Quality Standards for Allergen Immunotherapy Clinics in Spain: Consensus Document

BACKGROUND AND OBJECTIVE

Allergen immunotherapy clinics (AITCs) in Spain differ widely in terms of structure, organization, resources, and portfolio of services. Therefore, it is essential to unify treatment criteria and define quality standards for the most complex AITCs. Objective: To establish a series of recommendations that make it possible to guarantee quality and safety in the administration of immunotherapy and define quality standards for the most complex AITCs.

METHODS

This project began with an online survey of 65 allergy departments/units throughout Spain in 2013. Next, a 2-phase consensus process was carried out. In the first phase, 10 experts defined and agreed on the standards using the RAND/UCLA Appropriateness method; in the second, the agreements were validated by means of a 2-round Delphi consultation with 84 experts.

RESULTS

Consensus was reached on minimum safety and quality criteria in the administration of allergen immunotherapy, and 2 levels of highly complex AITCs were defined: accredited AITCs and accredited AITCs with excellence. Consensus was also reached on quality standards and accreditation criteria for both levels.

CONCLUSIONS

This project is pioneering in terms of its purpose (the definition of quality standards for AITCs) and of the use of structured participation techniques (combination of the RAND/UCLA and Delphi methods). It enabled the design of minimum standards for quality and safety in administering AIT, as well as quality criteria for accreditation of AITCs supported by a broad panel of experts from the Spanish Society of Allergology and Clinical Immunology.

Specific allergen immunotherapy for the treatment of allergic asthma: a review of current evidence

Asthma is frequently associated with atopy, characterized by the production of specific immunoglobulin E in response to environmental allergens. Currently, two types of allergen immunotherapy (AIT) are used in clinical practice: subcutaneous and sublingual immunotherapy, both accepted as key components of the therapeutic repertoire for allergic rhinitis and conjunctivitis. However, their role in asthma remains controversial. The present document is aimed at providing the clinicians with a review of the evidence on the use of AIT in asthma, focusing on the most relevant aspects of its mechanism of action, its efficacy, and existing data on safety, tolerability, and cost-effectivity, both in pediatric and adult populations. A systematic search of MEDLINE, Cochrane, and Clinical Trials databases from 2000 to April of 2016 was carried out by a panel of experts from the Spanish Allergy and Clinical Immunology Scientific Society. Relevant studies prior to the year 2000 included in ulterior systematic reviews were also considered. More than 4000 articles were identified during the search and 241 were selected to retrieve available evidence on AIT, which was graded according to the Oxford classification. All the group members reviewed the resulting text until the final version reached the consensual agreement. A summary of recommendations on the more relevant topics are proposed. The role of AIT as a valuable therapeutic strategy for prevention of exacerbation and progressive decline in lung function is highlighted. Future research should include specific tools for asthma evaluation when assessing AIT effectiveness in asthmatic patients.

European Survey on Adverse Systemic Reactions in Allergen Immunotherapy (EASSI): a real-life clinical assessment

BACKGROUND

Outside clinical trials, data on systemic reactions (SRs) due to allergen immunotherapy (AIT) are scarce.

METHODS

A prospective, longitudinal, web-based survey of 'real-life' respiratory allergen immunotherapy (AIT) clinical practice was conducted in France, Germany and Spain. SRs were recorded and coded according to the Medical Dictionary for Regulatory Activities (MedDRA) and risk factors associated with SRs were identified.

