The efficacy and safety of sublingual immunotherapy (SLIT) are currently supported by clinical trials, metaanalysis and post-marketing surveys. Practice parameters for clinical use of SLIT are proposed here by a panel of Italian specialists, with reference to evidence based criteria. Indications to SLIT include allergic rhinoconjunctivitis, asthma, and isolated conjunctivitis (strength of recommendation: grade A). As to severity of the disease, SLIT is indicated in moderate/severe intermittent rhinitis, persistent rhinitis and mild to moderate asthma (grade D). SLIT may be safely prescribed also in children aged three to five years (grade B), and its use in subjects aged more than 60 years is not prevented when the indications and contraindication are ascertained (grade D). The choice of the allergen to be employed for SLIT should be made in accordance with the combination of clinical history and results of skin prick tests (grade D). Polysensitisation, i.e. the occurrence of multiple positive response does not exclude SLIT, which may be done with the clinically most important allergens (grade D). As to practical administration, co-seasonal, pre co-seasonal, and continuous schedules are available, being the latter recommended for perennial allergens or for pollens with particularly prolonged pollination, such as Parietaria (grade D). For pollens with relatively short pollination, such as grasses and trees (cypress, birch, alder, hazelnut, olive) the pre coseasonal and perennial schedules are preferred (grade C). The build-up phases suggested by manufacturers can be safely used (grade A), but they can be modified according to the patient’s tolerance (grade C). A duration of SLIT of 3-5 years is recommended to ensure a long-lasting clinical effect after the treatment has been terminated (grade C).

Summary Background Maize allergy is not very common especially in Europe. The number of studies that address IgE mediated maize allergy is all too few. Objective Evaluate subjects with a history of maize allergy by double‐blind, placebo‐controlled food challenge; identify the spectrum of symptoms manifested during challenge; determine the lowest provocation dose (PD) during challenge; determine the performance characteristics of maize skin prick test and specific IgE. Methods Twenty‐seven patients with a history of maize allergy were enrolled to be evaluated by skin test, specific IgE and double‐blind placebo‐controlled maize challenge. Results Forty‐eight percent of the patients were challenge positive. PD range was 0.1–25 g. Fifty‐four percent of the maize allergic subjects had a PD that was 2.5 g; two subjects reacted to 100 mg of maize. Comparison of maize specific IgE levels and skin test results to the challenge results revealed the following (specific IgE level/skin testing): sensitivity 1.00/0.846, specificity 0.077/0.384, positive predictive value 0.520/0.579, and negative predictive value 1.00/0.714. Conclusion Maize is a cause of IgE‐mediated allergic reactions to foods in adults and children. Nearly half of the subjects recruited were confirmed by challenge to be allergic to maize. Twenty‐three percent of the positive challenge patients manifested symptoms that involved two organ systems, thus fulfilling the criteria for maize induced anaphylaxis. Maize is allergenic and can pose a risk for symptomatic food allergy at a dose of 100 mg.

The current burden of allergic diseases, estimated by both direct and indirect costs, is very relevant. In fact the cost estimation for rhinitis amount globally to 4-10 billion dollars/year in the U.S. and to an average annual cost of 1089 euros per child/adolescent and 1543 euros per adult in Europe. The estimated annual costs in Northern America for asthma amounted to 14 billion dollars. Consequently, preventive strategies aimed at reducing the clinical severity of allergy are potentially able to reduce its costs. Among them, specific immunotherapy (SIT) joins to the preventive capacity the carryover effect once treatment is discontinued. A number of studies, mainly conducted in the US and Germany demonstrated a favourable cost-benefit balance. In the nineties, most surveys on patients with allergic rhinitis and asthma reported significant reductions of the direct and indirect costs in subjects treated with SIT compared to those treated with symptomatic drugs. This is fully confirmed in recent studies conducted in European countries: in Denmark the direct cost per patient/year of the standard care was more than halved following SIT; in Italy a study on Parietaria allergic patients demonstrated a significant difference in favor of SIT plus drug treatment for three years versus drug treatment alone, with a cost reduction starting from the 2nd year and increasing to 48% at the 3rd year, with a highly statistical significance which was maintained up to the 6th year, i.e. 3 years after stopping immunotherapy, corresponding to a net saving for each patient at the final evaluation of 623 euros per year; in France a cost/efficacy analysis comparing SIT and current symptomatic treatment in adults and children with dust mite and pollen allergy showed remarkable savings with SIT for both allergies in adults and children.

The increasing development of new health care technologies, along with the ageing of the population and the increasing patients' expectations, cause a significant raise in medical costs, inducing in policy makers the need for well-funded information to support their decisions. The development of Health Technology Assessment (HTA), which is the systematic evaluation of properties, effects or other impacts of health technology and can be considered as a bridge between the world of research and the world of policy-making, reflects this high level of demand. HTA requires a multidisciplinary approach, that covers many different disciplines, in order to assess various aspects of health technologies, as technical properties, safety, efficacy/effectiveness, economic aspects, social, legal, ethical and political impacts. Allergic diseases show a worldwide increasing prevalence and consequent increasing costs, which result very high in recent evaluations. Specific immunotherapy is the only treatment able to alter, differently from drugs, the natural course of allergic diseases, exerting a long-lasting therapeutic effect, that persists also after stopping the therapy. This has a potential great impact in the cost of disease, which only recently was considered in properly designed studies. These issues claim for a larger use of HTA, which may provide a more comprehensive approach to the evaluation of the impact of immunotherapy on allergic patients.

