hi there, what you have described sound like a furuncle
or it could be a sebaceous cyst
. Get your husbands blood sugars done. A furuncle is infectioon of a hair follicle and usually it is aggravated by diabetes
. He will need a course of antibiotics to take care of it. If it is a sebaceous cyst then you will need to to visit a doctor and see if it can be excised so that it does nto recur. Either case do visit a doctor and let him take a look at it and decided a course of treatment. Take care.