Allergic contact dermatitis

A An 11-year-old Hispanic boy with allergic contact dermatitis (ACD) on the abdomen.The geometric nature of the eruption and proximity to the belt buckle were highly suggestive of ACD to nickel; patch testing was not needed.B A Black woman with ACD on the neck.A punch biopsy demonstrated spongiotic dermatitis that was typical of ACD.The diagnosis was supported by the patient's history of dermatitis that developed after new products were applied to the hair.The patient declined patch testing.C A Hispanic man with ACD on hair-bearing areas of the face where hair dye was used.The patient's history of dermatitis following the application of hair dye was highly suggestive of ACD; patch testing confirmed the allergen was paraphenylenediamine (PPD).