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Background: Cross-reactivity between hymenoptera species varies according to the different allergenic components of the venom. The true source of sensitization must therefore be established to ensure the efficacy of venom immunotherapy., Objective: In the Mediterranean region, Polistes dominulus and Vespula spp. are clinically relevant cohabitating wasps. A panel of major vespid venom allergens was used to investigate whether serum-specific IgE (sIgE) could be used to distinguish sensitization to either vespid., Methods: Fifty-nine individuals with allergic reactions to vespid stings and positive ImmunoCAP and/or intradermal tests to vespid venoms were studied. sIgE against recombinant and natural venom components from each wasp species was determined using the ADVIA Centaur(®) system., Results: sIgE against recombinant antigen 5s sensitization to be detected in 52% of the patients tested (13/25). The sensitivity increased to 80% (20/25), when using natural antigen 5s, and to 100% with the complete panel of purified natural components, because the sIgE was positive to either the antigen 5s (Pol d 5/Ves v 5) or to the phospholipases (Pol d 1/Ves v 1) of the two vespids, or to both components at the same time. In 69% of cases, it was possible to define the most probable sensitizing insect, and in the rest, possible double sensitization could not be excluded. Vespula hyaluronidase was shown to have no additional value as regards the specificity of the assay., Conclusions: The major allergens of P. dominulus' and Vespula vulgaris' venom, namely phoshpholipases and antigen 5s, are required to discriminate the probable sensitizing species in vespid-allergic patients., (© 2012 John Wiley & Sons A/S.)

The most important causative factor for anaphylaxis in mastocytosis are insect stings. The purpose of this review is to analyse the available data concerning prevalence, diagnosis, safety and effectiveness of venom immunotherapy (VIT) in mastocytosis patients. If data were unclear, authors were contacted personally for further information. Quality of evidence (A: high, B: moderate, C: low and D: very low) and strength of recommendation (strong 1 and weak 2) concerning VIT in mastocytosis patients are assessed according to the Grading of Recommendations Assessment, Development and Evaluation and are marked in square brackets. Results of VIT were described in 117 patients to date. The mean rate of side-effects during treatment in studies published so far is 23.9% (7.6% requiring adrenaline) with an overall protection rate of 72%. Based on the review we conclude that (1) mastocytosis patients have a high risk of severe sting reactions in particular to yellow jacket, (2) VIT could be suggested [2] in mastocytosis, (3) probably should be done life long [2], (4) VIT in mastocytosis is accompanied by a higher frequency of side-effects, so (5) special precautions should be taken into account notably during the built up phase of the therapy [2], (6) VIT is able to reduce systemic reactions, but to a lesser extent compared to the general insect venom allergic population [2], so (7) patients should be warned that the efficacy of VIT might be less than optimal and they should continue carrying two adrenaline auto injectors [2].

Sera from a group of 12 patients with anaphylactic reactions to vespids were studied. Field observations and RAST values suggested that the offending insect was Polistes dominulus (PD). Specific IgE antibodies to PD appeared in all cases and to Vespula germanica (VG) in nine. Absorption studies in these basal sera showed that IgE antibodies to VG were due to cross-reactivity with PD. The RAST value to both venoms was higher after immunotherapy (IT) in six cases. IgE antibodies increased to determinants common to both vespids, and in 41% of the cases to specific epitopes of VG venom allergens not initially detected in the basal sera. In one case antibodies increased only to VG without a corresponding rise to PD. These results indicate that if the correct venom to which the individuals are sensitized is not administered IgE antibodies may appear which were not initially detected in the patients' sera. The levels of these antibodies declined during the course of IT.

The study was undertaken to investigate the presence of IgE antibodies to Polistes dominulus (PD), Vespula germanica (VG) and Vespa crabro (VC) in a large group of sera belonging to patients sensitized to Vespids in Spain. RAST values showed that although the majority of patients had IgE antibodies to PD, VG and VC, there was a marked predominance of PD. These results were related to the distribution of the insect in the areas where the sera were obtained. Due to geographical and insect distribution differences, the whole area was divided into three zones: Central, East and South. Comparison of the positive RAST values obtained indicated that, although the positivity to PD predominated over VG and this over VC, there were significant differences in percentage positivities to each vespid in the different regions studied. The results of the RAST absorption studies indicated that in most instances patients were originally sensitized to one vespid and were RAST positive to the other venoms due to cross-reactivity. Only in a minority of cases were coexisting antibodies to two insects present. These results show that PD and VG are the important vespids followed to a lesser extent by VC. This study provides relevant information concerning insect distribution sensitivity in a European country.

