- Most commonly associated with diabetes mellitus, less often with monoclonal gammopathy or following an acute respiratory infection
- Presents as thickening and induration of the upper trunk, with nonpitting indurating edema in advanced cases.
- Markedly thickened dermis with increased collagen that may replace subcutaneous fat
- Thick, hyalinized collagen bundles separated by clefts
- Increased dermal mucin interspsersed between collagen bundles may be seen on special stains.
- No increase in dermal fibroblasts