Allergic rhinitis and asthma constitute a global health problem because of their very high prevalence and the consequent burden of disease, concerning medical and economical issues. Among the treatments of allergy, specific immunotherapy has the capacity to favourably alter the natural history of the disease both during and after its performance and thus to reduce the direct and indirect costs of allergic rhinitis and asthma. A number of studies reported such cost reduction for traditional, subcutaneous immunotherapy and recent data demonstrate that also sublingual immunotherapy (SLIT) is associated to economic advantages and/or monetary savings, specifically in terms of reduction of disease economic burden. Only few formal economic assessments of SLIT have been carried out so far, this article will present and discuss the published studies addressed to this issue. The data obtained, although the number of studies is still limited, provide preliminary evidence supporting a SLIT effect on sparing costs for respiratory allergy.

Background: Wheat is believed to be an uncommon cause of food allergy in adults; the number of studies that address IgE mediated wheat allergy in adults is all too few.Objective: Determine how many subjects with a history of wheat allergy have real allergy by double-blind, placebo-controlled food challenge; identify the symptoms manifested during the challenge; determine the lowest provocation dose; determine the performance characteristics of wheat skin prick test and specific IgE; identify subjects with real wheat allergy for potential immunoblotting studies.Methods: Patients underwent skin test with commercial wheat extract; specific wheat IgE was determined. Subjects were challenged with 25 g wheat. Subjects who were positive to raw wheat challenge underwent cooked wheat challenge. Results: Thirty-seven double-blind placebo-controlled wheat challenges were performed on 27 patients. A total of 13 of 27 (48%) patients had a positive result. Eleven subjects with positive raw wheat challenge underwent cooked wheat challenge: 10 were positive. The provocation dose range was 0.1 to 25 g. Twenty-seven percent of the subjects allergic to wheat had a provocation dose that was <= 1.6 g.Conclusion: Wheat causes real food allergy in adults. More than a quarter of the patients allergic to wheat reacted to less than 1.6 g wheat. Specific IgE was more sensitive than skin test for wheat; however, specificity and predictive values were low for both tests. Thus, these tests should not be used to validate diagnosis of wheat allergy.

BACKGROUND:Food allergy to wheat and maize is an increasing factor of deterioration of life quality, especially childhood and can, in rare cases, even induce anaphylaxis. Although omega-5 gliadin from wheat and maize lipid transfer protein have been characterized as major cereal allergens on the molecular level, the list of food allergens is far to be complete.METHODS:To identify the IgE-binding repertoires of wheat and maize we screened respective cDNA libraries displayed on phage surface with sera from patients with a confirmed food allergy. The study included six patients with a positive double-blind, placebo-controlled food challenge (DBPCFC) to wheat, nine patients with a positive DBPCFC to maize, and six patients with anaphylactic reactions after ingestion of wheat.RESULTS:The enriched sequences encoding IgE-binding proteins showed heterogeneous repertoires for both, wheat and maize. The selected wheat repertoire yielded 12, the maize repertoire 11 open reading frames. Among these we identified allergens belonging to already characterized allergens families, such as gliadin, profilin and beta-expansin. Besides, we found novel proteins with high cross-reactive potential, such as thioredoxins, as well as sequences that had so far not been related to cereal allergy at all. The IgE-binding capacity of some selected proteins was evaluated in vitro and cross-reactivity was demonstrated by competition ELISA.CONCLUSION:With regard to the heterogeneity of the characterized sequences as well as to the biochemical nature of the new allergens detected we conclude that wheat and maize-related food allergy is more complex than so far anticipated.

RATIONALE: To assess costs and consequences of sublingual immunotherapy (SLIT) in association with continuous symptomatic treatment (CST) for allergic rhinitis and atopic asthma compared to CST alone, in the societal perspective. METHODS: The study was based on a decision-tree analytical model, using epidemiological and resource utilization data collected among 25 specialist centres on 2200 patients. Comparative data are presented for a theoretical cohort of 1000 adult patients affected by pollen allergy, per study arm. Cost analysis comprised ambulatory visits, tests, hospitalisations, drugs, SLIT, lost productivity and out-of-pocket expenses. Effectiveness results are presented as number of improved patients and asthma cases avoided, over a 6 years timeframe. Sensitivity analysis was performed by varying costs and epidemiological data. RESULTS: In comparison with CST alone, SLIT-CST improves the symptoms of 399 extra patients and avoids 229 patients to become asthmatics. SLIT-CST strategy is also cheaper than CTS with an average cost/patient over 6 years, of €4,313 and €6,426 respectively. Therefore, SLIT-CST resulted less costly and more effective, i.e. dominant over CTS. CONCLUSIONS: Allergic rhinitis and atopic asthma represent an increasing public health concern. The relevance of SIT in atopic disease is established by the latest recommendations of the ARIA group. Our study provides information about the costs and consequences of SLIT-CST compared to CST in pollen allergy in adults. In our approach, the pharmaco-economic profile of SLIT was very favourable and demonstrated that SLIT-CST is more effective and saves resources vs. the alternative.

