Gottron's sign

Gottron's sign is a pathognomonic cutaneous manifestation associated with dermatomyositis (DM), which is an inflammatory disorder affecting the skin and muscles.

[1] The primary lesion of dermatomyositis appears as a violaceous, macular erythema with a symmetric distribution, which may progress and become poikilodermatous (atrophic with telangiectasia and pigmentary changes) and indurated (as a result of mucin deposition).

[2][3][4][5][6] Gottron's sign is erythematous or violaceous macules or plaques overlying the elbows and/or knees, and it is considered a less specific finding for DM.

[7] The macules or plaques follow the same symmetric distribution pattern as Gottron's papules but do not appear in the interphalangeal spaces.

This is a contrasting dermatologic distribution pattern to what is observed in patients with systemic lupus erythematosus.

Gottron's papules. Erythematous to violaceous raised papules overlying the metacarpal and interphalangeal joints in a patient with juvenile dermatomyositis.