Hypersensitivity to Vespula and Polistes: can we tell the primary sensitization from the clinical history?

OBJECTIVE: To study the relationship between the primary sensitization to wasp venoms and the geographical and seasonal circumstances of the anaphylaxis-induced sting. METHODS: We performed a retrospective review of 115 patients (age 10-80) who suffered a systemic reaction to a wasp sting. Season and type of locality (urban or rural) at the moment of the sting were recorded. Serum specific IgE levels to venoms from Vespula and Polistes were measured, and a primary sensitization was determined to whichever genus of wasp for which the highest class of specific IgE was observed. The primary sensitization in relation to the type of locality and the season was assessed using the chi-square test. RESULTS: Most reactions occurred in urban areas (67.8 %), and in the summer season (63.4 %). Most patients were sensitized to Vespula venom (94.8 %). Primary sensitization was to Vespula in 56.5 %, to Polistes in 10.4 %, and undetermined in 33 %. The distribution of geographical areas did not show significant differences in relation to primary sensitization (p > 0.05). Most patients with primary sensitization to Vespula suffered the anaphylaxis-induced sting after the spring season, with a statistically significant result (p < 0.05). CONCLUSION: In our population, the probability of Vespula sting is higher than Polistes sting when the reaction occurs after spring. This finding can help us to identify the responsible vespid when the diagnostic tests do not provide an accurate result.

Systemic reactions to wasp sting: is the clinical pattern related to age, sex and atopy?

BACKGROUND: The aim of this study was to analyze the frequency of clinical features and the severity of systemic reactions to wasp stings, and to establish their relationship with mean age, sex, and atopy. METHODS: We studied 115 patients who suffered an anaphylactic reaction to wasp sting and showed specific IgE to venoms from Vespula and/or Polistes. In all patients, age, sex and personal history of atopy were registered. Cutaneous, respiratory, cardiovascular and gastrointestinal involvement during the course of the reaction was investigated. Each patient was assigned a severity grade according to a simple two-grade classification based on Müller's criteria. Bivariable analysis was performed to analyze the associations among mean age, sex and atopy and the symptoms and severity of the reaction. RESULTS: The mean age was 40.2 years. There were 60 males (52.2 %) and 55 females (47.8 %). Twenty-six patients (22.6 %) were atopic. The percentages of involved systems were as follows: skin 90.4 %, respiratory 54.8 %, cardiovascular 33.9 %, and gastrointestinal 21.7 %. Reactions were mild in 40.8 %, and severe in 59.1 %. The mean age was higher in patients without cutaneous symptoms (p < 0.05). Cardiovascular involvement was more frequent in males (p < 0.05). No other significant differences were found. CONCLUSION: The symptoms of systemic reactions to wasp venom most frequently involved the skin, while reactions without cutaneous involvement were more frequent in older patients. Cardiovascular involvement was more common in males. The clinical pattern was not determined by atopy and the variables studied were not related to severity.

[Exercise-induced anaphylaxis syndrome]. / Síndrome de anafilaxia inducida por ejercicio.

In the last two decades a growing incidence of a peculiar form of anaphylaxis that only occurs while carrying out physical exercise has been observed. Within the exercise-induced anaphylaxis syndrome two well differentiated clinical forms are included: systemic cholinergic urticaria and exercise-induced anaphylaxis in the strict sense which can be shown by a classic form or a variant form, more uncommon and with manifestations similar to cholinergic urticaria. Postprandial or food-dependent exercise-induced anaphylaxis is a frequently identified subtype of these last cases. It can be due to an asymptomatic food allergy manifested through physical effort, although in many occasions it is not possible to find a responsible allergen. The diagnosis is settled on the clinical history and specific tests with food allergens. It can be necessary to perform an exercise challenge test with and without previous ingestion. The treatment is preventive and it is based on avoiding the food or the food allergen some hours before the exercise. When it does not depend on foods it is used a prophylactic pharmacotherapy with antihistamines, cromones or sodium bicarbonate. The patient should be well educated on the use of epinephrine in the event of new reactions.

Anaphylactic reaction to young garlic.

BACKGROUND: Garlic is well known to cause contact dermatitis and asthma. However, it is a very rare cause of food allergy. We present the case of a 23-year-old woman with previous history of allergy to pollen and dried fruit, and food-dependent, exercise-induced anaphylaxis for which no specific food could be identified as responsible, who experienced an anaphylactic reaction after eating young garlic. METHODS: Skin prick tests and specific IgE immunoassay with several pollens and foods were performed, as well as the prick-prick test with young garlic and SDS-PAGE followed by immunoblotting IgE to young garlic and other Liliaceae species, mustard, sesame, parsley, celery, hazelnut, almond, and pollen of birch and mugwort. RESULTS: Skin prick tests and specific IgE were mainly positive for grass, plane tree, and mugwort pollen; peanut; hazelnut; walnut; almond; and mustard. Prick-prick tests with young garlic and garlic were positive. Total IgE was 113 U/ml. SDS-PAGE immunoblotting showed IgE-binding bands at 12 kDa to young garlic, garlic, onion, and leek extracts. Similar bands could also be detected with mugwort pollen and hazelnut extract. CONCLUSIONS: We describe IgE-mediated reaction to young garlic in a patient sensitized to pollen and dried fruit.