RESULTS

A total of 4316 patients (corresponding to 4363 ongoing courses of AIT) were included. A total of 109 SRs were recorded, and 90 patients (2.1%) presented at least one SR. Most of the SRs occurred in subcutaneous allergen immunotherapy (SCIT) (89%, n = 97). The most frequently reported symptoms were urticaria, rhinitis, dyspnoea and cough. Respiratory symptoms appeared before skin symptoms. Most SRs occurred during the up-dosing phase (75.8%) and were mild in severity (71.6%). Intramuscular adrenaline was administered in 17 SRs, but only 65% of these were subsequently classified as anaphylaxis. Independent risk factors for SRs during SCIT were as follows: the use of natural extracts (odds ratio, OR) [95% confidence interval (CI)] = 2.74 [1.61-4.87], P = 0.001), the absence of symptomatic allergy medications (1.707 [1.008-2.892], P = 0.047), asthma diagnosis (1.74 [1.05-2.88], P = 0.03), sensitization to animal dander (1.93 [1.21-3.09], P = 0.006) or pollen (1.16 [1.03-1.30], P = 0.012) and cluster regimens (vs rush) (4.18 [1.21-14.37], P = 0.023). A previous episode of anaphylaxis increased the risk for anaphylaxis in SCIT (OR [95% CI] = 17.35 [1.91-157.28], P = 0.01).

CONCLUSION

AIT for respiratory allergy is safe, with a low number of SRs observed in real-life clinical practice. A personalized analysis of risk factors could be used to minimize SRs.

Evidence in immunotherapy for paediatric respiratory allergy: Advances and recommendations

Allergic respiratory diseases are major health problems in paediatric population due their high level of prevalence and chronicity, and to their relevance in the costs and quality of life. One of the most important risk factors for the development of airway diseases in children and adolescents is atopy. The mainstays for the treatment of these diseases are avoiding allergens, controlling symptoms, and preventing them through sustained desensitization by allergen immunotherapy (AIT). AIT is a treatment option that consists in the administration of increasing amounts of allergens to modify the biological response to them, inducing long-term tolerance even after treatment has ended. This treatment approach has shown to decrease symptoms and improve quality of life, becoming cost effective for a large number of patients. In addition, it is considered the only treatment that can influence the natural course of the disease by targeting the cause of the allergic inflammatory response. The aim of this publication is to reflect the advances of AIT in the diagnosis and treatment of allergic respiratory diseases in children and adolescents reviewing articles published since 2000, establishing evidence categories to support the strength of the recommendations based on evidence. The first part of the article covers the prerequisite issues to understand how AIT is effective, such as the correct etiologic and clinical diagnosis of allergic respiratory diseases. Following this, the article outlines the advancements in understanding the mechanisms by which AIT achieve immune tolerance to allergens. Administration routes, treatment regimens, dose and duration, efficacy, safety, and factors associated with adherence are also reviewed. Finally, the article reviews future advances in the research of AIT.

Eosinophilic Enteritis Due to Anisakis: A Call for Pathologists' Attention

Anisakis simplex, a common parasite of the fish we eat, can cause eosinophilic enteriis by direct parasitization. The authors describe six cases of intestinal anisakiasis dignosed by morphologic and immunologic studies in vivo and in vitro, five being retospective cases of unclassified eosinophilic enteritis. All patients presented with symptoms of acute abdomen requiring urgent surgery. They all had segmental lesions in the jejunum and/or ileum. Histologically the authors observed eosinophilic miroabscesses; in two cases Anisakis larvae were found. None of the patients declared having eaten raw fish. The surgical pathologist plays a basic role in detecting this disase, although additional serologic investigation of anti-Anisakis IgE and a skin test should be done whenever possible.

Variation in allergen content in sublingual allergen immunotherapy with house dust mites

Background

Allergen immunotherapy is a treatment modality which can be applied using different vaccines. The aim of this study was to quantify and compare the allergen content of different house dust mites (HDM)’ sublingual treatments and to review the evidence on their efficacy.

Methods

Five sublingual allergen immunotherapy (SLIT) products were ordered and purchased at an ordinary pharmacy and masked for blinding before the study was started. Detection of Dermatophagoides pteronyssinus and Dermatophagoides farinae allergens Der p 1, Der f 1, Der p 2 and Der f 2 was carried out by immunoblotting and fluorescent multiplex. A literature search for meta‐analyses and systematic reviews that included SLIT‐HDM products was performed.

Results

Der p 1 concentrations ranged from 0.6 to 14.5 μg/ml; similar figures were found for Der f 1 that ranged from 0.2 to 12.4 μg/ml. Der p 2+ Der f 2 ranged from 0.2 to 1.5 μg/ml. Data on efficacy are scarce for most of the five products.

