Thus, treatment includes aggressive management of the septic state.Purpura fulminans with disseminated intravascular coagulation should be urgently treated with fresh frozen plasma (10–20 mL/kg every 8–12 hours) and/or protein C concentrate to replace pro-coagulant and anticoagulant plasma proteins that have been depleted by the disseminated intravascular coagulation process.Protein C in plasma in the steady state has a half life of 6- to 10-hour, therefore, patients with severe protein C deficiency and presenting with purpura fulminans can be treated acutely with an initial bolus of protein C concentrate 100 IU/kg followed by 50 IU /kg  every 6 hours. A total of 1 IU/kg of protein C concentrate or 1 mL/kg of fresh frozen plasma will increase the plasma concentration of protein C by 1 IU/dL. Cases with comorbid pathological bleeding may require additional transfusions with platelet concentrate (10–15 mL/kg) or cryoprecipitate (5 mL/kg).Established soft tissue necrosis may require surgical removal of the dead tissue, fasciotomy, amputation or reconstructive surgery. Prognosis
Purpura fulminans lesions, once established, often progress within 24 to 48 hours to full-thickness skin necrosis or soft-tissue necrosis. Once purpura fulminans lesions progress to full-thickness skin necrosis, healing takes between 4–8 weeks and leaves large scars.Without treatment, necrotic soft tissue may become gangrenous, leading to loss of limbs. Purpura fulminans is often accompanied by micro-vascular thrombosis and haemorrhagic infarction in other tissues, such as the lungs, kidneys, central nervous system and adrenal glands, leading to multiple organ failure, and causes initial high mortality and long-term morbidity in survivors.
In later stage lesions, there is irreversible endothelial ischaemic injury with extravasation of blood cells into the dermis and gangrenous necrosis, sometimes with secondary infection.The depletion of anticoagulant and anti-inflammatory proteins, in particular, protein C and its co-factor, protein S, may also promote thrombus formation, inhibit fibrinolysis and lead to further activation of the inflammatory pathways. Diagnosis
Early purpura fulminans lesions look similar to traumatic skin bleeds or purpuric rashes, such as immune thrombocytopenic purpura or thrombotic thrombocytopenic purpura; however, purpura fulminans will rapidly progress to necrosis whereas other purpuric rashes do not. In most cases, differential diagnoses may be distinguished from purpura fulminans by other clinical and laboratory findings.The initial appearance of purpura fulminans lesions is of well-demarcated erythaamatous lesions which progress rapidly to develop irregular central areas of blue-black haemorrhagic necrosis. Advancing areas of necrosis are often surrounded by a thin border of erythaema that fades into adjacent unaffected skin. Haemorrhage into the necrotic skin causes purpura fulminans lesions to become painful, dark and raised, sometimes with vesicle or blister (bulla) formation.The distribution of purpura fulminans lesions may be different according to the underlying pathogenesis. Purpura fulminans in severe sepsis typically develops in the distal extremities and progresses proximally or appears as a generalised or diffuse rash affecting the whole body surface. In cases of severe inheritable protein C deficiency, purpura fulminans with disseminated intravascular coagulation manifests within a few hours or days after birth.