Bruising

Bruising (bruise), also called a contusion or ecchymosis, is a kind of injury to biological tissue in which the capillaries are damaged, allowing blood to seep into the surrounding tissue. It is usually caused by blunt impact. Bruises often induce pain but are not normally dangerous. Sometimes bruises can be serious, leading to other more life threatening forms of hematoma, or can be associated with serious injuries, including fractures and internal bleeding. Minor bruises are easily recognized by their characteristic blue or purple color in the days following the injury.

Causes
• Local injury or trauma
• Allergic reaction
• Autoimmune disorders
• Viral infection or illness affecting blood coagulation
• Thrombocythemia
• Medical treatment, including radiation and chemotherapy
• Bruise (ecchymosis)
• Birth (petechiae in the newborn)
• Aging skin (ecchymosis)
• Idiopathic thrombocytopenic purpura (petechiae and purpura)
• Henoch-Schonlein purpura (purpura)• Leukemia (purpura and ecchymosis)
• Drugs
• Anticoagulants such as warfarin or heparin (ecchymosis)
• Aspirin (ecchymosis)
• Cortisone (ecchymosis)
• Septicemia (petechiae, purpura, ecchymosis)
• Violent vomiting or coughing (petechiae)