• Tuberculosis and Respiratory Diseases
• /
• v.79 no.3
• /
• pp.127-133
• /
• 2016

Tuberculosis (TB) is one of the most important occupational risks for healthcare workers (HCWs) in South Korea. Many policies regarding the control and prevention of TB in healthcare settings recommend that HCWs are tested for latent tuberculosis infection (LTBI) in addition to active TB. Moreover, the Korean Tuberculosis Prevention Act also recommends that HCWs receive regular testing for LTBI. However, there are no specific or detailed guidelines for dealing with LTBI in HCWs. Herein, we discuss the diagnosis and treatment of LTBI in HCWs and focus particularly on the baseline screening of hired HCWs, routine follow-up, and contact investigation.

• Tuberculosis and Respiratory Diseases
• /
• v.86 no.2
• /
• pp.94-101
• /
• 2023

A recent understanding of the dynamic continuous spectrum of Mycobacterium tuberculosis infection has led to the recognition of incipient tuberculosis, which refers to the latent infection state that has begun to progress to active tuberculosis. The importance of early detection of these individuals with a high-risk of progression to active tuberculosis is emphasized to efficiently implement targeted tuberculosis preventive therapy. However, the tuberculin skin test or interferon-γ release assay, which is currently used for the diagnosis of latent tuberculosis infection, does not aid in the prediction of the risk of progression to active tuberculosis. Thus, a novel test is urgently needed. Recently, simultaneous and systematic analysis of differentially expressed genes using a high-throughput platform has enabled the discovery of key genes that may serve potential biomarkers for the diagnosis or prognosis of diseases. This host transcriptional investigation has been extended to the field of tuberculosis, providing promising results. The present review focuses on recent progress and challenges in the field of blood transcriptional signatures to predict progression to active tuberculosis.

• Tuberculosis and Respiratory Diseases
• /
• v.39 no.4
• /
• pp.334-342
• /
• 1992

Background: The activated T lymphocyte by inhalaed mycobacterial antigen may evoke cell-mediated immunity in patients with active pulmonary tuberculosis. These activated lymphocyte may influence the response of tuberculin-purified protein derivative (PPD) in skin test. But occasionally, anergy to PPD appear in patients with pulmonary tuberculosis in spite of active stage. Thus we evaluated the effect of change of subtypes of lymphocyte in bronchoalveolar lavage fluid (BAL) and peripheral blood on anergy to PPD in patients with active pulmonary tuberculosis. Method: We performed tuberculin skin test and flow-cytometry analysis of lymphocytes obtained from BAL fluid and peripheral blood in 11 healthy normal volunteers and 20 patients with active pulmonary tuberculosis. Results: 1) The composition of lymphocyte significantly increased in patients with active pulmonary tuberculosis when compared with that in healthy control ($25.2{\pm}4.8$ vs $6.5{\pm}1.3%$, p<0.01), but composition of monocyte significantly decreased ($69.6{\pm}5.7$ vs $89.2{\pm}1.4%$, p<0.05) in analysis of BAL fluid. 2) There were no differences in compositions of cells in BAL fluid between responders and no-responders to PPD. 3) The compositions of CD3 (+), CD4 (+), CD3 (+) IL-2R (+), CD3 (+) HLA-DR (+) significantly increased in BAL fluid when compared with those in peripheral blood in patients with active pulmonary tuberculosis. But the composition of CDS (+), CD4/CDS were not different between BAL fluid and peripheral blood. 4) There were no correlations between response to PPD and compositions of cells and lymphocyte subtypes in BAL fluid and peripheral blood in all patients with tuberculosis, responders, and no-responders, respectively. Conclusion: From these results, we suggest no direct relationship between compositions of inflammatory cells in bronchoalveolar lavage fluid and we could not rule out the possibility of compartmentalization of activated lymphocyte involving in anergy to PPD in skin test in patients with active pulmonary tuberculosis.

• Tuberculosis and Respiratory Diseases
• /
• v.57 no.2
• /
• pp.101-117
• /
• 2004

