北京市学龄前儿童结核菌自然感染的研究

北京市从１９７８年成功实施现代结核病控制措施，结核病疫情明显好转，为掌握结核自然感染率及其在现代结核病控制措施下的下降趋势。在对新生儿及儿童采取一系列保护性预防措施的情况下，自１９８８年７月１５日于顺义县开始停止新生儿卡介苗接种。１９９５年对首批未接种卡介苗的６～７岁即１９８８～１９８９年出生的队列进入小学一年级的学生采用国际标准ＰＰＤ及国际标准结素试验技术进行结核菌素试验。１９９５年顺义县６～７岁儿童的结核感染率为１．３５％，估算年结核感染率为０．２１％，说明现代结核病控制措施对结核病感染的显著影响。顺义县１９８８～１９９５年０～４岁未接种卡介苗的儿童中结核性脑膜炎的发生继续减少。研究结果为评价现代结核病控制措施的效果及在不同结核病流行病学条件下修订卡介苗接种政策提供科学依据。     

Tuberculous meningitis in Japanese children between 1980-1991]

We evaluated the clinical and laboratory findings of tuberculous meningitis admitted to Tokyo Metropolitan Children's Hospital from 1980 through 1991 retrospectively. They consisted of 26 patients (14 boys and 12 girls), and their age ranged from 4 months to 11 years. Seventeen patients were under 3 years of age. Mortality rate was 4% (1/26), and there were 13 patients with sequelae on discharge from the hospital, and 12 patients without any sequelae. The period to recover normal CSF findings was relatively long. Some cases which did not seem to respond well to chemotherapy at the initial stage, recovered from meningitis without sequelae. This suggests that it is not necessary to change the chemotherapy at the initial few weeks of therapy. The risk factors of poor prognosis were; age less than 2 years, decreased level of consciousness on admission, convulsion, CSF protein more than 70 mg/dl, and CSF glucose less than 20 mg/dl. Tryptophan reaction was not always positive. Chloride in CSF was not so important to diagnose tuberculous meningitis in children. For the proper diagnosis of tuberculous meningitis in children one should consider several factors such as tuberculin skin test, family history, chest X-ray findings and CSF study. BCG was inoculated in six children (three patients were under one year old and the rests were older than 4 years). In three patients under one year old BCG was seemed to be inoculated after Mycobacterium tuberculosis infection, and apparently not effective to prevent tuberculosis meningitis. We conclude that BCG vaccination is necessary in early infancy to prevent tuberculous meningitis.     

黑龙江省儿童结核性脑膜炎流行趋势分析

目的研究黑龙江省结核性脑膜炎（结脑）十年来发病的变化趋势以便采取有力措施控制该病发生。方法统计每年各市、县结核病防治所登记的已确诊的１４周岁以下结脑发病人数，对比研究其变化及主要原因。结果结脑发病率呈明显下降趋势，１９８２年与１９９２年发病率分别为９．５８／１０万与２．１７／１０万，年递降率１３．８％。结论政府重视，改善人民生活，化疗控制传染源，认真接种卡介苗是结脑发病下降的有效措施。     

Tuberculous meningitis in France in 1990: characteristics and impact of BCG vaccination

Setting: France, 1990.Objective: To measure the incidence and describe the characteristics of bacteriologically-confirmed tuberculous meningitis (TBM) and to estimate the protective efficacy of BCG vaccination in children aged less than 5 years.Design: An active surveillance of TBM cases confirmed by positive cerebrospinal fluid (CSF) culture was conducted through a network of microbiology laboratories serving 99.8% of regional and district general hospitals and other large private hospitals.Results: A total of 70 cases were reported: 61% were adults over 44 years, 64% were males and 77% were born in France. 7 patients were known to be infected with HIV. 6 cases were observed in children aged less than 5 years, 2 of whom had been vaccinated with BCG. 3 of the 6 children died (one had been BCGvaccinated). Given the 80% coverage of BCG in this age group, the protective efficacy of BCG vaccination was estimated to be 87.5% (95% CI: 30–98), which indicates that 14 TBM cases may have been prevented by BCG vaccination in 1990.Conclusion: Results are consistent with the number of TBM cases expected on the basis of a 0.04% annual risk of infection. Current BCG vaccination policy in France still has a measurable impact on the incidence of tuberculous meningitis in children under 5 years of age. Given the probable continuous decrease of the annual risk of infection in future years, alternative policies should be considered.     

