Therapy with corticosteroids is used for the treatment of most and additional therapy is available and dependent upon the type of HS. Newer medicines such as
imatinib and mepolizumab are said to be promising. So, should your son have HS, there is reason to be optimistic regarding a positive response to currently available therapy.
You should request, of his doctor, an additional explanation for the tentative diagnosis of pre-hypertension.
Good luck.