Bacillus Calmette-Guerin vaccination in preterm infants.

OBJECTIVE: To evaluate the tuberculin response after bacille Calmette-Guérin (BCG) vaccination in preterm infants. METHODS: Thirty-five infants born at <35 weeks gestation were included in the study. An intradermal injection of 0.05 ml BCG vaccine was given to each infant at postnatal months 2-3. Tuberculin skin tests (TSTs) were done 8-12 weeks after vaccination using 0.1 ml of 5 TU purified protein derivative (PPD). The diameter of induration was measured 72 h later and > or =5 mm induration was taken as a positive response. RESULTS: The babies had a mean birth weight (SD) of 1650 (424) g, and a gestational age of 32.4 (2.1) weeks. The TST was positive in 20 (57%) of the infants. The mean body weight of the tuberculin-positive babies was significantly higher than the others at both vaccination and TST. No difference was found between groups concerning sex, birth weight, gestational age, intrauterine growth and postnatal age at BCG vaccination and TST. CONCLUSION: BCG vaccination in preterm infants at months 2-3 of postnatal life results in a high percentage of BCG scarring and 57% TST conversion. A positive tuberculin response was significantly related to the postnatal weight gain of the preterm infants.     

北京市新生儿卡介苗接种质量的监测

目的　了解近10年来北京市新生儿卡介苗接种工作的质量情况。方法 对1991～2000年本市各年新生儿卡介苗接种工作记录和质量监控结果记录进行统计,逐年分析。结果 近10年全市新生儿卡介苗接种率(简称接种率)、接种及时率、接种后12周结素试验阳转率(简称阳转率)和卡痕率以及结素反应平均直径、卡痕平均直径等6项指标均比较稳定。城区、近郊区和远郊区的接种率无明显差别,均在97%以上;农村的阳转率和结素反应平均直径两项指标也非常接近城区(包括近郊区)。结论 北京市新生儿卡介苗接种工作质量较高并在近10年中保持了各项监测指标的稳定。     

Comparative skin testing with PPD tuberculin,Mycobacterium avium and M. scrofulaceum sensitin in schoolchildren in Saudi Arabia

Setting: Jizan region, Saudi Arabia.Objective: To test methodology for studies of tuberculin sensitivity and effectiveness of BCG vaccination programme.Design: School children (n = 315) aged 6–12 years simultaneously tested intradermally with PPD tuberculin RT23, 2TU and 0.1 μg Mycobacterium avium or M. scrofulaceum sensitin. Presence of BCG scar as evidence of previous BCG vaccination. Cervical lymph nodes palpated.Results: BCG coverage was 75%. The prevalences of positive reactions (induration ⪰ 6mm) were higher among children with than without scar. Prevalences of positive reactions to PPD and M. scrofulaceum sensitin were higher among girls than boys. In children with scar, the mean size of positive reactions to PPD was larger among girls than boys, and the prevalence of positive reactions was smaller in this group among children with than without palpable cervical lymph nodes. The sizes of reactions both to M. avium and to M. scrofulaceum sensitin were correlated to the size of the tuberculin reactions. Previous admission to hospital was reported less often by children with than without scar.Conclusions: The technique applied and training of staff was satisfactory. In further studies, however, we will apply three simultaneous tests to each person.     

Safety and immunogenicity of Bacillus Calmette-Guerin vaccine in children born to HIV-1 infected women