현증 결핵환자가 감소하고, 면역억제환자가 증가하고 있는 국내 추세에서 잠복결핵(latent tuberculosis)의 진단 및 치료 지침이 필요한 실정이다. 그러나 결핵의 유병률, 발생률 그리고 비씨지 접종률 등이 외국과 다른 국내의 현실에서 현증이 없는 잠복결핵의 진단 및 치료에 대한 방침은 필연적으로 외국과 다를 수 밖에 없으며, 현 시점에 국내에서 이에 대한 자료가 불충분하여 국내의 환경에 적합한 근거 중심의 지침을 설정하기는 어려운 상황이다. 그러나 결핵의 기본 병태 생리를 근거로 하여 최소한 결핵균 감염 이후 결핵 발병의 위험성이 높은 대상 환자에서는 잠복결핵 진단을 위한 검사를 시행하여 치료 여부를 결정하여야 한다. 고위험군은 사람면역결핍바이러스(human immunodeficiency virus, HIV) 감염자, 장기이식환자, 면역억제제를 장기간 사용하는 환자, 6세 이하의 소아 중 최근 전염성 결핵환자 접촉자 등을 우선적으로 고려해야 한다. 미국은 발병 위험도의 고, 중, 저에 따라 투베르쿨린 검사(tuberculin skin test, Mantoux test)의 양성기준을 달리 하여 잠복결핵을 진단하고 있으나, 국내에는 아직 이에 대한 자료가 부족하므로 발병의 위험이 높은 상기 고위험군을 대상으로 하여 PPD RT-23 2TU (Tuberculin unit)를 이용한 피부반응검사에서 10mm이상의 경결(induration)이 생성되는 경우를 양성으로 정하고 추후 연구 결과에 따라 재조정이 필요하다. 그 동안은 투베르쿨린 검사 결과 5-10 mm 사이의 경결반응을 보이는 면역억제 환자에 대하여는 개별적으로 의사의 판단에 따라 잠복결핵의 진단 및 치료 여부를 결정한다. 그러나 면역억제제를 사용하는 등 결핵 발병의 고위험군에서는 피부반응검사상 음성이라도 과거 결핵 치료력이 없이 흉부사진상 명백하게 과거에 결핵을 앓은 흉터가 남아있는 경우(석회화된 1차 결핵 소견은 제외)에는 잠복결핵의 치료를 시행한다. 상기 잠복결핵의 진단 및 검사의 적응증은 최소한 시행하여야 할 경우를 나열한 것으로 이외의 환자에 대하여는 환경 및 대상에 따라 개별화되어야 한다. 치료제로는 isoniazid (INH) 9개월 매일 치료(최소 한 6개월 이상, HIV양성 환자인 경우는 9개월), rifa-mpicin (RFP) 4개월 치료 및 INH/RFP 3개월 매일 치료를 시행할 수 있다. 상기 치료가 어려운 경우에는 RFP/pyrazinamide (PZA) 2개월 매일 치료를 고려할 수 있으나 중증 간독성의 가능성에 대한 철저한 교육 및 추적검사가 필요하다. 향후 국내 환경의 변화 및 연구결과에 따라 추후 부족한 부분에 대한 지침의 재정립이 필요하다.

• Pediatric Infection and Vaccine
• /
• v.17 no.2
• /
• pp.137-147
• /
• 2010

Purpose : The purpose of this study is to evaluate the usefulness and limitation of QuantiFERON-TB Gold (QTB) for diagnosis of latent tuberculosis in children. Methods : The medical records of 112 children who were tested by tuberculin skin test (TST) and QTB for detection of latent tuberculosis (TB) in Eulji General Hospital during the period from January 2007 to June 2009 were retrospectively reviewed. Results : Of the 112 participants, the clinical TB group included 15 (13.4%), the contact group included 43 (38.4%), and the non-contact group included 54 (48.2%). Positive rates of TST and QTB were 100% and 80% in the clinical TB group, 64% and 14% in the close contact group, 27% and 0% in the casual contact group, and 52% and 2% in the non-contact group, respectively. Sensitivity of QTB was 80.0% and specificity was 92.6%. Agreement between QTB and TST was poor ($\kappa$=0.209). We also confirmed that the positive rate of QTB increased as the age of the patient increased (P=0.011). A QTB indeterminate result was observed in 11 (9.8%) subjects. QTB was retested in 15 subjects. In 5 of the 6 subjects who had positive results initially, positive results persisted for a median 2.2 months after termination of treatment. Conclusion : Although QTB was associated with several problems, including low sensitivity and a high rate of indeterminate results, it had clinical importance due to its high specificity. We found good correlation with regard to exposure and QTB positivity, including that of young children under 5 years of age. However, clinical application of interferon-$\gamma$ releasing assay for young children for diagnosis of active and latent tuberculosis will require additional prospective studies.

• Tuberculosis and Respiratory Diseases
• /
• v.82 no.4
• /
• pp.306-310
• /
• 2019

Background: Tuberculosis (TB) is increasing in immigrants. We aimed to investigate the current status of latent tuberculosis infection (LTBI) treatment for North Korean Refugees (NKR) compared to South Koreans Contacts (SKC). Methods: TB close contacts in a closed facility of SKC and NKR who underwent LTBI screening in a settlement support center for NKR were analyzed retrospectively. Results: Among tuberculin skin test (TST) ${\geq}10mm$ (n=298) reactors, the males accounted for 72.2% in SKC (n=126) and 19.5% in NKR (n=172) (p<0.01). The mean age was higher in South Korea ($42.8{\pm}9.9years$ vs. $35.4{\pm}10.0years$, p<0.01). Additionally, the mean TST size was significantly bigger in NKR ($17.39{\pm}3.9mm$ vs. $16.57{\pm}4.2mm$, p=0.03). The LTBI treatments were initiated for all screened NKR, and LTBI completion rate was only 68.0%. However, in NKR, LTBI treatment completion rate was significantly increased by shorter 4R regimen (odds ratio [OR], 9.296; 95% confidence interval [CI], 4.159-20.774; p<0.01) and male (OR, 3.447; 95% CI, 1.191-9.974; p=0.02). Conclusion: LTBI treatment compliance must be improved in NKR with a shorter regimen. In addition, a larger study regarding a focus on LTBI with easy access to related data for NKR should be conducted.

