THE interrelationship of psychological factors and organic disease has been frequently described. These interrelationships are particularly intriguing when the physical manifestation of disease appears to be a direct translation of some psychological pathology in the manner of a conversion reaction. This communication presents c;omocal data that suggest such a relationship between conversion reactions and the production of ecchymosis in patients with autoerythrocyte sensitization. This disease is a chronic purpuric state affecting adult and adolescent females, manifested by episodes of painful spontaneous bruising.1 The onset of the spontaneous bruise or ecchymosis is stereotyped. The patient's attention is drawn to a new lesion by a sudden pain described as sharp, stabbing, stinging, or burning. A lump then appears followed within a few minutes by an erythema. Within an hour or so an ecchymosis spreads from the periphery of the erythematous area. Although the erythema usually lasts no more than a