Skin sensitization to 2, 4 dinitrochlorobenzene (DNCB) in the first months of life.

The skin reactivity to 2, 4 dinitrochlorobenzene (DNCB) was evaluated in 94 healthy term neonates, aged 1-30 days and in 190 infants aged 2-9 months. For contact sensitization to DNCB an initial dose of 1 mg DNCB and a challenge one of 0.1 mg were used. Sensitization was induced in 6.7% of neonates in the first 15 days of life. This proportion rose to 25.7% by the end of the first month, to 63% in the third month and to 91% in the ninth month. It is concluded that DNCB test is a safe and simple screening test for evaluating cell-mediated immunity in the first months of life. It appears to have some advantages over the skin tests using specific antigens, as a positive result with DNCB can be obtained at an earlier age.