(See also Overview of Vascular Bleeding Disorders.)
Autoerythrocyte sensitization is a rare and poorly understood disorder affecting mainly women. It is characterized by local pain and burning preceding unexplained painful ecchymoses that occur primarily on the extremities.
Autoerythrocyte sensitization typically occurs in white women who are experiencing emotional stress or who have concomitant psychiatric illness. Episodes of ecchymosis are painful and can occur spontaneously or after trauma or surgery. Bruising can occur on sites of the body distant from where trauma occurs. Ecchymoses virtually never occur on the back of the torso because this area is anatomically difficult to reach.
The etiology and pathophysiology of this syndrome are poorly understood. In some women with autoerythrocyte sensitization, intradermal injection of 0.1 mL of autologous RBCs or RBC stroma may result in pain, swelling, and induration at the injection site. This result suggests that escape of RBCs into the tissues is involved in the pathogenesis of the lesion. However, most patients also have associated severe psychiatric symptoms, and some patients self-induce purpura.
Diagnosis is by careful history, physical examination, and laboratory tests to rule out other potential bleeding disorders. Tests of the coagulation system are normal.
Treatment is psychiatric therapy.