What is Fish Scale Disease? Symptoms and Treatment

Ichthyosis vulgaris, commonly known as fish scale disease or fish scale, is a rare hereditary skin disease. Fish scale disease, which is the most common type among a group of skin diseases with more than 20 subtypes called ichthyosis, accounts for approximately 95% of all ichthyosis cases. This disease, which causes a thick, dry and scaly skin appearance, usually manifests itself from the first years of life. Mild cases of ichthyosis vulgaris may not be detected because they can be confused with very dry skin. However, in severe cases, there is a scaly skin appearance with accumulated dead skin, which reveals the disease more clearly. There is no definitive treatment for this disease, as it is a genetic disease. Current treatment methods are generally aimed at improving the appearance of the skin and relieving the symptoms.

What is Fish Scale Disease?

The question of what fish scale disease or ichthyosis vulgaris is can be answered as a genetic disease that causes an appearance similar to fish scales on the skin. Although the majority of fish scales are genetically inherited, they can very rarely occur later in development. It is thought that the main cause of acquired fish skin diseases is the mutation of the relevant genes.

The main feature of the disease is that the entire skin surface is covered with scale-like skin layers formed by dead skin. The layers in question are mostly brown in color. However, some patients may also experience a white or gray appearance. Thickened and dried skin causes severe itching. In addition, fish scale disease affects the person more severely in the winter months because the weather is colder and drier.

Sweating is not possible in fish scale patients due to skin lesions. The majority of ichthyosis vulgaris cases are mild. Therefore, it can be confused with skin diseases such as allergies or eczema. While scale-like dead skin layers are commonly seen on the legs in patients, flaking may also occur on the arms, hands and other parts of the body. Most patients have deep lines on the palm.

Causes of Fish Scale Disease

The most common cause of ichthyosis vulgaris is heredity. However, fish scale disease may also occur due to genetic mutations that develop later. In fish scale patients, although the cells in the skin multiply at a normal rate, they cannot be removed from the skin surface in a healthy way.

Accordingly, dead skin that is not shed quickly enough turns into layers and forms scale-like structures on the skin surface. Fish scale disease genes, which can be genetically inherited from both parents, do not require the mother or father to be sick. There is a possibility of the disease being seen in the children of parents who are carriers of this gene.

The disease is autosomal semidominant, that is, semi-dominant inheritance. The presence of a single disease gene within a chromosome pair results in a mild version of the disease. If the disease or mutation is found in both genes, a moderate or severe version of the disease is encountered. Since it is a rare disease, the probability of inheriting the fish scale gene from both parents is very low, except through consanguineous marriage, so mild forms of the disease are much more common.

Another factor that is thought to be among the potential causes of ichthyosis vulgaris is mutations in the uterus. When such a situation occurs in the unborn baby, it is thought that the protein called filaggrin, which helps to form the outermost layer of the skin and shed dead skin, is missing. Fish scale diseases caused by such genetically based causes manifest themselves from the first years of life.

Fish scale disease seen in adults is acquired (acquired). There are studies showing that some diseases such as various types of cancer, kidney failure , leprosy, sarcoidosis, HIV and AIDS can lead to later developing fish scales. It is also emphasized that, although rare, some medications used may cause fish scale disease.

Fish Scale Disease Symptoms

The symptoms are almost the same in both acquired and genetic fish skin disease. Main symptoms include:

• Rough and dry skin structure (xerosis)
• Itching on the skin
• Disease-specific appearance that is usually not present at birth and begins between the second month and five years of age
• Chicken skin appearance on the skin (follicular hyperkeratosis)
• Layers of dead skin concentrated on the legs, arms, scalp, and various parts of the face and trunk
• It is most visible on the outer surface of the arms and legs, and the arm and leg folds are preserved.
• Hard bumps similar to acne spots on the arms, thighs, and buttocks
• Inability to sweat enough, resulting in problems with the body’s heat balance in severe cases
• Distinct skin lines on palms and soles (hyperlinearity)
• Formation of cracks on the skin and related infections

The severity of disease symptoms is affected by environmental conditions as well as the number of defective genes. People living in hot and humid climates do not experience very severe symptoms. However, as skin dryness increases in cold and arid climates, the symptoms may be much more severe. However, people with fish scale disease are also more likely to develop diseases such as dermatitis, eczema (atopic dermatitis), allergic rhinitis, allergic asthma and food allergies.

Fish Scale Disease Treatment

Patients with a skin appearance similar to fish scale disease may experience simple skin dryness and related flaking problems. Since these two conditions can cause very similar symptoms, treatment for dry skin is often administered before genetic testing is sought. If no improvement can be achieved in the fish scale appearance seen in children by using a suitable moisturizer twice a day, the physician may refer to genetic tests with the suspicion of ichthyosis vulgaris.

If there is a family member with fish scale disease, the doctor should be informed about this. In addition, information such as other diseases the patient has, medications used and how long the symptoms have persisted can also be very decisive for diagnosis and treatment. Therefore, it is very important to take a detailed medical history of the patient. If deemed necessary by the physician, a small sample of the skin can be taken through biopsy and sent to the laboratory for examination under a microscope. Unfortunately, there is no definitive treatment to prevent the condition in patients diagnosed with genetic ichthyosis vulgaris as a result of these studies. However, with some medical treatments and home care practices, symptoms and complaints related to the disease can be significantly alleviated.

Some medications and creams may be prescribed by the physician to moisturize the skin, remove dead skin and relieve itching problems. Regular use of these helps reduce skin lesions. However, practices such as frequent bathing, using a bath sponge or scrub to cleanse the skin of dead skin, and applying moisturizing cream to the skin after bathing are very effective in combating dead skin layers caused by the disease.

Using air humidifiers at home, especially during winter months and in arid regions, can be effective in reducing skin dryness. If symptoms such as eczema and allergies are observed in addition to the disease, a separate treatment plan should be created for these.

Dead skin layers formed on the skin due to genetic in children and acquired fish scale disease in adults can multiply, crack and develop infection if sensitivity is not shown. Therefore, if you or your child are experiencing skin lesions that resemble fish scales, it would be beneficial to consult a dermatologist and get an opinion on the causes of this condition.