Childhood tuberculosis in the State of Qatar: the effect of a limited expatriate screening programme on the incidence of tuberculosis.

OBJECTIVE: To determine incidence rates and the effectiveness of the expatriate screening programme on paediatric tuberculosis (TB) in the State of Qatar. METHOD: A state-wide, population-based, retrospective analysis of all cases of tuberculosis among children 0-14 years of age reported to the TB Unit of the Division of Public Health during 1983-1996. RESULTS: One hundred and forty-four children with tuberculous disease were identified, with a steadily declining incidence rate (rate of notification) from 11/100000 children (0-14 years) population in 1983 to 7/100000 in 1996. This decrease in the childhood TB case notification rate correlated with foreign-born children, older children and the implementation of expatriate screening in 1986. Diagnosis in 56% of children was made abroad or within 3 months of arrival from vacation and 30% within one year of arrival. Comparison of the three age groups (<5, 5-9 and 10-14 years) showed no significant difference with regard to nationality, sex, type of TB, radiological findings and screening. However older children were more likely to be symptomatic (P < 0.0001) and to have positive tuberculin skin test (TST) reactivity (P = 0.012), culture (P < 0.0001), and gastric aspirates (P = 0.018). CONCLUSION: Although there was a 36% decrease in paediatric TB incidence after the implementation of expatriate screening in 1986, Qatar has a high rate of paediatric tuberculosis. The policy of BCG vaccination at birth should be continued, and screening children at school entry and on return from vacation would be useful for further case identification.     

Tuberculin reactivity in a pediatric population with high BCG vaccination coverage.

SETTING: The tuberculin skin test (TST) is often included in diagnostic algorithms for tuberculosis (TB) in children. TST interpretation, however, may be complicated by prior Bacillus Calmette-Guerin (BCG) vaccination. We assessed the prevalence of and risk factors for positive TST reactions in children 3 to 60 months of age in Botswana, a country with high TB rates and BCG coverage of over 90%. METHODS: A multi-stage cluster survey was conducted in one rural and three urban districts. Data collected included demographic characteristics, nutritional indices, vaccination status, and prior TB exposure. Mantoux TSTs were administered and induration measured at 48-72 hours. RESULTS: Of 821 children identified, 783 had TSTs placed and read. Of the 759 children with vaccination cards, 755 (99.5%) had received BCG vaccine. Seventy-nine per cent of children had 0 mm induration, 7% had > or =10 mm induration ('positive' TST), and 2% had > or =15 mm. A positive TST was associated with reported contact with any person with active TB (odds ratio [OR] 1.9; 95% confidence interval [CI] 1.02-3.6), or a mother (OR 5.1; 95% CI 2.1-12.4) or aunt (OR 5.3; 95% CI 2.0-14.0) with active TB. TSTs > or =5 mm (but not > or =10 mm) were associated with presence of a BCG scar. Positive reactions were not associated with age, time since BCG vaccination, clinical signs or symptoms of TB, nutritional status, crowding, or recent measles or polio immunization. CONCLUSION: The TST remains useful in identifying children with tuberculous infection in this setting of high TB prevalence and extensive BCG coverage.     

Trend in the annual risk of tuberculous infection in Egypt, 1950-1996.

