Ichthyosis, fish skin

Ichthyosis or fish skin (new spelling: fish skin) is a skin disease in which the skin is very dry and flaky and forms scales. Ichthyosis should not be confused with eczema or psoriasis. Ichthyosis vulgaris is the most common hereditary variant and can occur in young children. The skin disease is especially annoying because it scares other people away. Treatment is available, but it cannot cure the disease. Ichthyosis is also called the scaling disease.


Ichthyosis (sometimes written as ichthyosis) is often hereditary. If one of the parents has this disease, there is a 50 percent chance that the child will also get it. This is a fairly high percentage. Certain variants are only passed on to sons through the mother. The mother is a carrier of the gene, the son gets the disease. In some cases, the disease only manifests itself when both parents are carriers of the abnormal gene. Moreover, someone who carries the abnormal gene does not necessarily develop the disease themselves. Sometimes ichthyosis develops in adulthood. Heredity then plays no role. The precise cause is then unclear. It often occurs in people who already have very dry skin.

Symptoms: scaly skin

In ichthyosis, the keratinization of the upper layer of cells is disturbed. Cell division takes place in the lower parts of the epidermis (the top layer of the skin). In this way the skin grows. The new cells are pushed upwards because new cells are formed underneath. During this upward movement, the cells lose their nucleus and start to keratinize. The outer layer of the skin now consists of a stratum corneum. New horn is continuously formed on the inside of this layer, while on the outside the layer keeps flaking off. Because the keratinization is disturbed, extreme flaking of the skin occurs. The underlying skin can sometimes look very red. Scales often develop due to disturbed keratinization.
On the hands and feet we see extra keratinization, calluses develop. Very often, cracks occur that can be located on the thumb or fingertips, but also on the foot. Fissures or fissures are cracks in the skin that occur in areas where there are calluses. Blisters can also form on the skin. Sometimes there is itching. Ichthyosis can progress to eczema, but ichthyosis can also develop after a period of eczema. Some people with ichthyosis have hay fever or another form of allergy. Eczema, allergy, hay fever and ichthyosis often occur simultaneously or alternate.
Ichthyosis is not always present at birth but often occurs in the first months. This starts with a lighter flaking. The baby often first suffers from a mountain (eczema) on the head. It becomes clear that the baby is sensitive to skin diseases or skin abnormalities. In some cases, ichthyosis only occurs late in life, but can be preceded by very dry skin or flaking for years.

Ichthyosis vulgaris

The most common variant of this disease is ichthyosis vulgaris. This form occurs just as often in boys as in girls and is transmitted by one of the parents. Often the parent with the abnormal gene also has the disease themselves. Almost all cases of ichthyosis consist of the vulgaris form.

Other forms of ichthyosis

There are other forms of ichthyosis. These sometimes only occur in the male sex, such as the X-linked variant. The mother is then a carrier of the gene and passes it on to her son. Mother is not affected by the disease and shows no symptoms. Lamellar ichthyosis is only manifested when both parents are carriers of the gene. If only one of the parents is a carrier of the gene, this gene will be passed on to the child, but the child will not develop the disease. However, the child can transmit the disease to its offspring if they have a child with another carrier of the gene. Lamellar ichthyosis often occurs at birth and can be serious right away. The lower eyelids are sometimes turned outward.


The doctor (dermatologist) will investigate whether this is ichthyosis. This can be done through a skin biopsy, where a small piece of skin is removed for further examination. Genetic research can also be performed. The disease cannot be cured, but it can be treated as best as possible. This is done by applying a greasy cream several times a day. The dermatologist can prescribe this. Do not use hormone ointments intended for eczema. Acitretin, a substance that is very similar to vitamin A, often produces good results and can be used with certain variants. A solution with urea also gives good results. By applying urea, water is better absorbed by the skin.

read more

  • Eczema and its treatment
  • Hay fever or pollen allergy
  • Cracks and fissures
Scroll to Top