A solid-phase radioimmunoassay for detection of human antibodies. I. Measurement of IgG antibody to bee venom antigens.

A solid-phase radioimmunoassay (SPRA) has been developed to measure IgG antibodies to bee venom (BV) and phospholipiase A2 (PLA) in human sera. The principle of the test is similar to that of the radioallergosorbent test (RAST) measuring IgE antibody. Cyanogen-bromide-activated paper discs coupled with BV or PLA followed by supplementary coupling with human serum albumin were incubated with standard or test sera, washed, and incubated with 125I-labeled anti IgG. The serum levels of the IgG antibody have been temporarily expressed in arbitrary units. the reaction between the antigen and antibody was specific and the results were reproducible. Sera from 19 beekeepers, 42 beesting-sensitive patients and 20 blood donors (controls) were assayed by the SPRA. IgG antibodies to BV and PLA could not be detected (less than 4 U/ml) in all control sera, in 25 of the 42 patients and in one beekeeper. The IgG antibodies in 17 patients ranged between 5 to 58 U/ml (mean 7.6 U/ml), and in the 18 beekeepers ranged between 8 to 160 U/ml (mean 59 U/ml).

Stinging insect allergy.

Insect sting anaphylaxis is a relatively common problem estimated to affect at least 0.4% of the population and is responsible for at least 40 deaths per year in the United States. The allergic reactions are mediated by IgE antibodies directed at constituents in honeybee, yellow jacket, hornet, and wasp venoms. In addition, increasing numbers of reactions occur from fire ant stings, non-winged Hymenoptera present in the Southeastern United States. The anaphylactic symptoms are typical of those occurring from any cause. Most reactions in children are mild, frequently involving dermal manifestations (hives, edema) only. The more severe reactions, such as shock and loss of consciousness, can occur at any age but are relatively more common in adults. Following sting anaphylaxis, approximately 50% of unselected patients will continue to have allergic reactions to subsequent stings. The natural history of the disease process is influenced by the severity of the anaphylactic symptoms. Children with dermal reactions only have a benign course and are unlikely to have recurrent reactions. Patients with more severe reactions are at risk for repeat anaphylaxis. Patients with a history of insect sting anaphylaxis and positive venom skin tests should have epinephrine available and are candidates for subsequent venom immunotherapy, which provides almost 100% protection against subsequent re-sting reactions. Recommendations for the duration of immunotherapy are evolving. Venom therapy can be stopped if skin test reactions become negative. For most patients, 3 years of therapy appears adequate, despite persistence of positive venom skin tests.

Comparison of the biochemical, immunologic and allergenic properties of vespid venoms collected in early and late summer.

The biochemical, immunologic and allergenic properties of yellow hornet (Vespula arenaria) and bald-faced hornet (Vespula maculata) venoms collected in early and late summer were compared. The phospholipase A content of both hornet venoms decreased in late summer while protease, hyaluronidase and acid phosphatase contents were unchanged. The antigenic and allergenic properties of the two venoms, as measured by their reaction with rabbit antisera and sera from insect-allergic patients, respectively, were unchanged. These results suggest no changes in venom properties during the summer which influence the allergic response to insect stings.

Phospholipase A2 in venom extracts from honey bees (Apis mellifera L.) of different ages.

We measured phospholipase A2 activity in the venom of worker honey bees (Apis mellifera L.) of known ages using chemical (titrimetric) and radioallergosorbent methods. The two techniques give similar results. Low levels of phospholipase A2 are present in the venom system at the time of eclosion. Phospholipase A2 activity in the venom increases steadily through the 10 days after eclosion. Maximal phospholipase A2 levels (about 40 micrograms phospholipase A2/venom sac) are maintained through the rest of the life of a worker bee in summer.

Stinging insect allergy: changing concepts.

Immunologic advances promise changes in the approach to diagnosis and treatment of Hymenoptera stings. Results of skin tests with venom show good correlation with those of in vitro tests (histamine release and radio-allergosorbent test [RAST]). Similar comparisons of whole-body extract (WBE) skin tests with in vitro tests show poor correlation. Treatment emphasis must currently be placed on sting prevention and on medical treatment. The only material now available commercially for immunotherapy is WBE. Circumstantial evidence suggests some benefit from immunotherapy with WBE, but immunologic data do not support this observation.

Late onset reactions following venom immunotherapy and venom skin tests.

This report describes patients who had late onset reactions following venom immunotherapy and venom skin tests. Six adult patients had symptoms of fatigue, malaise, fever, headache, and joint ache, starting four to six hours after venom immunotherapy and lasting up to four days. Two of the patients had prolonged reactions at or adjacent to the skin test sites. All of these patients had a history of venom anaphylaxis; four had severe cardiovascular symptoms. All received yellow jacket venom immunotherapy and four honeybee venom immunotherapy. In four patients, the reactions occurred following small venom doses, 0.1 to 2 micrograms. Two patients reacted after maintenance doses of 50 micrograms. There was no relationship to the serum IgE or IgG antibody titers. All but one patient had serum venom-specific IgE but the titers covered a wide range. Serum venom-specific IgG was present in four patients. There was no response in lymphocyte culture to bee venom stimulation in two patients. Two of these patients stopped venom immunotherapy; one had reached the maintenance dose. In three patients, prophylactic parenteral steroids have ameliorated the reactions. After a temporary dose reduction, the sixth patient is now asymptomatic. A seventh patient developed asthma, 12 hours following a maintenance dose of 50 micrograms of yellow jacket venom. Concomitant steroid administration has effectively prevented the reaction. Another patient, a 6-year-old boy, developed fever, edema of the face and lips, erythema of the leg, and a large, tender right inguinal node eight hours following venom skin tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Unusual reactions to insect venoms.