This prospective cohort study was conducted to determine the complication of Bacillus Calmette-Guerin (BCG) vaccination given to newborn infants born to HIV-1 seropositive mothers and to compare the tuberculin reaction 9 months after BCG vaccination between HIV-1 infected and non infected children. Two hundred and twenty-three infants with BCG immunization at birth were examined. No BCG complication was noted. Tuberculin skin tests were performed on 126 children (56.5%). Eleven of them were excluded because of failure to have skin tests read at 48 hours. Of the 115 infants enrolled to this study, 15 (13%) had no BCG scar and 50 (43.5%) had no tuberculin reaction. Twenty-six children were classified as group 1 or HIV-1 infected children and 89 children were group 2 or HIV-1 non infected. Group 1 children had a smaller tuberculin skin response (X+SD) than group 2 (1.15 +/- 2.82 vs 4.64 +/- 4.29 mm; p < 0.0001). Mean weight + SD of group 1 children was also significantly less than those in group 2 (8,013 +/- 741 vs 8,540 +/- 984 g; p < 0.05). The proportion of children with non reactivity to the tuberculin test, a negative tuberculin test and no BCG scar in group 1 was significantly higher than that in group 2 (76.9% vs 33.7%, 92.3% vs 52.8% and 36.4% vs 6.7% respectively; p < 0.0001 for all). But, the proportion of non reactivity to the tuberculin test in children with or without BCG scar of each group was not different (p > 0.05). Positive tuberculin tests were 7.7% and 47.2% in group 1 and 2 respectively. None of the children with positive tuberculin tests had clinical evidence of tuberculosis. The findings of this study indicate that BCG vaccine given to newborn infants of HIV-1 seropositive mothers is safe. Although tuberculin skin responses of HIV-1 infected children are less than those of HIV-1 non-infected children, it is possible that BCG vaccine might protect these children from developing severe tuberculosis.     

Annual risk of tuberculous infection in Khammam a tribal district of Andhra Pradesh

A tuberculin survey to estimate annual risk of tuberculosis was conducted in Khammam tribal district during 2001-2002. A total of 8637 children were test-read--2991 without BCG scar and 5442 with BCG scar. The tests were performed using ITU PPD RT23 and the maximum size of induration was recorded at about 72 hours after the test. Based on the frequency distribution of reaction size, cut-off point for infection with tubercle bacilli was considered at 12 mm. Using this criterion, the prevalence of infection was estimated at 11.8% among children without BCG scar and 10.6% among children with BCG scar. This difference was found to be statistically insignificant. ARTI rates computed from the prevalence estimates among children without and with BCG scar were 1.6% and 1.5% respectively. It was computed as 1.5% from the prevalence in the combined group i.e. irrespective of BCG scar status.     

The influence of Calmette-Guérin bacillus immunization on the booster effect of tuberculin testing in healthy young adults

The booster or enhancement effect of repeated tuberculin skin testing in Calmette-Guérin bacillus (BCG)-vaccinated young adults was studied in 208 first-year medical, nursing, and medical technology students in Santiago, Chile, where BCG vaccine is usually administered at birth and at 6 and 14 yr of age. Thirty-three students had no BCG scar, 62 had one scar, 71 had two scars, and 42 had three scars. The mean age for each group was 19 yr. All students were healthy and had no known exposure to tuberculosis or history of tuberculosis or other mycobacterioses. The size in millimeters of induration of the first tuberculin reaction (PPD1) was clearly correlated with the number of BCG scars: 2.3 +/- 4.6 for no scars; 6.7 +/- 6.7 for one scar; 10.9 +/- 5.9 for two scars, and 13.2 +/- 5.3 for three scars. The second tuberculin reaction (PPD2), performed 2 wk later on the contralateral forearm, showed a marked increase in reactivity. The increase in reaction size was most evident in students who had BCG scars but who were initially PPD negative (less than 10 mm). Smaller increases were observed in students without BCG scars, and also in those who had BCG scars but who were initially tuberculin positive (greater than or equal to 10 mm). The persistence of the booster effect was evaluated by performing PPD3 1 yr later. PPD1-negative students with BCG scars maintained the increased level of reactivity to PPD2 after 1 yr. An immunizing effect of tuberculin testing was suggested in 11 nonimmunized students who were initially PPD negative.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

