• Pediatric Infection and Vaccine
• /
• v.6 no.1
• /
• pp.101-106
• /
• 1999

Purpose : Tuberculosis, a major public health problem, is an important cause of childhood infectious diseases. To decrease the tuberculosis morbidity rate, BCG vaccination and chemoprophylaxis are performed. Recently 2TU PPD skin test was introduced as a diagnostic method for tuberculous infection. We studied the positive conversion rate of 2TU PPD test after percutaneous multiple puncture BCG vaccination. Methods : Four hundred seventy six infants from well baby clinic of Samsung Cheil Hospital were enrolled. They were immunized with percutaneous multiple puncture technique BCG(Japan BCG laboratory, Japan) at 1 month of age. Approximately 6 months later, tuberculin skin test using RT23 2TU PPD was performed. Induration size, family history of tuberculosis and number of BCG scars were evaluated. Induration greater than or equal to 5mm was defined as positive conversion. Results : Among 476 infants, 248(52.1%) were male and 228(47.9%) were female. PPD skin tests were performed $6.2{\pm}0.5$($mean{\pm}S.D.$) months after BCG vaccination. Mean induration size was $7.3{\pm}3.2mm$ and positive conversion rate was 85.5%. Total number of BCG scars was $15.5{\pm}3.2$. Conclusion : The seroconversion rate by 2TU PPD test after percutaneous multiple puncture BCG vaccination was high. But, more comparative studies with various age groups may be needed for 2TU PPD test used as diagnostic method of tuberculosis in the hospitals.

• Tuberculosis and Respiratory Diseases
• /
• v.53 no.4
• /
• pp.401-408
• /
• 2002

Background : Tuberculin skin test is a method to examine M. tuberculosis infection and has been used all over the world. But various factors make it difficult to understand testing results. In 2000, the American Thoracic Society recommended that skin test results should be decided by considering risk factors of the tested. In Korea, high tuberculosis infection rate and BCG vaccination rate make it difficult to differentiate current infection, past infection, and no infection by the skin test. This study was attempted to examine a negative predictive value of the skin test to understand how the skin test acts on deciding administration of anti-tuberculosis drug. Methods : From Mar. 1 to Jul. 31 in 2001, the test was performed for patients hospitalized in Department of Internal Medicine, Hallym University College of Medicine, Chunchon, Korea by administering Tuberculin PPD RT23 2 TU (0.1 ml)to them that has been currently used in Korea based on Mantoux method. They were decided to be infected with tuberculosis bacilli by following diagnostic standard: 1) tuberculosis bacilli was cultured in sputum by microbiological diagnostic standard or Acid-fast bacilli was proven on a microscopic examination or 2) tuberculosis bacilli was not proven in the aforesaid microbiological test by clinical diagnostic standard, while there was opinion or symptom suitable for tuberculosis by radiographic or histological standard so the doctor decided to apply the tuberculosis treatment. Results : In this study, total 210 patients except 20 patients (8.7%) among 230 hospitalized patients were evaluated. Their average age was 60±16.8 years, and male-female rate was 1.28 : 1 (male: 118, female: 92). Number of patient, who was diagnosed and decided as tuberculosis, was 53(25.2%). Pulmonary tuberculosis was found in 45 patients (84.9%); 22 patients were decided to be positive in the Acid-fast bacilli smear test by microbiological examination (culture positive: 13, culture negative: 9), and 23 patients were decided to be tuberculosis patients by clinical diagnosis standard. Tuberculosis pleuritis was found in 8 patients (15.1%); 4 patients were diagnosed and decided by histological standard, and 4 patients were decided and treated by clinical standard. In differentiating patients into 'Negative' and 'Positive' by the skin test standard of the American Thoracic Society, negative predictive value 92.3%, positive predictive value 47.3%, sensitivity and specificity were 83%, 68.8%, respectively. Conclusion : In hospitalized respiratory patients, there was high negative predictive vlaue 92.3% by tuberculin skin test, therefore skin test would be a important factor for deciding administration of anti-tuberculosis drug on negative skin test patient.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.1
• /
• pp.13-25
• /
• 1999

