Quiz Yourself:
Identify which symptoms are associated with each type of reaction.
Put your mouse pointer over the red button next to the corresponding symptom to reveal the correct response. If it is blank that symptom is not associated with the reaction. If a check is revealed the symptom is associated with the reaction.
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Note: If you are unable to view the answers from the above exercise, click here to display them without using Java.
How is latex allergy diagnosed?
History and physical are crucial to diagnosis. A blood test (RAST test) may be done to detect antibodies but it is often unreliable since a person with a positive history may have a negative RAST test. Often, a scratch test is done. The skin on the forearm is pricked and a solution containing latex is dropped on the area. If the area becomes red, swollen, and itchy within 15 minutes, the test is positive. However, there is no commercially available testing solution. This leads to variance in the amount of latex in the solution used by different physicians, since they make their own. A patch test is similar in that a piece of latex glove is applied to the arm for up to 15 minutes. Hives with itching or redness indicates a positive response. The physician may not even do the scratch or patch tests on a person with a strong history, as the tests themselves have caused some people to experience anaphylaxis.
What about treatment?
Researchers in Europe have conducted clinical trials on immunotherapy for latex allergy. In one study, administering oral and subcutaneous natural rubber latex allergens significantly lowered the incidence of rhinitis, conjunctivitis, and skin reactions; however, it did not significantly affect asthma associated with latex allergy (Brehler & Kutting, 2001). In another study, there were a large number of systemic reactions to the latex injection during both the initial therapy and the monthly maintenance injections (Brehler & Kutting). Since people may react to different combinations of the latex proteins, it will be difficult to find a common treatment for all latex allergy sufferers. Therefore, immunotherapy is considered an experimental treatment, and avoidance of exposure is the primary treatment and means of prevention.
There have been many advances in latex allergy research. For example, the specific proteins that are the major allergens for people with spina bifida have been isolated, and it's been discovered that they are not the same proteins that are the primary allergens in healthcare workers (Brehler & Kutting, 2001). This may be explained by a difference in the routes of exposure between the 
two groups, and different means of subsequent sensitization. The allergens that affect children with congenital malformations (such as spina bifida) are particle-bound proteins that are less soluble than other latex proteins. Sensitization to these proteins may be caused by repeated mucosal contact. Healthcare workers tend to be exposed primarily through topical and respiratory contact since they wear latex gloves for long periods of time, and constantly inhale the powder that is all around them. It's been theorized that neonates who develop latex allergy are sensitized by inhaling the powder from latex gloves worn in the delivery room. Studies done with mice show that the mice develop IgE antibodies to specific combinations of latex proteins based on the type of exposure they've had (injected vs. topical vs. inhaled). There's also evidence that latex proteins may be altered to form new allergens during glove manufacturing. One study found an allergen in a surgical glove extract that is not found in natural rubber (Brehler & Kutting). There's still a lot of research to be done, but isolating the specific allergens to each population and method of exposure gives hope that there may effective treatments developed in the future.
