For some reason this particular sap causes many allergy problems. Allergy to natural rubber latex is becoming more common.  Healthcare workers are especially prone to the condition, and it is in these people, and in children who undergo repeated surgical procedures, that the increase is occurring.

This increase is thought to be caused by the general requirement for healthcare workers to use latex gloves when patients are undergoing many treatment procedures because of the increasing prevalence of blood-borne viral diseases such as hepatitis and AIDS.  Latex gloves are prevent contact with other peoples body fluids.  

The increase in demand for latex gloves has caused a change in the methods of manufacture and many gloves now contain more natural latex protein than before.  Most adults who have become latex sensitive are either health-care workers (particularly nurses), or they are the partners of health care workers, and therefore regularly exposed to latex particles from surgical rubber gloves.  It has been suggested that some babies may become sensitised from the latex gloves used by the midwife at the time of their birth.

There are two types of allergy to rubber gloves.  One is an example of immediate allergy and the other is an example of delayed contact allergy, a cause of dermatitis. Immediate allergy can cause anaphylaxis and the allergy is caused by a latex protein. Delayed contact allergy causes a dermatitis and the chemicals used in glove manufacturer are involved as well as the latex itself.

Immediate type

Immediate type ('type I') rubber latex allergy can cause very severe reactions. Although very rare, death has been reported as a consequence of latex allergy. Those affected by true allergy to rubber latex are sensitive to one of the natural proteins. 

Such patients are usually aware that certain items cause symptoms, but there are likely to be many others items that might cause them symptoms that they have not identified.

For example, those with respiratory  (rhinitis and asthma) conditions who are allergic to rubber latex may be quite unsure which items are affecting them.  It is possible, although it has not been fully studied, that the dust that is produced by rubber tyres on our roads may contribute to both rhinitis and asthma.  Latex is widely used in household goods, personal items, sports equipment, clothing, medical devices etc.   A list of common latex-containing items is provided.

Sufferers may experience one, two or more of the following symptoms:

A significant number of healthcare workers (and in some cases their partners) is now allergic to latex.  This is thought to have happened because of the increased exposure to surgical rubber gloves used in day-to-day patient care.  The problem seems to be commonest in nurses.  This may be because a cheaper process is used for the gloves used in day-to-day patient care than when gloves are made for surgeons.

Medical latex gloves used to be powdered with starch to enable the user to put them on more easily.  However it is now claimed that non-powdered latex gloves are less allergy-causing than powdered gloves.  Whilst they may be less likely to cause wheeze or asthma, they are no less likely to cause urticaria on contact.  It seems likely that sensitivity can be caused in this was as way as by inhalation of the latex-impregnated starch particles.

Synthetic, polyethylene or vinyl, powdered gloves are now available and these cause no problem.  However they do not provide the same barrier against infection.  Gloves made from neoprene do not cause allergy but protect against infection as thoroughly as natural latex.  Since they are not made from rubber trees, they contain no rubber latex.  Unfortunately, they are much more expensive.  

Because glove powder becomes airborne during the working day in the operating theatre, this may contribute to the asthma problems of latex-sensitive theatre nurses.  It has been shown that an increasing concentration of latex-coated starch particles increases during the working day in operating theatres when powdered gloves are used.  This powder can evidently not only cause latex-allergic people to get symptoms, it may also cause the latex allergy in the first place.

Delayed type - dermatitis

Rubber glove allergy causes a skin rash on the hands and wrists and it is a quite different condition from immediate type rubber latex allergy. Contact eczema or dermatitis due to 'type IV' allergy is the cause and the chemicals used when processing the rubber may be as much to blame as the rubber latex itself. It is just as commonly associated with household rubber gloves as with the rubber latex gloves used in hospitals.

Latex food syndrome

Proteins very similar to the allergy-causing proteins present in latex (a plant sap) are present in other plants, and some of these are foods.  For example, a latex-allergic person may have a reaction if they eat a banana; this is then known as a cross-reaction. It is caused when there is a very close structural similarity between the two similar proteins due to the sequence of their amino acid building blocks.   

Although symptoms are normally fairly mild, in theory (and very occasionally in practice) these foods can cause anaphylaxis in a latex allergic person.  Other foods that have been found capable of causing these cross-reactions in latex-sensitive people are shown below. The resulting condition is known as latex fruit syndrome and a very similar condition is called the pollen fruit syndrome in which the cross-reaction is between the food (certain fresh fruits and raw vegetables) and the pollen. Collectively these conditions form the oral allergy syndrome, as mouth symptoms are the most common manifestations of the problem. 

Foods that have ever caused symptoms should be avoided. If any of the foods listed below (the commonest are shown in bold type) are known not to cause symptoms, they need not be avoided, but sufferers need to be aware that the food could start causing symptoms at some time in the future, and avoid it once this is suspected.

