Skin fibrinolytic activity in cutaneous and systemic vasculitis.

Study of involved and uninvolved skin from patients with necrotizing vasculitis revealed diminished tissue fibrinolytic activity deposition of immunoreactants in involved skin. In these patients, the depletion of tissue fibrinolytic activity is probably the result of vessel injury secondary to the local deposit of immunoreactants. In addition, there was diminished tissue fibrinolytic activity in uninvolved skin from patients with and without clinical skin involvement, unassociated with the deposition of immunoreactants. The precise mechanism for diminished tissue lytic activity in these latter patients is not known, but it may be associated with generalized activation of the coagulation and fibrinolytic mechanisms that result in local depletion of tissue fibrinolytic activity. These local changes may aggravate the clinical course of the disease as well as inhibit the healing of the lesions.