Crossed immunoelectrophoresis (CIE) pattern of Yellow jacket vespid venom showing 25 immunoprecipitates was used in crossed radioimmunoelectrophoresis (CRIE) analysis with sera from 35 subjects allergic to vespid venom. Phospholipase A and B, hyaluronidase, acid and alkaline phosphatases and a lytic active component were demonstrated in immunoprecipitates using zymography and direct haemolysis of sheep erythrocytes. CRIE analysis proved the allergenicity of these proteins. In addition, another antigen (Ag 17) with no detectable enzymatic or lytic activity was identified as an important allergen. This allergen is most likely identical to the previously described Antigen 5 in vespid venoms. By using CIE/CRIE the presence and complexity of multiple forms of the allergenic protein components were well demonstrated.

During a 21-year period in Denmark a total of 26 deaths were caused by wasp or bee stings (according to the National Health Service). The deaths might be classified, with some overlapping, as caused by either anaphylactic/anaphylactoid shocks (between 65% and 80%), suffocation after stings in the airways (about 15%) or preexisting diseases, especially arteriosclerotic heart disease (approx. 20%). Characteristically, in most persons with shock reactions unconsciousness and death occurred very shortly after the sting (within 45 min), while the interval between sting and death was longer (30 min to a couple of hours) when death was caused by suffocation. In more than 21 of the 26 cases it seemed reasonable to assume that insect allergy might have contributed to the fatal outcome. Six of these cases had a previous history of abnormal reactions to insect venom, thus only a small group would have benefited from the prophylactic effect of hyposensitisation. There was no known previous history of reactions to insect stings in the other cases, but it is likely that more than six persons had had severe reactions to insect stings on other occasions. Presumably many deaths where insect stings have been involved--through not verified as causal--are classified as inexplicable or accidental, thus the real number of deaths caused by wasp or bee stings could be substantially greater. Consequently hyposensitisation after severe insect sting reactions of verified allergic genesis can still be advised.

One hundred and seventeen persons all stung by yellow jacket (YJ) and/or bee were examined by means of skin prick test with venom of these insects, skin prick test with 10 inhalant allergens and analyses of total IgE, specific IgE and IgG against honey bee and YJ venom. Eighty-seven persons had had a systemic reaction to YJ or bee sting, the rest had reacted normally or with a large local reaction. Positive correlations (P less than 0.05) were found between results of skin prick tests and specific IgE against venoms and, for YJ, between the severity of symptoms after sting and the size prick test with the venom. That some of the more severe symptoms could have been caused by non-immunological mechanisms could explain why a significant correlation was present only between the results of the prick test and specific IgE and not between these tests and the clinical symptoms. Specific IgE values against YJ and honey bee venom showed covariation, although no correlation could be demonstrated between the clinical symptoms after stings from these insects, or between skin prick test results using the two different extracts. The severity of the sting reactions was not correlated to age, atopic disposition, amount of total IgE, number of stings during life, or positive skin prick test to inhalant allergens. It is concluded that in insect allergy, specific IgE analysis and skin prick tests are supplementary.

Clinical hypersensitivity to wasp stings was found to be fairly well correlated with the presence of serum IgE-antibodies against yellow jacket venom as detected by the RAST technique. Such antibodies were never found in a control group of non-allergic blood donors, but they were detected in a surprisingly large proportion of patients with bee sting allergy without known allergic reactions to wasps. Studies using RAST inhibition technique failed to prove cross-reactions between bee and wasp venoms. Considerably better results were obtained when venom antigens instead of whole body antigens were used in the RAST. RAST inhibition studies suggested that IgE-antibodies detected with RAST using whole body antigen are directed against bee venom constituents in the whole body extract.