Contact allergic reactions in patients with atopic eczema.

The controversy concerning the sensitizing potential of a common agent to which there is contact sensitivity, dinitrochlorobenzene, has been reassessed by Rees et al. (1). Dose-response relationships for contact sensitization and elicitation at three different concentrations of dinitrochlorobenzene were determined for 22 patients with minimal atopic eczema compared to 27 non-atopic healthy control subjects. Atopic patients were significantly less responsive, with smaller reactions at all challenge doses and exhibited flatter challenge doseresponse curves than did healthy controls. This is in keeping with the classic cytokine route of sensitization, which indicates that atopics should be less prone to sensitization under experimental conditions.