Purpura fulminans
Purpura fulminans is a rapidly progressive syndrome of hemorrhagic skin necrosis driven by disseminated intravascular coagulation, most often triggered by fulminant sepsis such as meningococcemia or postsplenectomy pneumococcal bacteremia. Diagnosis rests on the clinical picture of expanding purpuric, necrotic plaques in a septic or asplenic patient plus laboratory confirmation of DIC, and management is emergency stabilization with empiric antibiotics, vasopressor support, and blood-component replacement for the coagulopathy.
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What this article covers
- Overview
Definition: purpura fulminans is a syndrome of rapidly progressive hemorrhagic skin necrosis caused by disseminated intravascular coagulation (DIC), in which microvascular thrombosis and consumption…
- Epidemiology
Asplenia is a major risk driver: after splenectomy, fulminant pneumococcal bacteremia with DIC (purpura fulminans) occurs more commonly than in the general population and carries a high fatality rate.
- Risk factors
Functional or anatomic asplenia: splenectomy or a functionally asplenic state (sickle cell disease) removes the primary defense against encapsulated organisms and is directly associated with fulminant pneumococcal bacteremia and DIC.
- Pathophysiology
DIC is the final common pathway: an underlying disease (severe infection or sepsis, obstetric complications, malignancy, snake bite, or a hemolytic transfusion reaction) stimulates the procoagulant…
- Clinical features
Rapidly expanding purpuric plaques with central necrosis are the defining finding: lesions begin as well-demarcated purpuric or ecchymotic patches that enlarge over hours and progress to hemorrhagic…
- Differential diagnosis
Warfarin-induced skin necrosis: onset during the first several days of warfarin therapy, often with a large loading dose, on the extremities, breasts, trunk, or penis, unlike the sepsis-associated…
- Diagnosis
The clinching diagnostic basis is rapidly progressive purpuric-to-necrotic skin lesions in a septic or asplenic patient plus laboratory evidence of DIC: thrombocytopenia, prolonged PT and aPTT, low…
- Management
First, stabilize the patient and start broad-spectrum empiric antibiotics immediately: give ceftriaxone 2 g IV every 12 hours within 30 to 60 minutes of presentation, without waiting for imaging or…
- Complications
Death from fulminant sepsis and DIC: fulminant pneumococcal bacteremia with DIC after splenectomy is often fatal, as is severe meningococcemia complicated by purpura fulminans.
- Prognosis
High mortality when triggered by fulminant bacteremia: fulminant pneumococcal bacteremia with DIC after splenectomy occurs more commonly than in the general population and is often fatal, and…
- Prevention
Vaccinate asplenic and functionally asplenic patients against encapsulated organisms: both the 23-valent polysaccharide and 13-valent conjugate pneumococcal vaccines are recommended for persons at…
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