Individuals who are allergic to avocado, chestnuts or bananas also have an increased risk of latex allergy. Latex is a polymer of cis 1-4 isoprene and is obtained by milking the rubber tree, Hevia braziliensis, from South East Asia. Isoprene itself is not believed to be allergenic, but about 18 IgE binding proteins which are closely associated with the isoprene have been identified. These proteins range from 2.5 kilodaltons to high molecular weight proteins of 100 kilodaltons, and include rubber elongation factor, hevein and hevamine. Different patients react to different proteins in the latex sap.
Children appear to react to different proteins compared with adults.
More research is required to characterize the different latex allergens, so that reliable and appropriate testing reagents can be formulated. The abovementioned proteins are responsible for Type I allergy. Gloves may also contain other allergens, e.g. ethylene oxide, casein and corn to which patients may react with immediate hypersensitivity. These include carbamates and thiurams which are used as accelerators and hardeners. I latex allergy.