Bruising of the hands and arms may result from a condition called actinic purpura or Bateman purpura. It involves flat, purple blotches (macules) that darken before gradually fading. Actinic purpura occurs due to sun damage that weakens the blood vessels and appears most often in elderly and light-skinned individuals.  

Although this condition closely resembles standard bruising, there are a few key differences. For example, bruises associated with actinic purpura do not usually result from a significant known injury to the skin. Rather, they may occur from trauma so slight that the patient is not even aware of it. The bruises of actinic purpura are not typically tender and do not display the normal color changes of bruises over time (reddish to purple to greenish to brown). Instead they tend to remain purplish until they gradually fade away, leaving an area of depigmentation or a whitish scar. Finally, the bruises of actinic purpura tend to last longer than standard bruises and may be present for up to a few weeks after they first appear.

With actinic purpura, bruising usually appears on the back of the hands and forearms but may also affect the face and neck. The skin appears sun-damaged, thin and wrinkled. In most cases, the bruising is relatively harmless and will disappear on its own. However, in some cases the bruising may indicate a serious, underlying condition, such as low levels or abnormal function of platelets, which help the blood clot following an injury. Patients should consult a physician if they experience any of the following:

• Bruising that occurs suddenly without a previous history of bruising, especially soon after beginning a new medication
  
  
• Frequent bruising accompanied by abnormal bleeding elsewhere, such as from the nose, gums or urinary or intestinal tracts
  
  
• Unusually large or painful bruises, especially if they appear to develop for no reason

In most cases, bruising that is characteristic of actinic purpura can be identified through a visual examination by a physician, which may include a physical examination. However, in some cases additional testing may be performed to confirm the diagnosis and rule out other conditions. Such tests may include:

• Blood tests. Several blood tests may be performed including:
  
  
• • Coagulation studies. Tests that determine how well a patient’s blood clots.
    
    
  • Complete blood count. A series of tests to look for abnormalities in the blood that may indicate the presence of disease.
    
    
  • Platelet count. Measures the number of platelets in blood. Platelets are necessary for normal blood clotting.
    
    
• Liver function tests. A series of tests that determine how effectively a patient’s liver functions.
  
  
• Stool guaiac test. Checks for the presence of hidden (occult) blood in the stool.
  
  
• Urine tests. A series of chemical and microscopic tests to look for abnormalities in the urine that may indicate the presence of disease.

Patients who experience bruising of the hands and arms due to actinic purpura are likely to continue to have them throughout their lifetime.