Latex Allergy

Natural latex is the milky fluid of the Pará rubber tree, which is collected through cuts in the tree. The term ‘latex’ is derived from the Portuguese word for milk.

Latex allergy is a 20th century phenomenon. It was first described in 1927 and diagnosed for the first time in 1979 with a prick test.

Prevalence

During the HIV epidemic in the 80s and 90s, there was a significant increase in glove wearing in medical settings. An increase in the number of people with an occupational latex allergy was also observed during this time. At its highest prevalence, studies indicate that 10 to 17% of healthcare employees suffered from a latex allergy. Measures were taken to stop the spread of the allergy, which was rapidly affecting medical staff, patients and workers in the latex industry in rising numbers. These measures included:

  • Improvements in production conditions
  • Powder-free, low-allergen latex gloves
  • The use of alternative materials in glove manufacturing

    Kautschukbaum mit Auslass
    Rubber harvest

As a result of these changes, the number of allergic individuals was significantly reduced in the first decade of the 21st century. In estimating the prevalence of latex allergy, a distinction must be made between the general population and specific risk groups. For the average population without occupational exposure to latex, prevalence is between 1 and 1.37%. The figures for healthcare workers are generally higher. Depending on the region, 2.7% (Italy) or as high as 11.7% (Sri Lanka) of healthcare workers (doctors, dentists, nurses, midwives, etc.) are allergic to latex.

Risk factors for latex allergy include:

  • Employment in certain industries, for example, medical staff, rubber industry workers, cleaning service workers
  • Receiving elderly nursing care
  • Hand eczema
  • (Frequent) operations
  • Open back (spina bifida), which often requires frequent operations to correct the disease
  • Hereditary predisposition to allergies in the family
  • Allergies to certain foods (such as avocados, chestnuts, bananas, kiwis, figs, mangos and papayas)

Triggers

Natural latex is a widely available material used throughout the world. It is found not only in protective gloves but also in food (chewing gum), food packaging, self-sealing envelopes, swim caps, snorkels, diving masks, erasers, toothbrushes, coated raincoats, toys, eyelash curlers, non-slip socks, compression stockings, pacifiers, car tyres, balloons, air mattresses, preserve jar sealing rings, condoms and medical devices. Over 12 million metric tons are produced every year. So far, 15 allergens in natural latex have been identified.

The allergy is usually triggered through skin contact. However, it is also possible to become sensitised to latex via the airways. This is especially problematic in the manufacture and use of powdered medical gloves because allergens from the latex bind to the latex-free powder. If the powder is released into the air, the latex allergens can be breathed in.

In addition to medical gloves, other medical devices such as catheters can also contain latex. It is therefore very important that patients inform the medical staff about their allergy before an operation or treatment.

Many people who are allergic to latex develop cross-reactivity to certain foods or plants. In particular, tropical fruits such as avocados, bananas and kiwis have a protein structure similar to that of the rubber plant. If the immune system of a person who is allergic to certain latex proteins is exposed to these fruits – a kiwi, for example – an allergic reaction may be triggered, due to the similarity of the proteins. This is referred to as latex-fruit syndrome. People who already have an allergy to one of these foods also have a higher risk of developing a reaction to latex over time. Certain plants can also trigger cross-reactions. These include mulberry, rubber trees, poinsettia, hemp and oleander.

Symptoms

Some of the physical signs of an allergic reaction to latex are:

  • Itchy, red skin rash at the contact site (delayed or immediate)
  • Hives at the contact site (on the hands, for example)
  • Allergic rhinitis and itchy, red eyes (particularly from exposure via the airways)
  • Asthma symptoms such as coughing and difficulty breathing (particularly from exposure via the airways)
  • Anaphylactic reactions possibly leading to circulatory collapse

Diagnostic Procedure

The first step in diagnosing a latex allergy is an in-depth consultation during which the doctor asks the patient about his or her symptoms, living conditions and familial predisposition. Then a skin test (prick test or rub test) and/or a blood test are performed. These tests reveal an allergic disposition to certain substances but do not provide evidence of an actual allergy. If the results are inconclusive, a provocation test can be performed on the skin, the nasal mucosa, or another site. Any reactions are then assessed in order to determine whether latex triggers an allergic reaction or whether it can be removed from the list of suspected allergens. A comprehensive overview of the different tests can be viewed here.

Therapy

The most important method for relieving symptoms is abstention, or allergen avoidance. Gloves and condoms free from natural latex should be used, and the workplace should be thoroughly inspected for products containing latex. If latex-food cross-reactivity is a problem, certain foods must be avoided. The symptoms can also be treated with medication. Research is currently underway to investigate immunotherapy options for latex allergies.

Allergic individuals should carry an allergy passport with them at all times, to be presented at every doctor’s visit. If symptoms occur at the workplace and cannot be improved through strict allergen avoidance, it may be necessary to report an occupational illness. People at risk of a severe allergic reaction must always carry an emergency kit with them containing an adrenaline auto-injector, a corticosteroid and an antihistamine.

Legal notes

Prof. Dr. med. Dr. h.c. T. Zuberbier
Last changes made: July 2016