Tuberculin skin testing: Determinants and reaction

Mantoux purified protein derivative (PPD) skin testing was performed in schoolchildren who were grouped according to positive (Group I, n = 205) and negative (Group II, n = 79) exposure to recent acid-fast bacilli (AFB) smear-positive tuberculosis (TB) family contact. A prospective case-control study was undertaken to evaluate whether repeat bacille Calmette-Guérin (BCG) vaccination, nutritional state, presence/absence of BCG scar, and degree of AFB positivity of sputum of adult TB cases affect PPD skin reactivity in these two groups. Group I with TB contacts had larger induration (13.00 +/- 11.29 mm) than the Group II control group of 4.52 +/- 6.20; P = 0.000. Purified protein derivative reaction as to the number of BCG vaccination(s) received showed an increase in size as the BCG vaccination is repeated with significantly larger induration in Group I than in Group II (P = 0.048). The nutritional status was subgrouped into A (weight < 10 percentile), B (weight 50-75 percentile), and C (weight > 90 percentile), which were comparable for both groups. The mean PPD induration of subgroup A in Groups I and II was not statistically different. However, the mean PPD induration was highly significant between Groups I and II in subgroup B (12.46 +/- 10.70 vs 3.80 +/- 5.71 mm; P = 0.000) and subgroup C (14.31 +/- 11.54 vs 5.42 +/- 6.70 mm; P = 0.000). Children in group I with the BCG scar were noted to have significantly greater PPD induration size than in group II (14.14 +/- 11.23 vs 5.05 +/- 6.24 mm; P = 0.000). The degree of AFB positivity of sputum of TB adult cases (1+ to 4+ and cavitary TB) has no effect on PPD size (P = 0.766). Close contact with individuals with active TB (AFB smear positive) is a very important factor for PPD skin conversion. Repeat BCG vaccination, malnutrition, and BCG with scars present difficulties in making a diagnosis of TB infection but did not affect PPD reactivity and did highlight the need for thorough clinical evaluation.     

Tuberculin reactivity and tuberculosis epidemiology in the Pakaanóva (Wari') Indians of Rond?nia, south-western Brazilian Amazon.

OBJECTIVE: To investigate the characteristics of tuberculin skin test reactivity in the Pakaanóva Indians, in Amazonia, Brazil, after revaccination of all study participants with bacille Calmette-Guerin (BCG). METHODS: The investigation was designed as a post-BCG vaccination purified protein derivative (PPD) survey. Data included PPD readings, age, sex, nutritional status, place of residence, previous tuberculosis, physical examinations and BCG status. Bivariate and multivariate logistic regression analyses were conducted. RESULTS: About 90% (n = 505) of the total population participated. One third (32.1%) of the subjects presented induration > or = 10 mm at 72 h. Induration sizes showed weak linear correlation with age; differences between sexes were not observed. Skin reaction was not associated with nutritional status. Individuals with a history of tuberculosis were six times more likely to test positive. History of tuberculosis, age, and previous BCG vaccination were significantly associated with PPD reactivity in the multivariate analyses. CONCLUSION: The Pakaanóva showed a high proportion (58.4%) of non-reactors, even with a recent BCG booster. Sex differences in PPD reactivity were either not present or could not be demonstrated. The association between age and PPD reactivity resembles that observed in other Amazonian populations. The authors discuss the potential of PPD testing as a screening tool to enhance tuberculosis detection, especially in indigenous populations in Amazonia with limited access to health services.     

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.     

Relationship between IFN-gamma and skin test responsiveness to Mycobacterium tuberculosis PPD in healthy, non-BCG-vaccinated young adults in Northern Malawi.

SETTING: Rural northern Malawi, where vaccination with BCG Glaxo (1077) provides protection against leprosy but not against pulmonary tuberculosis. OBJECTIVE: To evaluate the patterns of responsiveness to purified protein derivative of Mycobacterium tuberculosis (PPD) in terms of delayed type hypersensitivity (DTH) and interferon-gamma (IFN-gamma) production. DESIGN: IFN-gamma was measured in 6 day whole blood cultures diluted 1 in 10, stimulated with PPD RT48, and the results compared to the DTH response to PPD RT23. A total of 633 individuals aged 12 to 28 years, without prior BCG vaccination, were recruited. RESULTS: Overall, 63% of subjects made a positive IFN-gamma response (defined as >62 pg/ml), and 37% gave a DTH induration of >5 mm. A strong correlation between skin test and IFN-gamma responses was observed, although with interesting exceptions: 13/270 individuals with zero DTH showed IFN-gamma responses >500 pg/ml, and 7/53 individuals with >10 mm induration showed IFN-gamma responses < or = 62 pg/ml. The prevalence of skin test responsiveness increased with age, and was higher among older males than females; age-sex patterns were less clear for IFN-gamma production. CONCLUSION: The 6 day IFN-gamma response to PPD correlates well with Mantoux skin test induration. The discordant individuals may represent important subsets in terms of protective immunity and risk of clinical tuberculosis.     

