Contact urticaria is a different type of allergy where the reaction starts immediately following or shortly after contact with the allergen, usually within 10-30 minutes following skin contact. It is often referred to as a Type 1 hypersensitivity. It normally settles down within an hour after contact with the causative allergen has stopped.
Common causes are:
- Natural rubber latex
- Hairdressing bleach (ammonium persulfate)
- Some foods such as seafood, meat, chicken, flour and some fruit and vegetables.
Healthcare workers are one of the occupational groups most commonly affected by latex allergy due to use of latex gloves. Latex gloves are one of the more common causes of latex allergy. Using disposable latex gloves that are powdered also increases the risk for latex allergy. The powder facilitates the transfer of the latex allergen to the skin and also aerosolises it, so latex proteins that have attached to the powder can be inhaled, or enter the skin via cracks and splits in the skin.
Some people with latex allergy can also be allergic to some fruits which have similar proteins to latex, including banana, avocado, kiwi fruit and melon.
Signs and symptoms of latex allergy:
- An itchy, red rash within minutes of contacting latex
- Hives or welts on the skin
- Itchy, red skin and/or eyes
- Runny nose, sneezing and sometimes asthma
- Burning, stinging, itching, tingling and swelling from latex contact on ‘mucous membranes’ lining internal surfaces, like the mouth (from blowing up balloons or gloves worn by dentists), or the genitals (from condoms)
The symptoms normally resolve within an hour or two after contact has ceased.
Tests used to diagnose contact urticaria include blood tests and a different form of allergy testing, called Prick testing. Prick testing is commonly used by allergists to diagnose causes of asthma, hay fever and food allergies. Blood serum tests (formerly Radio-Allergo-Sorbent Test or RAST tests) can also be used to diagnose latex allergy, and may be the safest option if a severe latex allergy is suspected.
When testing for latex allergy, it is important that the nurse performing this blood test does not wear latex gloves.
Patch testing is not used to diagnose latex allergy.
In addition to latex gloves causing latex allergy, there are many other medical and household products that may contain latex. These may include:
|Rubber bands||Some computer mouse pads|
|Balloons||Panty house or elastic in underwear|
|Goggles||Rubber electrical cords on appliances|
|Rubber innersoles||Rubber boots or rain coats|
|Some medical products such as airway masks, catheters and dressings||Items with rubber handles such as tooth brushes, golf clubs, tennis racquets|
Risk factors for latex allergy
There are some factors that may increase a person’s potential for developing latex allergy, which may include:
- A history of asthma, eczema or hay fever (called atopy)
- Damaged skin i.e. dry and cracked skin when wearing latex gloves
- Working in the healthcare industry and frequent wearing of latex gloves
- Use of powdered latex gloves. Powder facilitates the transfer of the latex allergen to the skin.
- Long term exposure to latex, especially individuals who have undergone multiple surgical operations.
Management of latex allergy:
Unfortunately there is no cure for latex allergy, so it is important to avoid contact with latex products at work and home. People who have been diagnosed with latex allergy should avoid contact with all latex products including latex gloves, balloons and condoms.
It is also important that those people inform their GP, dentist and other healthcare providers about their allergy.
Patients should be encouraged to contact manufacturers if they are uncertain if products, they are using contain latex or not.
People with latex allergy may need to wear a Medic Alert bracelet, as many healthcare facilities use latex products, and you may not be able to tell them that you are allergic to latex, particularly in an emergency medical situation.
Fortunately very few people have a severe reaction to latex, which is called anaphylaxis. Anaphylaxis causes swelling, difficulty breathing, collapse and occasionally even death. An ‘EpiPen®’ which is a special injectable adrenaline syringe, is used in an emergency to treat anaphylaxis.
For more information on anaphylaxis visit the Australasian Society of Clinical Immunology and Allergy website www.allergy.org.au
|Special note: Remember – Healthcare workers that are allergic to latex need to find an alternative suitable glove. These may include nitrile and neoprene. Vinyl gloves are not suitable as they do not adequately protect against bodily fluids.|