Towards a European registry of severe allergic reactions: current status of national registries and future needs.

The incidence of severe allergic reactions is largely unknown and information about triggering allergens, aggravating factors, demography of patients and medical care is lacking. A European wide registry could provide a powerful tool to improve the management of severe allergic reactions from both a medical and a public health perspective. Analysis of existing registries regarding the type and quality of data being collected was used to develop a plan for a pan-European registry, including the type of system to be used and the range of data to be entered. Surveillance will provide evidence for the efficacy of risk management measures and may identify the emergence of new allergenic foods, and aid monitoring of novel foods, ingredients and technologies. Patients need a clear indication of factors that may increase their risk of having an adverse reaction, which such a registry can help compile. Based on the collected data, food businesses will be able to develop educational programmes for allergen risk assessment and allergen risk communication. Finally, and most importantly preventive measures can be developed and government agencies receive population based data which may be relevant for legislative purposes.

Identification of fish species after cooking by SDS-PAGE and urea IEF: a collaborative study.

A collaborative study, to validate the use of SDS-PAGE and urea IEF, for the identification of fish species after cooking has been performed by nine laboratories. By following optimized standard operation procedures, 10 commercially important species (Atlantic salmon, sea trout, rainbow trout, turbot, Alaska pollock, pollack, pink salmon, Arctic char, chum salmon, and New Zealand hake) had to be identified by comparison with 22 reference samples. Some differences in the recoveries of proteins from cooked fish flesh were noted between the urea and the SDS extraction procedures used. Generally, the urea extraction procedure appears to be less efficient than the SDS extraction for protein solubilization. Except for some species belonging to the Salmonidae family (Salmo, Oncorhynchus), both of the analytical techniques tested (urea IEF, SDS-PAGE) enabled identification of the species of the samples to be established. With urea IEF, two laboratories could not differentiate Salmo salar from Salmo trutta. The same difficulties were noted for differentiation between Oncorhynchus gorbuscha and Oncorhynchus keta samples. With SDS-PAGE, three laboratories had some difficulties in identifying the S. trutta samples. However, in the contrast with the previous technique, SDS-PAGE allows the characterization of most of the Oncorhynchus species tested. Only Oncorhynchus mykiss was not clearly recognized by one laboratory. Therefore, SDS-PAGE (Excel gel homogeneous 15%) appears to be better for the identification, after cooking, of fish such as the tuna and salmon species which are characterized by neutral and basic protein bands, and urea IEF (CleanGel) is better for the gadoid species, which are characterized by acid protein bands (parvalbumins). Nevertheless, in contentious cases it is preferable to use both analytical methods.

A study on severe food reactions in Sweden--is soy protein an underestimated cause of food anaphylaxis?

BACKGROUND AND METHODS: Because of a fatal case of soy anaphylaxis occurring in Sweden in 1992, a study was started the following year in which all physicians were asked to report fatal and life-threatening reactions caused by food. The results of the first 3 years of the study are reported here, including results from another ongoing study on deaths from asthma during the same period. RESULTS: In 1993-6, 61 cases of severe reactions to food were reported, five of them fatal. Peanut, soy, and tree nuts seemed to have caused 45 of the 61 reactions, and four of them were fatal. If two cases occurring less than a year before our study started are included, we are aware of two deaths caused by peanuts and four deaths caused by soy. All four youngsters who died from soy anaphylaxis with asthma were severely allergic to peanuts but had no previously known allergy to soy. In most cases, there was a rather symptom-free period for 30-90 min between early mild symptoms and severe and rapidly deteriorating asthma. CONCLUSIONS: Soy has probably been underestimated as a cause of food anaphylaxis. Those at risk seem to be young people with asthma and peanut allergy so severe that they notice symptoms after indirect contact.

[Fatal and severe food hypersensitivity. Peanut and soya underestimated allergens]. / Letala och svåra reaktioner av livsmedel. Jordnöt och soja underskattade allergen.

Severe allergic reactions caused by foodstuffs have been reported in Sweden since 1993, 60 cases, five of them fatal, occurring during the first 3-year period. More than 70 per cent of all reactions reported were caused by patients, soya beans, nuts or almonds. In only 13 per cent of reported cases were the patients over 17 years of age. Several severe reactions were caused by soy protein, and mainly in children and adolescents with extremely severe peanut allergy and asthma. In many cases, severe symptoms first appeared more than one hour after soy intake. The report suggests soy allergy to be associated with an underestimated risk of severe reactions.

Labelling of potential allergens in food.

In order to avoid food that they cannot tolerate, consumers suffering from food allergy or intolerance need sufficient and correct, information about food products. Labelling requirements are not satisfactory in this regard. Registration of adverse reactions in Sweden show that out of 77 cases, 51 were a result of inadequate labelling, six cases were fatal and several others required hospitalization. International recommendations for the labelling of food (Codex Alimentarius, a joint WHO/FAO organization) do not require specification of ingredients in composite ingredients if the composite ingredient constitutes less than 25% of the food (25% rule). Some ingredients are declared by category names. Ingredients such as milk, eggs, nuts, peanuts, fish, cereals, etc., will not appear on the label in these cases. Amendments are being discussed with a view to providing allergic consumers with more adequate information. A lowered specification limit for declaring ingredients in composite ingredients is suggested, combined with the establishment of a list of certain specific potent allergenic ingredients that should always be specified if present. Although many measures are needed to improve the situation for the allergic consumer, appropriate labelling of each product is fundamental. Adequate labelling is an important prerequisite for secondary prevention, a necessary basis for other measures and in addition will increase knowledge, awareness and caution in food production.

Differentiation of meat from horse, donkey and their hybrids (mule/hinny) by electrophoretic separation of albumin.

Meat from the species horse, donkey and their hybrids, mule/hinny, can be reliably identified by determination of genetic variants of serum albumin by starch gel electrophoresis of meat extracts. Staining of the starch gel for carboxylesterase activity permits differentiation of most horses from donkeys while mules/hinnies cannot be distinguished from horses by their esterase activity alone.

The effect of C4 on C1 binding and activation.

Cell-bound human C4 enhances the uptake of C1 by immunoglobulin-carrying cells. The effect is more pronounced with small amounts of IgG than with large amounts. Furthermore, the presence of C4 on the cell surface dramatically promotes the enzymatic effect of C1 on C2. The C1 binding is efficiently blocked, and the C1 activation is almost abolished by pretreating IgG-bearing cells with protein A from Staphylococcus aureus. In contrast, protein A has no effect on cells carrying C4 in addition to IgG. Protein A added in small amounts to IgG-coated sheep erythrocytes inhibits the haemolysis by subsequently added human serum, whereas even larger amounts of protein A has no effect when added to cells carrying C4 as well. Cells with and without C4 take up protein A equally well.