Upper back of an African American female patient with scleredema. Scleredema is a thickening of the skin caused by deposits of mucin in the skin's dermis. This case is secondary to diabetes and is known as scleredema diabeticorum. It occurs symmetrically across the neck and upper back and can restrict movement. The cause is not known. Treatment may include topical steroids, light therapy, immunosuppressants and physiotherapy.