Papular Urticaria
Introduction
Papular urticaria (uh-tuh-keuh-ree-uh) also known as “insect bite hypersensitivity” is an allergic reaction of the skin to bites from insects which is more commonly seen in children. It can be caused by any biting insect but more commonly seen with bed bugs, mosquitoes, fleas and midges. These bites can cause red, itchy, swollen and even blistering bumps on the skin that can last from days to weeks and occasionally months. A single bite on one part of the body can sometimes cause many spots to come up all over the body.
Although it contains the name “urticaria”, it is different to another skin condition called “urticaria” (see fact sheet on urticaria).
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Child with papular urticaria or insect bite reaction with red spotty rash on arm
Who gets it?
Anyone can get papular urticaria, but we mostly see it in children up to 10 years of age. Up to 7 in 10 children who get papular urticaria have had, or currently have, atopic dermatitis or eczema (see fact sheet on atopic dermatitis), hay fever or asthma (airway sensitivity).
Papular uritcaria is more common in warmer months such as spring and summer due to more insect activity.
Interestingly, in most cases, only one child in the family may react with papular urticaria whilst the remainder of the family have no symptoms even if they were all bitten by the same insect. This can make it difficult for parents to pinpoint the culprit.
It is usual for children with papular urticaria to outgrow it and develop tolerance, so that even if they are bitten again, they do not develop a rash.
What causes it?
An allergic reaction of the body to an insect bite is thought to be the cause. However, some children with more long-term symptoms called “chronic papular urticaria” may have no apparent cause.
What does it look and feel like?
Looks like…
Usually red bumps appear on the skin that can be small dots to large bumps. Some may even blister in the middle.
They can be found anywhere on the body but characteristically in exposed areas uncovered by clothing such as hands, feet, arms, legs and face.
They usually in clusters on the skin.
It can take a few weeks to heal and it can leave the skin looking slightly darker after it has healed or if it has been excessively scratched.
If these bumps have been scratched, they may crust over, bleed and possibly scar.
Rarely, skin infection, with a spreading red patch that goes beyond the bite, can occur (cellulitis).
Feels like…
These bumps can be very itchy.
They are usually raised.
The child is usually well.
What tests might be needed?
Generally, no tests are needed for urticaria. Your family doctor or dermatologist will ask you some questions about your child and family, and perform a skin exam where they take a closer look at and feel the skin. If needed, your doctor may recommend that a sample of the skin is taken (called a “biopsy”) to be examined under a microscope.
What treatments are available?
What can I do?
Prevent your child from getting bitten by insects:
● Dress them in clothing that covers the skin (long sleeve shirts and pants, socks and covered shoes).
● Use insect repellents on any exposed skin (especially when outdoors or in new environments).
● Check any pets for ticks or fleas and treat them and their environment appropriately.
● Use antiseptic creams to help reduce any chance of infection of the skin.
To help with the itch:
● Use thick greasy moisturisers following baths.
● Make sure your child’s nails are short to prevent them from scratching the itchy spots.
● To help with the darkened skin, protect the affected area with good sun protection practices (see Sun Protection fact sheet)
Medical therapies
Your family doctor or dermatologist may recommend creams or tablets to help with the swelling and itching. Follow your doctor’s instructions when using these medications.
● Creams: Steroid creams are usually helpful in reducing itching and swelling that your child is experiencing.
● Tablets/ syrups : There are a number of non-prescription and prescription medications that your doctor may recommend. Antihistamines and steroid medications may help reduce the symptoms and prevent more bumps from occurring. Antibiotics may be recommended especially if your doctor suspects some of the bumps may be infected.
What happens after treatment?
Papular urticaria usually goes away with time without much treatment. Your child may develop tolerance to the insect bites over a period of several years. In the meantime try to prevent your child from getting bitten. Some children may get papular urticaria again after several years.
What support is available?
If you have any concerns or any questions, please see your family doctor or local pharmacist. They will be able to refer you on to the right services for your child.
Authors/Reviewers:
Author: Dr Kevin Lam
Paediatric Reviewer: Dr Mayuri Sivagnanam
Editor in Chief: Dr Tevi Wain