OBJECTIVE: To determine the trend in the risk of tuberculous infection in non-BCG vaccinated children in Egypt in the period 1950-1996. METHODS: In 1949-1952, a tuberculin survey was carried out in Egypt by the World Health Organization (WHO) covering 103 districts. In 1995-1997 a tuberculin survey was carried in 73 620 primary school children in grade one in the same districts, using international guidelines. The trend in tuberculous infection was determined by comparing the prevalence of Mantoux reactions of > or =6 mm in the two surveys in subjects without apparent BCG scar aged 6-7 years. For an estimate of current risk of infection the 17 mm cut-off point (number with 17 mm plus twice the number with greater than 17 mm) was used. RESULTS: In 1995-1997, 76% of children had a BCG scar. Infection prevalence estimates in 14 766 non-BCG-vaccinated children with a mean age of 6.7 years were 11.9%, 4.1%, and 2.1% for the cut-off points 6 mm, 10 mm, and 17 mm, respectively. Decline in the risk of infection was estimated to be in the order of 50% over 45 years, or 1.5% per year. The geometric mean annual risk of infection in the 6.7 years before the survey was estimated at 0.32% (95% confidence interval 0.27-0.40%). For Egypt, the incidence of smear-positive tuberculosis was estimated at 16 per 100000 population, giving a case detection rate of 85% (range 56-100%). CONCLUSION: This survey has shown that the size of the tuberculosis problem in Egypt is considerably smaller now than it was 45 years ago.     

Tuberculin response of Sri Lankan children after BCG vaccination at birth

A total of 740 healthy children aged between 3 months and 11 years who had received BCG vaccination in the first month of life were Mantoux tested in Sri Lanka. Despite 97% having a visible scar following vaccination, 80% showed Tuberculin anergy (0-1 mm). Those without a scar showed no response. There was no correlation between scar size and the Mantoux response. A low mean Mantoux reaction was seen at all ages: 3.5 mm at 3 months, 3.2 mm at 18 months, 1.8 mm at 5-7 years and 1.9 mm at 9-11 years. A significant waning of the Mantoux reaction occurred at 5-7 years but there was no significant change at 9-11 years. Children who had received routine revaccination at 10 years, having received the first at birth, had a significantly higher mean Mantoux reaction (9.6 mm) when tested 3 months after revaccination. In 90 bacteriologically proven tuberculous patients, there was a significantly increased Mantoux reaction compared to all other groups. 1 T.U. PPD RT 23 (with tween 80) was used in all instances for Mantoux testing. The present study shows that routine BCG vaccination at birth, using a reduced dose of 0.05 ml, is unlikely to interfere subsequently with the diagnostic value of the Mantoux test. However, revaccination at 10 years may do so.     

The impact of directly-observed treatment on the epidemiology of tuberculosis in Beijing.

SETTING: Fully supervised chemotherapy, or directly observed treatment (DOT), for newly detected smear-positive cases in Beijing, has been successfully implemented for two decades. OBJECTIVE: To evaluate the progress made in tuberculosis control, and in particular to evaluate the impact of DOT on tuberculosis epidemiology in Beijing. DESIGN: Epidemiological parameters on tuberculosis, consisting of mortality, prevalence, notification rate, tuberculous meningitis in children and initial drug resistance rate, were collected and analysed. Their trends were evaluated and compared with DOT implemented for new smear-positive cases in Beijing from 1978 to 1996. RESULTS: The coverage of DOT for new smear-positive pulmonary tuberculosis cases has increased from 10% in 1978 to more than 90% since 1990. Since DOT was introduced in 1978, mortality from tuberculosis has declined by an average of more than 7% per year. The reduction rate of 17.2%, and the rates of chronic cases and tuberculous meningitis in children decreased dramatically. The rate of newly registered smear-positive cases decreased from 18.9/100000 in 1986 to 7.3/100000 in 1996, giving an average annual reduction rate of 9.1 during this period. Initial resistance to isoniazid and streptomycin decreased from respectively 13.9% and 12.3% in 1978-1979 to 4.2% and 5.8% by 1996. The level of multidrug resistance was low and stable, at 0.8% in 1996. CONCLUSION: The experience of the Beijing tuberculosis control programme convincingly demonstrates that it is possible to improve the epidemiological situation rapidly in a low-income country, at very low cost and in a manner that is self-sufficient and sustainable.     

Tuberculin survey among school-aged children in Ahvaz, Iran, 2006.

