M. Götz

Identification by immunoblot of venom glycoproteins displaying immunoglobulin E-binding N-glycans as cross-reactive allergens in honeybee and yellow jacket venom.

Background IgE antibodies against carbohydrate epitopes have been identified recently as a major cause of in vitro double positivity to honeybee (HB) and vespid venom in patients with stinging‐insect allergy. As these antibodies possibly have low clinical relevance they may be misleading in the diagnosis of venom allergy.

Cross-reactivity between Ficus benjamina latex and fig fruit in patients with clinical fig allergy.

Backgroundu2003 Anaphylactic reactions to fig fruits (Ficus carica) have been reported from subjects sensitized to Ficus benjamina (FB) latex allergens. Figs may also be involved in the latex–fruit syndrome.

Oilseed rape pollen is a potentially relevant allergen

Oilseed rape (Brassica napus) (OSR) is a partly wind‐pollinaled crop which has been increasingly cultivated both in Europe and overseas. Allergological data about OSR is scarce and controversial. We evaluated the frequency of sensitizalion to OSR pollen by skin prick test and RAST over a period of 1 yr. Airborne OSR pollen load and the agricullural role of this crop were analysed. Furthermore, six patients were investigated by immunoblot. In 4468 patients with suspect inhalant allergy investigated between June 1994 and May 1995, routine skin prick testing revealed OSR sensitivity in 7.1% ot pollen‐allergic patients. In all, monovalent sensitization was detected in nine patients. Routine pollen counts showed daily maxima not exceeding 50 grains/m3/24 h, but airborne OSR pollen has continuously increased during the last decade correlating with the increasing acreage. Characterization of OSR allergens by immunoblol revealed major allergens of 6/8 kD, 12/14 kD and in the high molecular weight range at 33, 42, 51, 58/61 and 70kD. Some OSR proteins may cross‐react with birch pollen allergens. In summary, the results suggest that OSR pollen is a moderate but true source of allergy and may sensitize despite low pollen exposure.

Sensitization to Ficus benjamina: relationship to natural rubber latex allergy and identification of foods implicated in the Ficus‐fruit syndrome

Background Ornamental Ficus benjamina (FB) has been recognized as a new indoor allergen. Little is known about the prevalence in moderately exposed subjects and the proposed association with fruit and Hevea latex hypersensitivity.

Identification of Oilseed Rape (Brassica napus) Pollen Profilin as a Cross-Reactive Allergen

Background: Major allergens of oilseed rape (OSR) pollen with molecular weights of 6/8, 14 and between 27 and 69 kD have been described. The aim of the present study was to further characterize the 14-kD allergen. Methods: The 14-kD protein was purified from OSR pollen extracts by poly-(L-proline) (PLP)-Sepharose affinity chromatography and characterized immunologically by means of allergic patients’ IgE antibodies, profilin-specific rabbit antisera, Western blot and ELISA inhibition using recombinant birch profilin (rBet v 2), and skin prick testing. Results: By PLP affinity chromatography, OSR pollen profilin was purified as a single protein of 14.5 kD and further identified as a profilin by three polyclonal rabbit antisera raised against ragweed and tobacco pollen profilin and the C-terminus of birch profilin. IgE binding of a human serum pool (n = 15) and four profilin-reactive sera to nitrocellulose-blotted OSR profilin was completely inhibited by 1 µg/ml rBet v 2 (birch profilin). Reciprocal ELISA inhibition using increasing concentrations of rBet v 2 and purified OSR profilin, respectively, showed that rBet v 2 strongly inhibits antibody binding to OSR profilin, whereas almost 100 times the amount of OSR profilin was needed to inhibit IgE binding to rBet v 2. Skin prick tests were positive (wheal ≧3 mm) with 5 µg/ml rBet v 2 in all three patients tested, and with OSR profilin in two patients at a concentration of 50 µg/ml. Conclusions: OSR pollen profilin shares IgE and IgG epitopes with Bet v 2 and other plant profilins and may represent a potentially relevant allergen for profilin-sensitized patients.

Adverse reactions to alcoholic beverages: a diagnostic guideline

Boehncke and Gall describe an interesting case of Type 1 allergy to the ethanol metabolite acetic acid [1]. This case underlines that adverse reactions to alcoholic beverages, either induced by inununological mechanisms or non-immunological mechanisms, are a frequent cause for consultation of the allergologist, but still present difficulties in diagnosing. In our experience, an allergic reaction presents itself more focused on a single or few similar beverages. An intolerance reaction is more non-specifically directed against several drinks and foodstuff. If a type 1 allergy is suspected, a screening skin prick test with the suspected beverage, ethanol, methanol, acetic acid, formaldehyde and acetaldehyde, besides a food series and total IgE, should be done as described in the paper by Boehncke and Gall. The second branch of screening concerns intolerance reactions against biogenic amines such as histamine or against sulfite. A double blind placebocontrolled red wine challenge [2,3,4] may discriminate and help to find the diagnosis. For testing, red wine is used both native (placebo) and with added histamine (verum). We recommend test wines with 200/.ig and 3.700/ig histamine per litre respectively [3]. In our experience histamine intolerance, a disease characterized by reduction in or lack of diamine oxidase activity, has to be considered the most frequent intolerance reaction against alcoholic beverages, as alcohol inhibits the histamine degrading enzyme diamine oxidase [2,3,4]. Once easy to perform measuring methods for diamine oxidase become available, standard assessment of histamine and diamine oxidase will become the gold standard in the diagnosis of adverse reactions against alcoholic beverages or food.

222 Histamine in wine: Bronchoconstriction after a double blind placebo controlled red wine provocation test

A 38-year-old woman with a history of seasonal rhinoconjunctivitis reported repeated attacks of wheezing after drinking various alcoholic beverages. Two consecutive histamine provocations using two identical samples of red wine containing 200 micrograms histamine/l and 3,700 micrograms/l, respectively, were performed in a double-blind placebo-controlled fashion to assess a possible histamine-induced bronchoconstriction. Lung function, plasma histamine, skin temperature, pulse rate and symptoms were assessed. In 3 male controls, four consecutive wine tests were performed in a randomised double-blind placebo-controlled fashion. Drinking wine with 3,700 micrograms histamine/l caused coughing and wheezing with a decrease in lung function. Plasma histamine showed an increase at 10 and 20 min and decreased at 30 min both after histamine-rich as well as histamine-poor wine, reaching the peak increase after histamine-rich wine. Controls did not react and plasma histamine levels did not increase. Bronchoconstriction after wine or food rich in histamine seems to be caused by diminished histamine degradation on the basis of reduced activity of diamine oxidase. Histamine in wine may induce bronchoconstriction in patients suffering from histamine intolerance.

Disease Patterns in the Presence of Histamine Intolerance

Headache (cephalea) is a common problem, especially in women. Usually the symptoms are attributed to the weather or the cervical spine. A prerequisite for the former is a specific type of hypersensitivity, while a prerequisite for the latter would be an injury, a degenerative disease, or a muscle tension. However, the fact is that both of these phenomena are cited as causes by patients much more frequently than would be justified on the basis of the slightest evidence. One takes headache for granted. Some patients even consider it normal.