Is The Appearance Of Red Scratch Marks On Skin Symptom Of Dermatitis?

My friend has been treated for accute dermatitis. She was to the dr two weeks ago and the dr. says she is 75% healed. She reduced the strength of her meds and gave her another injection. In the past week there have been red streaks (like scratch marks) that appear on her skin -- last for a few hours or overnight and then disappear. Is this part of the dermatitis process or should she be concerned about infection. The don't itch or burn and she has no fever of chills or other signs of infection,