Our patient had leukocytoclastic vasculitis which is a hypersensitivity vasculitis. This is a small vessel vasculitis and leukocytoclasis refers to the vascular damage caused by infiltrating neutrophils. It may be caused by by underlying collagen vascular disease, medications, malignancy or infections. In our case the patient had a previous group B strep infection as well as herpes. Both have been shown to cause leukocytoclastic vasculitis.
While leukocytoclastic vasculitis often involves the skin; it can also involve joints, the GI tract and the kidneys. Pathologically, autoantibodies including ANCA and tumor necrosis factor attract neutrophils. One type of leukocytoclastic vasculitis involves IgA deposition in the skin and joints. This is called Henoch Schonlein vasculitis. It is common in children under age 10 but also occurs in adults.
The skin rash often lasts for weeks and if it involves only skin no treatment is needed. In cases of severe joint pain colchicine can be used because it has an antineutrophil effect. Steroids and biologic immune suppression are used in serious cases of organ involvement. Our patient was treated for herpes and his rash resolved although he still had joint aches at two weeks post treatment.
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