Abstract
During the last fifteen years better hygienic standards led to an increased consumption of natural rubber latex (NRL) gloves for the protection of medical staff. At the same time case reports about an IgE-mediated allergy to NRL sometimes causing life-threatening anaphylactic reactions came up. This allergy was different from the well-known type IV reactions caused by latex additives. Health care workers and patients with multiple surgery surgeries were identified as high risk groups. For unknown reasons patients with spina bifida (SB) showed the highest prevalence of NRL-specific IgE-antibodies. A pre-existing atopy increased the risk of latex sensitization. Allergic reactions were caused mainly by medical procedures, especially surgeries, if latex gloves and other latex containing devices were used. Meanwhile some allergenic proteins in NRL (named Hev b in accordance with the rubber tree Hevea brasiliensis) could be identified. Patients in different risk groups showed distinct prevalences of sensitization to these allergens. The way of the allergen uptake (aerogen or by direct mucosal contact during surgeries) played an important role in the sensitization to different allergens. Most of the latex allergens like Hev b 1, Hev b 3, Hev b 6.02 have been totally sequenced. Since the sequence of all registrated allergens (Hev b 1 - Hev b 13) is known, it was possible to localize in Hev b 1, Hev b 5 and Hev b 6.01 several IgE binding sites as well as T cell epitopes. Cross-reacting antibodies between NRL and numerous fruit were described and for some proteins structural homologies were well characterized. For the in vitro diagnosis of NRL allergy serologic tests with improved extracts and recombinant allergens (for instance ImmunoCAPTM system) are available. NRL protein extracts for skin prick tests were difficult to standardize. The use of natural extracts in combination with recombinant latex allergens could be one possible future perspective for skin testing. The problem of NRL allergy is still not resolved but significant progress has been made in its prevention. In high risk patients like persons with spina bifida a primary prophylaxis was performed with success, but also secondary or tertiary prophylaxis allows safe operations without symptoms of NRL allergy.
Keywords: Natural rubber latex, latex allergens, latex sensitization, latex allergy, latex prophylaxis, spina bifida