What Causes Itchy Spots On The Hands And Fingers?

Hi, may I answer your health queries right now ? Please type your query here... Hi, I've had itchy spots on my hands and fingers over the last few weeks. I constantly scratch them and a blister develops, then it turns into an ulcerated, weepy looking sore. It usually dries up and heals in about a week, but there is one on the middle of my finger now which is really sore. I have Type 2 diabetes. Would this be a type of dermatitis or something more sinister to do with my diabetes? The weather has been very humid here lately and I am retaining fluid in my feet.