RATIONALE: Soybean belongs to the "big eight" allergenic foods. The identification and characterization of soy allergens helps to improve diagnosis. METHODS: 28 patients from Switzerland, Denmark and Italy were included on the basis of a positive DBPCFC (n=23) or a history of anaphylaxis to soy (n=5). IgE-reactive peptides were identified from a soybean cDNA expression library. Full-length purified recombinant and natural soybean allergens, and soyflakes extract were investigated in IgE-immunoblotting. RESULTS: From the cDNA library the major storage proteins glycinin (A1aB1b, A2B1a), and the 3 subunits of beta-conglycinin were IgE-reactive. Patients' IgE bound to recombinant and natural glycinin (>20%), to recombinant and natural beta-conglycinin (>20%), to natural (>50%) but not to recombinant Gly m Bd 30k. CONCLUSIONS: The IgE-binding profiles in soyflakes extract were complex and highly individual. Purified natural and recombinant soy proteins improved identification of IgE-reactive soy proteins. Glycosylation and/or folding properties seem to influence IgE-binding of Gly m Bd 30k that is thought to be a major soybean allergen.

BACKGROUND:Economic evaluations are increasingly relevant in order to provide support for decision makers when judging about alternative ways to allocate public funds. Aim of this study was to evaluate the economic effect of treatment with high dose sublingual immunotherapy (SLIT) in children.METHODS:The study involved one allergy center, located in the north of Milan, Italy. From the existing records of patients seen for allergic disease, we extracted all children and adolescents with allergic disease, who had 1-year data prior to receiving SLIT and 3-year data on SLIT. Outcome measures (number of exacerbations, visits, absence from nursery or school), direct costs (euros spent on drugs, specialist visits, SLIT) and indirect costs (costs resulting from children school and parental work loss) were analysed. A second analysis compared a sub-group of allergic asthmatic children with a control group for costs, based on records of patients not SLIT-treated, extracted from a network-database of paediatricians.RESULTS:135 patients were extracted, of which 46 had perennial, and 89 had seasonal allergy with comparable gender and age distribution. A substantial reduction was found in all outcome measures during SLIT compared with the before period. The average annual cost/patient was 2672 before SLIT initiation and _629/year during SLIT. Similar results were found for allergen subgroups. The asthma sub-analysis involved 41 children with SLIT and 35 controls. Again, SLIT patients showed a substantial reduction in outcome measures; the direct cost/patient over the whole follow-up (4 years) was _1182 for SLIT patients and _1100 for controls.CONCLUSION:High dose SLIT may be effective in reducing the cost of allergic rhinitis and asthma and comparably expensive to conventional treatment in children with allergic asthma over a 4 years follow-up.

Conclusions High dose SLIT may be effective in reducing both the clinical and economic burden of allergic disease in children and adolescents.

