An ulcer (from
Latin ulcus) is an open
sore of the
skin,
eyes or
mucous membrane, often caused, but not exclusively, by an initial
abrasion and generally maintained by an
inflammation, an
infection, and/or medical conditions which impede healing. In other words, it is a macroscopic discontinuity of the normal
epithelium (microscopic discontinuity of epithelium is called erosion). Other causes of skin ulcerations include pressure from various sources and venous insufficiency.
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