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Notes: A markedly elevated serum level of mast cell tryptase (77·6 µg/L; 95th percentile in normals 13·5 µg/L) was detected in a patient treated for 5 years with wasp venom immunotherapy because of severe anaphylaxis following a wasp sting. Retrospective analysis of stored serum samples taken during the course of immunotherapy revealed that the tryptase level had been elevated for at least 3 years. Despite several dermatological examinations, skin changes of mastocytosis had been missed. Re-examination of the patient revealed sparse macules on the thorax and thighs; Darier’s sign was negative. Histologically, mast cell accumulation in these lesions was demonstrable. No signs of systemic mastocytosis were detected. The most appropriate diagnosis was telangiectasia macularis eruptiva perstans. Even in patients with highly elevated tryptase levels, mastocytosis may go undiagnosed. As mastocytosis predisposes to severe anaphylaxis, the condition should be looked for in patients with such reactions by clinical examination and measurement of serum tryptase levels.

Notes: The first months of life may be an important period for allergic sensitization. Several studies suggest a relationship between the month of birth (MB) and the development of skin sensitivity to aeroallergens or the manifestation of an atopic disease. In 1988 and 1989 we investigated a population of 1066 Bavarian preschool children aged 5–6 years. Skin prick tests were performed with common aeroallergens (grass pollen, birch pollen, house-dust mite, eat epithelia). The personal history of atopic disease (atopic eczema, allergic rhinitis, bronchial asthma) was recorded by a questionnaire, and the presence of overt atopic disease was documented by a personal examination. Positive prick test reactions to the above-mentioned aeroallergens were found in 15.4%, 9.2%, 12.2%, and 10.4% of the subjects, respectively; lifetime prevalence of manifest atopic disease was 22.2% for atopic eczema, 11.7% for allergic rhinitis, and 4.5% for asthma. The MB distributions of children reacting to aeroallergens or of those with atopic diseases were compared with those of subjects with corresponding negative findings. Chi-square tests were performed for each aeroallergen and each of the atopic diseases separately. No significant differences among the MB distributions were found (P〉0.3). Thus, in this coherent group. MB correlated neither to allergic sensitization nor to manifest atopic disease.

Notes: In a total of 525 patients with hypersensitivity reactions to hymenoptera stings diagnostic parameters of hymenoptera venom (HV) allergy (severity of reactions, skin test threshold and RAST for bee and vespid venoms) were investigated for their relationship to the following indicators of atopy: positive history of atopic diseases, elevated (≤ 100 kU/1) total scrum IgE and positive prick test reactions to common inhalant allergens (CIA) (grass pollen, cat epithelium, house dust mite). There was a conclusive history of atopic disease in 25%, a total serum IgE ≥ 100 kU/1 in 48%, and at least one positive reaction to CIA in 53%. Total IgE ≥ 100 kU/l correlated with a higher frequency of RAST classes ≥ 2 (P 〈 0.01) and with less severe reactions to hymenoptera stings (P 〈 0.05). In the presence of at least one positive reaction to CIA, there were more frequently skin test thresholds ≤ 10 μg/ml (P 〈 0.05) and RAST classes ≥ 2 (P 〈 0.01) for HV than in CIA prick test negative individuals. There was no significant relationship between the other pairs of parameters evaluated. Thus, reactivity to HV in diagnostic tests is increased in the presence of certain indicators of atopy. This has to be considered in the interpretation of skin test and RAST results obtained with HV.

Notes: Background:  For the immunotherapy of Hymenoptera venom allergy various preparations and treatment protocols are in use. However, controlled studies making direct comparisons of the efficacy and safety of different regimens are rare.Objective:  To assess prospectively different venom immunotherapy (VIT) protocols using an aqueous or an aluminium hydroxide adsorbed allergen preparation for the treatment of honeybee venom (HBV) allergy.Methods:  Sixty-five HBV allergic patients (42 males, 23 females; aged 17–75 years) with a history of systemic anaphylactic reactions (SARs) to honeybee stings were treated according to three different regimens. During the incremental phase, patients in group A (n = 21) or B (n = 21) received an aqueous preparation according to a rush protocol. Patients in group C (n = 23) were treated with conventional (‘slow’) VIT using an aluminium hydroxide adsorbed depot preparation. The maintenance dose was 100 μg venom in all groups. Maintenance treatment in group A was performed with the aqueous preparation administered every 4 weeks, whereas in groups B and C the depot preparation was administered every 8 weeks (group B) or every 4 weeks (group C). A sting challenge test with a living honeybee was performed in 49 patients, 6–12 months after reaching the maintenance dose. Another seven patients were stung accidentally by a honeybee (‘field sting’).Results:  Treatment with the aqueous preparation evoked large local reactions more frequently than the depot preparation in the dose increase phase [53/693 (7.6%) vs 8/206 (3.9%); P = 0.059] and also in the course of maintenance therapy [85/172 (49.4%) vs 58/478 (12.1%); P 〈 0.001]. During the dose increase phase, systemic side-effects seemed to occur more frequently in patients on rush VIT with the aqueous preparation compared to patients initially treated with the conventional schedule using the depot preparation [13/42 (31.0%) vs 3/23 (13.0%); not significant). When re-stung by the culprit insect, SARs were observed in 3/20 patients (15.0%) in group A, 2/18 (11.1%) in group B and 3/18 (16.7%) in group C (not significant).Conclusions:  The aluminium hydroxide adsorbed HBV preparation caused fewer large local reactions than the aqueous preparation. The therapeutic efficacy of the three treatment protocols did not differ.

