She reported having no pain with the hyperpigmented areas but does have foot pain secondary to neuropathy. The patient is diagnosed with diabetic dermopathy, and she begins working with her physician on achieving better control of her diabetes.
Diabetic dermopathy is a constellation of well-demarcated, hyperpigmented, atrophic depressions, macules, or papules located on the anterior surface of the lower legs that is usually found in patients with diabetes mellitus.(DM). It is the most common cutaneous marker of DM.
Diabetic dermopathy is found in 12.5% to 40% of patients with diabetes and most often in the elderly.
Etiology and Pathophysiology: The exact cause of diabetic dermopathy is unknown. Some of the suggested reasons include:
• Diabetic dermopathy may be related to mechanical or thermal trauma, especially in patients with neuropathy.
• Lesions have been classified as vascular because histology sections demonstrate red blood cell extravasation and capillary basement membrane thickening.
• There is an association between diabetic dermopathy and the presence of retinopathy, nephropathy, and neuropathy
- Lesions often begin as pink patches (0.5 to 1 cm), which become hyperpigmented with surface atrophy and fine scale.
- Typically distributed on the pretibial and lateral areas of the calf.
Diagnosis : is clinical but if biopsy of the lesion is done the histology shows epidermal atrophy, thickened small superficial dermal blood vessels, increased epidermal melanin and hemorrhage with hemosiderin deposits. These findings are not all present in biopsy specimens.
Differential Diagnosis: Consider the following when evaluating patients with similar skin conditions:
• Early lesions of necrobiosis lipoidica diabeticorum—Erythematous papules or plaques beginning in the pretibial area, but become larger and darker with irregular margins and raised erythematous borders. Telangiectasias, atrophy, and yellow discoloration may be seen. The lesion may be painful
• Schamberg disease (pigmented purpuric dermatosis) is a capillaritisthat produces brown hemosiderin deposits along with visible pinkto- red spots like cayenne pepper on the lower extremities. It is not more common in diabetes but may resemble diabetic dermopathy. A biopsy could be used to distinguish between them.
• Stasis dermatitis—The typical site is the medial aspect of the ankle. Early lesions are erythematous, scaly, and sometimes pruritic, becoming progressively hyperpigmented.
• Traumatic scars—There is no scale, lesions are permanent, and edema is not usually present.
Management: There is no effective treatment and it is not known whether the lesions improve with better control of diabetes.
Some studies have shown that patients may benefit from 15 to 25 mg chelated zinc daily for several weeks
Sometimes the lesions may resolve spontaneously so reassure patients that the lesions are asymptomatic and may resolve