Ichthyosis Vulgaris

Keeping the skin well moisturized is one of the best treatments for ichthyosis vulgaris.

Ichthyosis vulgaris is a rare inherited skin condition that is characterized by extremely dry skin (xerosis) involving most of the skin surface. Ichthyosis vulgaris produces large scales in the skin that can resemble fish scales, hence the term ichthyosis. Vulgaris simply means the common form. Other types of ichthyosis are even rarer. Patients with this condition have a defective skin barrier, which permits the evaporation of water at an elevated rate.

An inherited genetic defect, a mutation, affecting a giant protein called filaggrin causes ichthyosis vulgaris. One inherits the defective gene from one's parents and may be produced by one or more mutations in the profillagrin gene produced early in fetal development. It is expressed in an autosomal dominant fashion, which means that all that is necessary to have the disease is a single defective copy of the gene that codes for filaggrin. Since this protein plays a major role in the maintenance of the correct level of hydration in the skin, affected patients have difficulty retaining water in the superficial layers of the skin.

A significant number of patients with atopic dermatitis, asthma, and hay fever share mutations in this gene, as well.

Since this is an inherited condition, it is not contagious and cannot spread from person to person.

The most significant finding, which is ultimately diagnostic, is the presence of very dry skin over most of the skin surface. The abnormal appearance of the skin is diagnostic of ichthyosis vulgaris. This dryness appears as a flaky scalp; deep, painful cracks in the skin; and rather small, dry scales that seem to spare moist areas like the armpits and groin, as well as other flexural areas. The scales are brown, gray, or white.

The characteristic appearance is usually absent at birth but becomes obvious as the child ages.

Since ichthyosis vulgaris is relatively rare (one in 250-1,000 children), only physicians specializing in the skin (dermatologists) or genetic defects are equipped best to diagnose and treat this condition. Doctors often suspect a diagnosis purely based on the skin's appearance.

Evidence of other blood relatives with ichthyosis would support the diagnosis. Occasionally, it may be necessary to examine affected skin with a biopsy using light microscopy and even electron microscopy.

Other types of ichthyosis can be confused with ichthyosis vulgaris.

Since the condition is rare, there are few well-controlled treatment trials. There is no way of replacing the defective filaggrin molecule.

Living in a humid environment is very helpful in controlling the disease. Patients usually do well in places like Southeast Asia as opposed to Northern Europe.

Using emollients on the skin that tend to suppress the evaporation of water can be very helpful. Effective emollients usually come in jars and are thick and do not flow. Topical medications that contain 10% lactic acid, 10% urea, and/or 10% glycerol (AmLactin, Lac-Hydrin, Lactinol, Lactinol-E, LactiCare, Ureacin-10, Aqua Care) can be very helpful, as well.

As most of the topical medications recommended for the control of this condition are available without a prescription, people can treat their mild disease without physician supervision. It is prudent to see a physician specialist to obtain an accurate diagnosis and follow medical advice.

There are no dietary manipulations likely to affect this condition

Ichthyosis vulgaris may be either mild or severe depending on the precise genetic defect (more than one mutation affecting filaggrin production), as well as ambient environmental factors (average relative humidity and temperature). The mild disease has an excellent prognosis, whereas severe disease may be difficult to control.

The major complications that occur are due to the damage that is produced by the excessive dryness characteristic of this condition. Dry skin is exceptionally susceptible to irritation. Irritated skin is red and itchy. Scratching skin predisposes it to skin infections.

In addition, there seems to be a predilection for the development of eczema (atopic dermatitis) and other allergic conditions, including asthma and hay fever. Currently, medical professionals do not understand the reason for this relationship.

Once conception occurs, it is not possible to prevent the development of ichthyosis at this time.

The following are ichthyosis support groups on the Internet:

The Foundation for Ichthyosis & Related Skin Types (FIRST)

Ichthyosis Support Group