What Causes Severe Itching On Forehead And Cheeks Of A Diabetic?

my mother is 67 year old and has diabetes since past 10 years. the sugar levels are slightly on the higher side within + 20 range for both fasting and after meal levels. Off late she has developed some burns n her forehead , although there was no injury. there is lot of itchiness on the forehead, in the eyebrows, following towards the cheeks and going upto the neck. She is using steroid ointment. the itchiness increases in the night. kindly suggest a suitable diagnosis and treatment. thanks