Hi,
How are you? Its been 7 months since your post. Hives are raised, red, itchy welts, seen here on the chest. The majority of urticaria develop as a result of allergic reactions. However, they may be associated with autoimmune diseases, infections (parasitosis), drugs, malignancy, or other causes. Are there other signs or symptoms present? Complete history, physical examination and laboratory tests are needed to rule out other causes. Take care and do update us.
Could it be a keloid? I get keloids but only in the center of my chest...they've grown together kinda. It is raised and mine don't go away. It's stuck there until I go try to get it removed. This is not as common in white people as those with darker skin. Perhaps you can google keloids. I think they fade away for some people (just not me) :(