Itchy Blisters What Might Be Causing Itchy Rashes That Result In Blood Blisters When Scratched?

What might be causing itchy rashes that result in blood blisters when scratched? - itchy blisters

My neighbor is 19th Last year, a recurring itchy spots on the neck and chest, which had not come in packages, but still below the surface of the skin. If they develop itchy blisters on the skin of blood under the skin for several days and are not cured. Suggestions as to where to look for answers? Any idea what might that be?