BACKGROUND AND OBJECTIVE: The tuberculin test is widely used for the diagnosis of tuberculosis (TB) in children, as it is the only one to provide evidence of infection with Mycobacterium tuberculosis. Our objective was to estimate the prevalence of TB infection, the annual risk of infection (ARI), and the incidence of active TB in school children. METHODS: A cross-sectional study was carried out in Ahvaz, a city of southern Iran, in 2006. A questionnaire was used to collect information, including demographic characteristics, bacillus Calmette-Guérin (BCG) vaccination history, and household contact with active TB. Tuberculin testing was performed. Reactivity that measured < 5 mm was considered negative, between 5 and 9 mm was considered doubtful, and > or = 10mm was considered positive. Chest radiographs were obtained as part of the evaluation for children with a positive result. RESULTS: A total of 3906 children with a mean+/-standard deviation (SD) age of 10.59+/-2.63 years (51% female, 49% male) were entered into our study. Of these, 3338 children (85.5%) did not develop a reaction (0mm), 243 (6.2%) had reactivity of 1-4mm, 238 (6.1%) had reactivity of 5-9 mm, and 87 (2.2%) had reactivity of > or = 10 mm. More than 90% of the children had received the BCG vaccine in the first week of life. The ARI rate was 0.5% and the estimated case of smear-positive TB was approximately 25 per 100000 population. Only three children were diagnosed with active TB, a prevalence of 75 per 100000 population. CONCLUSIONS: Tuberculin testing using 5TU-PPD (5 tuberculin units of purified protein derivative) is a valuable diagnostic test for latent TB and active TB in childhood. BCG vaccination has no remarkable effect on the interpretation of tuberculin reactivity. The incidence rate of active pulmonary TB in children in the region of study is of concern.     

Protective value of BCG vaccination in children in Bangkok, Thailand

The protective effect of bacille Calmette-Guérin (BCG) vaccination against tuberculosis is controversial. In a study, 330 patients less than 12 years of age with tuberculosis, 52.1% of whom had had BCG vaccination, were compared with a control group of 1106 patients free of tuberculosis, 81% of whom had BCG vaccination. The occurrence of disseminated forms of tuberculosis, tuberculous meningitis, tuberculous peritonitis, and tuberculosis of bone and joints in BCG-vaccinated patients was quite low. With BCG vaccination, the incidence of the disseminated form of tuberculosis was significantly lower than that of pulmonary tuberculosis with pulmonary parenchymal lesions, primary pulmonary complexes, and pleural effusion. Tuberculous peritonitis was significantly less frequent than pulmonary tuberculosis with pulmonary parenchymal lesions, enlarged hilar glands, pulmonary primary complex, and pleural effusions. The study demonstrated that BCG gave an overall protective effect of 74% and that a major effect of this immunity was to produce a localized form of tuberculosis.     

Tuberculin survey in the Eastern Province of Saudi Arabia

We present the results of the Mantoux test (5 units tuberculin) survey in the Eastern Province of Saudi Arabia, which was conducted as part of a nationwide epidemiological survey of tuberculosis. A total of 1105 subjects were screened out of whom 630 gave a history of BCG vaccination in the past and 363 were BCG-negative. Among BCG-negative children aged 5-14 years, only 5% had a positive Mantoux, a rate lower than most Third World countries but higher than developed countries were under 2% of children are tuberculin reactors. This calls for continuation of free treatment of active cases and increased efforts towards screening of contacts. The results also vindicate the current policy of giving BCG vaccine at birth and probably indicates the need to revaccinate at school leaving age, in accordance with WHO recommendations. Tuberculin reactivity rose steeply with age (32% at age 15-24 and 72% at age 45-64 years) indicating the presence of a large pool of subjects at risk of breaking into active disease. Finally, 71% (201/283) of children aged 5-14 years who had received BCG vaccine at birth, reacted negatively to the Mantoux test. This supports the findings of previous studies that in the majority of subjects, BCG-induced tuberculin sensitivity fades a few years after vaccination.     

Contact examination for tuberculosis in Hong Kong is useful.

