Gardner-Diamond syndrome is a rare clinical entity characterized by the spontaneous development of bruising and subsequent skin symptoms. An autoimmune reaction to phosphatidylserine in erythrocytes triggered by significant emotional stress or physical trauma seems to be the mechanism of disease. The diagnosis is made by injection of the patient's own red blood cells into the dermis and observation of an autoimmune reaction.
The clinical presentation of patients suffering from Gardner-Diamond syndrome (also known as autoerythrocyte sensitization syndrome) seems to start with physical trauma of the skin, seen in surgery, blunt force or accidental injuries, while emotional trauma - abortion, divorce, anxiety, etc. are also presumable triggers  . In fact, the term psychogenic purpura is used to describe typical changes seen in this condition  . The cause still remains undisclosed, but patients initially develop constitutional symptoms such as malaise and fatigue, followed by a burning, itching or stinging sensation, pain and induration of the skin with bruising   . As the lesions grow into pink or red plaques of various sizes and progress to bluish ecchymoses, a misdiagnosis for cellulitis or compartment syndrome is not uncommon, but spontaneous regression and complete resolution within one week and subsequent recurrence is the typical clinical course of lesions encountered in this condition . Skin lesions may be encountered at any site in the body, but the most common localization are the extremities . They are described in individuals of all ages, including children, and about 200 cases are documented in the literature, suggesting its very rare occurrence in medical practice  . In addition, numerous systems may be affected, including gastrointestinal (epigastric pain, nausea, vomiting, diarrhea) and vascular (subconjunctival hemorrhage, epistaxis, hematuria, menorrhagia, bleeding from the ear canal), while glomerulonephritis, stroke, and lymphoid abnormalities are extremely rare but observed findings  . Most common psychiatric disorders encountered in these patients include conversion symptoms, hysteria, depression, anxiety, and dissociative reactions  .
To make the diagnosis, it is necessary to conduct a thorough clinical and laboratory workup that will exclude other more common conditions presenting with similar symptoms. Firstly, a detailed patient history is necessary, which will identify information regarding the onset and duration of symptoms, family history of bleeding disorders and detection of possible events that induce a significant amount of stress . A meticulous physical examination should follow, and complete inspection of the skin can reveal numerous ecchymoses (either resolving or evolving) on different parts of the body . Additionally, exclusion of puncture wounds (seen in IV drug users) as the cause of skin lesions must be made   . Laboratory workup with levels of hemoglobin, hematocrit, platelet count and erythrocyte sedimentation rate within physiological levels, while prothrombin time, activated partial thromboplastin time, as well as inflammatory markers, serum electrolytes, and specific coagulation factors will also be normal . These findings will exclude many important disorders (disseminated intravascular coagulation, Henoch-Schonlein purpura, von Willebrand disease, systemic lupus erythematosus, infection, etc.) but a definite diagnosis can be obtained by injecting patient's own washed erythrocytes into the dermis, and a subsequent autoimmune reaction (to phosphatidylserine in their stroma) will cause bruising  . In addition, histopathological analysis can be performed by obtaining a sample of tissue. Extravasation of blood cells, as well as the absence of inflammatory or infectious components, is always encountered  .