The distribution of tuberculin reaction among children at school entry in Madaba, Jordan

The present study reports the results of a tuberculin test survey of a representative sample of BCG unvaccinated children at school entry age in the Madaba district in Jordan in 1991-92. Preschool household contacts of positive schoolchildren and a 5% random sample of negative schoolchildren were also screened by the same test. Three out of the 746 children screened by the initial school survey were found to be positive giving a prevalence rate of 0.4%. The overall prevalence rate of infection among preschool contacts was found to be 10.1% [28.6% among the contacts of the positive schoolchildren compared to 8.1% among contacts of the negative children]

On the specificity of the tuberculin reaction

The classic studies of R. Koch'a showed for the first time that an organism infected with tbc reacts in a completely different way to the introduction of tbc cultures and various cultures derived from them. drugs than a normal animal that has not yet had a chance to get acquainted with the tbc antigen. Koch's main experiments boil down to the following: if you inject a healthy guinea pig with a pure culture of tbc rods, then, as a rule, the wound at the site of the injection heals up and seems to heal in the first days: however, then, within 10-14 days, a solid a nodule that soon opens and forms a place ulcerating until the death of the animal; at the same time, swelling of the nearest lymph glands develops, and later the generalization of the process occurs.

Occurrence of Mycobacterium bovis infection in cattle in Kaduna metropolis and its environs

The tedious nature of tuberculin tests in Nigeria, warrants the need for an alternative rapid animal-side means of diagnosis. The aim of this study was to provide information on the epidemiology of Mycobacterium bovis infection in cattle. An experiment was conducted to evaluate the occurrence of M. bovis infection in cattle in Kaduna metropolis and it's environ. A total 239 heads of cattle from 8 herds were randomly selected and tuberculin tested, two herds being from each of the four local government areas involved and pooled milk samples from the eight herds were tested for acid fastness. Also, all heads of cattle totaling 2978 slaughtered at the 2 abattoirs during the month of May, 2012 were examined at postmortem and tissues with lesions compatible with lesions of were collected and tested for acid fastness. The results of the experiment showed that only 23 (9.6%) of the animals tested were classified as reactors and these came from only one of the eight herds studied. A clear swelling was seen in each of the positive cases. Out of the eight herds tested, 6 (75%) were settled and the remaining 2 (25%) were semi- settled. Similarly, 6 (75%) of the herds were for mixed production system and 2(25%) were kept solely as dairy herds. Positive tuberculin test was only observed from among one of the six settled herds 1(17%) while cattle in the remaining 5(83%} settled herds all tested negative. All the two semi-settled herds (100%) tested negative. The tuberculin reaction among different production systems showed that only 1 (50%) of the dairy herds tested positive and all the 6 (100%) mixed herds tested negative. Atuberculin positive reaction of 19 (7.9%) was observed among the females and 4 (1.67%) among the males. The chi-square test of significance between the tuberculin reaction and sex of the animals showed no significant effect (P > 0.05). Hence, it can be concluded that, Mycobacterium bovis was neither cultured nor isolated and therefore, could not be confirmed responsible for the observed reactions. However, its involvement is strongly suggested by both its higher values compared to those for Mycobacterium avium in the single intradermal comparative tuberculin test and the observed in the stained smears of both the milk samples collected and the bovine tissues from the abattoirs.

Efficacy of BCG Vaccine and Role of Non Specific Sensitivity Due to Atypical Mycobacteria

This paper attempts to summarizes possible reasons for BCG trial failure in India. It also lists out some of the important controversies and questions raised with regards to BCG trial in the context of Non Specific sensitivity. It emphasizes on the fact, that Tuberculin test does not accurately reflect individual’s responded immunologically to mycobacterium, it only indicates nature of immune response that has been elicited in an infected individual. The dynamics of tuberculin reaction needs to be understood through immunological considerations. Categorization of Tuberculin test results factoring in immunological considerations,will have great implication on the interpretation of tuberculin test and therefore on the estimation of annual risk of infection of tuberculosis.

Pattern of cutaneous tuberculosis among children and adolescent

Cutaneous tuberculosis is one of the most subtle and difficult diagnoses for dermatologists practicing in developing countries. It has widely varied manifestations and it is important to know the spectrum of manifestations in children and adolescent. Sixty cases (age<19 years) of cutaneous tuberculosis were included in this one period study. The diagnosis was based on clinical examination, tuberculin reaction, histopathology, and response to antitubercular therapy. Histopahology revealed 38.3% had skin tuberculosis and 61.7% had diseases other than tuberculosis. Among 23 histopathologically proved cutaneous tuberculosis, 47.8% had scrofuloderma, 34.8% had lupus vulgaris and 17.4% had tuberculosis verrucosa cutis (TVC). Most common site for scrofuloderma lesions was neck and that for lupus vulgaris and TVC was lower limb. Cutaneous tuberculosis in children continues to be an important cause of morbidity, there is a high likelihood of internal involvement, especially in patients with scrofuloderma. A search is required for more sensitive, economic diagnostic tools. DOI: http://dx.doi.org/10.3329/bmrcb.v38i3.14335 Bangladesh Med Res Counc Bull 2012; 38(3): 94-97 (December)