Diabetic dermopathy

Diabetic dermopathy is a term used to describe the small, round, brown atrophic skin lesions that occur on the shins of patients with diabetes. Diabetic dermopathy is the commonest skin condition that occurs in patients with diabetes mellitus and is associated with other microvascular complications of diabetes such as retinopathy, nephropathy and neuropathy and also with large vessel disease.

This chapter is set out as follows:

• The underlying mechanism for diabetic dermopathy is unknown

• Diabetic dermopathy is more common in older patients and those with longstanding diabetes
• In older patients diabetic dermopathy was found to occur after a shorter duration of diabetes, whereas in younger patients lesions occurred only after ten years in patients less than 20 years of age
• Lesions are asymptomatic 

Distribution

• ​Usually the shins in a bilateral symmetrical distribution
• Rarely the arms, thighs, trunk and abdomen

Morphology

• Lesions begin spontaneously as non-blanching, scaly, red or purple, round or oval macules or papules. There may be induration, with a central depression or vesiculation
• Established lesions are generally round, brown, and atrophic less than 1cm diameter, some may be elongated and up to 2.5cm in diameter
• Some lesions may have fine scale 

• Histological changes include epidermal atrophy with flattening of the rete ridges, dermal fibroblastic proliferation, altered collagen, dermal oedema and an increase in dermal capillaries, with a perivascular inflammatory infiltrate, changes to the vessel walls and melanin and haemosiderin deposition (reference: Rook's Textbook of Dermatology)

• Lesions lasts on average 18-24 months, before fading to minimally atrophic macules, or clearing completely

• No treatment is recommended or has been shown to be effective. Cosmetic camouflage may be used to disguise the appearance of the skin lesions if required