BACKGROUND: The Madagascar hissing cockroach (Gromphadorhina portentosa) has become popular as a pet and as an educational tool in classrooms, zoos, and museums. OBJECTIVE: To determine whether proteins in G. portentosa are allergens and whether these allergens cross-react with those of other cockroach species. METHODS: Sera from cockroach-sensitive individuals and control subjects were used to probe immunoblots for the presence of circulating IgE that bound to proteins present in extracts of 4 cockroach species. RESULTS: Serum from an individual sensitized to G portentosa had circulating IgE that bound to proteins in extracts of all 4 cockroach species. Eight of 15 Blatella germanica-sensitized patients had IgE that bound to proteins in extracts prepared from G portentosa. Rabbit antiserum to Periplaneta americana and to Bla g 1 also contained antibody that bound to proteins in G. portentosa extract, demonstrating antigenic cross-reactivity among these cockroach species. CONCLUSIONS: Allergists, teachers, parents, and patients should be aware that sensitization and allergic reactions to the Madagascar hissing cockroach can occur. Caution should be taken if these exotic cockroaches are used in educational exercises in schools, museums, and zoos to protect predisposed individuals.
BACKGROUND: The Madagascar hissing cockroach (Gromphadorhina portentosa) has become popular as a pet and as an educational tool in classrooms, zoos, and museums. OBJECTIVE: To determine whether proteins in G. portentosa are allergens and whether these allergens cross-react with those of other cockroach species. METHODS: Sera from cockroach-sensitive individuals and control subjects were used to probe immunoblots for the presence of circulating IgE that bound to proteins present in extracts of 4 cockroach species. RESULTS: Serum from an individual sensitized to G portentosa had circulating IgE that bound to proteins in extracts of all 4 cockroach species. Eight of 15 Blatella germanica-sensitized patients had IgE that bound to proteins in extracts prepared from G portentosa. Rabbit antiserum to Periplaneta americana and to Bla g 1 also contained antibody that bound to proteins in G. portentosa extract, demonstrating antigenic cross-reactivity among these cockroach species. CONCLUSIONS: Allergists, teachers, parents, and patients should be aware that sensitization and allergic reactions to the Madagascar hissing cockroach can occur. Caution should be taken if these exotic cockroaches are used in educational exercises in schools, museums, and zoos to protect predisposed individuals.