Livedoid vasculopathy (LV), also known as livedoid vasculitis, presents with retiform purpura or ulcers on the lower legs that may progress to atrophie blanche (AB). LV is caused by vaso-occlusion of the cutaneous microcirculation that manifests histopathologically as hyalinization of vessels leading to fibrin thrombi. LV is a rare condition, with an estimated incidence of 1:100 000 per year and an increased incidence during summer months and during pregnancy. It tends to affect young to middle-aged adults, with a median age of onset of 30-50 years, and has a female-to-male ratio of 2-3:1.

The pathogenesis of LV is not well understood, but it is likely related to increased coagulability and/or decreased fibrinolysis. The strongest risk factor is a hypercoagulable state with laboratory evaluation positive for a known cause of thrombophilia in 40%-50% of patients in retrospective cohort studies. The second most common risk factor is connective tissue disease. LV can also be associated with monocolonal gammopathy, with hepatitis B or C, or can be idiopathic.

LV follows a chronic time course, with lesions often developing for months before a definitive diagnosis is made. In a recent case series, the median interval between symptom onset and diagnosis was 10 months and between onset and treatment was 22.5 months.

The condition is rare in children.