Ichthyosis vulgaris
Overview
Sometimes called fish scale disease or fishskin disease, ichthyosis vulgaris is an inherited skin disorder that causes dead skin cells to accumulate in thick, dry scales on the skin's surface. These scales can be present at birth, but usually first appear in early childhood. Sometimes ichthyosis vulgaris disappears entirely for most of the adult years, only to return later. Though most cases are mild, some cases of ichthyosis vulgaris are severe. No cure has been found and treatments are directed at controlling the signs and symptoms.
Symptoms
Ichthyosis vulgaris is characterized by: Very dry, scaly skin. Tile-like scales that are small, polygonal in shape. Scales that range in color from white to dirty gray to brown. People with darker skin tend to have darker colored scales. Flaky scalp. In severe cases, deep painful cracks in the palms and soles. The scales usually appear on the elbows and lower legs and may be especially thick and dark over the shins. Though most cases of ichthyosis are mild, some can be severe. Symptoms usually worsen or are more pronounced in cold, dry environments and tend to improve or even resolve in warm, humid environments. Other less common forms of ichthyosis include: Lamellar ichthyosis. This severe form of the disease is present at birth and lasts throughout life. Infants with lamellar ichthyosis are born encased in a filmy membrane that's shed after 10 to 14 days, revealing skin that's covered in scales. The scales can range from fine and white to thick and dark and generally occur over the entire body, although they may be larger on the legs. Lamellar ichthyosis can be extremely disfiguring and may cause great psychological suffering for children and adults with the disease. X-linked ichthyosis. Starting soon after birth, this type of ichthyosis occurs only in males. The noticeable, dirty-brown scales that characterize this skin disease are most pronounced on the back of the neck, arms and behind the knees. Symptoms generally don't improve with age. Epidermolytic hyperkeratosis. This extremely rare form of ichthyosis is usually present at birth and begins with blistering skin. In time, the skin peels away in large sheets and becomes rough or wart-looking. It's most pronounced on the knees, elbows, wrists and other flexural areas.
Causes
The skin is an endlessly renewable organ. New skin cells at the base of the epidermis push toward the surface of the skin, where they eventually shrink, flatten and die. These dead skin cells flake off every day and are continuously replaced by more cells. Ichthyosis, however, disrupts this pattern. It occurs when the production of skin cells is too fast or the skin's natural shedding process is too slow. This causes dead skin cells to collect into thick flakes that stick to the outer surface of skin. These thick flakes can resemble fish scales. Most often, ichthyosis is inherited in an autosomal dominant pattern, which means that a child has to inherit only one copy of the affected gene to develop the disease. Children with the inherited form of the disorder usually have normal skin at birth but develop scaling and roughness during the first few years of life. At times, ichthyosis vulgaris may disappear during the adult years, only to return later. Ichthyosis not caused by genetics, referred to as acquired ichthyosis, is very rare. This type usually manifests in adulthood and is usually associated with other internal diseases, such as cancer, thyroid disease or chronic renal failure.
Diagnosis
A doctor can often make a diagnosis by examining the skin and the characteristic scales. If there's any doubt, he or she may perform other tests, such as a skin biopsy. This may be necessary to rule out other causes of dry, scaly skin. To diagnose ichthyosis, he or she also takes into account: Personal and family history of ichthyosis Age when ichthyosis first started Presence of other skin disorders
Treatment
There is no cure for ichthyosis. The main goal of treatment is to moisturise and exfoliate. This helps prevent dryness, scaling, cracking and build-up of skin. People with ichthyosis need to bathe, moisturise and exfoliate their skin on a daily regular basis. Your dermatologist may prescribe or recommend moisturising creams and ointments to keep the condition under control. In severe cases they may prescribe oral retinoids such as acitretin or isotretinoin. This can help to reduce scaling. Oral antibiotics may be prescribed if secondary infection occurs. The following skin care tips may help: Apply lotions and creams to wet skin to trap in the moisture (within 3 minutes of showering/bathing) Rub gently a pumice stone on wet skin to help remove thickened crusty skin Brush washed hair to remove scales from scalp Lanolin creams and products containing urea, lactic acid and other alpha hydroxy acids may help to exfoliate and moisturise skin