Contact dermatitis from plants
Does anyone know of a plant that can cause linear bruising, i.e. under the skin rather than on the surface, with no itching, blistering, soreness, pain, etc? My 9 year old granddaughter noticed such bruising on her upper arm last week, which next day continued down to her lower arm. Spent a day at hospital having blood tests etc. (normal), then referred to a dermatologist who said it was probably a sting from a hornet or horsefly, which I doubted as they are usually very painful and there is swelling and puncture mark, which she doesn't have, and anyway next day a similar patch appeared on the other arm and she hadn't been outside in the meantime. Then we discovered a schoolmate had almost identical bruise-like marks on one upper arm, now going further down, so back to hospital. This time told it was contact dermatitis from contact with a plant, which again I find hard to credit as there is no inflammation or discomfort, just lines and patches of reddish purple bruising. Does this ring any bells with anyone?