Chilblain lupus erythematosus was initially described by Hutchinson in 1888 as an uncommon manifestation of chronic cutaneous lupus erythematosus. Chilblain lupus erythematosus is characterized by a rash that primarily affects acral surfaces that are frequently exposed to cold temperatures, such as the toes, fingers, ears, and nose. The rash is defined by oedematous skin, nodules, and tender plaques with a purple discoloration. Its pathogenetic factors include cold-induced vascular thrombosis, blood stasis, and impaired microcirculation. Chilblain lupus has been linked to anti-Ro antibodies.

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Wiki: Chilblain lupus