Influence of nutrition on postvaccinial tuberculin sensitivity.

Response to BCG vaccination was studied in 261 apparently normal preschool children in a community. They were classified into different nutritional groups based on deficit in weight for age. In addition, nine children who had kwashiorkor and were admitted to the hospital were investigated. They were given 0.1 ml of BCG vaccine, and 6 months later, tuberculin sensitivity was assessed using 5 U of PPD. Blood samples were collected from 84 subjects and leukocyte migration inhibition was determined using the same antigen. After BCG vaccination, over 80% of children in the community showed positive tuberculin test, irrespective of the extent of growth retardation. There were no significant differences in the size of induration or the percentage of reactors between the various groups, indicating that the immune response to BCG vaccination is not affected by milder grades of malnutrition. However, the skin test was negative in most of the children who had had kwashiorkor. Leukocyte migration inhibition was similar in all the groups of children including those with kwashiorkor indicating that sensitisation of lymphocytes was not influenced by the nutritional status. In children with kwashiorkor, the leukocyte migration inhibition test was positive though the skin test was negative, suggesting that the former may be a better measure of assessing the response to BCG vaccination.