四所中学初中生结核菌素反应性调查

目的了解当地初中生结核菌素反应状况。方法选医院驻地怀来县4所中学5153名初一年级学生进行标准化PPD试验调查，并对学生年龄、性别、居住来源及结核病流行特点进行调查分析。结果80.2%的学生集中在13～14岁组，来源于农村者占57.6%，≥5mm总阳性反应率23.1%，≥15mm为7.4%。2219名无卡痕学生PPD反应在≥5mm，≥10mm，≥15mm和≥20mm分别为16.0%、10.9%、5.9%和2.9%，有卡痕学生结素反应性明显高于无卡痕者；有结核接触史和既往史学生的结素反应均高于无结核接触史和既往史者。结论把初中新入学学生作为当地结素试验对象，建议将≥15mm结素反应者列为预防性治疗对象,以减少结核病发生。     

QuantiFERON-TB Gold test for screening latent tuberculosis infection in hemodialysis patients

Hemodialysis patients are at increased risk of latent tuberculosis infection (LTBI) compared with the general population. QuantiFERON-TB Gold (QFT-G) for LTBI detection is more promising than tuberculin skin test (TST) in hemodialysis patients. The aim of this study is to determine whether the QFT-G is more sensitive than the TST in hemodialysis patients in LTBI. Eighty nine hemodialysis patients were evaluated for latent tuberculosis infection with the TST and QFT-G. Blood was obtained for QFT-G, and then TST was administered to all patients. Demographic information, laboratory tests, chest radiography results and BCG vaccination status were collected on standardized patient medical files. Forty patients had positive QFT-G results. 56 patients had TST induration above 5 mm, 28 patients above 10 mm. 61 patients had BCG vaccination scar. Statistically significant correlation was detected between TST and QFT-G (p< 0.05). In the BCG non-vaccinated subgroup, TST was positive in 8 (29%) patients and the QFT-G was positive in 11 (39%). Among the 21 non vaccinated patients with results for both tests, the concordance between the TST and QFT-G was 82%, k= 0.61, p= 0.001. We found good agreement between the TST and QFT-G test for LTBI in non vaccinated hemodialysis patients, whereas we found poor agreement in vaccinated patients. Because BCG vaccination is widely used in our country, the QFT-G test might be more useful for the diagnosis of LTBI than TST in hemodialysis patients who are suspected to have LTBI.     

The annual risk of tuberculous infection in the eastern zone of India.

SETTING: Rural and urban areas of eight selected districts in the eastern zone of India. OBJECTIVES: To estimate the annual risk of tuberculous infection (ARTI). STUDY DESIGN: A community-based, cross-sectional tuberculin survey was conducted among children aged 1-9 years residing in a sample of rural and urban areas. Stratified two-stage cluster sampling was adopted for selection of rural and urban clusters. A total of 40964 children in 515 clusters underwent tuberculin testing and reading with 1TU PPD RT23 with Tween 80; the maximum transverse diameter of induration was measured about 72 h after the test. RESULTS: A bacille Calmette-Gúerin (BCG) scar was observed in 51.5% of the test-read children. The frequency distribution of tuberculin reaction size among 19332 children without BCG scar was found to be bimodal, with the mode of reactions attributable to infection with tubercle bacilli at 20 mm. The prevalence of infection was estimated as 6.9%. The ARTI computed from the estimated prevalence was 1.3%. Children residing in the urban areas were found to be at a significantly higher risk of infection than those residing in rural areas. CONCLUSION: The high rate of ARTI in the eastern zone of India suggests a need for committed, sustained action in provision of quality tuberculosis control services.     