Conclusions

Substantial variations regarding allergen content were found among these five SLIT‐HDM products. Therefore, it can be necessary to guarantee the quality of the SLIT‐HDM products and to demonstrate their effectiveness before they are marketed. It seems necessary, for the moment, to take into account these characteristics of the products before prescribing.

Phase II/III clinical trial to assess the tolerability and immunological effect of a new updosing phase of Dermatophagoides mix-based immunotherapy

BACKGROUND

Immunologically enhanced subcutaneous specific immunotherapy (SCIT) has been developed with a fast and simplified updosing phase containing equal parts of the house dust mites (HDM) Dermatophagoides pteronyssinus and Dermatophagoides farinae (Dermatophagoides mix) adsorbed on aluminum hydroxide.

OBJECTIVE

To evaluate the tolerability and immunological impact of the updosing phase of this new allergen extract formulation.

MATERIAL AND METHODS

We performed a multicenter, open-label, single-arm, phase II/III clinical trial. The inclusion criteria were a clinical history of rhinitis/conjunctivitis due to HDM (with/without asthma) and sensitization to HDM (positive specific IgE and skin prick test). Five updosing injections of Dermatophagoides mix (300, 600, 3000, 6000, and 15000 SQ+) were administered at weekly intervals with 1 maintenance injection (15000 SQ+) 2 weeks after the last updosing injection. Two days after each visit, patients were contacted by telephone to follow up on any adverse events. IgE-blocking factor, IgG4, and immediate skin reactivity were evaluated.

RESULTS

The sample comprised 102 patients (mean [SD] age, 29.3 [7.7] years; male, 52.9%). There were 117 adverse drug reactions (ADR): 101 were local, regardless of reaction size, in 48 (47.1%) patients and 7 were systemic (all grade I) in 5 (4.9%) patients. All ADRs were mild, except for 1, which was moderate. Six weeks of treatment led to statistically significant increases in IgE-blocking factor and IgG4, as well as a significant reduction in immediate skin reactivity.

CONCLUSION

This new updosing phase of Dermatophagoides mix-based immunotherapy had a good tolerability profile and induced a significant immunological effect.

Are basophil activation and sulphidoleukotriene determination useful tests for monitoring patients with peach allergy receiving sublingual immunotherapy with a Pru p 3-enriched peach extract?

INTRODUCTION

Treatment of food allergy essentially consists of food avoidance, but immunotherapy with food is emerging as a new therapeutic option.

OBJECTIVE

To evaluate clinical improvement and immunological changes in patients with peach allergy following sublingual immunotherapy (SLIT) with a Prup3 quantified peach extract.

METHODS

A randomized, double-blind, placebo-controlled clinical trial with peach SLIT was conducted. We assessed clinical efficacy after 6 months of treatment by means of double-blind, placebo-controlled oral challenges with peach and also evaluated immunological changes (basophil activation test [BAT] and determination of sulphidoleukotriene production) following stimulation with peach peel and pulp, rPrup3, rMald 1, and rMal d 4 stimulation. We also measured specific IgE and IgG4 to Pru p3.

RESULTS

After 6 months of SLIT (T6), the active group showed a 3-fold improvement in tolerance to Prup3 and a significant increase in IgE to rPrup3 and in sLT production following stimulation with peach peel and rPrup3. There was also a significant increase in BAT results after stimulation with rPrup3 at 1 month of SLIT (T1). Statistically significant between-group differences were only observed for BAT with peach peel and pulp at T1 and T6 and for BAT with rPru p3 at T6. No changes were observed in BAT with rMal d 1 or rMal d 4 or in IgG4 levels to nPrup3.

CONCLUSIONS

SLIT with a Pru p 3 quantified peach extract is clinically effective and leads to an increase in basophil activation and sulphidoleukotriene production following stimulation with rPru p3 and peach peel in the first months of treatment.

Allergen-specific immunotherapy: update on immunological mechanisms

Immunotherapy selectively modulates the allergen-specific immune response. It involves the gradual administration of increasing amounts of allergen for the purpose of inducing protective immunological changes and it is the only curative approach for specific type I allergy.

