Latex Allergy

Natural rubber latex is used extensively in the modern world, but perhaps nowhere more so than in the healthcare environment. Allergy occurs to the plant proteins from the rubber tree, Hevea brasiliensis, which are residual contaminants of finished latex products such as medical gloves. Latex allergy emerged as a serious issue in the 1980s triggered by the advent of the AIDS epidemic and the widespread use of universal precautions. Powdered latex gloves are particularly potent sensitizers, through the combination of cornstarch donning powder with highly charged latex allergens and their propagation as allergenic aerosols within the healthcare environment. This, together with the rise in atopy in recent years, produced an epidemic of latex allergy among healthcare workers with resultant contact urticaria, occupational asthma, and anaphylaxis. Other groups of patients were also identified as having an increased risk of latex allergy, including spina bifida patients and patients who have undergone multiple surgical procedures. Important clinical subsets of latex-allergic patients are those with the latex-fruit syndrome, whereby latex allergy subjects report allergy to certain fruits, commonly banana, avocado, and kiwi fruit. These reactions are due to cross-reactive allergens in latex that share significant homology with proteins in certain tropical fruits and vegetables. Thirteen latex allergens have been identified to date and of these the most important for healthcare workers are Hev b 5 and Hev b 6, and for spina bifida children Hev b 1 and Hev b 3. The diagnosis of latex allergy rests on obtaining a history of appropriate clinical symptoms within minutes of exposure to latex proteins together with the demonstration of specific IgE by serum immunoassay or skin-prick testing. Current immunoassays have limitations and skin-prick testing reagents are not widely available, at times hampering diagnosis. Management of affected individuals is based primarily around allergen avoidance. Latex-allergic subjects must stringently avoid personal exposure to latex and, in addition, must not work in environments where powdered latex gloves are used. With these measures, the majority of affected individuals can continue to work in their profession. Recent epidemiologic studies suggest that the widespread adoption of powder-free, low-allergen gloves has resulted in a decrease in the levels of new sensitization to latex. Nevertheless, latex allergy is increasing in other populations and specific treatments are lacking. Specific immunotherapy for latex allergy has been trialed with evidence of efficacy, but is limited by systemic side effects. The search for safer immunotherapy for latex allergy is currently an area of active research.