Urticaria in children

Where does the name urticaria originate from?

Urticaria comes from the latin word urticaria, to burn, or hives.

How can we tell that the rash is indeed urticaria?

In addition to the non-typical appearance of this rash, one of the characteristic findings this rash has is an irritating itch that accompanies it and really affects the patient’s quality of life. An additional finding is that it has a tendency to “migrate” from one site to another, and if you follow one specific lesion or even mark it, you will find that it will not remain in that specific site for longer than a day. In addition, urticaria disappears without leaving behind scarring or any traces on the skin.

What are the different types of urticaria?

There are two types of urticaria, distinguished by the duration of time they last on the body.
Acute urticaria – this is a rash that presents acutely, and typically lasts for several days, even though the formal definition includes rashes that last for up to 6 weeks and resolve without leaving any traces.
Chronic urticaria – this rash typically lasts over 6 weeks and is visible almost every day within those 6 weeks.
Most of the cases in children will, of course, fall under the first category.

How is acute urticaria diagnosed?

A skilled pediatrician will be able to detect this rash. There is no need for any further laboratory work or other investigations for the diagnosis to be made.

What are the causes of acute urticaria?

A small number of cases are associated with food allergies or medications. Therefore, it is very important to take a good history from the parents and review any exposures to new substances or food since the onset of the rash. It is important to realize that when urticaria is the manifestation of food allergy, it presents immediately after consumption of the food (almost always within an hour), and it is less likely to be the result of a food a child had previously consumed many times. In addition, a prolonged rash, and especially one that lasts over a day, is not typically in line with a food or drug allergy. Your pediatrician will find out whether the history fits with one of these causes.

To be on the safe side, if together with the urticaria the child presents with difficulty breathing, or any other acute symptoms, seek medical attention immediately.

But, and this is an important but – in most of the situations acute urticaria in children is associated with transient viral infections. In addition, in many of the situations, we cannot find the specific viral infection at the time of the rash, and the cause of the rash will remain unknown.

Many parents are interested in the need for food allergy tests or drug allergy tests when their child presents with acute urticaria. As mentioned above, if the child has not had a clear exposure to a new food or drug with an immediate reaction, these tests are useless and could lead to unnecessary avoidance of foods, and the indirect development of food allergies.

How is acute urticaria treated?

If needed, and to help relieve the pruritus, the pediatrician may prescribe you with anti-histamines. However, most of the time, there is no need for any treatment.

Treatment with steroids is reserved for severe cases and is certainly not routine for all cases of acute urticaria. What you should also keep in mind is that in these situations it is not recommended to use NSAID drugs such as ibuprofen, as these may make the rash worse.

What is chronic urticaria?

As mentioned above, this is an urticarial rash that lasts for longer than 6 weeks. This is much less common in children as these are situations when there is an abnormal response of the immune system that causes the activation of mast cells. These cells secrete substances that cause development of rash and itchiness. Most of these cases will present without any triggers, but some will present following exposure to physical pressure on the skin, such as heavy weight, exposure to cold, sun etc. In these situations, avoiding the trigger can help improve the rash.

When a trigger is not detected, which happens in most of the cases, the rash is considered to be a spontaneous, chronic urticaria. In these situation, the urticaria may be resistant and last for several months. But the good news is that about half of the time it will resolve within one year from the start of symptoms and the majority of cases will completely resolve within 5 years.
Nonetheless, because these situations can be related to other autoimmune diseases, it is important to carry out laboratory tests at least once in order to rule out these types of diseases. Usually, these investigations turn out to be normal.
In addition, this rash is not a manifestation of an allergy to external substances, and there is no need for skin patch tests or further allergy investigations.

How is chronic urticaria treated?

The main tool that helps with chronic urticaria is treating against the cause of the symptoms – anti-histamines (see above if you have already forgotten what anti-histamines are!). Most of those who suffer from this condition will benefit from regular treatment with anti-histamines, and studies have shown that it is safe to administer them in high doses, several times a day, for extended periods of time. Avoiding steroidal treatment as much as possible is recommended.

If the first line of treatment is not helpful, we can proceed to adding additional drugs. Those who have resistant urticaria may benefit from a new, ground-breaking biologic drug based on IgE antibody that can be injected once every few weeks. This drug is now available for urticaria and can bring about good results and help control the rash.

In summary, acute urticaria is typically the result of a response to infection and is not concerning in itself (even though it can sometimes look very impressive).
In terms of investigations, it is important to rule out drug or food allergy, and this can usually be done by taking a careful medical history, and when the history does not suggest an allergy, being patient and treating the pruritis only.
Chronic urticaria on the other hand, requires long term treatment, even though the prognosis is good, and the vast majority of the cases will resolve spontaneously.
Good luck.