Arthur Helbling

Immunotherapy with honeybee venom and yellow jacket venom is different regarding efficacy and safety

Venom immunotherapy (VIT) for Hymenoptera allergy is accepted as safe and effective. However, widely varying success rates and frequencies of side effects are reported. Differences between various Hymenoptera species could account for these diverging results. We therefore analyzed 205 patients with a history of systemic allergic reactions to either honeybee (148 patients) or yellow jacket stings (57 patients) during VIT. All patients had a positive skin test to the respective venom before VIT, were monitored for side effects of VIT, and submitted to a sting challenge while they were receiving VIT. Patients with honeybee-venom allergy had a higher sensitivity in both skin tests (p less than 0.05) and RAST (p less than 0.001) than patients with yellow jacket-venom allergy. They developed systemic side effects to VIT injections significantly more often (41% versus 25%; p less than 0.01) and also reacted more frequently to the sting challenge (23% versus 9%; p less than 0.01) than patients with yellow jacket-venom allergy. We conclude that results obtained from studies on the allergy to one Hymenoptera venom cannot be extrapolated to allergies to other Hymenoptera venoms.

Honeybee venom allergy: Results of a sting challenge 1 year after stopping successful venom immunotherapy in 86 patients

In 86 patients with a history of severe systemic reactions (SRs) to honeybee stings confirmed by a positive skin test and/or RAST to honeybee venom (HBV), immunotherapy (IT) with HBV was stopped after 3 to 10 years. All patients had tolerated well a honeybee sting during IT and were resubmitted to a sting 1 year after VIT was stopped. At the latter time, 15 patients (17%) developed an SR and 71 did not. There was no difference between the two groups regarding age, sex, IT duration, severity of the SR before treatment, as well as diagnostic tests with HBV (skin tests, RAST, and specific IgG) before the challenge. Patients with a relapse of their allergy had, however, developed allergic SRs to IT injections more frequently than patients with lasting protection (p less than 0.001). SRs to the sting challenge (CH) after IT was stopped occurred more frequently in those patients in whom efficacy of IT had previously been confirmed by lacking responses to a field sting than in patients who had tolerated an intentional CH during the injection period (p less than 0.025). Indeed, the incidence of relapse after venom IT was stopped was only 9.6% in patients who had previously tolerated an intentional CH. It is concluded that well-tolerated HBV IT may be stopped after at least 3 years, provided its efficacy has been documented by a CH without SR.

Fish allergy: is cross-reactivity among fish species relevant? Double-blind placebo-controlled food challenge studies of fish allergic adults

BACKGROUNDnAllergic reactions to fish are a common cause of food allergy in many areas of the world where fish is a major source of protein. Although different species of fish may be consumed, possible cross-reactivity has received limited investigation.nnnOBJECTIVEnThe aim of this study was to assess potential cross-reactivity to different species of fish species using double-blind, placebo-controlled food challenges (DBPCFC) in fish-allergic adults and to compare skin test and RAST reactivity with the challenge response.nnnMETHODSnNine skin prick test and/or RAST-positive adult individuals with histories of an immediate-type reaction following fish ingestion were challenged with different fish species using double-blind, placebo-controlled food challenge.nnnRESULTSnOf a total of 19 double-blind, placebo-controlled fish challenges performed, 14 challenges (74%) resulted in the induction of objective signs that were consistent with an IgE-mediated response. The most common sign observed was emesis (37%); the most prevalent subjective symptoms reported were compatible with the oral allergy syndrome (84%). Three subjects reacted to at least three fish species and one subject reacted to two fish species tested. In regard to the positive challenges, predictive accuracy of skin prick test and RAST was 84% and 78%, respectively.nnnCONCLUSIONnOur results indicate that clinically relevant cross-reactivity among various species of fish may exist. Advising fish-allergic subjects to avoid all fish species should be emphasized until a species can be proven safe to eat by provocative challenge.

