• Tuberculosis and Respiratory Diseases
• /
• v.62 no.1
• /
• pp.5-10
• /
• 2007

Background: Korean national guidelines for examining contacts with active pulmonary tuberculosis (TB) are a tuberculin skin test (TST) and chest radiographs. The treatment of a latent TB infection as performed only in those younger than six years of age who test positive for TST. Although there is a high incidence of active TB in young Korean soldiers, the current national guidelines for controlling contacts with active TB in soldiers are insufficient. This study highlights the problems with the Korean guidelines for controlling a TB outbreak in a small military unit. Material and Methods: In December of 2005, there was a tuberculosis outbreak in a military unit with a total of 464 soldiers in Kyung Gi province. The chest radiographs were taken of all the soldiers, and TST were carried out on 408 candidates. Results: In the first screening of the chest radiographs, two active TB patients were detected. By August of 2006, four additional cases were detected, making a total of six cases after the outbreak. All the patients showed active pulmonary TB or TB pleuritis. When the results of TST in the close contacts and non-close contacts were compared, there was a significant difference in the absolute size of the induration($9.70{\pm}7.50mm$ vs. $6.26{\pm}7.02mm$, p<0.001) as well as the ratio of patients showing an induration > 10mm (50.0% vs. 32.0%, p<0.001) and 15mm (33.2% vs. 20.9%, p= 0.005). Conclusion: Although the national guidelines for managing a TB outbreak in a military unit were followed, there were continuous instances of new active TB cases. This highlights the need for new guidelines to prevent the spread of TB.

• Pediatric Infection and Vaccine
• /
• v.15 no.1
• /
• pp.52-58
• /
• 2008

Purpose : Whole blood interferon-$\gamma$ assay was developed and many studies showed its usefulness in diagnosing tuberculosis (TB) including latent tuberculosis infection (LTBI). However, assessment in children has been limited. This study was undertaken to evaluate the usefulness of QuantiFERON-TB Gold for the diagnosis of LTBI in children exposed to pulmonary TB. Methods : Children who visited Seoul National University Bundang Hospital with a history of TB exposure were enrolled from January 2006 to December 2007. They were evaluated with chest x-rays, tuberculin skin test (TST) and QuantiFERON-TB Gold test. TST was retested 3 months later for those with initial negative reactivity. Definition of LTBI was made on the basis of the TST reactivity. Results : Among the 103 children with a history of TB exposure, 49 children were tested with chest x-ray, TST, and QuantiFERON-TB Gold. Twenty-two were males. Median age was 7.5 years (range; 3 months to 14.7 years). According to TST reactivity, LTBI was in 8 (19%), no infection was in 21 (50%), possible LTBI was in 13 (31%). QuantiFERON-TB Gold test was positive in 5 of the 49 subjects (10%); 3 of the 13 subjects (23.1%) in unknown status, 1 of the 8 subjects (13%) in LTBI, and 1 of the 21 subjects (5%) without infection. The agreement between the QuantiFERON-TB Gold and the TST was poor (${\kappa}=0.101$). Conclusion : QuantiFERON-TB Gold showed poor sensitivity for the diagnosis of LTBI in children with exposure to TB. QuantiFERON-TB Gold alone does not seem to be useful in the diagnosis of LTBI in children.

• Journal of muscle and joint health
• /
• v.26 no.2
• /
• pp.120-130
• /
• 2019

Purpose: The purpose of this study was to investigate the predictors of tuberculosis (TB) drugs in health care workers diagnosed with latent tuberculosis Infection (LTBI). Methods: This study was a descriptive correlation study. Data were collected by using a self-report questionnaire. The collected data were analyzed by -test, t-test, and logistic regression analysis. Results: There were involved 160 participants, 35 (21.9%) who took the TB drugs, and 125 (73.8%) who did not take the TB drugs. The predictors on taking TB drugs in health care workers with LTBI were subjective norms (OR=3.33, p<.001), perceived sensitivity (OR=2.67, p=.026), perceived barrier (OR=0.14, p=.014), and unmarried (OR=4.69, p=.006) than married, health care worker category 2 group (OR=5.84, p=.015) and 1 group (OR=4.25, p=.022) than 3, 4 group, sleep over 7 hours (OR=4.11, p=.022) than less 7 hours sleep. Conclusion: In order to promote the use of TB drugs in health care workers with LTBI, it is necessary that take intervention strategies to increase the subjective norms and perceived sensitivity and to decrease the perceived barriers.

