Ecchymosis, commonly known as a bruise, is caused by blood leaking from damaged blood vessels, typically capillaries, into the tissues under the skin.
Essentially, when small blood vessels break near the surface of the skin, blood escapes and becomes trapped. This trapped blood is what causes the discoloration we recognize as a bruise. Several factors can contribute to this rupture:
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Trauma: This is the most common cause. Any impact, bump, blow, or injury to the skin can damage underlying capillaries.
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Medications: Certain medications, such as blood thinners (anticoagulants like warfarin or aspirin) can increase the risk of bruising by making it easier for blood vessels to bleed. Corticosteroids can also thin the skin over time, making capillaries more susceptible to damage.
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Medical Conditions: Some medical conditions can increase bruising, including:
- Clotting disorders: Conditions that affect the blood's ability to clot normally (e.g., hemophilia, von Willebrand disease)
- Thrombocytopenia: Low platelet count, which impairs blood clotting.
- Vasculitis: Inflammation of blood vessels, making them fragile.
- Liver disease: Can affect blood clotting factors.
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Nutritional Deficiencies: Lack of certain vitamins (e.g., Vitamin C, Vitamin K) can weaken blood vessels and increase bruising.
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Aging: As we age, our skin becomes thinner and blood vessels become more fragile, increasing susceptibility to bruising.
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Strenuous Exercise: Particularly exercises that involve heavy lifting or high impact, can sometimes cause small blood vessel ruptures.
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Sun Damage: Long-term sun exposure can weaken the skin and blood vessels.
The color of a bruise changes over time as the body breaks down the trapped blood. It typically starts as reddish-blue, then turns bluish-purple, then greenish, and finally yellowish before fading away.
