most probably your rash on the skin folds is a fungal infection called taenia corporis It can come for even a non diabetic ,but common in a diabetic because of excessive moisture in the skinfolds,The sugar in the sweat is a good food for the fungi( bacteria too).it is a plant growing on you like the mushroom on the tree or a mould on a old bread! your control of sugar must be near optimal,you need a anti fungal cream like candid or quadriderm and bath twice a day,change of clothing too,preferably cotton.thereafter daily candiderm powder is needed foe six weeks or longer If you are not regular in therapy ,disease will be your permanent friend if you assure this insurance against complications of severe wound infection,bleeding loss of sleep,embarrassment in the public due to ugly scratching can be provided.monitory insurance is not easy to get for this alone