• The Korean Journal of Medicine
• /
• v.93 no.6
• /
• pp.509-517
• /
• 2018

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 of LTBI are important for tuberculosis (TB) control in public and private healthcare facilities, particularly in high-risk populations. The updated 2017 Korean guidelines for TB recommend that tuberculin skin tests, interferon-gamma release assays, or a combination of them can be used for the diagnosis of LTBI, depending on the age and immune status of the patient as well as their TB contact history. For diagnosis of LTBI, exclusion of active TB is essential, and the possibility of healed TB in those without a history of treatment for TB but at risk of its development must be considered. The treatment options for LTBI include isoniazid, rifampicin, isoniazid/rifampicin, and isoniazid/rifapentine. The benefits and risks of these agents based on the age of the patient and their hepatotoxicity must be considered when selecting the appropriate drug. Standardized diagnosis and treatment of LTBI based on the updated 2017 guidelines will contribute to the control of TB in Korea as well as to further revisions of the guidelines.

• Clinical and Experimental Pediatrics
• /
• v.51 no.9
• /
• pp.971-976
• /
• 2008

Purpose : Surveillance for detecting and managing latent tuberculosis infection (LTBI) is a key component of tuberculosis control. The classic surveillance tool, the tuberculin skin test (TST), may have some limitations when used in the Bacillus Calmette-$Gu{\acute{e}}rin$ (BCG)-vaccinated population. The object was to perform a blood test $QuantiFERON^{(R)}$-TB Gold In Tube (QFT-G IT) based on the detection of interferon-$\gamma$ ($IFN-{\gamma}$) released by T cells in response to Mycobacterium tuberculosis-specific antigens, and to compare the efficacy of this new diagnostic tool for LTBI with that of TST. Methods : For six months, between October 1, 2006 and April 30, 2007, data were collected from 111 patients under 15 years of age at Severance Children's Hospital. TST and QFT-G IT tests were performed with children with or without contact histories of tuberculosis. In addition to these tests, we examined comparative data from 29 adults who had tuberculosis, to detect false negative rates in the QFT-G IT method. Results : Thirty-three children had household contact histories. In this group, 15% and 42% of cases were found to be positive using the QFT-G IT assay and TST, respectively. Agreement was low between these two tests (${\kappa}=0.39$). In the adult active tuberculosis group, the QFT-G IT false negative rate defined as a positive culture and a negative QFT-G IT result was 12.5%. Conclusion : In diagnosing LTBI in children, the usefulness of a whole-blood $IFN-{\gamma}$ assay employing TB-specific antigens will be revealed only by examining additional longitudinal clinical data; this study serves as a starting point in that process.

• Pediatric Infection and Vaccine
• /
• v.22 no.1
• /
• pp.7-15
• /
• 2015

Purpose: The purpose of this study is to investigate secondary infections within the households of newly diagnosed tuberculosis patients. Methods: We collected data on household infections of tuberculosis patients by retrospective review of medical records and telephone surveys. Results: Out of 321 newly diagnosed tuberculosis cases, a total of 253 patients who received telephone surveys were enrolled in this study. Less than 50% of the patients had household contacts screened for tuberculosis infection, and most of the patients were not aware of the necessity of testing. Out of 562 household contacts, there were 8 cases of secondary tuberculosis (1.4%, 8/562) in 7 households. There were 15 cases of latent infection (2.7%, 15/562) in 13 households. Out of 110 child and adolescent household contacts, there were no cases of secondary tuberculosis, and there were 8 cases of latent infection (7.3%) in 7 households, which was 20.5% among child and adolescent contacts screened for tuberculosis infection. In 3 of the cases (13.0%) that had secondary tuberculosis or latent infection in their households, the source of infection was extrapulmonary tuberculosis. There was no correlation between the frequency of household infections and the presence of pulmonary cavities, sputum AFB smear results, and microbiologically confirmed results. Conclusions: For effective investigation of tuberculosis contacts, it is necessary to raise general awareness on the necessity of investigating household contacts, and there should also be a continued assessment on tuberculosis contact investigation since government-supported programs.

• Journal of Korean Biological Nursing Science
• /
• v.21 no.4
• /
• pp.300-307
• /
• 2019

Purpose: The purpose of this study was to provide basic data on the infection prevention management program, which is one of the infectious disease control program by identifying the prevalence and risk factors of latent tuberculosis infection (LTBI) in healthcare workers. Methods: We surveyed a total of 3,046 LTBI test results, including those of 2,269 existing staff and 777 new employees. An interferon-gamma release assay (IGRA) for the diagnosis of LTBI was performed using QuantiFERON^®-TB Gold In-Tube (QFT-IT). The risk factors of LTBI were analyzed using logistic regression analysis. Results: The overall prevalence of LTBI was 16.0% (487/3,046). The prevalence of LTBI in the existing staff was 17.9% (406/2,269) and the prevalence of LTBI in new employees was 10.4% (81/777). Multivariate logistic regression analysis revealed that the risk factors of latent tuberculosis infection among the existing staff were gender, age and work period wheres, the risk factor amongst the new employees depended on their age. Conclusion: The LTBI was not related to the type of occupation and work unit. Therefore, while establishing an infection control program for the prevention of tuberculosis infection at medical institurions, institutional heads and infection control experts should encompass a policy for all the employees.

