Ichthyosis is a long-term condition that results in persistently thick, dry, 'fish scale' skin. There is no cure, but symptoms are usually mild and manageable with a daily skincare routine.
There are many variations of the disease, most of which are inherited. The most common type is ichthyosis vulgaris, which affects about 1 in 250 people. The next most common type is X-linked ichthyosis, which affects about 1 in 50,00 males.
Other inherited forms of the disease are very rare and include:
- lamellar ichthyosis
- epidermolytic ichthyosis
- harlequin ichthyosis
- congenital ichthyosiform erythroderma
About the disease
Most people with ichthyosis will have inherited a particular faulty gene from their parents.
This faulty gene affects the rate at which their skin regenerates – either the shedding of old skin cells is too slow, or the skin cells reproduce at a much faster rate than they can shed old skin. Either way, this causes a build-up of rough, scaly skin.
Signs from birth
Symptoms of ichthyosis appear within the first year of life.
All types of ichthyosis cause dry, scaly skin, but this manifests slightly differently depending on which type you have.
The symptoms specific to each type of inherited ichthyosis are summarised below.
- the skin may appear normal at birth
- the skin gradually becomes dry, rough and scaly, usually before the age of one
- the bends of the elbows and knees and the face are not usually affected
- limbs may develop fine, light grey scales
- the skin on the palms of the hands and the soles of the feet may have more lines than normal and be thickened
- the child often also has eczema
- symptoms are more obvious in the winter
- the baby is covered in a thick membrane at birth, which is then shed
- scaling affects the whole body
- the child may also have drooping lower eyelids (ectropion)
- the skin is moist, red and tender at birth with blistering
- thick scaling occurs as the baby gets older
- the thickened dead skin can produce a foul-smelling skin odour
- scaling is present at or shortly after birth
- only affects males
- may be associated with testicular disease
Acquired ichthyosis tends to develop in adulthood, and is not inherited. It's usually associated with another disease such as:
- an underactive thyroid
- kidney disease
- sarcoidosis (a rare disease that causes clumps of cells to form in the organs)
- lymphoma (a type of cancer)
- HIV infection
Treatment and outlook
There is no cure for ichthyosis.
Some of the more common forms of ichthyosis are mild and will improve in the summertime.
Treatment involves moisturising and exfoliating the skin every day, to prevent dryness, scaling, cracking and the build-up of skin cells. Your dermatologist (skin specialist) will prescribe or recommend suitable moisturing creams and ointments.
You may find the following advice useful:
- apply lotions and creams to wet skin to trap in the moisture
- gently rub wet skin with a pumice stone to remove some of the thickened skin
- brush washed hair to remove scales from your scalp
People with severe ichthyosis may need to spend several hours a day caring for their skin. They may find they suffer the following problems:
- overheating, because of a reduced ability to sweat
- limited movement, because dry skin makes it too painful to move certain parts of the body
- skin infection after cracking and splitting of the skin
- impaired hearing or eyesight, if skin builds up over the ears or eyes
People with severe ichthyosis may be prescribed retinoid tablets (vitamin A) such as acitretin or isotretinoin, which reduce the growth of scaly skin but do not improve inflammation or redness. You can click on the above links for more information on the drugs.