SETTING: The tuberculosis programme of the Hong Kong Government Tuberculosis and Chest Service. OBJECTIVE: To determine the outcome of examination of household contacts in Hong Kong. DESIGN: A retrospective cohort study of all household contacts of 970 randomly selected index cases from a total of 5757 registered for treatment with the Chest Service. RESULTS: Of 2678 household contacts (three/index case) identified, 90% were examined; 41 active cases were found, at a rate of 1720/100000 (95%CI 1238-2329). The rate was highest among two extremes of age, 3604/100000 (95%CI 990-3615) in children < or = 5 years and 3347/100000 (95%CI 1456-6489) in those >60 years of age. Contacts of index cases whose sputum smear and culture were positive had the highest rate of disease, 2904/100000 (95%CI 1669-4673); but contacts with negative bacteriology also had a high rate of 1478/100000 (95%CI 678-2789). Active cases identified through contact tracing could be source cases rather than secondary cases. Eight per cent of children aged < or = 5 years had positive tuberculin reactions; as BCG vaccination is given to all newborns, with 99% coverage in Hong Kong in the past 30 years, it was difficult to estimate the rate of infection in these children. CONCLUSION: In Hong Kong, an area with an intermediate burden of tuberculosis, contact investigation is a very useful procedure for active case finding.     

Determinants of tuberculin sensitivity in a child population covered by mass BCG vaccination.

A cross-sectional survey of 701 Indian children aged 1-15 in five northern Canadian communities showed that 82% had a documented history of BCG vaccination while only 78% had a visible scar. The prevalence of 5 mm or more induration on Mantoux testing varied from 6 to 26%. Multiple logistic regression indicated that community, age, past use of isoniazid and time since the last Mantoux test were positive predictors of sensitivity. The presence of a BCG scar and the number of past vaccinations were not significantly associated but the elapsed time since the last BCG was negatively associated with a positive reaction. Overcrowding, nutritional status and past history of household and community contact with an active case of tuberculosis were also investigated but their independent effect could not be demonstrated. Despite the presence of mass BCG vaccination in this population, tuberculin testing is still a useful tool in assessing the risk of infection.     

Isoniazid resistant tuberculosis in a school outbreak: the protective effect of BCG

An outbreak of isoniazid resistant tuberculosis occurred in a large second level school. A total of 1,160 teenage pupils were at risk. Nineteen cases of tuberculosis were diagnosed, 15 were students, 9 of whom were among 251 non-vaccinated students and 6 among 909 vaccinated students. Two cases of miliary tuberculosis, one of whom also had tuberculous (TB) meningitis, occurred in the non-vaccinated group. The number of children with Heaf grade +3 or +4 was significantly greater among children who had been given Bacille Calmette-Guérin (BCG) vaccination (8 vs 4.4%). This suggests a boosting effect on the response in vaccinated children. The protective effect of neonatal BCG vaccination in this school outbreak suggests that it provides significant protection against tuberculosis lasting into adolescence.     

Is the BCG test of diagnostic value in tuberculosis?

Setting: In developing countries including Turkey, tuberculosis is still a major problem. Rapid diagnosis and early medical intervention are the two most important considerations in preventing the spread of the disease.Objective: This study was carried out to determine the diagnostic value of BCG test in childhood tuberculosis and compare it with tuberculin test in this regard.Design: 50 patients and 20 healthy children without any evidence of previous BCG vaccination and aged 80 days-15 years were simultaneously tested with purified protein derivative (PPD) and BCG vaccine.Results: In pulmonary tuberculosis BCG test was positive in 100% of cases and the PPD test in 44.5%. Similarly, BCG test was positive in 100% of miliary tuberculosis and tuberculous meningitis cases but PPD test was negative in all of them. Out of 22 patients with malnutrition 18 (82%) had positive BCG test and 4 had positive PPD test. BCG test showed uniformly high positivity in all grades of malnutrition.Conclusion: BCG is more reliable and sensitive than the tuberculin test in the diagnosis of tuberculosis. It is still valuable in the diagnosis of tuberculosis especially in developing countries where the disease is still a major public health problem and where sophisticated methods such as rapid culture with BACTEC and demonstration of bacilli with DNA probes are not widely available.     

