Purpura Fulminans Triggered by the Formation of Anti-Endothelial Autoantibodies in a Patient with Chronic Lymphocytic Leukemia

Purpura fulminans (PF), a life-threatening disorder characterized by
cutaneous microvascular thrombosis with secondary hemorrhagic infarction, is
a rare complication of sepsis and may also be caused by severe protein C or
protein S deficiency.
Here, we describe the case of a 58-year-old man who developed PF in close
association with the onset of chronic lymphocytic leukemia (CLL). PF initially
manifested with an ecchymosis of the right upper leg in the absence of sepsis
or disseminated intravascular coagulation. PF was likely triggered by antiendothelial
IgG autoantibodies functionally interfering with the anticoagulant
protein C-protein S-thrombomodulin system on EA.hy926 endothelial cells
in a modified thrombin generation assay. Although plasma exchange and
immunosuppressive therapy with cyclophosphamide were temporarily effective,
PF eventually progressed and the patient died from septic shock during
treatment-associated neutropenia.
In rare occasions, CLL may be associated with autoimmune-mediated PF
requiring prompt diagnosis and aggressive multimodal therapy.