Annual risk of tuberculous infection in the western zone of India.

SETTING: Rural and urban areas of six selected districts in the western zone of India. OBJECTIVES: To estimate the annual risk of tuberculous infection (ARI). DESIGN: A community-based, cross-sectional tuberculin survey was conducted among children aged 1-9 years residing in a sample of rural and urban areas of six districts in the western zone of India. Stratified two-stage cluster sampling was adopted for selection of rural and urban clusters. A total of 48473 children in 600 clusters underwent tuberculin testing with 1TU PPD RT23 with Tween 80; the induration was measured about 72 h after the test. RESULTS: The BCG scar was observed in 52% of the test-read children. Estimation of the prevalence of infection was based on the frequency distribution of tuberculin reaction size among 22259 children without BCG scar. Reactions > or = 15 mm were considered attributable to infection with tubercle bacilli. The prevalence of infection was estimated to be 9.3%, and the ARI computed from the estimated prevalence was 1.8%. The proportion of infected children was found to be significantly higher in urban than in rural areas. CONCLUSION: The high rate of ARI in the western zone of India calls for further intensification of tuberculosis control efforts.     

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.     

Revaccination with BCG: its effects on skin tests in Kuwaiti senior school children

Following a policy of BCG vaccination adopted in Kuwait more than 20 yrs ago, children receive their first vaccination just before starting school. Those who have a response of less than 10 mm induration to 2 tu of RT23 PPD, when they are 13 yrs old, are revaccinated. The effects of this revaccination on skin test positivity in a group of 18 yr old senior school children have been investigated. In a random study group 23% were found to have received BCG a second time. Revaccination resulted in a significant increase in positivity to tuberculin, and to the other 6 reagents tested, that was much more than would have been expected due to the passage of time alone in low responders. Scars of the second BCG vaccination were larger than those after the first vaccination, and showed a sex difference, with scars being significantly larger in boys than in girls. Boys also tended to show the largest responses to skin tests, with the notable exception of tuberculin to which girls showed the largest response. In most cases responses to skin tests were larger after revaccination than after a single vaccination. Based on this study, it is impossible to be sure that revaccination improved protective immunity, but the increase in tuberculin responsiveness, and recognition of environmental mycobacterial species may be indirect evidence supporting this conclusion.     

BCG—PPD与TB—PPD皮肤试验在大学生结核病筛查中的差异性分析

目的 比较卡介菌纯蛋白衍生物（purified protein derivative of BCG,BCG-PPD）与结核菌素纯蛋白衍生物（purified protein derivative of tuberculin,TB-PPD）在大学生结核病筛查中的差异。 方法 回顾性分析2012—2013年北京市西城区3所大学2821名学生的结核病筛查数据。根据使用的PPD试剂种类进行分组,BCG-PPD组学生1386名;TB-PPD组学生1435名。对两组观察者分别进行结核菌素试验,72 h查验硬结平均直径,对强阳性者进行胸部X线检查。采用SPSS 11.5软件进行统计分析,用秩和检验对两组硬结平均直径进行比较,用χ^2检验对组间PPD结果分布频度及结核病筛查结果进行比较,当理论值＜1时,采用Fisher确切概率法,卡痕与PPD阳性结果间相关性分析采用logistic回归,P〈0.05为差异有统计学意义。结果 中位硬结平均直径BCG-PPD组（6 mm）大于TB-PPD组（0 mm）,差异有统计学意义（Z=－10.034, P〈0.05）。BCG-PPD组的阳性率（54.8%, 759/1386）明显高于TB-PPD组（32.7%,469/1435）（χ^2=139.818,P〈0.05）;PPD强阳性率BCG-PPD组为6.6%（92/1386）,高于TB-PPD组的3.4%（49/1435）（χ^2=15.425,P〈0.05）;BCG-PPD组的异常反应发生率为1.9%（27/1386）,高于TB-PPD组的0.4%（6/1435）,差异有统计学意义（χ^2=14.274,P〈0.05）。卡痕与PPD阳性结果相关,有卡痕者更容易出现PPD阳性结果（OR=2.046,95％CI=1.630～2.569,P〈0.05）。 结论 TB-PPD和BCG-PPD皮肤试验在大学生结核病筛查中的强阳性率和异常反应发生率上存在差别,有进一步探讨的必要。     