Analysis on the epidemiological characteristics of pulmonary tuberculosis among children aged 0-14 in Sichuan Province from 2009 to 2018

目的 分析四川省0~14岁儿童肺结核流行特征,掌握流行变化趋势,为加强儿童肺结核防控工作提供依据。 方法 基于《中国疾病预防控制信息系统》子系统《传染病报告信息管理系统》及其基本信息项目中报告的四川省2009—2018年0~14岁儿童肺结核患者的报告发病数据和人口数据,利用Joinpoint回归模型进行趋势性分析。结果 2009—2018年,四川省共报告0~14岁儿童肺结核10981例,占全人口肺结核报告发病例数的1.79%(10981/612506),10年间儿童肺结核实际报告发病率从2009年的8.91/10万(1349/15140100)上升至2018年的9.35/10万(1229/13141100),年均增长率为0.50%;Joinpoint回归分析显示,儿童肺结核标准化报告发病率在2009—2015年[年度变化百分比(annual percent change,APC)=-1.98%,P=0.196]、2015—2018年间(APC=10.13%,P=0.061)呈现阶段性变化,但均趋于稳定。0~14岁男童肺结核报告发病6011例,平均报告发病率为8.43/10万(6011/71339600),女童报告发病4970例,平均报告发病率为7.64/10万(4970/65071300),男童肺结核报告发病率普遍高于女童(χ²=26.261,P<0.001)。不同年龄组中,各组报告发病率的差异有统计学意义(χ²=3629.827,P<0.001),0~岁组(9.08/10万,774/8523100)和10~14岁组(14.37/10万,6575/45769900)儿童肺结核报告发病率普遍高于1~岁组(4.09/10万,1423/34833900)和5~岁组(4.67/10万,2209/47284100)报告发病率;Joinpoint回归分析显示,0~岁组儿童肺结核报告发病率从2009年的13.32/10万(132/991000)快速下降至2018年的3.73/10万(31/831900)(APC=-10.80%,P=0.002),10~14岁组儿童肺结核报告发病率2016年以后呈快速上升趋势,由13.39/10万(760/5676700)上升至18.88/10万(786/4162100)(APC=17.99%,P=0.042)。结论 近年来四川省儿童肺结核报告发病率整体趋于稳定,但仍有上升趋势,需要继续加强新生儿卡介苗接种、学生结核病防控、家庭内肺结核患者儿童密切接触者筛查工作。     

Tuberculin reactivity in a chest clinic: the effects of age and prior BCG vaccination

Heaf tests were performed in 834 adults and children seen during one year in a tuberculosis contact clinic in Edinburgh. All subjects with a past history of tuberculosis, or who subsequently developed evidence of tuberculous infection and 63 subjects of Asian origin were excluded to leave 749 'healthy' adults and children broadly representative of the local caucasian population. All Heaf tests in 178 children without BCG vaccination were negative or grade I whereas 16 (73%) of the 22 children with a history of previous BCG vaccination were positive grade I or II. A strongly positive Heaf test (grade III-IV) in any child with or without previous BCG vaccination seen as a tuberculosis contact implies recent infection and merits consideration for chemoprophylaxis or prolonged follow-up. Two hundred and seventy adults without previous BCG vaccination showed an increasing incidence of strongly positive Heaf tests (grade III or IV) with age reaching a peak of 55% in the 45-65 age group; beyond the age of 65 this fell to 37%. Two hundred and eighty-one adults with previous BCG vaccination showed significantly more Heaf grades I and II, fewer negatives and fewer strong positives than the unvaccinated group. A strongly positive Heaf test (III-IV) is a frequent finding in a healthy adult and has little discriminatory value in the diagnosis of active tuberculosis infection in Edinburgh, and by implication elsewhere in the United Kingdom. Positive tuberculin tests should be viewed in the context of the tuberculin profile of the local population.     