At present, the double blind placebo controlled food challenge (DBPCFC) represents the only way to establish or rule out an adverse reaction to a food in older children and adults, whereas an open challenge controlled by trained personnel is sufficient in infants and young children (1). The challenge procedure is not, however, fully developed and no standardised procedure has so far been agreed upon, although a manual describing several of the issues has previously been published (2). For the safety and feasibility of the patient undergoing challenge there is a need for standardisation of the procedures. Standardization also allows for comparison of results between different centers and different populations in scientific protocols. This Position Paper gives advice on how the procedures can be performed, but since there are no direct comparative studies available in the literature directly comparing the various parameters (e.g. timing between two subsequent challenges or increment of the dose for challenge) we have not been able to recommend truly evidence based guidelines. It is also important to realize, that legislative aspects vary in different countries within Europe, and that the guidelines presented herein must be adjusted according to local legislation. Furthermore this guideline does not constitute a guideline for Ethics Committees to decide feasibility of DBPCFC in a scientific protocol. There are several issues to be determined, prior to commencing a challenge in a patient. These can be divided into patient-related parameters, which are parameters concerning the actual patient in question and procedure-related parameters, which deal with the parameters independent of the patient in question (Table 1). Challenge should be performed either for establishment or exclusion of the diagnosis, for scientific reasons in clinical trials or for enabling determination of the sensitivity of the actual patient (threshold value) or for determining the allergenicity of foods. The determination of the sensitivity both enables tailor-made guidelines for the patient and opens the possibility of following sensitivity by repeated challenges especially in children with food allergies normally outgrown during childhood (cow's milk or hen's egg). Patients should be investigated according to the EAACI guidelines (1) using case history combined with in vivo and in vitro testing supplemented with a elimination diet period prior to challenge when necessary. Based on the findings here, the patient-related parameters can be determined. The guidelines in this position paper focus mainly on patients presenting classical immediate type allergic symptoms and signs (IgE-mediated type I allergy), as defined in EAACI position paper (1). Patients of any age with a history of adverse reaction to a food: For establishment or exclusion of the diagnosis of food intolerance/allergy For scientific reasons in clinical trials For determination of the threshold value or degree of sensitivity For assessment of tolerance. Once diagnosed, when a patient is suspected to have outgrown his clinical allergy – especially in children, whose food allergies normally outgrow during childhood, e.g. cow's milk or hen's egg allergies. Patients without specific history of adverse reaction to a food: If any chronic symptom is suspected by the patient or the physician to be food-related If a patient is on an improper elimination diet - without history of adverse food reaction –, the food has to be reintroduced and there are reasons for suspecting that an adverse reaction is possible. If a sensitization to a food is diagnosed and tolerance is not known – for example, sensitization to cross-reactive foods that have not been eaten after the adverse reaction. Eliglible patients for DBPCFC include: All patients with suspicion of an immediate, systemic allergic reaction to a food for establishment or exclusion of the diagnosis in infants and children ≤three years, an open challenge controlled and evaluated by a physician is most often sufficient. Patients with pollen related oral allergy syndrome (5) as their only symptom should only undergo DBPCFC outside scientific protocols in selected cases; for example in cases with discrepancy between case history and outcome of in vivo and/or in vitro tests. An open challenge may precede DBPCFC in older children and adults because a negative result herein renders DBPCFC unnecessary. Open challenges should not be applied in cases with a high probability of a positive outcome or in cases with subjective and/or controversial symptoms only (6). There are, however other types of patients, who also should be investigated in a standardised programme: patients with isolated, late reactions such as a subgroup of patients with atopic eczema dermatitis syndrome (AEDS) (7–12). In the majority of AEDS patients with associated food hypersensitivity an immediate reaction is seen (eg exanthema, flushing, urticaria together with symptoms and signs from the respiratory and gastrointestinal tract), but data are accumulating on a subgroup of patients who only experience exacerbation of their eczema within 24–48 hours after challenge. In such patients, the challenge procedure should be adjusted to meet the demands concerning e.g. timing and settings (11–15). patients with controversial symptoms often of subjective nature such as chronic fatigue syndrome, multiple chemical sensitivities, migraine or joint complaints, who are presenting symptoms which are not in accordance with classical atopic symptoms. Such patients should only be investigated in strict scientific protocols with special attention to the statistical evaluation of the outcome, see ''Statistics section''(6). patients with chronic urticaria, where a subgroup is reactive to additives or to high doses of special foods (e.g. tomatoes) (16–24). Standardised protocols for DBPCFC in these patients have so far not been fully developed, and the actual incidence of food dependent chronic urticaria remains to be established. patients with isolated late reactions in the gut (25, 26). Also for this group of patients, special attention must be paid to the lack of knowledge of incidence and nature of reaction, since these patients have not been finally classified. Specific guidelines for these four latter groups are not dealt with in this Position Paper. In these patients, the challenge procedures must be adjusted according to the nature and severity of the reactions. Detailed guidelines for such patients have so far not been developed within the EAACI. A detailed position paper which has just been published from the German Society of Allergology and Clinical Immunology for identification of the late reactions in AD is now being modified for the EAACI (13). Challenge is thus performed when the diagnosis is not made by case history and outcome of in vivo/in vitro tests, in scientific protocols for research purposes, or when a patient is suspected to have outgrown his/her clinical allergy. Patients with a clear cut case history of anaphylaxis (or a severe systemic reaction) to one or more specific food items should not be challenged, provided the risk of misinterpretation of a positive skin prick test or specific IgE due to clinically insignificant cross reaction is considered and ruled out - this may be the case for instance in patients with a false positive specific IgE to peanut due to grass pollen sensitization (27). The potential risk to the patient must always be weighed against the risk of misinterpreting e.g. skin prick test results or positive findings in specific IgE. We define Anaphylaxis according to EAACI 2002, comparable to class 3 to 4 in the Müller classification of reactions to bee or wasp (28). In selected cases where positive test results makes challenge unnecessary as is the case in children with positive spt to egg and specific IgE (CAP) above a certain level from ≥0.35 KUA/L to 17.5 ≥ KUA/L, in which the probability of a positive challenge outcome exceeds 95%. At present, such a correlation has only been demonstrated in children with AEDS and allergy to selected foods (29–32). By omitting challenge, determination of the clinical sensitivity (''threshold'') of the patient is not possible (33). Patients with ongoing disease should not be challenged e.g. patients with acute infection, unstable angina pectoris or patients with seasonal allergy during the season. Patients with chronic atopic disease such as asthma or AEDS should only be challenged when disease activity is at a stable and low level. Pregnant women should not be challenged. Patients taking medication which may enhance, mask, delay or prevent evaluation of a reaction or interfere with treatment of a reaction should not be challenged. Drugs include antihistamines, neuroleptics, oral steroid above 5 mg per day, aspirin and other NSAID's, ACE-inhibitors, beta-blockers and clinical experience and new drugs may extend the list. Medication such as short acting β2-agonists, inhaled or topical steroids can normally be continued during challenge, but the amount used must be kept at a fixed level. Discontinuation of these drugs may interfere with the interpretation of the outcome of the challenge. Double blind challenge (DB) DB is the procedure generally recommended, especially if a positive challenge outcome is expected (for example, when studying an adverse reaction believed to be IgE-mediated, and the food skin test is positive). DB is the method of choice for scientific protocols. DB is the method of choice when studying late reactions or chronic symptoms, such as AEDS, isolated digestive late reactions, or chronic urticaria. DB is the only way to conveniently study subjective food-induced complains, such as acute subjective adverse reactions, chronic fatigue syndrome, multiple chemical sensitivities, migraine or joint complaints. Open challenge A negative DB should always be followed by an open challenge. A positive open challenge could be sufficient when dealing with IgE-mediated acute reactions manifesting with objective signs. For practical reasons, an open challenge can be the first approach when the probability of a negative outcome is estimated to be very high (for example, when studying an adverse reaction believed to be IgE-mediated, and a properly performed food skin test is negative). In infants and children ≤3 years, an open, physician- controlled challenge is often sufficient for suspected immediate type reactions (unless a psychological reaction of the mother is expected). For patients with pollen-related OAS as their only symptom, an open challenge could be sufficient as regular procedure - due to difficulties in blinding fruits and vegetables conserving their allergenicity -. However, in these patients, DB are recommended for scientific protocols and other selected cases for example, discrepancies between clinical history and outcome of diagnostic tests. Single Blind Challenge Single blind challenge carries the same difficulties for blinding foods as for DB, and introduces subjective biases of the observer. Therefore, with only a minor additional work (cross-over by an external technician), DB can be performed, and the result will be more robust. Therefore, our recommendation is to always use DB instead. The personnel involved in challenge procedure must be specially trained in management of acute allergic reactions and equipment for resuscitation (including adrenaline for injection and oxygen) must be readily available. In cases where a severe reaction is suspected, challenge should be performed in settings with immediate access to intensive care units. A possible need for latex-free surroundings should be considered. Placebo challenge and active challenge should ideally be separated by at least 24 hours, but when late reactions are not expected, both challenges can in many cases of classical type 1 allergy be performed on the same day. If a reaction needing treatment occurs, the next challenge should not be performed until the symptoms have resolved and the quarantine period for the drugs used has expired. Intravenous access should be available before initiation of challenges as a general rule, and always if a severe systemic reaction is expected. In small children, iv access is only necessary in selected cases, but if there is any doubt on the outcome (severity) of a challenge, it is advisable to place a cannula in advance. Patients can be in most cases be challenged as out patients and discharged after an observation period of at least 2 hours after the last dose given, provided no reaction has occurred. The observation period must be adjusted to the expected symptoms and signs in the patient in question. The patient must be discharged with specific information and satisfactory arrangements for care if a late reaction (especially asthma) occurs. In some cases, ''rescue medication'' consisting of antihistamines, β-agonists and steroids may be given to the patient to take prn after contacting the physician. If a patient experiences a severe reaction needing treatment (asthma, laryngeal oedema, severe urticaria), he/she should be kept under observation at the hospital overnight and treated accordingly. A negative outcome of DBPCFC must always be followed by an open serving of the food in order to avoid possible false negative outcome of DBPCFC due to destruction of allergens during preparation of the challenge (34). For clinical purposes, a patient may thus be classified as positive, or likely positive (only positive in open challenge) whereas as in a scientific protocol a positive open challenge in a DBPCFC negative patient should be considered as a drop-out. If case history is suggestive of reactions in special situations only (reaction elicited only when exercising after eating (food dependent, exercise induced anaphylaxis (3) or with concomitant intake of a drugs (e.g. aspirin (4)) or intake of processed food (35–37)) challenges should first be performed without exercise/drug intake and if negative repeated with exercise/drug intake . Many of these reactions are, however, severe of nature and the use of pharmaceutical ''facilitators'' such as aspirine may enhance the severity of the reaction resulting in life-threatening situations. Such challenges should always be considered carefully. The challenge protocol should be decided on beforehand. In cases of classical type 1 patients presenting objective signs a protocol using one active and one placebo is normally sufficient due to the low frequency of reactions to placebo in these patients (38–49). In more dubious cases and especially in cases patients presenting with subjective signs only a protocol with repeated challenges should be applied, either using three plus three challenges or three plus two challenges (50–53). The starting dose, ie the amount of food in question administered to the patient as the first dose should be evaluated based on patient's case history and correlated to available data from the literature (Table 2). In published papers, 5% of patients react to less than 1 mg of peanut, whereas 15% of milk allergic patients react to less than 5 ml of cow's milk (43, 54). A computer model for assessment of threshold has recently been published demonstrating a possible threshold for a reaction in one in a hundred patients for milk, egg and peanut of 0,1 mg (55). It is advisable to begin with a starting dose below the expected 'threshold dose', because this will enable determination of the actual sensitivity in the patient (low adverse effect level and no observed adverse effect level). There is no correlation between the size of a skin prick test or the level of specific IgE and the clinical sensitivity in individual patients (33, 65). A time interval of 15–30 minutes is in most cases suitable for investigation of IgE associated reactions unless using capsules. In published papers, symptoms most often occur 3 to 15 minutes after intake; especially the severe reactions always occur immediately - if the patient history claims a reaction developed later, time schedule should be adjusted accordingly (39, 42, 43, 45, 50, 56, 66, 67). All patients follow the above incremental scheme if an acute reaction is suspected, patients with suspected isolated late reactions (e.g. exacerbation of AD) continue on another protocol with intake of normal daily amount the following day settings (11–15). The increment may either be a doubling of the dose every 15–30 minutes until top dose has been reached or the patient react, or a increment using logarithmic mean ie 1, 3, 10, 30, 100 etc. No comparative studies comparing these two protocols are available. There is a theoretical risk of passive rush desensitization during the procedure, but evidence for such a phenomenon has not been published and is unlikely since this would result in a positive outcome of the open feeding following a negative DBPCFC. Such reactions have only been seen in cases, where the active substance was destroyed during the blinding procedure (34, 68). If too large increments, on the other hand, are used, the risk of severe reactions increases. Therefore, at the present state of knowledge, either doubling or logarithmic increment is recommended. The top dose ie the maximal amount administered should normally be the normal daily intake in a serving of the food in question, adjusted for the age of the patient. Data concerning the foods most often causing allergic reactions has previously been published (69). Active and placebo challenges should be identical regarding taste, looks, smell, viscosity, texture, structure and volume. Assessment of possible differences between active and placebo should be evaluated by standard procedures such as duo-test and triangle-test, where differences in taste, texture, smell etc. are compared either in pairs or by ability for finding one different between three samples (70). In infants and children liquid foods can be masked in extensive hydrolysed cow's milk based formulas or in amino acid formulas eventually with addition of flavouring agents or colourants. Items with a strong taste such as black currant juice or peppermint oil may help masking an unpleasant taste. Different recipes for masking liquid and solid foods (peanut, soy, wheat, milk, egg, fish, hazelnut, almond, brazil nut, apple, carrot, celery, apricot, banana, zucchini, crustaceans) have been developed and are available on the EAACI homepage (http://www.eaaci.org or http://www.ig-food.org.) It is of crucial importance to ensure presence and stability of the allergenicity of the food in the mixture. In cases with very stable foods such as peanut or cod (42, 71) stability in the serving is not a problem, whereas in other cases especially with foods of vegetable origin (apples) the stability is very low (72). The procedures must be adjusted according to the stability of the food in question (35, 37). Only in cases of a suspected reaction to additives is masking in gelatine capsules recommended. Capsules should else wise be avoided, since reactions in mouth and throat are bypassed (OAS) and since the whole procedure is delayed due to the lag phase when the capsule is dissolved in the stomach. Measures to avoid toxicity from the food administered should be taken (aflatoxins in brazil nuts, salmonella bacteria in eggs, and mites in flour). Different approaches should be taken in patients presenting classical allergic symptoms with objective signs of a reaction on challenge and patients presenting subjective symptoms only. Furthermore, special attention should be made to the statistical evaluation when investigating patients with controversial symptoms. In classical type I allergy reacting with objectively measurable signs (e.g. a drop in FEV1, sneezing or urticaria), reactions to placebo are relatively rare and a challenge procedure using one active and one placebo challenge is normally sufficient (40, 42, 61, 73). In contrast, the frequency of reactions to placebo seen in patients reacting with subjective symptoms (OAS, migraine, itching) is higher (50, 53). Here, repeated challenges are normally necessary. Two statistical approaches exist, necessitating different approaches in challenge procedure. This is especially true for patients only presenting subjective symptoms: 1. An approach considering the actual patient The risk of a patient guessing the right sequence of challenges by chance is 50 per cent, if one active and one placebo is administered. Therefore repeated challenges must be used to ensure statistical significance. A protocol using three active and three placebo's has been published (51). The chance of a patient guessing the right sequence by chance is 0.05 (0.5 × 0.6 × 0.5 × 0.67 × 0.5). Recently a new model has been proposed, where using five challenges in stead of six, where the patient is aware of the presence of either three active and two placebo challenges or vice versa (52). This approach holds the same statistical reliability as using six challenges. 2. An approach considering a cohort of patients In several published papers patients reacting to placebo challenges are excluded from statistical analysis. This approach carries the risk of overestimating the actual frequency of patients with actual allergy. As a fictive example, the following outcome of a trial with 100 patients reacting with subjective symptoms only can be used for illustration: It is evident, that using the whole cohort, no correlation between challenge and outcome is obtained. Excluding the patients reacting to placebo (1 and 3), however, results in a frequency of 50% in the remaining patients. The frequency of placebo reactors in a trial must therefore always be taken into consideration and the actual frequency reported. In both cases, a statistical model has been developed (51). The use of such statistical evaluation of the outcome of a trial is highly recommended. All challenges should be documented. For comparative reasons, preformed and standardised documentation sheets should be used. Examples of such sheets are available at http://www.ig-food.org. The present position paper reviews the present level of knowledge for performing double-blind, placebo controlled challenges. The use of the guidelines presented here will both increase safety and feasibility for the patient and staff involved in the challenge procedure and also, by using mutual protocols, enable comparisons between results obtained in different centres.

