Dinitrochlorobenzene Test for Anergy

To the Editor: The August 21, 1975, article by Roth et al. concerning response to dinitrochlorobenzene and croton oil failed to mention an important observation on the skin-irritant response of D.C.NB itself. The D.C.NB sensitizing dose of 2000 μg¹produces a chemical irritation with an early inflammatory response in most people who subsequently show a delayed response. Our observations²suggest that nonresponders more frequently do not show the early irritant response. Inadequate skin contact with the D.N.CB and lack of the early irritant response (which itself may enhance the chance of sensitization) could be falsely interpreted as D.N.CB anergy. . .