What does your dermatologist say? Have they done any tests?
Any allergies? You've had this for such a long time I can't imagine it's a contact allergen like soap or a cleanser but food allergies can present in unusual ways.
I was just looking up info on atopic dermatitis, a type of eczema. It's very itchy, often begins in childhood and is chronic, although the severity may wax and wane over the years. Typically it affects the face and the inside of the elbows and knees but it could show up in only one spot like the face. Kids are more likely to get AD if they have (or have a family history of) asthma or hay fever.
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