Thrombosis in the perforasome in idiopathic purpura fulminans with anti-protein S antibodies: Anatomical and clinical evidence to improve management.

Idiopathic purpura fulminans (IPF) is a rare and severe form of purpura fulminans caused by acquired protein S deficiency. It can lead to severe thrombotic complications, such as large skin necrosis and amputation. The lesions almost exclusively affect the lower limbs, and their distribution is similar among patients with IPF, unlike classical purpura fulminans lesions. Our hypothesis is that vascular structures called perforasomes may be involved in IPF, possibly caused by protein S deficiency. We analyzed all case reports and case series published in the literature that provided sufficient data for an anatomical study of limb injuries. For precise localization of areas of necrosis, we examined each case using descriptions and images to determine whether they overlapped with vascular territories that include perforasomes. We analyzed twelve cases from the literature and identified six vascular territories: the anterolateral, anteromedial, and posterior territories of the upper leg, as well as the anterolateral, anteromedial, and posterolateral territories of the lower leg. For each territory, we described the most probable vascular damage and the corresponding perforasome. IPF is a complex multifactorial disease in which a direct involvement of perforating arteries may be suspected and taken into account in the surgical of lesions.