Abstract
An ecchymosis is a subcutaneous spot of bleeding (from extravasation of blood) with diameter larger than . It is similar to (and sometimes indistinguishable from) a hematoma, commonly called a bruise, though the terms are not interchangeable in careful usage. Specifically, bruises are caused by trauma whereas ecchymoses, which are the same as the spots of purpura except larger, are not "necessarily" caused by trauma, often being caused by pathophysiologic cell function, and some diseases such as Marburg virus disease.
A broader definition of ecchymosis is the escape of blood into the tissues from ruptured blood vessels. The term also applies to the subcutaneous discoloration resulting from seepage of blood within the contused tissue.
Signs and symptoms
Hematomas can be subdivided by size. By definition, ecchymoses are 1 centimeter in size or larger, and are therefore larger than petechiae ( less than 2 millimeters in diameter) or purpura (2 millimeters to 1 centimeter in diameter). Ecchymoses also have a more diffuse border than other purpura.
Cause
There are many causes of subcutaneous hematomas including ecchymoses. Coagulopathies such as Hemophilia A may cause ecchymosis formation in children. The medication betamethasone can have the adverse effect of causing echhymosis.
Etymology and pronunciation
The word "ecchymosis" (; plural "ecchymoses", ), comes to English from New Latin, based on Greek ἐκχύμωσις "ekchymōsis", from ἐκχυμοῦσθαι "ekchymousthai" "to extravasate blood", from ἐκ- "ek-" (elided to ἐ- "e-") and χυμός "chymos" "juice". Compare "enchyma", "tissue infused with organic juice"; elaboration from chyme, the formative juice of tissues.