Background: The accurate diagnosis of latent tuberculosis infection (LTBI) is an important component of any tuberculosis control programme and depends largely on tuberculin skin testing. The appropriate interpretation of skin test results requires knowledge of the possible confounding factors such as previous BCG vaccination. Uncertainty about the effect of BCG vaccination on tuberculin skin testing and the strength with which recommendations are made to individual patients regarding treatment of LTBI have identified a need to analyse the available data on the effect of BCG on skin testing. A meta-analysis of the evidence for the effect of BCG vaccination on tuberculin skin testing in subjects without active tuberculosis was therefore performed. Methods: Medline was searched for English language articles published from 1966 to 1999 using the key words "BCG vaccine", "tuberculin test/PPD", and "skin testing". Bibliographies of relevant articles were reviewed for additional studies that may have been missed in the Medline search. Articles were considered for inclusion in the meta-analysis if they had recorded tuberculin skin test results in subjects who had received BCG vaccination more than 5 years previously and had a concurrent control group. Only prospective studies were considered. The geographical location, number of participants, type of BCG vaccine used, type of tuberculin skin test performed, and the results of the tuberculin skin test were extracted. Results: The abstracts and titles of 980 articles were identified, 370 full text articles were reviewed, and 26 articles were included in the final analysis. Patients who had received BCG vaccination were more likely to have a positive skin test (5 TU PPD: relative risk (RR) 2.12 (95% confidence interval (CI)1.50 to 3.00); 2 TU RT23: 26.50 (95% CI 1.83 to 3.85). The effect of BCG vaccination on PPD skin test results was less after 15 years. Positive skin tests with indurations of >15 mm are more likely to be the result of tuberculous infection than of BCG vaccination. Conclusions: In subjects without active tuberculosis, immunisation with BCG significantly increases the likelihood of a positive tuberculin skin test. The interpretation of the skin test therefore needs to be made in the individual clinical context and with evaluation of other risk factors for infection. The size of the induration should also be considered when making recommendations for treatment of latent infection.
Background To study the prevalence of genital chlamydia and gonococcal infections in women at risk of acquiring sexually transmitted infections in the Kumasi metropolis, Ghana. Methods Structured interviews and clinical examination of participants aged between 18 and 35 years (inclusive) were carried out. Other inclusive criteria were having at least three sexual acts per week and having had at least two sexual partners in the preceding 3 months. Vaginal swabs were also obtained to test for gonorrhoea and chlamydia infections. Results One thousand and seventy women participated in the study. Genital chlamydia infection was found in 4.8% of participants whilst gonococcal infection was found in 0.9% of participants. Conclusion The prevalence of genital chlamydia and gonococcal infections was low in these at-risk women. The prevalence is also lower than reported in other female populations in the country.
OBJECTIVE:To compare cases of tuberculosis (TB) diagnosed among aboriginal persons with a random sample of nonaboriginal persons diagnosed with TB, and evaluate the trends in rates of disease between both groups during the same period. DESIGN: A case-control study. SETTING: A provincial TB control program. PATIENTS AND METHODS: All patients with TB diagnosed among aboriginal persons in British Columbia between 1992 and 1996 were compared with control patients diagnosed during the same period. For each patient a control patient was identified. INTERVENTION:The demographic details, type of disease, bacteriology, risk factors for TB, therapy received as well as mode of administration were documented. The number of contacts identified for each patient as well as the number of patients completing chemoprophylaxis were identified. The rates of disease during the same period were also documented. RESULTS: During the study, 202 patients with TB were diagnosed among aboriginal persons and 201 controls were chosen. Apart from age at diagnosis (35.1±20 years versus 45.7±19.7), differences in the prevalence of lymphadenopathy (5.9% versus 16.4%, P=0.0008) and pleural disease (21.3% versus 16.4%, P=0.00008), there were no differences in presentation between aboriginal and nonaboriginal people. Aboriginal people were more likely to have a history of contact with a patient with TB (53% versus 17.9%, P<0.05), to have received directly observed therapy (55% versus 33.8%, P=0.00002) and to have contacts who were purified protein derivative (PPD) positive (4±9 versus 2±3, P=0.002). These contacts were more likely to start isoniazid (2±3 versus 1±1, P=0.002). Overall, there was a significant decline in rates of TB among aboriginal persons compared with the general population, but there was a small increase in rates among all subjects in the final year of the study. CONCLUSIONS: In the present study, significant variations in rates of TB among different population groups in British Columbia were found. During the study period, there was a greater decline in the rates of TB among aboriginal persons. A greater use of directly observed therapy and greater use of chemoprophylaxis occurred among aboriginal persons, which may have contributed to this decline, or alternatively, it simply reflects the natural evolution of the TB epidemic.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.