A previously well 8-year-old girl presented with a florid inflammatory eruption affecting her face and arms. She had initially noticed a linear erythematous lesion on her left cheek. This progressed over 24 h into an itchy vesicular eruption with severe periorbital oedema. A clinical diagnosis of impetigo was made in the absence of any initial history of contact exposure. There was no improvement with antibiotics. The following day, direct questioning revealed that she had been playing in a garden known to contain poison ivy (Toxicodendron radicans, previously known as Rhus radicans). This exposure occurred in Texas, and she had returned to the UK 5 days prior to the onset of the rash. The rash improved with steroid and antihistamine treatment (figure 1).

Poison ivy is the most common cause of allergic contact dermatitis (ACD) in the USA. 1 The plant is not found in the UK. Linear erythematous streaks develop soon after the skin is exposed to urushiol, which is found in the resin of poison ivy. 1 2 Vesicles typically occur 12–48 h after exposure. 1 Urushiol does not evaporate well and contains allergens (pentadecylcatechols) that can persist on contaminated clothing for years. 2 Smoke from burning poison ivy can provoke ACD. 2 The treatment for poison ivy dermatitis varies depending on the severity of the reaction and includes antihistamines and steroids. 1 2 In the global village, children may present with poison ivy dermatitis in non-endemic settings due to the resilience of urushiol on contaminated objects originating from endemic areas.