Allergische Atemwegserkrankungen im Bäckereihandwerk

Arthropod allergens and human health

Many species of arthropods are the sources of potent allergens that sensitize and induce IgE-mediated allergic reactions in humans. Most of these arthropod allergens are proteins, and the allergic response mechanism to these allergens is the same as it is for allergens from other sources such as plant pollens, molds, and foods. Aside from ingestion of crustaceans (shrimp, lobster), among arthropods, humans have the greatest contact with insects and mites, and as a result allergies to these two groups of arthropods have been the most frequently reported. Because of the large number of people affected by allergic reactions to stinging insects, cockroaches, and dust mites, many allergens of these organisms have been extensively studied, purified, and immunobiochemically characterized and for some recombinant allergens, produced. Cocktails of these recombinant allergens have the potential for use in diagnosis and immunotherapy. In this chapter, we review the insects and mites that induce allergic reactions. Where the information exists, the immunobiochemical characterization of the allergens and the frequency of sensitivity or clinical reactivity in the human population are also reviewed. As background, the beginning of this review includes sections that define allergens, explain the allergic reaction mechanism, and describe the methods for naming allergens.

Occupational IgE-mediated allergy to Tribolium confusum (confused flour beetle)

BACKGROUND

We report on IgE-mediated allergy in a worker caused by Tribolium confusum (confused flour beetle). These beetles lived in the "old" flour to which he was exposed in his work.

CASE REPORT

A 35-year-old, nonatopic mechanic in a rye crispbread factory developed rhinitis, conjunctivitis, and asthmatic symptoms, as well as urticaria on his wrists, lower arms, hands, neck, and face, during the maintenance and repair of machines contaminated by flour. This flour had been in and on the machines for a long time, and it contained small beetles. The patient did not suffer any symptoms when handling fresh, clean flour.

RESULTS

Skin prick tests with standard environmental allergens, storage mites, enzymes, flours, and molds were negative. A prick test with flour from the machines gave a 10-mm reaction. An open application of the same flour caused urticarial whealing on the exposed skin. Prick tests with fresh flour from the factory were negative. A prick test with minced T. confusum from the flour in the machines gave a 7-mm reaction. Histamine hydrochloride 10 mg/ml gave a 7-mm reaction. Specific serum IgE antibodies to T. confusum were elevated at 17.2 kU/l. Prick tests with the flour from the machines were negative in five control patients.

CONCLUSIONS

The patient had occupational contact urticaria, rhinitis, conjunctivitis, and asthmatic symptoms from exposure to flour. His symptoms were caused by immediate allergy to the beetle T. confusum. Immediate allergy to this beetle has rarely been reported in connection with respiratory symptoms, but it may be more common. Contact urticaria from this source has not been reported before.