Rash on 4 year old

Hello, I was hoping someone could have any helpful thoughts on what this rash may be. It is raised, very itchy and painful, relatively red, some have a white center, and some seem to have almost a white/lighter outline around each one.

Background: He is 4 years old, has had eczema for most of his life, mainly on the back of his legs. Oatmeal baths and 2.5% hydrocortisone has cleared it up when it flares up, along with moisturizing fairly regularly after baths.

On the 25th, he threw up and had a temperature. On the 25th night I thought I noticed his eczema was flaring up behind his legs so I put cream (2.5%) on it.

On the 26th his temp was gone and by the evening his rash was on his legs as well as his elbows. It was very itchy for him and painful. I put cream on it again (2.5%) and that night he was up every 20 min. crying about how it hurt and itched. Ice packs were the only thing that settled him.

We went to the doctor on the 27th, he said it was probably a strange presentation of his eczema or something in our detergent that he was allergic to. The rash was now also on his groin and bottom. He wanted me to put 2.5% hydrocortisone on it twice a day and give him Benadryl at night. He wanted to see the rash again the next day. That night my son still woke up many times, but not quite as many.

Today we went back to the Dr. and he said he thought it was looking better, though it had spread to his hands, a few on his ears, a few on his penis, one on his face and one on the bottom of his foot. The doctor sort of just said it was fine and that he wasn't worried. They did test for strep, which came back negative.

I suppose it could be just an allergic reaction to something, but our life is pretty boring right now. I truly can't think of anything different we've done or eaten or worn that could have made him break out in a rash like that - it's also never happened before. It really doesn't seem like it could be eczema either, but I don't know.

I was hoping someone could give a little input if they have time.

The rash could be 2 possibilities: staph or yeast. either can be cured by antibiotics or nystatin.

I had to go to several different doctors to finally get my daughter treated. They kept saying it was eczema I said no its not. She suffered for 6 months before I found a doctor that helped.

Ask for a test - they can test for bacteria or yeast. Test for both. They swab the rash and then grow a culture.

I get both types of rashes and the doctors want to tell me its eczema.

Also, change your laundry detergent to something for sensitive skin. Like All, or Dreft. No perfumes. Wash his clothes on hot water, and use hydrogen peroxide. Then do another rinse cycle to wash out all the detergent/peroxide. The hot water and peroxide kills dust mites. the second cycle washes out the peroxide which can be irritating to the skin. Plus the peroxide doesn't bleach out the colors.

Next is keep a diary of his food consumption. Put him on a bland diet first, give him the same thing to eat for a couple of days to see if his rash improves. Then add more different foods. Eczema usually is caused by allergies...either internal (foods) or external. The rash can show up instantly or about a half hour.

Milk, eggs, wheat, corn etc..are high on the list that most people are allergic to.