Figure 1. Erythematous induration of the skin limited to the back.
Q: Which is the correct diagnosis?
- Scleroderma (systemic sclerosis)
- Scleredema diabeticorum
- Amyloidosis
- Cutaneous sarcoidosis
- Porphyria cutanea tarda
A: The correct answer is scleredema diabeticorum, a common, underdiagnosed skin manifestation of uncontrolled diabetes mellitus seen in 2.5% to 14% of diabetic patients.1,2 It most often presents with the insidious onset of painless induration and nonpitting thickening of the skin, predominantly on the upper back and neck. Biopsy of the skin usually reveals thickening of the dermis with deposition of collagen and hyaluronic acid without an inflammatory infiltrate.3
Of note, patients may present with similar skin changes acutely in conditions such as postinfectious scleredema (scleredema of Buschke) and paraproteinemias.
Treatment of scleredema is usually difficult, but options include radiotherapy, ultraviolet light therapy, low-dose methotrexate, psoralen, and extracorporeal photopheresis.4–7