ABSTRACT
Abnormal desquamation arises from an inability to effectively degrade the molecular components that provide cohesive force and thereby maintain tissue integrity. In such conditions corneocytes do not detach as single cells, but are shed in large clusters forming visible scales. The degree of scaling varies from severe in genetically determined disorders such as ichthyoses (which are also associated with increased thickness of the stratum corneum) to “cosmetic” dry skin. The appearance of the latter form of dry skin is a common feature in the population and is usually associated with extrinsic damage (e.g., surfactants, UV irradiation) and
following seasonal changes in the weather (cold winter conditions with a low relative humidity). Dry skin associated with the steady decline into old age (senile xerosis) reflects an increased susceptibility of the skin to extrinsic damage due to a decreased intrinsic ability to respond to challenges from the environment.
