Am. J. Respir. Crit. Care Med., Vol 149, No. 3, 03 1994, 620-624.
Evaluation of tuberculin reactivity in BCG-immunized siblings
RL Sepulveda, IM Heiba, A King, B Gonzalez, RC Elston and RU Sorensen
Department of Medicine, University of Chile Medical School, Santiago.
The purpose of the present study was to determine in BCG-immunized sibships
< or = 14 yr of age whether the correlations of intensity of tuberculin
reactivity support a genetic regulation of the response to BCG
immunization. The study population consisted of 659 healthy children living
in 265 households exposed to an adult with tuberculosis: 38 children did
not have a BCG scar, 327 children had one BCG scar, and 294 had two BCG
scars from vaccinations at birth and at 6 yr of age. There were 603 full
siblings, 16 half-siblings, and 40 unrelated children. Tuberculin testing
was performed by one trained nurse. Sibling correlations of the intensity
of the tuberculin response were calculated after adjusting for various
nongenetic covariates that could be important in predicting it. The sibling
correlations were significant at the 1% significance level. There was no
significant correlation of tuberculin reactivity among unrelated children
in the same household. These results are consistent with genetic regulation
of the development and persistence of tuberculin reactivity after BCG
immunization.
