinamide for 9 months.

• Tuberculosis and Respiratory Diseases
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• 제78권4호
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• pp.349-355
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• 2015

Background: The tuberculin skin test (TST) is the standard tool to diagnose latent tuberculosis infection (LTBI) in mass screening. The aim of this study is to find an optimal cut-off point of the TST+ rate within tuberculosis (TB) contacts to predict the active TB development among adolescents in school TB outbreaks. Methods: The Korean National Health Insurance Review and Assessment database was used to identify active TB development in relation to the initial TST (cut-off, 10 mm). The 7,475 contacts in 89 schools were divided into two groups: Incident TB group (43 schools) and no incident TB group (46 schools). LTBI treatment was initiated in 607 of the 1,761 TST+ contacts. The association with active TB progression was examined at different cut-off points of the TST+ rate. Results: The mean duration of follow-up was $3.9{\pm}0.9years$. Thirty-three contacts developed active TB during the 4,504 person-years among the TST+ contacts without LTBI treatment (n=1,154). The average TST+ rate for the incident TB group (n=43) and no incident TB group (n=46) were 31.0% and 15.5%, respectively. The TST+ rate per group was related with TB progression (odds ratio [OR], 1.025; 95% confidence interval [CI], 1.001-1.050; p=0.037). Based on the TST+ rate per group, active TB was best predicted at TST+ ${\geq}$ 16% (OR, 3.11; 95% CI, 1.29-7.51; area under curve, 0.64). Conclusion: Sixteen percent of the TST+ rate per group within the same grade students can be suggested as an optimal cut-off to predict active TB development in middle and high schools TB outbreaks.

• 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.