Absence of relationships between tuberculin responses and development of adult asthma with rhinitis and atopy

OBJECTIVE: To investigate the relationship between tuberculin skin responses and the development of adult asthma, rhinitis, and atopy. METHODS: Two hundred fourteen patients with mild-to-moderate asthma accompanied with rhinitis and 220 normal volunteers underwent a medical history, chest radiography, allergen skin-prick testing (SPT), bovine Mycobacterium tuberculosis vaccine (BCG) scar identification, purified protein derivative (PPD) tuberculin skin testing, serum-total and serum-specific IgE measurements, and bronchial provocation (provocative dose of histamine causing a 20% fall in FEV(1) [PD(20)]). RESULTS: Thirty-one normal volunteers (14.1%) and 168 asthma-rhinitis subjects (78.5%) had one or more positive skin test results (p < 0.0001). Neither the presence of a BCG scar nor a history of BCG vaccination had a significant effect on atopy in either group. The rate of PPD positivity had no statistical difference between atopy and nonatopy in both groups. In multivariate logistic regression analysis, the odds ratio for tuberculin reactivity was not related to the level of serum-total IgE nor to the level of serum-specific IgE to Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF), skin response to DP and DF, and PD(20). Overall, no significant correlations were found between tuberculin skin reactivity and log serum-total IgE or PD(20). CONCLUSION: There is no relationship between history of tuberculosis infection, tuberculin responses, and development of adult bronchial asthma, allergic rhinitis, and atopy. Our study suggests that the protection provided by intradermal BCG vaccination in infants to prevent atopic diseases may be limited in early childhood, when a substantial memory of cellular immune modulation still exists.     

Enhancement of vitamin A combined vitamin D supplementation on immune response to Bacille Calmette-Guérin vaccine revaccinated in Chinese infants

ObjectiveTo investigate whether there is an association between diameter of bacille Calmette-Guérin (BCG) scars and effect of purified protein derivative (PPD) reaction and to determine whether vitamin A (VA) combined vitamin D (VD) supplementation influences the immune response to BCG revaccinated in Chinese infants.MethodsA cross-section and 3-month community-randomised trial was conducted. A total of 5 629 infants at 3, 6 and 12 months of age in Junan County of China were examined for BCG scar formation. Then, 597 revaccinated infants were randomly assigned to supplementation (n=307) and control (n=290) groups. The supplementation group were daily assigned to 1 500 IU VA and 500 IU VD for 3 months. Then all infants were subjected to skin test with PPD.ResultsThe diameter of BCG scars was positively correlated with diameter of skin indurations of PPD (r=0.17, P<0.05) in the 5 629 infants. The rate of positive response to PPD was higher in the supplementation group than in the control group (96.1% versus 89.7%, P<0.05, prevalence ratio 1.07, 95% CI 1.02-1.12). The prevalence ratio of PPD response for the supplementation group compared with that for the control group was 1.07 (95% CI 1.01-1.13) for the males and 1.08 (95% CI 1.00-1.17) for the females. For the supplementation group, the males got larger tuberculin induration than the females [(0.73±0.21) cm versus (0.67±0.20) cm, P<0.05) after intervention.ConclusionsThe diameter of BCG scars was effectively correlated with PPD response, which indicates BCG scar formation may be an useful tool to evaluate the effect of tuberculosis prevention. VA combined VD supplementation may play an immuno-regulatory role in BCG revaccination. This may contribute to the prevention of childhood tuberculosis.