Psychogenic Purpura
PRACTICE POINTS
- Psychogenic purpura is a rare vasculopathy characterized by painful recurrent episodes of purpura. It is a diagnosis of exclusion that may manifest with signs similar to cutaneous small vessel vasculitis.
- Awareness of this condition could help prevent unnecessary diagnostics, medications, and adverse events.
Histopathology typically reveals superficial and deep perivascular inflammation with extravasated erythrocytes. Direct immunofluorescence is negative for vasculitis.8 Diagnostics and laboratory findings for underlying systemic illness are negative or noncontributory. Cutaneous injection of 1 mL of the patient’s own washed erythrocytes may result in the formation of the characteristic painful plaques within 24 hours; however, this test is limited by lack of standardization and low sensitivity.3
Psychogenic purpura may share clinical features with cutaneous small vessel vasculitis, such as HSP or urticarial vasculitis. Some of the findings that our patient was experiencing, including purpura, arthralgia, and abdominal pain, are associated with HSP. However, HSP typically is self-limiting and classically features palpable purpura distributed across the lower extremities and buttocks. Histopathology demonstrates the classic findings of leukocytoclastic vasculitis; DIF typically is positive for perivascular IgA and C3 deposition. Increased serum IgA may be present.9 Urticarial vasculitis appears as erythematous indurated wheals that favor a proximal extremity and truncal distribution. They characteristically last longer than 24 hours, are frequently associated with nonprodromal pain or burning, and resolve with hyperpigmentation. Arthralgia and gastrointestinal, renal, pulmonary, cardiac, and neurologic symptoms may be present, especially in patients with low complement levels.10 Skin biopsy demonstrates leukocytoclasia that must be accompanied by vessel wall necrosis. Fibrinoid deposition, erythrocyte extravasation, or perivascular inflammation may be present. In 70% of cases revealing perivascular immunoglobulin, C3, and fibrinogen deposition, DIF is positive. Serum C1q autoantibody may be associated with the hypocomplementemic form.10
The classic histopathologic findings in leukocytoclastic vasculitis include transmural neutrophilic infiltration of the walls of small vessels, fibrinoid necrosis of vessel walls, leukocytoclasia, extravasated erythrocytes, and signs of endothelial cell damage.9 A prior punch biopsy in this patient demonstrated rare neutrophilic nuclear debris within the vessel walls without fibrin deposition. Although the presence of nuclear debris and extravasated erythrocytes could be compatible with a manifestation of urticarial vasculitis, the lack of direct evidence of vessel wall necrosis combined with subsequent biopsies unequivocally ruled out cutaneous small vessel vasculitis in our patient.
Psychogenic purpura has been reported to occur frequently in the background of psycho-emotional distress. In 1989, Ratnoff11 noted that many of the patients he was treating at the University Hospitals of Cleveland, Ohio, had a depressive syndrome. A review of patients treated at the Mayo Clinic in Rochester, Minnesota, illustrated concomitant psychiatric illnesses in 41 of 76 (54%) patients treated for PP, most commonly depressive, personality, and anxiety disorders.3
There is no consensus on therapy for PP. Treatment is based on providing symptomatic relief and relieving underlying psychiatric distress. Block et al12 found the use of selective serotonin reuptake inhibitors, tricyclic antidepressants, and psychotherapy to be successful in improving symptoms and reducing lesions at follow-up visits.
