This article describes the clinical presentation, differential diagnosis, and treatment of 2 unrelated cases with different presentations of black-spot
Toxicodendron dermatitis. In the first case, a healthy 7-y-old male presented with a
rash consisting of black dots with localized surrounding
erythema on the left arm. The
rash then progressed to a vesicular, pinpoint, raised
rash spreading to the face, arms, and neck. In the second case, a 4-y-old male presented with non-pruritic, black, flat, non-erythematous lesions that did not progress. This patient's older sibling had been diagnosed with poison ivy 1 wk prior, and they attended the same child care where the poison ivy was thought to be acquired. In both cases, diagnosis of black-spot
Toxicodendron dermatitis was made. The black spot of
Toxicodendron dermatitis is caused by
urushiol oxidation on exposure to air. The subject may or may not go on to develop
allergic contact dermatitis after the exposure. Diagnosis of this
dermatitis is made on clinical presentation, with careful consideration of history, distribution, and lesion morphology. When allergic
dermatitis does develop as in the first case, systemic treatment with oral
steroids is recommended. In both of these cases the black dots completely resolved in 2 to 3 wk. Dermatologic referral for dermoscopy and biopsy may be necessary if the
dermatosis does not resolve as anticipated.