Notes: Background Disturbances of β2-adrenoceptors are discussed as a pathogenic factor in atopic diseases.Methods In this study tbe expression and function of β2-adrenoceptors on peripheral blood leucocytes (PBL) of seven atopic patients with seasonal rhinoconjunctivitis and their seven healthy controls was evaluated in relation to disease activity. Earlier reported data during pollen. season were now compared with data obtained from the same subjects after their allergic symptoms had subsided.Results The variables that had indicated a β2-adrenoceptor subsensitivity in tbe patients during pollen season returned to control values, i.e. the reduced β2-adrenoceptor affinity, the reduced β2-adrenoceptor sensitivity, the reduced increase of intracellular cyclic adenosine monophosphate (cAMP) content upon stimulation with isoproterenol, and the reduced cAMP plasma concentration (values no longer significantly different from those of controls). However, the variable that had suggested an increase in activity of the cAMP degrading enzyme phosphodiesterase (PDE), i.e. the reduced basal intracellular cAMP content of the patients, remained reduced after the pollen season (4.9 ± 1.1 pmol/lO6’cells in patients vs 8.2 ± 0.9pmol/106 cells in controls: P 〈 0.05). There were no significant differences in β2-adrenoceptor density between patients and controls at both investigations.Conclusions Atopic seasonal rhinoconjunctivitis is associated with various alterations in the PBL β2-adrenoceptor/cAMP system that depend on disease activity. The reversible β2-adrenoceptor subsensitivity is likely to be a consequence of the disease, whereas the irreversibly decreased basal intracellular cAMP content, suggested an elevated PDE activity, might be a basic trait of atopy.

Notes: Background: Hyposensitization with bee venom leads to full protection in most, but not all patients with IgE-mediated systemic reactions to bee stings.Objective: To determine the relationship of clinical reactivity to the release of mediators and to changes of antibody concentrations in the peripheral circulation at a bee sting challenge test.Methods: Blood was sampled before (0 min) and at 15, 60 and 180 min after a sting challenge from 19 patients on hyposensitization. Of these, six still reacted and 13 were protected. Histamine, mast cell tryptase, bee venom-specific IgE and IgG in the serum, and histamine release from peripheral blood leucocytes (PBL) upon exposure to bee venom were determined.Results: Tryptase above the detection level was found only at 15 (60)min in 4/6 (1/6) patients who reacted. After the sting challenge there was a significant increase of the histamine levels in patients who reacted at 15 min (P 〈 0.05) and in patients who did react at 60 and 180 min (P 〈 0.01). The total histamine content of PBL was significantly decreased after 15 and 60 min in patients who reacted (P 〈 0.01) and in those that did not (P 〈 0.05). Bee venom-induced histamine release was significantly reduced in patients reacting and those that did not at 15 min (P / 0.05), and was significantly decreased in reactors also at 60 and 180 min (P 〈 0.05/0.01). Specific IgG antibodies showed a minor decrease (P 〈 0.05) after the sting challenge in both groups, whereas specific IgE did not change significantly.Conclusion: These results indicate that bee venom anaphylaxis is associated with the release of mediators from both mast cells as well as basophils. Successful hyposensitization does not induce a state of immunological non-reactivity, but rather alters the magnitude and the pattern of mediator release.

Notes: Allergic reactions to Hymenoptera stings are frequently observed all over Europe. Rarely they may induce long-standing morbidity or even be fatal. Several investigations have shown that the emergency treatment given to these patients is often inadequate. Cutaneous symptoms respond well to antihistamines and also to adrenaline. Adrenaline is the mainstay for outside hospital treatment of more severe reactions involving the respiratory tract (bronchial asthma, laryngeal oedema) and the cardiovascular system (anaphylactic shock). Inhaled adrenaline is especially useful in respiratory symptoms, while parenteral application of adrenaline is prefered for shock treatment. All patients with severe respiratory or cardiovascular reactions must be hospitalized, treated under intensive care conditions and observed for at least 24 hr. Emergency medications including adrenaline for inhalation or for self-injection must be given to all patients with a history of systemic allergic reactions to hymenoptera stings. These patients must also get instructions for safety measures to avoid further stings. They should be referred to an allergist in order to evaluate the indication for venom immunotherapy.