Rationale To evaluate the clinical and economic consequences of treatment with High Dose Sublingual Immunotherapy (SLIT) in children and adolescents, in the perspective of the society and of the Italian National Healthcare Service. Methods The study involved one allergy center, located in the north of Milan (Italy). From the existing records of patients managed for allergic disease, we extracted all patients satisfying the following criteria: i) children and adolescents with allergic rhinitis and/or allergic asthma, ii) who had 1 year data prior to receiving SLIT; 3 year data on SLIT; at least 1 year follow-up data after discontinuation of SLIT. The following variables were recorded: outcome measures (number of asthma and rhinitis exacerbations, visits, absence from nursery or school); direct costs (euros spent on drug treatment, specialist visits, SLIT), indirect costs (costs resulting from children school and parental work loss). Results 135 patients satisfied the study entry criteria. Of these, 46 had perennial allergy, 89 had seasonal allergy. Gender distribution and age (mean 7.39 ± 3.6; 7.37 ± 3.62) were comparable in the sub-groups. A substantial reduction was seen in the number of exacerbations (mean 45 ± 12; 10 ± 4), specialist visits (9.9 ± 3.7; 2.2 ± 1.0) and school loss (38 ± 12; 2 ± 4) after SLIT as compared to the before period. For the whole group, the average actualized yearly cost per patient was _2463, _575, _145 respectively before, during, and after SLIT. Similar results were found for both perennial and seasonal allergy sub-groups. Conclusions High dose SLIT may be effective in reducing both the clinical and economic burden of allergic disease in children and adolescents.

