Another thread reminded me of a question I had from when I lived in Japan. While there, I met a relatively good number of people who had some sort of skin disease that (from what could be seen) usually covered the full neck but not usually the face, and looked to go down further on their body. The skin looked scaly and slightly pinkened and not quite as “tight” (e.g. wrinkled, puffed out) as normal skin, and flaking off.
I assume that there’s various things that could cause this, but it seemed sufficiently prevalent that I would have to guess that there is one disease/disorder that most could be attributed to.
I see a dermatologist for fungi infection, and there are many children and adults with these condition.
In Japanese, it’s commonly called アトピー,(atopy) and the number of people with it have increased in the last 10 to 15 years. This is discussed in the media from time to time, and the “sick house” syndrome is a usual suspect. Home building codes have been changed recently to increase ventilation and reduce certain chemicals among other improvements.
Looks like it might be psoriasis, going from the pictures and that it commonly effects the scalp (something I’d forgotten. It tended to go up the neck and then under the hair, showing all around the hair line.)
Well, “Atopic dermatitis” isn’t much of a diagnosis. All it means is “skin inflammation caused by some (probably unknown) allergy.” Other than being associated with asthma and other allergies, no one really knowns exactly what causes it. Psoriasis is also associated with allergies, but it looks somewhat different.
There are other mysterious rashes not associated with allergies. Two I can think of are Pityriasis rosea and Pompholyx (hand-foot eczema).
All rashy skin problems are prone to secondary infections, particularly staph. This makes them even more disgusting, in case you were wondering about that.