Chillblains

• Inflamed and painful purple-pink swellings on the fingers, toes or ears that appear in response to cold.
• Result from an overcompensatory cold-induced vasoconstriction of cutaneous arterioles and venules.
• Usually affect women.
• Rx = Warm housing and clothing. Nifedipine may help.

Livedo reticularis

- Marble-patterned cyanosis of the skin.

- Due to reduced arteriolar flow.

- Usually in women.

Causes:

• Physiological, i.e. cold-induced. Revesible.
• Vasculitis, e.g. SLE, PAN.
• Hyperviscosity due to cryoglobulinaemia or polycythaemia.
• Sneddon syndrome - livedo reticularis with cerebrovascular disease and circulating antiphosphlipid antibodies.

Treatment is aimed at the underlying disease.