SKIN HYPERSENSITIVITY AND IN VITRO LYMPHOCYTIC REACTIVITY TO TUBERCULIN IN CHILDHOOD

The mitogenic effect of old tuberculin was studied in cultures of peripheral lymphocytes from 113 children with a negative delayed dermal hypersensitivity reaction to tuberculin and from 30 children with a positive dermal reaction. A significant number of cells in mitosis was seen in (a) 23 of 100 randomly chosen children and 11 of 13 BCG vaccinated children in the absence of delayed dermal hypersensitivity to tuberculin, (b) 18 of 20 children with a positive dermal reaction but no history of active tuberculosis, of healing tuberculosis, or of a history BCG vaccination, and (c) 4 of 10 children with active tuberculosis. It is suggested that the in vitro lymphocytic response to tuberculin may be useful in detecting sensitization not expressed by delayed skin hypersensitivity. © 1968 The C. V. Mosby Company.