My hair fell out for 2 years after getting cortisone shots and taking cortisone orally. I would not recommend this. I went through a divorce and got a new job. No more stress and my hair came back.
My daughter also starting losing her hair when she was 12. The only thing I would let her do was use the cortisone cream. I was afraid that the shots would chase it around like it did for me. Her hair eventually grew back after a year of creative hairstyling, but the hair loss was as big as an apple. When you go the derm, he will suggest cortisone shots. I would not recommend this. Try the cream first. Does he stress out alot? try and not stress him out. I know that's hard with a 6 year old, but stress really seems to make it worse. I hope this helps and your son's hair loss is only for a short time.
When my daughter was 4yrs old she had a very bad case .. on top of her head in an exclamation point formation of bald spots in two areas .. also around base of head but not the nape of the neck. She saw a pedi dermatologist who did topical potent cortisone cream which worked in ev. case. It would take about 30days and then finally some regrowth that looked like peach fuzz would come in and then eventually was back normal.
We were told back then (13yrs ago) that if it doesn't affect the actual nape of the neck there is a 90% regrowth rate. And that shots only speed up the process vs. the creams .. if it's coming back it will do so a) on its own and take longer b) come back with the cream or c) come back faster with the shots.
The creams must be put on with Qtip or gloves cause you don't want to absorb it into your skin.
Today she is 17yrs old and at times of bad allergies outside she will get a minor flare ... but nothing like it was at age 13.
All bloodwork was and still is normal.
I can understand that this must be very stressful for both you and your son, not knowing is a very difficult thing. I was diagnosed with Alopecia Areata (spots) at the age of 7 and as this was almost twenty years ago now they did not know what to do. As the previous posters have said there are medication options that you can use to try to grow the hair back. If your son has alopecia and he does not respond to the cortisone please know that there are very few side effects to having alopecia and that it should not interfere too much with his life.
Here is a great website www.naaf.org, its the National Alopecia Areata Foundation.
Best of luck and keep us updated on what the doctor says on the 20th!!!