A variety of unusual, unexpected reactions have been described that occur in a temporal relationship to venom exposure, primarily insect stings. An immunologic mechanism appears responsible for reactions such as serum sickness and late onset allergiclike symptoms. In all probability, allergic mechanisms are responsible for the renal and neurologic symptoms and the delayed hypersensitivity type reactions. The mechanisms for the fatigue and malaise following venom injections and the most unusual areas of extensive erythema following venom skin tests are not known.

Do air cleaners make a difference in treating allergic disease in homes?

LEARNING OBJECTIVES: The purpose of this review is to objectively critique available data regarding the clinical benefits of room air cleaners and to provide physicians and patients with a reasonable recommendation of their utility in treatment of inhalant allergic disease. DATE SOURCES: Data were obtained from published studies and reviews. STUDY SELECTION: The specific reviewed studies met the following criteria: 1) selection of patients with clinical allergic disease confirmed by detection of allergen-specific immunoglobulin E; 2) use of an effective air filter; 3) clinical and laboratory evaluation of results; and 4) measurement of the results of air filtration on environmental allergen or airborne particulate levels. The studies were conducted in a double-blind manner. Conclusions of two previous reviews are also incorporated in this paper. RESULTS: The results of the published studies and summary reviews show minimal, if any, effectiveness of room air cleaners in treatment of allergic respiratory disease. CONCLUSIONS: Room air cleaners should not be recommended for people with inhalant allergic disease.

Studies of the natural history of insect sting allergy.

The natural history of insect sting allergy was studied by observations of the results of re-sting on two groups of individuals who had prior sting anaphylaxis, had demonstrable venom-specific IgE, and did not receive venom immunotherapy. In the first study group, the mean duration between the initial sting reaction and re-sting exposure was 4.5 years; the re-sting reaction rate was 35%/sting and 50%/patient. In the second long-term study, the mean duration between the sting reaction and re-sting was 7.3 years; the re-sting reaction rate was 12%/sting and 12%/patient. Factors influencing the likelihood of re-sting reaction included older age, and the occurrence of cardiovascular/respiratory anaphylactic symptoms. In a prospective and retrospective study of 133 patients with large local reactions, re-sting observations indicated an extremely high recurrence of similar large local reactions, with little risk of subsequent anaphylaxis. These data suggest that: (1) insect sting anaphylaxis is a self-limiting process for the majority of individuals, and (2) re-stings in individuals who have had large local reactions have a relatively benign prognosis.

Duration of venom immunotherapy: relationship to the severity of symptoms of initial insect sting anaphylaxis.

BACKGROUND: This study assessed the postulate that the adequate duration of venom immunotherapy (VIT) is related to the severity of the initial sting anaphylactic symptoms. METHODS: Data were collected from patients with venom allergy who had sting anaphylaxis and subsequent positive venom skin test results, received maintenance VIT, and had field re-stings after cessation of VIT. There were 217 re-stings in 113 patients with 15 systemic reactions in 10 patients (a re-sting reaction rate of 9% per sting and 7% per patient). RESULTS: Re-sting reactions occurred in 1 of 25 patients with initial mild anaphylaxis (4%), 2 of 41 patients with moderate reactions (5%), and 7 of 47 patients with initial severe symptoms (15%). The results were not influenced by the duration of VIT or the interval between cessation of VIT and the re-sting. Eighteen patients who converted to negative skin test reactions had no reactions when re-stung. CONCLUSIONS: These results suggest a relationship between the severity of anaphylaxis and subsequent duration of VIT. Two to three years is sufficient for patients who had mild to moderate anaphylaxis. Longer duration of therapy is advisable for patients who had severe symptoms and continue to have positive venom skin test results.

Natural history of insect sting allergy: relationship of severity of symptoms of initial sting anaphylaxis to re-sting reactions.

To examine the postulate that the nature of the symptoms of initial insect sting anaphylaxis is related to the risk and severity of subsequent sting reactions, the results of field re-stings were analyzed in 220 patients who had had venom anaphylaxis and did not receive venom immunotherapy. The incidence of a reaction after the first re-sting was 56% in the total group, was more frequent in adults (74%) than in children (40%), and was unrelated to the time interval since the initial sting reaction. When re-sting reactions did occur, the nature of the symptoms was similar to the symptoms of the initial sting reaction. Reactions to repeated re-stings tended to be similar. Overall, more severe reactions to re-stings occurred eventually in 24 patients. These observations confirm the frequent self-limiting course of insect sting allergy, especially in children, and the repetitive nature of specific anaphylactic symptoms, and the observations thus suggest that patients with mild to moderate anaphylactic symptoms probably do not require venom immunotherapy.

Allergic reactions following first insect sting exposure.

Over a 10-year period, 750 patients were evaluated because of anaphylaxis following insect stings. Sixty-five patients were identified who had reactions after their first sting exposure. Their clinical features and symptoms of anaphylaxis were the same as the much larger group of patients who had allergic reactions following prior exposure to insect stings. When evaluated following the sting reaction, the majority of these patients had venom-specific IgE detected by skin test or in the serum by the RAST. Fifty-three re-stings occurred in 31 patients. In untreated or whole body extract-treated patients, there were 43 re-stings resulting in 13 reactions. There were no reactions following 10 re-stings in venom-treated patients. In a subgroup of 15 patients with undetectable venom-specific IgE, there were 16 re-stings in eight patients, leading to three systemic reactions. The occurrence of allergic reactions following first sting exposure adds further support to the thesis that some sting reactions are non-IgE-mediated.