Many of us with eczema have multiple forms. This is common with autoimmune diseases. I have 3, Allergic Contact Dermatitis, ACD and Grover's Disease, GD and have also have had Perioral Eczema. My first form was ACD and began as hand eczema. Have you had the 5 Day Extended Patch Test to diagnosis any allergens? My grooming products and dish soap and other cleaning products triggered my hand eczema as well as adhesives. I had Scotch Guarded some chair pads which triggered my first outbreak, very bad chemicals in Scotch Guard. I can't even sit on it when dry.
Also GD biopsy must be taken at a specific stage to register. My biopsy for GD was at the end of my initial 1 year break out and was negative. I am a classic GD case and have no doubt I have this form. For me the cilantro works. In 4 years it's the only thing that worked. My derm offered to do another biopsy if I want it, but I I have no doubt I have GD.

@aprilfool As you may have read, I also have a rash that does not present like Grover's (those red itchy Grover's bumps have gone with the Cilantro) However, My initial rash started on my head and I did have what looked like a hive(ish) rash that accompanied the Grover's as it progressed. All of the rashes left me for about a month or two (with the exception of the itchy bumps on my head) after starting the cilantro. However, the hive like rash re- appeared. It started really small and gradually built up to where it bothers me quite a bit now. It travels. Some days on lower legs, others on upper thigh and buttocks, others on back and arms AND I would also get itching on my palms. I could see tiny little bumps on my palms (no color) that itched like crazy. My chest and neck also get red and it feels like it's on fire, and I get almost a blister like outbreak. It's weird! I have been trying to figure this rash out for a little while now. Derms have no idea, and say it does not present like Grover's, but since I was diagnosed with Grover's through a biopsy, some think it still may be just that. Others think it's another form of eczema others thought it was hives. So I have no REAL diagnosis for this issue. Just Doctors throwing Prednisone at me and shooing me away. I thought it was an allergic reaction to the yogurt I added to my smoothies because it got better (almost gone as soon as I stopped using the yogurt.) But the last two days it has come back strong! I have not done the 5 day extended patch test because my derms don't offer it and from what I am told it costs over $1000, so I have put it off. I have NEVER been allergic to anything prior to this and I never had issues with rashes before last September when this all started. (I will be 56 in October.) I am going to set up an appointment with the Mayo Clinic next. I have to drive about 5 hours to get there, so it may be a while before I can get in. Until then I am going to keep trying to figure this thing out.