SummaryBackground The allergological relevance of Ambrosia in Europe is growing but the efficacy of the injective immunotherapy for this allergen has been documented only in Northern America.Objective We sought to study the safety and efficacy of injective immunotherapy in European patients sensitized to Ambrosia artemisiifolia.Methods Thirty‐two patients (18 M/14 F, mean age 36.78, range 23–60 years) suffering from rhinoconjunctivitis and/or asthma and sensitized to Ambrosia were enrolled and randomized in a double‐blind, placebo‐controlled (DBPC) study lasting 1 year. A maintenance dose corresponding to 7.2 μg of Amb a 1 was administered at 4‐week intervals after the build‐up. During the second and the third year, all patients were under active therapy in an open fashion. Symptom and medication scores, skin reactivity to Ambrosia (parallel line biological assay), and pollen counts were assessed throughout the trial.Results Twenty‐three patients completed the trial. No severe adverse event was observed. During the DBPC phase, actively treated patients showed an improvement in asthmatic symptoms (P=0.02) and drug (P=0.0068) scores days with asthmatic symptoms (P=0.003), days with rhinitis symptoms (P=0.05), and days with intake of drugs (P=0.0058), as compared to before therapy. No improvement for any of these parameters was detected in the placebo group. Moreover, the number of days with rhinitis and asthma was significantly higher in the placebo as compared to the active group (P=0.048 and P<0.0001, respectively). Patients who switched from placebo to active therapy improved in rhinoconjunctivitis, asthma, and drug intake. The skin reactivity decreased significantly (12.2‐fold, P=0.0001) in the active group whereas a slight increase (1.07‐fold, P=0.87) was observed in the placebo group after the DBPC phase. After switching to active therapy, patients previously under placebo showed a significant decrease of this parameter (4.78‐fold, P=0.002).Conclusion Injective immunotherapy is safe and clinically effective in European patients sensitized to Ambrosia.

