The management of anaphylaxis in childhood: position paper of the European academy of allergology and clinical immunology

Anaphylaxis is a growing paediatric clinical emergency that is difficult to diagnose because a consensus definition was lacking until recently. Many European countries have no specific guidelines for anaphylaxis. This position paper prepared by the EAACI Taskforce on Anaphylaxis in Children aims to provide practical guidelines for managing anaphylaxis in childhood based on the limited evidence available. Intramuscular adrenaline is the acknowledged first-line therapy for anaphylaxis, in hospital and in the community, and should be given as soon as the condition is recognized. Additional therapies such as volume support, nebulized bronchodilators, antihistamines or corticosteroids are supplementary to adrenaline. There are no absolute contraindications to administering adrenaline in children. Allergy assessment is mandatory in all children with a history of anaphylaxis because it is essential to identify and avoid the allergen to prevent its recurrence. A tailored anaphylaxis management plan is needed, based on an individual risk assessment, which is influenced by the child's previous allergic reactions, other medical conditions and social circumstances. Collaborative partnerships should be established, involving school staff, healthcare professionals and patients' organizations. Absolute indications for prescribing self-injectable adrenaline are prior cardiorespiratory reactions, exercise-induced anaphylaxis, idiopathic anaphylaxis and persistent asthma with food allergy. Relative indications include peanut or tree nut allergy, reactions to small quantities of a given food, food allergy in teenagers and living far away from a medical facility. The creation of national and European databases is expected to generate better-quality data and help develop a stepwise approach for a better management of paediatric anaphylaxis.     

Laboratory tests for diagnosis of food allergy: advantages,disadvantages and future perspectives

Numerous biological tests point to the diagnosis of food sensitization: detection of specific IgEs by Rast techniques, multi-detection assays, immunoblotting, screening of basophil activation (BAT or FAST), assays for leukotriene LTC4 release (CAST), measurement of plasma histamine, serum tryptase, serum ECP, urinary EDN, completed by mannitol-lactulose test evaluating intestinal permeability, assay of fecal IgEs, Rast for specific IgG4. Primary screening for anti-food IgEs by multi-detection assays seeks justification from insufficient clinical data and false positive tests are common in patients sensitized to pollens or latex, on account of in vitro cross reactivities (CR). Multiple CR explain positive Rast to vegetal food allergens in such patients. Biological tests should not be performed as the first line of diagnosis. In vivo sensitisation is assessed by positive prick-tests, demonstrating the bivalence of allergens, as well as the affinity of specific IgEs, two conditions necessary to bridge membrane bound specific IgEs, leading to the release of mediators. Prick-tests are closer to clinical symptoms than biological tests. However, the diagnosis of food allergy is based on standardised oral challenges. Exceptions are high levels of specific IgEs to egg (> 6 kUl/l), peanut (> 15 kUl/l), fish (> 20 kUl/l) and milk (> 32 kUl/l), reaching a 95% predictive positive value. Rast inhibition tests are useful to identify masked allergens in foods. Research developments will have impact on the development of new diagnostic tools: allergen mixes reinforcing a food extract by associated recombinant major allergens, multiple combination of recombinant allergens (chips) or tests with synthetic epitopes aimed a the prediction of recovery. Laboratory tests take place in the decision free for the diagnosis for the food allergy and the follow-up of the levels specific IgEs is a tool to assess outcome and contributes to predict recovery or persistent allergy. Up to now the significance of positive laboratory tests showing the implication of IgEs is at the crossroads of the allergist's and biologist's expertise.     

Chloroquine hypersensitivity syndrome

Chloroquine is widely used for antimalarial prophylaxis. We report the first case of delayed hypersensitivity syndrome associated with fever, digestive symptoms, bullous eruption, and eosinophilia due to chloroquine as proven by drug history and a positive patch-test for chloroquine.     

Value of ultrasound in the diagnosis of aneurysms of the extracranial internal carotid arteries

Aneurysms of the extracranial carotid arteries are a rare abnormalitiy and may represent a diagnostic challenge in examination of the patients. B-flow is a new digital vascular ultrasound technique and is an especially reliable method in the diagnosis of the extracranial portion of the internal carotid arteries as it shows less flow artifacts than color-coded Doppler sonography (CCDS) and power Doppler (PD). This review compares color-coded Doppler sonography, power Doppler and B-flow findings in extracranial ICA and CA aneurysm to emphasize the usefulness of B-flow in this clinical condition.     

Allergie à la farine de blé chez l’adulte

The clinical manifestations of allergy to wheat flour are similar to those of allergies to other foods. In adults, food-dependent exercise-induced anaphylaxis, chronic urticaria, and gastrointestinal food allergies (that is, irritable bowel syndrome, eosinophilic colitis, ulcerative colitis) are the most frequently described clinical manifestations of allergy to wheat. Wheat isolates, used as binders and emulsifiers in the food industry, are neo-allergens resulting from chemically induced desamidation of wheat gluten (heating at high temperature in an acidic medium). Wheat isolate allergens can induce severe systemic reactions (e.g., urticaria) and anaphylactic shock. Diagnosis consists of three steps: a suspicion based on the patient's history, identification of the allergen by skin testing and by laboratory tests, and confirmation by oral challenge or by an avoidance regime.     

Food allergy to wheat flour in adults

Wheat flour is a basic foodstuff. Food allergy has been especially described in children, in the form of atopic dermatitis. Food allergy in adults is rare and especially described in the form of anaphylactic shock sometimes induced by effort. Four observations of adult food allergy are presented. The IgE dependent mechanism is documented. The positive oral provocation tests needed doses of 17 to 30 grams. One crossed sensitivity between rye and barley was seen. The major allergen was probably gluten, particularly gliadines. Sensitization was probably due to prolonged inhalation of wheat flour. The authors stress the possibility of food allergy to wheat flour by other mechanisms, the difficulty of diagnosis, needed for a diet without cereal and gluten that is now non reimbursable.     

Protein hydrolysates: hypoallergenic milks and extensively hydrolyzed formulas. Immuno-allergic basis for their use in prevention and treatment of milk allergy]

Allergy to milk has an estimated incidence of 2.5%. Hypoallergenic milks are partial hydrolysates of proteins with lactose. Extensive hydrolysates of casein are mainly small peptides and do not include lactose in their formula. A primary allergenicity as well as a cross-sensitivity are shown for all partial hydrolysates. Even extensive hydrolysates have a weak potential of cross-allergy. The prevention of cow's milk allergy in infants at peculiar risk, born from atopic parents, is based on breast-feeding and/or partial or extensive hydrolysates. There is no conclusive evidence for the usefulness of eviction of dairy products during pregnancy or during the period of breast-feeding. The treatment needs exclusively extensive casein hydrolysates ensuring a 90% protection with 95% confidence intervals. Predictive prick tests in certain cases may help the choice of another hydrolysate. Severe cases with failure to thrive or multiple food intolerance require an amino-acid based formula (Neocate). A rational diversification of the diet is advised in order to prevent the onset of a multiple food intolerance syndrome which could avert from the recovery of cow milk allergy.