Immunopathogenesis of fish allergy : identification of fish-allergic adults by skin test and radioallergosorbent test

BACKGROUNDnAs the consumption of fish increases in the United States, the importance of allergic reactions to fish has become clear. Since most previous studies on fish allergy have focused on children reacting mainly to codfish, there is a need to investigate allergic reactions to other fish in adults.nnnOBJECTIVEnTo identify fish-allergic adults, and to assess cross-reactivity among different species of fish by RAST inhibition.nnnMETHODSnThirty-nine individuals who reported fish allergy were selected for study; 32 (82%) were atopic as defined by two or more positive skin tests to common inhalant allergens and a history of allergic reactions and 33 (85%) experienced allergic symptoms within 30 minutes after ingesting fish. The most frequently reported symptoms were hives (69%), itching (69%), and wheezing/chest tightness (54%). Study subjects were skin tested with fish extracts and their sera assayed for IgE antibodies to different fish species.nnnRESULTSnThirty-six (92%) of the subjects tested had a positive skin test to at least one of 17 fish extracts tested; 9/35 (26%) reacted to all 17 extracts. Of the atopic (two or more positive skin tests to common inhalant allergens plus a personal and/or family history of allergy) and nonatopic fish-tolerant controls, 20/26 (77%) reacted by skin test to one or more fish extracts tested; the most prevalent positive reaction was to anchovy (73%). A significant correlation (P < .01) was observed between skin test reactivity of fish-allergic subjects to most fish extracts and fish RAST reactions. Radioallergosorbent inhibition testing demonstrated significant cross-reactivity among pollack, salmon, trout, and tuna; and between mackerel and anchovy.nnnCONCLUSIONnThese results suggest that fish-allergic subjects may be clinically sensitive to more than one species of fish. Skin test reactivity to fish by itself is not an adequate criterion for the confirmation of clinically relevant fish allergy; consequently, fish-allergic subjects with positive skin tests to several fish species should exercise caution when eating fish until tolerance can be demonstrated by double-blind, placebo-controlled food challenge, at the patients earliest convenience.

Comparison of Psilocybe cubensis spore and mycelium allergens

BACKGROUNDnBasidiospores are an important cause of respiratory allergy in mold-sensitive atopic subjects. Collection of the large amounts of spores required for extract preparation is tedious and difficult. A desirable alternative could be mycelium grown in vitro if it is allergenically similar to spores.nnnMETHODSnTherefore this study compared the allergen contents of Psilocybe cubensis spore and mycelium extracts by different techniques with the use of pooled sera from subjects who had skin test and RAST results that were positive to P. cubensis spores.nnnRESULTSnIsoelectric focusing immunoprints revealed six common IgE-binding bands at isoelectric points 4.7, 5.0, 5.5, 5.6, 8.7, and 9.3. Two additional bands at isoelectric points 3.9 and 5.7 were detected only in the spore extract. Sodium dodecylsulfate-polyacrylamide gel electrophoresis immunoblots exhibited six common IgE-binding bands at 16, 35, 487, 52, 62, and 76 kd; 20 and 40 kd bands were present only in the spore extract. Although RAST and isoelectric focusing inhibition demonstrated that P. cubensis spore and mycelium extracts share many allergens, spores were allergenically more potent than mycelium.nnnCONCLUSIONnThe results indicate that mycelium is a useful source of P. cubensis allergen, even though several spore allergens were not detected in mycelium.

Allergic reactions to stinging and biting insects

Abstract Encounters with insects are often accidental, but not unusual, and occur relatively frequently. Allergy to Hymenoptera venom is one of the most important causes of allergic and anaphylactic reactions. Even though more than 100,000 Hymenoptera species are known, honeybee and wasp stings are the most prevalent elicitors of Hymenoptera venom allergy worldwide. Of the identified honeybee and wasp venom allergens, the nonglycosylated, species-specific major allergens Api m1 and Api m10 (honeybee), Ves v 5 and Ves v 1 (wasp), as well as few analogous venoms of other species are commercially available for diagnostic in-vitro-tests. In case of double positivity of specific serum IgE to both whole venoms these allergens and other in vitro assays may be helpful for the selection of the causative venom for specific immunotherapy. Specific immunotherapy over 3 to 5 years with insect venoms containing the important allergens is still the only causal and effective treatment of Hymenoptera venom allergy.