Background: Ineffective cell-mediated immune response in human tuberculosis is associated with a depressed Thl cytokine response and reduced production of IFN-$\gamma$. Most persons infected with Mycobacterium tuberculosis are healthy tuberculin reactors with protective immunity, but a minority with ineffective immunity develop extensive pulmonary tuberculosis. The cell-mediated immune response is an important aspect of host resistance to mycobacterial infection and is believed to be tightly regulated by a balance between Th1 cytokines including IFN-$\gamma$, IL-12, IL-18, regulated on activation, normal T cell expressed and secreted (RANTES) and Th2 counterparts such as IL-4, monocyte chemoattractant protein-l (MCP-l). Methods: Proliferation and mRNA expression of IFN-$\gamma$, RANTES and MCP-l by RT-PCR in peripheral blood mononuclear cells (PBMCs) in response to in vitro stimulation with mycobacterial antigens were compared in pulmonary tuberculosis patients with cured and treatment failure and in tuberculin-positive and tuberculin-negative healthy subjects. Results: Defective proliferative responsiveness to aqueous TSP antigen was involved with treatment failure tuberculosis patients. Aqueous TSP antigen-induced IFN-$\gamma$ and RANTES mRNA expression was decreased in treatment failure tuberculosis patients compared with healthy tuberculin reactors and cured tuberculosis patients (23.1 % versus 90.0% for IFN-$\gamma$ and 46.2% versus 70.0% versus 46.2% for RANTES). The frequency of MCP-l mRNA expression to aqueous TSP antigen in treatment failure tuberculosis patients was greater than in healthy tuberculin reactors and cured tuberculosis patients (76.9% versus 40.0%). Conclusion: The increasing expression of MCP-1 mRNA in response to aqueous TSP antigen might be predicted to favor Th1 responses and restricted Th1 responses in treatment failure of pulmonary tuberculosis.

• Tuberculosis and Respiratory Diseases
• /
• v.65 no.4
• /
• pp.269-276
• /
• 2008

Background: Although the prevalence of tuberculosis infections (PTBI) is one of the basic epidemiologic indices, no survey has been carried out since 1995 because the nation-wide tuberculosis prevalence survey was changed to a surveillance system. Subjects without a BCG scar are examined in a tuberculin survey. However, it is very difficult to select these subjects under high vaccination coverage. It is important to evaluate the impact of BCG vaccinations on the tuberculin response and estimate the PTBI regardless of the BCG vaccination status. Methods: A nation-wide, school-based cross-sectional tuberculin survey was carried out among first graders in elementary school in 2006. A total of 5,148 children in 40 schools were selected by quota sampling. Tuberculin testing with 0.1 ml of two tuberculin units of PPD RT23 was carried out on 4,018 children. The maximum transverse diameter of induration was measured 48 to 72 hours later. The presence of a BCG scar was checked separately. Results: There were no BCG scars in 6.3% of the subjects. The mean induration size of tuberculin testing was $3.7{\pm}4.4mm$, which included 1,882 (46.8%) subjects with an induration size of 0 mm. The PTBI was 10.9% (439 subjects) using a cut-off point of ${\geq}10mm$ (conventional method). The annual risk of tuberculosis infections (ARTI) was 1.9% when the mean age of the subjects was assumed to be 6 years. There was no difference in the PTBI according to the presence or absence of a BCG scar [11.2% vs 7.6% (OR: 1.54, 95% CI: 0.98~2.43)]. Using a mirror image technique with 16 mm as the cut-off point, the PTBI and ARTI had decreased to 2.4% and 0.4% respectively. Conclusion: PTBI and ARTI, as estimated by conventional methods, appear to be high among BCG vaccinated children. A mirror image technique is more suitable for estimating the indices in a country with an intermediate burden of tuberculosis than the conventional method.

• 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.