What is a fissure?

A fissure is defined as a tear or crack-like sore in the skin. This description accurately captures the nature of a fissure, which usually occurs in areas where the skin is thin and can become damaged or where excessive stretching occurs, leading to a split. Fissures are often painful due to their exposure to external irritants and the underlying tissue being affected. This clinical term is commonly used in various medical contexts, particularly in dermatology and gastroenterology.

The other options describe different medical conditions or lesions. For instance, a localized area of pus refers to an abscess, which involves infection and accumulation of pus rather than a simple tear in the skin. A closed comedo, also known as a whitehead, is a type of acne lesion caused by clogged hair follicles, and it has no correlation with fissures. Lastly, a small elevated lesion on the skin refers to a papule, which is distinctly different in presentation from a fissure, as it represents a raised area rather than a crack or tear. Thus, the characteristics of a fissure align specifically with its definition as a tear or crack in the skin.