Final answer:
Petechiae are tiny red or purple spots on the skin caused by minor bleeding under the skin from damaged blood vessels, often as a result of inflammation or other underlying conditions like vasculitis.
Step-by-step explanation:
Petechiae are defined as small red or purple spots on the skin that result from blood leaking out of damaged vessels. These are minor hemorrhages that can occur due to various conditions, one of which is vasculitis. When vasculitis occurs, blood may leak from the damaged vessels, forming these distinctive spots. Vasculitis is an inflammation of the blood vessels that causes changes in the walls of blood vessels, including thickening, weakening, narrowing, and scarring.
Petechiae are different from other types of skin lesions such as large, raised, and itchy skin rashes—which could indicate conditions like eczema—and are not blisters filled with fluid nor scaly, dry patches on the skin. In contrast, petechiae are pinpoint, round spots that appear on the skin as a result of minor bleeding.
Inflammation and Skin Lesions
Inflammation is a key response of the body's immune system that can lead to various skin appearances. When inflammation occurs, the affected area may become red, warm, and painful, and the skin condition eczema is an allergic reaction that manifests as dry, itchy patches of skin, often accompanied by swelling and flaking.