Autoerythrocyte sensitization is the term given to an uncommon and poorly understood disorder characterized by unexplained painful ecchymoses that occur primarily on the extremities. It affects mainly women.
(See also Overview of Vascular Bleeding Disorders.)
Episodes of nonthrombocytopenic ecchymoses appear to occur spontaneously, mainly on the extremities. The ecchymoses do not occur on the back of the torso—that is, in areas that are anatomically difficult to reach. Patients have no other bleeding manifestations (eg, mucosal hemorrhage, petechiae, gastrointestinal bleeding) and tests of the coagulation system are normal.
The etiology and pathophysiology of this syndrome are poorly understood, but the lesions are likely self-induced. The syndrome typically occurs in white women who are experiencing emotional stress or who have concomitant psychiatric illness. Patients may appear indifferent to the unsightly ecchymoses but become extremely hostile if the possibility of self-inflicted trauma is suggested. Autoerythrocyte sensitization was proposed as an underlying pathophysiologic mechanism because some patients would have painful swelling after some of their own blood was injected intradermally, but this does not appear to account for the actual clinical manifestations.
Diagnosis of autoerythrocyte sensitization is by careful history, physical examination, and laboratory tests to rule out other potential bleeding disorders.
Treatment of autoerythrocyte sensitization is psychiatric therapy. If approached patiently and with time, patients often respond to behavior modification, but relapses frequently occur.