Ichthyosis - Definition, Causes, Symptoms and Treatment

Definition

The term ichthyosis is sometimes used to mean the specific condition ichthyosis vulgaris. It is a family of dermatological conditions seen in man and domestic animals. Its literal translation is fish skin, since people or animals with ichthyosis have scaly skin which can vaguely resemble the scales of a fish. Under normal circumstances, the body continuously renews its skin surface, building new skin cells and allowing older cells to be shed from the surface. Ichthyosis disrupts this balance either because too many replacement skin cells are produced or because the skin cells do not separate well from the skin surface when it is their time to drop off. The result is that skin cells accumulate into thick flakes that adhere to the body and can resemble fish scales. The condition often begins in early childhood and is usually lifelong. It is estimated to occur in 1 out of every 250 children. Boys and girls of all races and ethnicities are equally affected. Acquired ichthyosis vulgaris is very rare and occurs in adulthood.

Causes

1. Inherited forms of ichthyosis occur as a result of a genetic mutation. The mutated gene is passed on from one generation to the next.
2. It may begin in early childhood, before a child is 4 years old. In most cases one parent is affected, and each child has a 50-50 chance of being affected.
3. Leprosy, Lymphoma, AIDS, Hypothyroidism may lead to cause ichthyosis.
4. The mutated gene causes an abnormality in the normal lifecycle of skin. Whilst in most people, the growth, dying and shedding of skin happens unnoticed, people with ichthyosis reproduce new skin cells at a rate faster than they can shed it.

Symptoms

1. Ichthyosis most commonly affects the skin around the face, ears, scalp, neck, back, and the front of the arms and legs.
2. The skin where the disease is present may peel and then is replaced by thick, dark scales, which may crack and bleed.
3. Skin gradually becomes dry, rough and scaly, with most signs and symptoms appearing by the age of 5.
4. It is associated with atopic dermatitis and Palms becomes excessively lined.
5. Wax buildup in the ears, causing hearing difficulties.

Treatment

1. Alpha hydroxy acids are effective for hydrating the skin. They work by causing disaggregation of corneocytes in the lower levels of the newly forming stratum corneum.
2. Removal of scales can be aided by keratolytics which induce corneocyte disaggregation in the upper stratum corneum.
3. Creams and ointments are more effective than lotions. They are best applied to wet skin immediately after bathing.
4. If the ichthyosis leads to scratching that causes skin infections, or if body odor is a major problem, antibiotics may be needed from time to time.
5. Topical calcipotriol cream has been used with success; however, this vitamin D derivative can result in hypercalcemia when used over broad areas, especially in small children.