A study of the lepromin and tuberculin reactions. The correlation between the two reactions and the influence of BCG vaccination on nonreactors in healthy leprosy contact children in Djakarta

ABSTRACT

1- Lepromin and tuberculin tests have been made on 901 healthy leprosy-contact children between the ages of 1 and 15 years. They showed in total a much lower Mantoux than Mitsuda rate, 30 vs 61 per cent. With growing age the number of reactors to both tests increased markedly, but in the third age group (11-15 years) the number of tuberculin reactors increased much more markedly than that of the Mitsuda reactors. This finding is attributed to the fact that the younger children had had almost exclusively contact with their leprous environment, whereas the older children had wider contact with the normal population in schools and playgrounds, where they had greater chances of meeting tuberculosis infection. 2- In the correlation between the tuberculin and lepromin reactions, there was agreement between the two reactions (simultaneouly positive or negative) of 59 per cent. The positive association was 25 per cent. Among the nonagreeing reactions the tuberculin-negative, Mitsuda-positive group was the largest, about 36 per cent. Assuming that the tuberculin positivity was induced by previous contact with leprosy, there was found a positive association of the two tests in 41 per cent (in 25, 47 and 52 per cent in the respective age groups), and a positive tuberculin reaction associated with lepromin negativity in 14 per cent (6, 15 and 72 per cent respectively). These figures show little evidence of tuberculin positivity having been induced by contact with the Hansen bacillusAssuming induction of MItsuda positivity by previous contact with tuberculosis, there was found a positive association of the two reactions in 83 per cent (40, 58 and 90 per cent in the respective age groups). A certain degree of influence on the MItsuda reaction by tuberculosis cannot be denied, since of 277 tuberculin reactors 83 per cent are also lepromin positive. At the same time, however, it was found that positive Mitsuda reactions occurred in 52 per cent independently of the tuberculin reaction, probably through contact with leprosy itself...