Everyday items that may contain rubber latex

Many everyday items contain rubber latex.  Likely categories include household goods, personal items, sports equipment, clothing, and medical or dental devices. The severity of symptoms will differ widely from person to person according to the degree of sensitivity and the responsible allergen. Patients need to be aware of the wide range of potential culprits, although the vast majority of sufferers, will not need (neither will most be able) to avoid all of them.  The following list is by no means complete, but it gives an idea of the scope of the problem:

In some cases some there may be differences in provocation of symptoms between different brands of the same item as different manufacturers may use varying manufacturing processes.  However, it is sensible to avoid latex as far as it is possible to do so to both prevent symptoms day-to-day and to avoid worsening the degree of sensitivity.  People who have ever suffered a severe reactions should not use any item they know or suspect contains rubber latex.

Latex in hospitals, clinics and dental surgeries

It is as a result of repeated visits to the operating theatre, and the repeated use of latex catheters, that most children (e.g. those suffering from spina bifida) acquire rubber latex allergy. It is as a result of exposure at work (e.g. hospital nurses, dental nurses) that most cases of latex allergy in adults are acquired. 

If you are allergic to rubber latex, it makes no difference if your symptoms are relatively minor, you are still at risk from anaphylaxis if you have an operation.

The surgeon may be using latex gloves, and these will be in contact with your tissues for prolonged intervals. Latex catheters or other products made from natural rubber latex may also be used. This means that you are likely to be in far more prolonged contact than you have been previously.  

If your job involves regular rubber latex exposure (for example, a nurse or doctor) you may fear telling anyone for fear of losing your job. Nurse often fail to report the mild rashes and itching that happens when they use surgical gloves. Proper procedures need to be followed to ensure that such employees do not place themselves unnecessarily at risk from anaphylaxis if they themselves require an operation or medical or dental procedure. The increased risk of anaphylaxis due to latex exposure at the time of an operation is due not only to the increased and more prolonged level of exposure to latex, but also to the accompanying additional stresses that apply. It is quite possible for someone who has only previously experienced mild symptoms to have a severe reaction during an operation.

Latex allergy sufferers should ensure that medical staff are aware of their allergy. It's not just latex gloves that need to be avoided; rubber latex is also used in a wide range of medical appliances and devices.  In all cases there are alternatives that can be used and most large hospitals now have latex-free operating theatres.  For further information please visit the website of the Latex Allergy Support Group.

So why are latex gloves still used if they cause so much difficulty. Alternatives carry disadvantages and are far more expensive.  Surgeons much prefer the latex variety, provided that they themselves are not latex allergic. Hospitals are clearly obliged to provide alternatives both for latex sensitive workers and patients.

Increasingly a change away from the widespread use of latex is already beginning to occur. Surgeons have always been at less risk than nurses and this has been shown to relate to the higher quality of the gloves used in operating theatres. So changes to the methods of manufacture have lead to the development of low-allergy latex. Not an ideal solution but a favourable development nonetheless.

It has also been shown that powdering (for ease of use) latex gloves increases the risk of allergy. The powder (starch) particles make the latex allergen become airborne, thus making exposure via the respiratory tract likely to occur. So now that non-powdered low-allergy natural rubber latex gloves are readily available, it is no longer acceptable to use powdered and high-allergy latex gloves in areas such as operating theatres. There is evidence that hospitals that these decisions early have not encountered the same levels of latex-allergy (and especially latex asthma) amongst the theatre staff.

 

Latex Sensitisation in the Health Care Setting  Department of Health Report

Latex in catering

An further issue relates to the use of latex in the catering industry.  Food handlers who wear latex gloves when preparing or packing foods, and those who wear latex gloves (for reasons of hygiene) when preparing sandwiches are not only themselves at risk of developing latex allergy, they will be contaminating the food with latex allergens, and this may add to the list of items that might cause problems for those allergic to latex.  As yet, this is no more than a theoretical possibility, but it would be surprising if there was no problem.  Allergic reactions (including anaphylaxis) without apparent cause, are quite common in the allergy clinic, and allergy to hidden latex as an occasional explanation is certainly a possibility. The Latex Allergy Support Group is therefore trying to persuade large supermarket chains to ban the use of latex gloves from food preparation.  It is also campaigning against the use of latex adhesives in food packing.  These are used when the more usual adhesive methods would cause damage to a product.  There are reports of people reacting to these latex adhesives. 

In August 2006, research consultants Leatherhead Food International reported to the Food Standards agency that an examination of food packaging and adhesive labels showed that latex was present amounts sufficient to induce allergy in the most sensitive in about one third. The latex is used either as a cold adhesive seal in the case of a wrapper or the adhesive in a self adhesive label. However, there is no law that requires food producers to indicate the presence of latex on the wrapper. 

Recommended Organisations

The Anaphylaxis Campaign
2 Clockhouse Road
Farnborough
Hampshire
GU14 7QY
u www.anaphylaxis.org.uk

Latex Aware - UK Latex Allergy Support Group
PO Box 36
Cheltenham
GL52 4WY
u www.lasg.co.uk