What is psoriasis in children?
Psoriasis is a chronic skin disease in which red, scaly patches typically arise on the skin. It is fairly common, in both adults and children. The way psoriasis presents in children is often slightly different from adults, and the treatment sometimes differs too.
What does psoriasis in children look like?
As in adults, psoriasis in children can take several forms.
Chronic plaque psoriasis
Red, scaly patches on the skin, varying in size from a few millimetres to many centimetres. Classic sites are the elbows and knees, but the patches can arise anywhere. Psoriasis on the face is fairly rare, but occurs somewhat more often in children than in adults. Sometimes the patches have a slightly ring-shaped appearance. The patches sometimes itch, but any itch is as a rule much less intense than with, for example, eczema.
Guttate psoriasis
Very many small round psoriasis spots spread mainly over the trunk. It often arises after a (throat) infection, and this form is seen relatively often in children.
Flexural psoriasis
Psoriasis in the folds (inverse psoriasis) is seen in the groin, armpits and the cleft of the buttocks. The skin usually does not scale but is pink, smooth and shiny. This form too is seen relatively more often in children.
Other forms
Scalp psoriasis, nail psoriasis and the rarer pustular form are forms that do not occur more often in children than in adults.
Treatment of psoriasis in children
The treatment is comparable to that of adults. For a number of the heavier treatments, however, less research is available on long-term safety, so doctors will in many cases start treatment more cautiously than is usual in adults.
Corticosteroid ointment
Corticosteroid ointment is often very effective. Especially when the affected skin area is limited, it is a good and reliable treatment with relatively few side effects. Because psoriasis patches in children often produce less thick scaling, a class 3 corticosteroid ointment (such as mometasone) is already strong enough to achieve a good result. The doctor will usually prescribe an application schedule in which the frequency is gradually reduced, sometimes with an alternating schedule (applying for a few days, then not for a few days).
Vitamin D3 analogue ointment (calcitriol, calcipotriol)
These medicines suppress the inflammation of psoriasis and also normalise the too-rapid division of the horn cells. They are often prescribed in combination with a topical corticosteroid. Because vitamin D3 analogues can affect the body’s calcium balance if absorbed through the skin, the amount that may be used is limited according to age.
Topical calcineurin inhibitors
Tacrolimus and pimecrolimus are anti-inflammatory ointments that contain no corticosteroids. They are registered for eczema, but research has shown they can also work well for psoriasis in children, and dermatologists sometimes prescribe them for psoriasis — especially on the face, where corticosteroid ointment carries more risk of side effects. In that case the medicine is prescribed “off-label” (for a different indication than the registered one).
Tar ointment
Tar ointment can also help suppress the patches. It is used less often than in the past; the drawback is the fairly strong tar smell, which many children (and parents) find unpleasant.
UVB light therapy
Light therapy is widely used in adults with extensive psoriasis that responds insufficiently. The main possible side effect is an increased long-term risk of skin cancer. There is less experience with light therapy in children, and because strong UV exposure in childhood probably carries a greater risk of skin cancer later than exposure in adulthood, the dermatologist will be more cautious about using it in children.
Systemic treatment
For severe or widespread psoriasis that does not respond to topical treatment, systemic medicines (taken by mouth or by injection), including modern biologic drugs, may be considered under the care of a specialist, with careful monitoring.
When to see a doctor
See your GP or a dermatologist if a child develops persistent red, scaly patches, a sudden crop of small spots after a throat infection, or psoriasis that is widespread, on the face, or not improving with simple treatment. Assessment confirms the diagnosis and allows a treatment plan suited to the child’s age.