Crust (in the context of dermatological lesions) refers to an accumulation of:
- blood, and
- purulent exudate - which is a pus-like liquid that has seeped through the walls of intact blood vessels (usually as a result of inflammation).
Crust is included in this section because it is a type of skin lesion. Study of skin lesions is required as part of many courses in aspects of health and holistic therapies, especially bodywork therapies.