• Proceedings of The Korean Society of Health Promotion Conference
• /
• 2005.11a
• /
• pp.234-243
• /
• 2005

상당히 성공적인 사람병원체인 결핵균을 Robert Koch가 발견한 이래, 결핵 방제의 상당한 진보에도 불구하고, 결핵의 발생은 현재까지 계속되어오고 있다(Tiruviluamala and Reichman 2002). 그러므로, 완전한 민감성과 특이성을 갖는 신속한 진단방법이 결핵과 결핵의 잠복감염을 진단하는데 요구되어지며(Tiruviluamala and Reichman 2002), 계속적으로 결핵균과 BCG의 유전체와 단백질체 연구를 통하여 결핵 방제수단이 발전되어질 것이다 (Jungblut et al. 1999). 본 연구는 PPD가 결핵을 진단하는 특이한 항원만으로 정확하게 조화를 이루고 있지 않다는 것을 보여주었으며, 그것의 역가는 결론적으로 생물학적으로 평가되어져야 하지만, PPD의 제조는 단백질체 분석 기법에 의해 분석되고 표준화될 수 있음을 보여주었다. 이를 통하여 결핵 피내진단의 일괄된 결과를 위해 PPD 사용 전에 이와같은 단백질체 분석기법을 적용할 수 있을 것으로 사료되며, 본 연구에서 밝혀진 특이 항원은 새로운 피내진단항원으로 적용될 수 있을 것으로 사료된다.

• Tuberculosis and Respiratory Diseases
• /
• v.60 no.1
• /
• pp.38-43
• /
• 2006

Background : Even though two-month rifampicin (RMP, R) and pyrazinamide (PZA, P) treatment has some advantages over isoniazid (INH, H) treatment for latent tuberculosis infection (LTBI), it was withdrawn from the list of treatment regimens for LTBI because of reported cases of severe hepatotoxicity. The purpose of this study was to estimate the frequency of hepatotoxicity of RMP and PZA treatment excluding INH in a Korean population. Method : TIn order to recruit patients who were prescribed RMP and PZA excluding INH, 256 INH-resistant tuberculosis patients were investigated through retrospective medical record analysis. A standard four-drug regimen was changed to a RMP/PZA-containing regimen excluding INH in 64 patients (RZ+ group). In the same study period, 146 patients who were prescribed an INH/RMP/PZA-containing standard regimen were randomly selected as a control (HRZ+ group). Clinical characteristics including liver diseases and the frequency of drug-induced hepatitis were compared between the RZ+ and HRZ+ groups. Result : The mean age of patients in the RZ+ group was 50.2 (${\pm}16.2$) and the male-to-female ratio was 36:28. The frequency of underlying liver diseases was 10.9% (7/64), which was not significantly different from that of the HRZ+ group (4.1%, 6/146). Even though the treatment duration of RZ+ ($5.5{\pm}4.8months$) was longer that than that of HRZ+ ($2.7{\pm}2.3months$), the frequency of toxic hepatitis was not significantly different between RZ+ and HRZ+ groups, 3.5% (2/57) and 7.1% (10/140), respectively. Conclusion : Hepatotoxicity was mild and occurred in a minor proportion of patients in a Korean population prescribed an RMP/PZA-containing regimen. A future prospective study including more patients is needed.

• Korean Journal of Clinical Laboratory Science
• /
• v.51 no.3
• /
• pp.323-328
• /
• 2019

Tuberculosis, a chronic bacterial infection caused by Mycobacterium tuberculosis (MTB), differs in its status latency and activity because of the characteristics of MTB, immune status of the host, and genetic susceptibility. The host defense mechanism against MTB is caused mainly by interactions between macrophages, T cells, and dendritic cells. CD44 is expressed in activated T cells when infected with MTB and regulates lymphocyte migration. In addition, CD44 mediates leukocyte adhesion to the ECM and plays a role in attracting macrophages and $CD4^+$ T cells to the lungs. Therefore, genetic polymorphism of the CD44 gene will inhibit the host cell immune mechanisms against MTB. This study examined whether the genetic polymorphism of the CD44 gene affects the susceptibility of tuberculosis. A total of 237 SNPs corresponding to the CD44 genes were analyzed using the genotype data of 443 tuberculosis cases and 3,228 healthy controls from the Korean Association Resource (KARE). Of these, 17 SNPs showed a significant association with the tuberculosis case. The most significant SNP was rs75137824 (OR=0.231, CI: 1.51~3.56, $P=1.3{\times}10^{-4}$). In addition, rs10488809, one of the 17 significant SNPs, is important for the tuberculosis outbreak can bind to the JUND and FOS transcription factors and can affect CD44 gene expression. This study suggests that polymorphism of the CD44 gene modulates the host susceptibility to tuberculosis in a variety of ways, resulting in differences in the status of tuberculosis.