Mucin as a diagnostic clue in dermatopathology.

Mucins are high-molecular weight glycoproteins typically found in normal skin in small amounts. There are several reports regarding different types of cutaneous mucinosis. In this report, we discuss mucins in dermatopathology as a diagnostic clue of some well-known entities and some less frequent cutaneous diseases. We also emphasize mucin as a sign in the differential diagnosis between conditions that show histopathological overlap. Lastly, we discuss the locations and circumstances in which mucin could be considered almost normal or physiological.