Blisters, inflammation, whole-body itchiness – doctors can't diagnose yet. Help please?

##### Current issue #####

Latest occurrence started in late December with a few spots on right elbow shortly followed by the left elbow. Every small spot was steadily growing larger, eventually merging into large patches on each elbow. Started applying custom-made prescribed creme (1) and taking ashwagandha (2) around Jan 15th. Alongside with elbows, small spots started to develop on the knees around Feb 4th. The whole body started to feel itchy.

Saw a dermatologist on Feb 5th, doctor said to stop applying the creme: it was making the skin smooth, and he needed the rash to develop more so that he could scrape a bit of the tissue for analysis.

I stopped applying the creme, but also started taking food supplements (3) and (4). Over the week of Feb 5th-12th the disease was developing extremely rapidly, culminating in about a dozen of small blisters, mainly on elbows. Skin was very inflamed and irritated, felt as if I had a mild burn.

On Feb 13th went to a dermatologist again. Doctor ruled out psoriasis because of the blisters and took a sample of the liquid from one of the blisters.

On Feb 14th, based on the sample taken, the doctor diagnosed me with allergic dermatitis with eczematization. Doctor prescribed a one-off hormonal shot (5), 20-days course of antihistamine tablets (6), and applications of skin creme (7). Pretty much immediately after the inflammation got significantly reduced – the skin still looked ill, but didn't feel as "burning" anymore. The blisters suddenly went away too.

However, after that sudden relief around 10 days ago, the disease continued to slowly spread further, outward from the main patches on elbow. The whole body continues to itch. There is a new bumpy rash appearing on the bottom, under the armpit, on the face. There are also some blisters on the face, although they are much smaller and milder.

I suspect that the whole body itchiness developed when I started taking the supplements (2) and (3), so I stopped taking them since Feb 20th.

Finally, visited a doctor today (Feb 26). Because of the growth of the patch, the doctor was a bit shocked. Both him and his colleague looked perplexed, they can't diagnose it yet. Doctor suggested to do a biopsy to help with the diagnosis. Some hypotheses they were discussing:

- Lupus;
- Multiform exudative erythema;
- Erythema elevantum et dintinum.

##### Previous medical history #####

Around 2007, I had some similar rash on the elbows. Doctors said it's psoriasis, so they prescribed a custom-made cream (1) and supplements (3) and (4).

Even since, the rash was coming back several times – around 2009, 2011. Doctors were confirming psoriasis. Later, whenever the rash would come back, I would just apply the creme myself without consulting doctors, and it was going away.

##### Medications and food supplements #####

(1) - Custom-made cream prescribed in 2007 and last made in 2011. Recipe lost, but it's based on betamethasone and is very strong (doctor's words).
(2) - Ashwagandha.
(3) - Docosahexaenoic acid, Essentiale (Phospholipid, Tocopherol, Thiamine, Cyanocobalamin, Riboflavin), vitamin D, vitamin A.
(4) - Fish oil.
(5) - Flosteron (based on betamethasone).
(6) - Levocetirizine.
(7) - Miramistin, triamcinolone.

##### Recent potentially-related events #####

- Started to actively go to gym and do strength training around 9 months ago. Diet has changed, now it's heavily leaning towards natural proteins, including eggs, chicken, cottage cheese. It's not impossible that eggs would cause an allergy.

- Around January 20th went skiing, lived in a bed-and-breakfast with friends. Took public baths with friends. Retrospectively, I'm not sure about the hygiene standards of the place I lived in.