What Causes Red, Scaly Splotches On Body?

I have many red, scaly splotches on my body. The first came about a year ago and started like a bite. It itched very badly and soon tripled in size. Then I got 2 on my stomach and 1 in clevage. Now I have probably 20 on my body. There are about 15 on my legs which appear to be symetrical on each leg. They appear to have placque and peel. I went to a dermatologist and he said he was hesitant to say it was psoriasis. Also have them on my scalp hairline. Now I am getting them on my lower back and they really itch. What is this?