The effects of androstenediol and dehydroepiandrosterone on the immune response to BCG at puberty.

In order to assess the effects of age-related changes of serum dehydroepiandrosterone sulphate (DHEAS) and androstenediol (AED) concentrations on BCG vaccination throughout the puberty period, we matched 41 prepubertal (mean age 8.63 +/- 1.36 years, range 8-14 years) and 43 pubertal (mean age 13.8 +/- 1.31 years, range 10-16 years) schoolchildren who were PPD negative and free of disease or medication known to affect immune function. The tuberculin test was performed 8 weeks after vaccination and tuberculin response and hormone levels were compared between prepubertal and pubertal subjects. We found a higher tuberculin response in the pubertal group when compared with the prepubertal ones. The pubertal children had 79.1 per cent tuberculin positivity compared with 46.4 per cent of prepubertal children (p < 0.05). Diameters of induration of the tuberculin test among prepubertal students vs. pubertal students were 9.5 +/- 3.8 mm and 11.9 +/- 3.7 mm, respectively (p < 0.005). Pubertal stage, testis volume, and pubic stage were also found to have significant effects on tuberculin test results. No difference was observed between both sexes with regard to responses of the tuberculin test in either the prepubertal or the pubertal group (p > 0.05). DHEAS and AED levels in the tuberculin-positive subjects were found to be significantly higher than tuberculin-negative ones (p = 0.040 and p = 0.046, respectively). Among both these hormones, only AED levels were correlated with tuberculin test responses. These results suggest that AED may play a role in the immunity to BCG vaccination and further immunological investigations are warranted to provide support for this idea.

Primary drug resistance and molecular epidemiology of Mycobacterium tuberculosis isolates from patients in a population with high tuberculosis incidence in Turkey.

To determine the rate of primary drug resistance and compare the fingerprint pattern diversity of the resistant and sensitive Mycobacterium tuberculosis isolates, antituberculosis susceptibility testing and restriction fragment length polymorphism (RFLP) analysis were performed on 88 M. tuberculosis isolates of the patients who were diagnosed as new tuberculosis cases in 2000. Primary resistance to isoniazid, rifampicin, ethambutol, and streptomycin were determined by the BACTEC method. IS6110 and pTBN12 were used as molecular markers. The frequency of resistance to at least one drug was 32.95%, whereas 10.23% of the isolates were resistant to more than one drug. Single-drug resistance to isoniazid, streptomycin, ethambutol, and rifampicin was found in 9 (10.22%), 7 (7.95%), 4 (4.54%), and 0 (0.0%) strains, respectively. Two M. tuberculosis strains (2.26%) showed multiple drug resistance. The combination of two fingerprinting procedures on a total of 88 isolates identified 58 (65.9%) strains as unique and clustered 30 strains in 11 clusters (clustering = 34.1%). The clustering rate for resistant and sensitive isolates was 13.8% and 40.1%, respectively. In conclusion; drug susceptibility testing showed that the majority of the drug-resistant infections involved either isoniazid or streptomycin alone. In addition to the high tuberculosis incidence, elevated primary drug resistance and high clustering rate indicate problems in the present control programs. New control strategies supported by molecular typing might be more effective to reduce tuberculosis.