Scleredema Diabeticorum in a Patient with the Normal Range of the Hemoglobin A1c Level and Impaired Glucose Tolerance

Scleredema diabeticorum is an uncommon skin disorder showing a diffuse, symmetrical, and non-pitting persistent induration developing initially on the nape. It usually occurs in patients with poorly controlled or insulin-resistant diabetes mellitus. We present a 57-year-old woman with scleredema diabeticorum with hemoglobin A1c 6.1% (normal, 4.7% 6.2%) and impaired glucose tolerance. Alcian blue staining at pH 7.0 illustrated deposits of acid mucopolysaccharides between the collagen bundles in the reticular dermis, but the staining at pH 1.5 did not show the deposits. This case indicates that scleredema diabeticorum may be an early indicator of undiagnosed diabetes mellitus in some cases, and that impaired glucose tolerance test should be performed for individuals with scleredema even though the hemoglobin A1c level is within the normal range.