Background: Walnut is the most common cause of allergic reactions to tree nuts, as reported by large population studies. Two major allergens of walnut have been identified up until now: a 2S albumin and a vicilin-like protein.Objective: This study was designed to identify the walnut major allergens in the Italian population and to compare the walnut IgE-binding profile in patients with or without pollen allergy.Methods: We selected 46 patients either with oral allergy syndrome confirmed by open oral challenge or with systemic symptoms after ingestion of walnut. These patients' sera were used for the immunoblotting of walnut extract; the identified allergens were purified by HPLC and sequenced. A peach-walnut cross-inhibition study was then performed.Results: The only major allergen recognized by our study population was a 9-kd lipid transfer protein (LTP), recognized by 37 patients. Two other minor allergens of approximately 9-kd molecular weight, both belonging to the vicilin family, were recognized by 10 patients. IgE binding to walnut UP was completely inhibited by peach LTP.Conclusion: In Italian patients with walnut allergy confirmed by documented history of severe systemic reactions or by open oral food challenge, the major allergen is an LTP. The sensitization to this protein seems to be secondary to the sensitization to peach LTP, which acts as the primary sensitizer. LTP and vicilins were able to sensitize patients not allergic to pollen.

BACKGROUND:Few allergic reactions to grape are reported in the literature. In some cases an association with peach and cherry allergy was observed. No IgE-mediated reactions to wine have been described, and no grape major allergens have yet been identified.OBJECTIVE:We describe several severe reactions to grape or wine. We characterized the grape major allergens and tried to identify the allergen in wine.METHODS:We collected documented histories of allergic reactions to grape and wine. Grape allergens were identified by means of SDS-PAGE and immunoblotting and purified by means of HPLC. Using amino acid sequencing and mass spectrometry, we identified the family of proteins to which the allergens belong. Cross-reactivity with peach and cherry was evaluated by means of cross-wise inhibition experiments.RESULTS:Eleven patients with reactions to grape and 3 with anaphylactic reactions to wine were recruited. The major allergens were an endochitinase 4A and a lipid-transfer protein (LTP) that was homologous to and cross-reactive with peach LTP. A 24-kd protein homologous to the cherry thaumatin-like allergen was a minor allergen. Endochitinase 4A is very likely the allergen in vino novello and in vino Fragolino.CONCLUSIONS:Grape and wine might cause severe allergic reactions in sensitive patients. The major allergens of grape are endochitinase 4A, which is also the allergen of wine, and an LTP cross-reacting with the peach major allergen.

