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A benign condition that primarily affects the extremities
Usually asymptomatic (apart from cosmetic concerns)
Produces a mottled, purplish discoloration of the skin in a fishnet pattern with reticulated cyanotic areas surrounding paler central cores
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Spasm or obstruction of perpendicular arterioles combined with pooling of blood in surrounding venous plexuses
Worsens with cold exposure
Improves with warming
Consider an underlying disease when
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Resembles idiopathic livedo reticularis
Has a wider skin distribution (including trunk, buttocks, and extremities)
Lesions are more irregular, broken, and circular
Presenting manifestation in 25% of patients with antiphospholipid antibody syndrome
Other underlying causes include
Antiphospholipid antibody positive Sneddon syndrome (livedo reticularis and cerebrovascular events)
Vasculitides (particularly polyarteritis nodosa)
Cholesterol emboli syndrome
Thrombocythemia
Cryoglobulinemia
Cold agglutinin disease
Primary hyperoxaluria (due to vascular deposits of calcium oxalate)
Disseminated intravascular coagulation
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Protection from exposure to cold
Vasodilators seldom indicated
If ulcerations or gangrene, exclude an underlying systemic disease