Retrospective assessment of the effectiveness of BCG vaccination by multiple puncture method (Kuchiki's needle) in childhood tuberculosis

The retrospective assessment of the effectiveness of BCG vaccination by multiple puncture method (Kuchiki's needle) was examined in childhood tuberculosis patients treated at our hospital. They were 137 children aged 0 month to 15 years. Seventy-nine of them were vaccinated with BCG and 58 of them were not vaccinated. Forty-seven patients had been vaccinated at 3 to 4 months after birth, and excluding 2 cases who were revaccinated thereafter the remaining 45 patients were compared with unvaccinated 58 patients. Following results were obtained. 1. Vaccinated 45 patients. 1) Within 3 months after the vaccination, 6 children showed breakdown of tuberculosis. Two of them were miliary tuberculosis. Three patients were positive bacteriologic findings. They were supposed to be infected before BCG vaccination or before the appearance of immunity by BCG vaccination. 2) From 4 months to 2 years after the vaccination, 12 children showed breakdown of tuberculosis, but they were all mild type and all of them were negative bacteriologic findings. 3) After 2 years or more from the vaccination, 27 children showed breakdown of tuberculosis. Three of them were positive bacteriologic findings. 2. Unvaccinated 58 patients. 1) Thirty-seven patients, aged 0 month to 2 years and 4 months, showed breakdown of tuberculosis. Seventeen patients were positive bacteriologic findings. Three cases of tuberculous meningitis (2 of them died) and 2 cases of miliary tuberculosis were observed. Paratracheal lymph node swelling was recognized in 5 cases, and bronchial stenosis due to compression was seen in 4 cases (one of them died). 2) Twenty-one patients were more than 2 years and 5 months old. Eight of them were positive bacteriologic findings.(ABSTRACT TRUNCATED AT 250 WORDS)     

The frequency profile of tuberculin skin testing among students in nursing school]

The frequency profile of tuberculin skin testing (TST) among students in nursing school was studied. Students received a TST upon matriculation. The TST was done by the method of Mantoux, in which 0.1 ml of PPDs was administered intradermally, and the diameters of skin rash and induration were read by the medical doctor at 48 hours. When TST results are negative--that is, the diameter of skin rash is below 10 mm (in Japan, the TST results are judged by skin rash diameter rather than that of induration)-BCG vaccination is given. Those receiving the BCG vaccination are retested with a TST one year later. When the second TST was also negative both the BCG vaccination and TST were followed for two more years. Those students testing TST-negative are not permitted to take clinical training in the tuberculosis ward. Student's mean age on entrance was 18.6 +/- 2.1 years old, and all but three were female. About 70% of students entering in 1996 to 1998 had a history of previous BCG vaccination. In 14% their positive TSTs could be attributed to probable infection with tuberculosis in childhood. In the remaining 16%, details as to TST and BCG vaccination status are unknown. The frequency distribution of TST results was bimodal, showing one peak at 6 mm and another at 12 mm (skin rash diameter). The percentage of negative and positive reactors are 47.1% and 52.9%, respectively. The TST-negative students entering in 1994 to 1996 were given the BCG vaccination. Twenty-four of 134 students (17.9%) remained negative at the second TST, and 6 students (4.5%) at the third year, even after two repeated BCG vaccinations. The TST results were chronologically observed in the above 6 students after BCG vaccination. The TST results of two students showed positive in September, 1996 and June, 1997. While four students showed positive in September, 1996, all ultimately reverted to negative when retested in June, 1997. Those students had negative results for TST at the initial test in 1998 had the two step-tuberculin skin testing. All eight students with negative TST had the history of BCG vaccination. The second TST showed positive except one student whose scar after BCG vaccination was not observed on the arm. The TST is currently recommended in hospital tuberculosis-control programs. If TST-negative, medical staff and students may not work in the tuberculosis ward. However, after BCG vaccinations is given, and subsequent TST conversion is confirmed, they are then able to work or to have training in the ward. From our results, there is 4.5% non-convertors even after 2 years of repeated BCG vaccinations. However, these non-converters turned positive four months after BCG vaccination, only to revert to negative nine months later. These students are considered to have delayed hypersensitivity to PPD after BCG vaccination. However, their reactivity waned in the short period of nine months after the conversion of their TST's. Therefore, it is concluded that non converters after repeated BCG vaccinations are able to have clinical training in the tuberculosis ward as long as their BCG vaccinations are correctly administered and any immunological deficiencies are ruled out.