Gardner-Diamond syndrome (GDS) is a rare condition characterized by episodes of unexplained, painful bruising that mostly occurs on the arms, legs, and/or face. It is most common in Caucasian women who have mental illness or emotional stress. Symptoms typically include the formation of multiple, small, purple bruises that may be associated with burning, redness and swelling. Most affected people report that the bruising occurs either spontaneously, or some time after trauma or surgery at other sites of the body. The cause of GDS is poorly understood. Management typically involves psychiatric treatment.

Episodes of bruising may begin with sensations such as burning, stinging or pain, and may be accompanied by a general feeling of malaise or fatigue. This may be followed by warmth, puffiness, redness and/or itching over the affected area. In some cases, episodes may also be accompanied by fever, headache, or gastrointestinal symptoms. Sometimes, pain and swelling is severe enough to cause immobilization of the affected body part. People have reported that the pain generally subsides when the bruises appear.

Bruises typically go away in approximately 7-10 days. However, relapses and remissions of bruising episodes can last for many years. In some cases, symptoms of the condition persist and may worsen. Subsequent episodes are most likely to occur after some sort of physical trauma or stress.

There are no specific laboratory tests that can confirm the diagnosis of Gardner-Diamond syndrome (GDS), but various tests may be used to rule out other conditions. The diagnosis may be considered based on the presence of symptoms, when all other causes of bleeding have been ruled out (including the use or misuse of various medications that may be associated with bleeding). A detailed psychiatric evaluation is of huge importance if GDS is suspected, with information concerning how the person has responded to major stressful events in his or her life (such as fetal losses, death in the family, divorce, loss of income). While the underlying cause of GDS is unknown, an abnormal psychiatric history is virtually always present.

It has been proposed that certain medications used to alter the tonus of the capillaries (how they contract), the permeability of the vessels, and/or the flowing properties of the blood may be useful for some people.

Symptomatic therapy may be helpful for severe, general symptoms. Several approaches including antihistamines, corticosteroids, antidepressants, hormones, and vitamins have had variable success.

In some cases, symptoms of GDS may persist and even worsen.The onset of new lesions is most probable after physical trauma or stress.