Background: In a previous study a 9-kd lipid-transfer protein (LTP) was identified as the major allergen of raw maize in a population of 22 anaphylactic patients. However, the stability of this protein in cooked maize is unknown.Objective: We investigated the allergenicity of 5 maize hybrids and its modification after different thermal treatments by using sera from anaphylactic patients and patients with positive double-blind, placebo-controlled food challenges.Methods: Five maize hybrids were extracted by using different methods, obtaining the water-soluble, zein, total zein, glutelin, and total protein fractions. The IgE-binding capacity of the different extracts, both raw and after thermal treatment, was investigated by means of SDS-PAGE immunoblotting. A 9-kd heat-stable allergen was purified by means of HPLC and sequenced. Changes in its secondary structure during and after heating from 25degreesC to 100degreesC were monitored by means of circular dichroism.Results: All raw maize hybrids showed similar protein and IgE-binding profiles. The SDS-PAGE of all the heat-treated hybrids demonstrated a decreased number of stained bands in respect to the raw samples. The IgE immunoblotting demonstrated that the major allergen of the water-soluble, total zein, total protein, and glutelin fractions was a 9-kd protein identified by means of amino acid sequence as an LTP and a subtilisin-chymotrypsin inhibitor (in total zein fraction). The IgE-binding capacity of this 9-kd protein remained unchanged after thermal treatments, even though circular dichroism demonstrated an altered secondary structure.Conclusions: Maize UP maintains its IgE-binding capacity after heat treatment, thus being the most eligible candidate for a causative role in severe anaphylactic reactions to both raw and cooked maize.

BACKGROUND:The hazelnut major allergens identified to date are an 18-kd protein homologous to Bet v 1 and a 14-kd allergen homologous to Bet v 2. No studies have reported hazelnut allergens recognized in patients with positive double-blind, placebo-controlled food challenge (DBPCFC) results or in patients allergic to hazelnut but not to birch.OBJECTIVE:We characterized the hazelnut allergens by studying the IgE reactivity of 65 patients with positive DBPCFC results and 7 patients with severe anaphylaxis to hazelnut.METHODS:Hazelnut allergens were identified by means of SDS-PAGE and IgE immunoblotting. Further characterization was done with amino acid sequencing, evaluation of the IgE-binding properties of raw and roasted hazelnut with enzyme allergosorbent test inhibition, assessment of cross-reactivity with different allergens by means of immunoblotting inhibition, and purification by means of HPLC.RESULTS:All the sera from the patients with positive DBPCFC results recognized an 18- and a 47-kd allergen; other major allergens were at molecular weights of 32 and 35 kd. Binding to the 18-kd band was inhibited by birch extract, indicating its homology with the birch major allergen, and abolished in roasted hazelnut. The 47-kd allergen is a sucrose-binding protein, the 35-kd allergen is a legumin, and the 32-kd allergen is a 2S albumin. Patients with severe anaphylactic reactions to hazelnut showed specific IgE reactivity to a 9-kd allergen, totally inhibited by purified peach lipid-transfer protein (LTP), which was heat stable and, when purified, corresponded to an LTP.CONCLUSIONS:The major allergen of hazelnut is an 18-kd protein homologous to Bet v 1, and the 9-kd allergen is presumably an LTP. Other major allergens have molecular weights of 47, 32, and 35 kd.

Background: Almond proteins can cause severe anaphylactic reactions in susceptible individuals. The aim of this study was the identification of IgE-binding proteins in almonds and the characterisation of these proteins by N-terminal sequencing. Methods: Five sera were selected from individuals with a positive reaction to food challenge. Sodium dodecylsulphate-polyacrylamide gel electrophoresis and immunoblotting were performed on almond seed proteins. Purified IgE-binding proteins were tested for immunoblot inhibition with sera pre-incubated with extracts of hazelnut and walnut. Results: N-terminal sequences of the 12-, 30- and 45-kD proteins were obtained. The 45- and 30-kD proteins shared the same N terminus, with 60% homology to the conglutin γ heavy chain from lupine seed (Lupinus albus) and to basic 7S globulin from soybean (Glycine max). The sequences of the N-terminal 12-kD protein and of an internal peptide obtained by endoproteinase digestion showed good homology to 2S albumin from English walnut (Jug r 1). Immunoblot inhibition experiments were performed and IgE binding to almond 2S albumin and conglutin γ was detected in the presence of cross-reacting walnut or hazelnut antigens. Conclusions: Two IgE-binding almond proteins were N-terminally sequenced and identified as almond 2S albumin and conglutin γ. Localisation and conservation of IgE binding in a 6-kD peptide obtained by endoproteinase digestion of 2S albumin was shown.

Adverse reactions to food may be toxic or non toxic, depending on the susceptibility to a certain food; non toxic reactions that involve immune mechanisms are termed allergy if they are IgE‐mediated. If no immunological mechanism is responsible, it is termed intolerance. The following disorders are considered a consequence of food allergy: gastrointestinal reactions (oral allergy syndrome, vomiting, diarrhea, protein‐induced enterocolitic syndrome, eosinophilic gastroenteritis); respiratory reactions (rhinitis, asthma, laryngeal edema); cutaneous reactions (urticaria‐angioedema, atopic dermatitis); anaphylaxis. There is much recent evidence to consider celiac disease an immunological disorder. Food allergy diagnosis is based on history, SPT, specific IgE, food challenges. DBPCFC is fundamental for diagnosing true food allergy; patients who have had anaphylaxis to food must not undergo DBPCFC. Rapidly progressive respiratory reactions and anaphylactic shock are life‐threatening reactions that can be caused by food allergy. The doses of food inducing anaphylaxis can be very low, therefore commercial cross‐contamination with an unsuspected food during food processing can be risky for the food allergic patient. The prevention of severe anaphylactic food reactions may lie in interdisciplinary collaboration among allergologists, chemists, food technologists, and experts in food industry research.