Scleredema is a connective tissue disorder that presents as diffuse induration of skin, most often involving the upper body. Scleredema can be associated with prior infection, monoclonal gammopathy, and diabetes mellitus. Pyoderma gangrenosum is a neutrophilic dermatosis that presents as an ulcer with violaceous borders. Pyoderma gangrenosum can be idiopathic or associated with various conditions. A 66-year-old man with a 20-year history of scleredema diabeticorum presented with idiopathic pyoderma gangrenosum in the affected area of scleredema on his neck. His pyoderma gangrenosum resolved after treatment with topical and intralesional corticosteroids. Diseases associated with scleredema, pyoderma gangrenosum or both are reviewed.

BACKGROUND: Scleredema is a rare sclerodermoid skin condition characterized by diffuse symmetrical thickening of the upper part of the body. Its association with monoclonal gammopathy and myeloma was recently described; very few cases have been reported to date.
METHODS: A 66-year-old Sri Lankan woman who had been followed in a dermatology unit for 34 years with diffuse systemic sclerosis presented with an acute exacerbation of the skin disease. Absence of Raynaud\'s phenomenon; sclerodactyly; characteristic lung, gastrointestinal, and cardiac involvement of systemic sclerosis; and repeatedly negative antinuclear antibodies test results led to reevaluation for the possibility of scleredema. Skin biopsies from four body sites showed normal epidermis and thickened reticular dermis with swollen collagen bundles separated from one another by clear spaces, resulting in fenestration. The skin appendages were not atrophied or bound down. Alcian blue staining showed interstitial mucin deposition. Serum protein electrophoresis demonstrated an abnormal monoclonal band in the β-region with a paraprotein level of 8.9 g/dl. Immunofixation showed an abnormal band in the γ-region consisting of immunoglobulin A and κ. Bone marrow biopsy revealed abnormal monoclonal plasma cells (15%) with multinuclearity. There was no evidence of end organ damage, and whole-body magnetic resonance imaging did not reveal any evidence of bone involvement. The patient\'s diagnosis was revised as scleredema type 2 associated with IgA-κ, and she was referred to a hemato-oncologist for chemotherapy, which led to significant improvement in the skin condition.
CONCLUSIONS: Scleredema is a rare disorder that has an enigmatic, rare association with monoclonal gammopathy. Dermatologists should be aware of this rare but important association.

Scleredema is a deposition disorder which presents as diffuse, symmetric, non-pitting skin induration from dermal deposits of glycosaminoglycans (\"mucins\"). It classically affects the upper back and posterior neck, often causing skin tightness and decreased range of motion. In most patients the clinical course is chronic and treatment options are limited. We report a case of a patient diagnosed with scleredema associated with longstanding insulin dependent diabetes who was treated successfully with IVIg. Additionally, we have reviewed the literature reporting other patients with scleredema treated with IVIg.