I am happy to help you today.
Are you currently on any medications?
Do you have any health problems?
Awaiting your reply,
I know I am asking a lot of questions but there are a lot of possible causes.
Does anyone in your family have the same thing?
Has it been this way all your life or when did it start?
I am going to suggest that you get a skin culture to see if there is an infection causing this.
It is possible that it is something else but since your doppler studies were normal and you don't have diabetes we nee to check all the options.
With it blistering it sounds like an infection.
Have you ever heard of the flesh eating disease?
I am not saying that you have that of coarse.
There are strains of bacteria such as STrep A that can cause deteriation of the skin.
I also suggest if ok with your doctor to start on a multivitamin and vitamin c to help your skin.
Your skin and hair gets nutrients last so if you are deficient in vitamins or other nutrients your organs will get everything first and if anything is left over it goes to your skin and hair.
You are welcome.