• Tuberculosis and Respiratory Diseases
• /
• v.72 no.5
• /
• pp.416-425
• /
• 2012

Background: The sensitivities and specificities of interferon-gamma release assays (IGRAs) vary among different population studies, and the data on the routine use of IGRAs are limited. The aim of this study was to evaluate the role of QuantiFERON-TB Gold In-Tube (QFT-GIT) test in the diagnosis of active tuberculosis. Methods: We conducted a prospective study, enrolling 77 patients with suspected pulmonary tuberculosis (TB), at a secondary care teaching hospital in Seoul. Results: In total, 12 (15.6%) patients showed indeterminate results due to positive control failure on the QFT-GIT test. Indeterminate results were significantly associated with the elderly, history of the intensive care unit stay, lymphocytopenia, especially low CD4 count, increased C-reactive protein and decreased protein levels. Of the 77 patients, 44 (57.1%) were diagnosed with active pulmonary tuberculosis, and the percentage of false negative results of the QFT-GIT was 36.4% (vs. 31.8% with TST). In the TB group with >65 years old (n=12), the proportions of the indeterminate (33.3% vs. 3.1%) and the false negative results (58.3% vs. 25.0%) of the QFT-GIT were significantly higher than in the younger TB group (n=32). Conclusion: Indeterminate and false negative results of QFT-GIT test were not infrequent in tuberculosis, especially in the elderly. Care should be considered for the interpretation with the elderly, immunocompromised, chronic and severely diseased patients.

• Clinical and Experimental Pediatrics
• /
• v.52 no.5
• /
• pp.519-528
• /
• 2009

Tuberculosis continues to cause an unacceptably high toll of disease and death among children worldwide. Whereas intense scientific and clinical research efforts into novel diagnostic, therapeutic, and preventive interventions have focused on tuberculosis in adults, childhood tuberculosis has been relatively neglected. However, children are particularly vulnerable to severe disease and death following infection, and those with latent infection become the reservoir for future transmission following disease reactivation in adulthood, fuelling future epidemics. Therefore, it is very important to understand the significance, diagnosis and treatment of latent tuberculous infection to decrease a future disease burden of tuberculosis. Unfortunately, these concept still have not fully implicated in Korean National Tuberculosis Control Program, it should be engaged and enforced as soon as possible.

• The Korean Journal of Nuclear Medicine
• /
• v.30 no.3
• /
• pp.379-381
• /
• 1996

Technetium-99m MIBI was developed as a myocardiac perfusion imagine agent and has been used effectively in the detection and post-therapeutic evaluation of various neoplasm such as thyroid, lung, bone and breast tumors. As an infrequent findings, Tc-99m MIBI agent has shown in non-neoplastic pulmonary conditions Including fibrosing alveolitis, pulmonary actinomycosis, active pulmonary sarcoidosis, pulmonary interstitial fibrosis in progressive systemic sclerosis and active osteomyelitis. In a recent report conducted by Cetin Oncel, Tc-99m MIBI imaging is an effective method in the detection and follow-up of pulmonary tuberculosis We have also experienced Tc-99m MIBI uptake in active pulmonary tuberculosis incidentally found in a patient with suspected proliferative villonodular synovitis of the left ankle.

• Korean Journal of Veterinary Service
• /
• v.34 no.4
• /
• pp.333-339
• /
• 2011

Loop-mediated isothermal amplification (LAMP) was developed to detect Mycobacterium tuberculosis complex (MTC) and non-tuberculous mycobacterium (NTM) genomic DNA in blood samples of Korea native cattle. A set of four primers, two outer and two inner, were designed from M. bovis and M. avium genomic DNA targeting the IS6110 and 16S rRNA gene, respectively. Based on 85 Intradermal Tuberculin Test (ITT) positive blood sample and using conventional PCR and LAMP, the agreement quotient (kappa), which measures agreement beyond chance were 0.93 (conventional PCR) and 0.97 (LAMP), respectively. The detection limit of the LAMP method was $2.0{\times}10^2$ copy/ml M. bovis and M. avium cells, compared to $2.0{\times}10^3$ copy/ml M. bovis and M. avium cells for conventional PCR. These results suggest that the LAMP is a powerful tool for rapid, sensitive, and practical detection of MTC and NTM in blood samples of Korea native cattle.