Search

Setting: The association between smoking and pulmonary tuberculosis has not often been studied., Objective: To assess the influence of cigarette smoking on the development of active pulmonary tuberculosis in young people who were close contacts of new cases of smear-positive pulmonary tuberculosis., Design: A case-control study in which 46 'cases' (patients with active pulmonary tuberculosis: isolation of Mycobacterium tuberculosis or clinical and/or radiographic evidence of current pulmonary tuberculosis, with a positive tuberculin skin test) and 46 'controls' (persons with positive tuberculin reaction, negative bacteriological test and without clinical and/or radiological evidence of pulmonary tuberculosis) were included. Smoking habits were investigated by questionnaire. Univariate and multivariate analysis was performed, and odds ratio (OR) was adjusted for age, gender and socio-economic status., Results: Statistically significant differences were found in active smokers (occasional and daily smokers) (OR: 3.65; 95% CI, 1.46 and 9.21; P < 0.01), daily smokers (OR: 3.53; 95% CI, 1.34 and 9.26; P < 0.05), and individuals who were both passive and active smokers (OR: 5.10; 95% CI, 1.97 and 13.22; P < 0.01) and passive and daily smokers (OR: 5.59; 95% CI, 2.07 and 15.10; P < 0.001). There was a dose-response relationship between the number of cigarettes smoked daily and the risk of active pulmonary tuberculosis., Conclusions: The data studied show that cigarette smoking is a risk factor for pulmonary tuberculosis in young people, with a dose-response relationship with the number of cigarettes consumed daily.

It has been established that HLA antigens are susceptibility factors for different cancers, including thyroid tumors. However, the diversity and sometimes weak and contradictory associations found have frequently led to the view that the HLA and tumorigenesis links might be the result of statistical errors. However, it has recently been established that it is indeed a currently complex and unexplained but real phenomenon, which may be crucial in preventing several types of cancer. In the present work we have found in a relatively large series of thyroid cancer patients (n = 161) that both HLA class I (B35) and class II (DR11) antigens are susceptibility factors only in the papillary tumor group of patients, B35 association p value is found at the limit of significance (pc(120) = 0.05); the follicular group did not show any HLA association, suggesting that the etiopathogenesis of each type of cancer is different. HLA-B35 and DR11 are not working together to induce tumorigenesis and each of them seems to confer susceptibility by using different pathways or by being markers of distinct neighboring susceptibility genes. DR4 has also been found in 86% (n = 6) of Hürthle cell carcinoma. No association has been found between HLA and disease activity. HLA mechanisms of association to cancer are discussed and a world-wide HLA/tumorigenic study is proposed to obtain a clear picture of the puzzling and controversial susceptibility markers found in different tumors and in different ethnic groups.

Background: The aim of this study was to know the efficacy of the BCG vaccination campaign of the newborns of Barcelona carried out during the period from 1966-1974., Methods: To achieve this aim an epidemiologic investigation was undertaken by an observational analytical study of paired cases and controls. Two hundred and fifty randomly selected cases were studied between 1978-1988 from between 4-21 years of age during the study period. The cases were paired with 750 controls (1:3) with identical conditions and age, sex and place of residence. Statistical analysis of data was performed by the specific methods for this type of study., Results: The estimated gross odds ratio was 0.68; the interval of confidence 95% and 0.51-0.91 (p < 0.025). The efficacy of this vaccination campaign was estimated as weak at 32%, in the age group and investigation time being greater in males and diminished with time. The percentage of new cases of tuberculosis potentially prevented by this campaign was calculated at 13%., Conclusions: The weak efficacy of the BCG vaccination campaign may be attributed not only to the unforeseen effects of this vaccine but also to the deficient operative aspects of the campaign itself.

Background: The aim of this study was to know whether the human reaction to the Mantoux test with 5 UT of PPD RT 23 is similar to that achieved with the same test but with 2 UT of the same substance., Methods: A simultaneous double Mantoux test was used at doses of 2 UT and another of 5 UT of the same trade mark of tuberculin PPD RT 23 with Tween 80 in 2,575 individuals. The subjects were distributed into two different groups of different ages, taking into consideration the possible presence of BCG vaccination., Results: The doses of 5 UT produced a greater number of tuberculin positive individuals and a greater diameter of induration of reaction than that of the doses of 2 UT in both groups and with significant statistical differences. One hundred ninety-six (7%) subjects were tuberculin positive with 5 UT and negative with 2 UT., Conclusions: The reactions produced by the Mantoux test with 5 and 5 UT PPD RT were different since the two doses are not bioequivalent.