Ichthyosis

Overview :

The ichthyoses are a group of skin diseases caused by an abnormality in skin growth that results in drying and scaling. There are at least 20 types of ichthyosis. Ichthyosis can be more or less severe, sometimes accumulating thick scales and cracks that are painful and bleed. Ichthyosis is not contagious. Some forms of ichthyosis are inherited while others are acquired in later life as a symptom of systemic disorders.

The most common form of ichthyosis, accounting for 95% of all cases of ichthyosis, is called ichthyosis vulgaris (vulgaris is the Latin word for "common"), and occurs in approximately one person in every 250. It is inherited in an autosomal dominant manner. The most rare types of ichthyosis occur in fewer than one person in one million and are inherited in an autosomal recessive manner. Ichthyosis occurs regardless of the part of the world the child is from, or the ethnic background of the parents.

Acquired ichthyosis is extremely rare; neither its incidence in the United States nor its incidence in the rest of the world are known as of 2003.

Both inherited and acquired ichthyoses affect males and females equally.