AIM

Description of the allergic inflammation.- Comprehension of the early cellular changes after specific immunotherapy has been initiated. Exposure of the mechanisms involved in tolerance induction by regulatory T cells (Treg) with the inhibition of the Th2 responses. Comprehension of IL-10 and transforming growth factor (TGF- ) roles. Explanation of specific IgE, IgG and IgA changes. Description of the suppression of inflammatory responses during immunotherapy.

Analysis of mite allergic patients in a diverse territory by improved diagnostic tools

BACKGROUND

There are few studies comparing the sensitization with mite allergens from different mite species which could potentially be the cause of allergy.

OBJECTIVE

To improve the diagnosis of mite allergic patients from a diverse territory in which D. pteronyssinus/D. farinae mites together with storage mites could be present in the environment.

METHODS

Four hundred and seventy-seven patients (both children and adults) from different regions, covering the main mite prevalent areas of Spain, were recruited. sIgE to eight allergens was measured together with SPT to whole mite extracts, level of mite allergen exposure, and specific IgG(4) . BAT and CAST was performed in a subgroup of patients.

RESULTS

D. pteronyssinus and L. destructor were more prevalent in Atlantic areas, whereas D. farinae predominate in Mediterranean areas. About 90% of patients were sensitized to group 1 and/or group 2 allergens. Group 2 was the most prevalent, and the IgE response/intensity of sensitization in BAT was higher. sIgE to Der p 2/Der f 2 was almost fully cross-reactive, but no cross-reactivity was detected with Lep d 2. Group 1 allergens were also cross-reactive, but in some patients a species-specific response was observed. sIgE to Lep d 2 was associated with SPT results to storage mites. Sensitization to Der p 1 was more frequent in children, whereas Lep d 2 sensitization was more frequent in adults. A higher ratio IgE/IgG(4) to Der p 2 was associated with the presence of allergic asthma.

CONCLUSION

An improved diagnosis algorithm has been established. Group 2 allergens seem to have a leading role in mite allergy, but as group 1 sensitization could be species-specific in some patients and its prevalence is higher in children, an adequate balance on major mite species and major allergens must be consider in the design of mite allergy vaccines.

An epidemiological survey of hymenoptera venom allergy in the Spanish paediatric population

Hypersensitivity reactions to hymenoptera venom are infrequent in paediatric patients. A study was made to determine the incidence of this pathology in children, based on an epidemiological survey targeted to all members of the SEICAP (Sociedad Española de Inmunología Clínica y Alergia Pediátrica/Spanish Society of Paediatric Clinical Immunology and Allergy), and designed to collect the data on patients under 17 years of age diagnosed with hymenoptera venom allergy.

RESULTS

The data corresponding to 175 patients (135 males) were collected. The mean age was 9.9 ± 3.6 years. Seventeen percent (32 patients) were the offspring of beekeepers, and 68.9% had experienced previous stings. The causal insect was Apis melifera, implicated in 55 cases, followed by Polistes dominulus (33 cases). In 151 patients (83.9%) the condition consisted of a local reaction. The most frequent systemic response was urticaria and angio-oedema. Fourteen patients suffered anaphylactic shock. The diagnosis was based on skin test (intradermal and prick) and/or specific IgE testing. Three treatment categories were established: (a) prevention and educational measures; (b) symptomatic treatment with oral antihistamines as well as self-injectable adrenalin; and (c) immunotherapy. In this context, 135 patients underwent immunotherapy with a mean duration of 3.5 ± 1.7 years (range 2-5 years) - with excellent tolerance. The starting regimen was predominantly conventional (92 patients).

CONCLUSIONS

The results of this survey show hypersensitivity reactions to hymenoptera venom to be infrequent in paediatrics, though with a strong impact upon patient quality of life.

Sublingual immunotherapy in peach allergy: monitoring molecular sensitizations and reactivity to apple fruit and Platanus pollen

BACKGROUND

Peach allergy is prevalent, persistent, and potentially severe and as such is a target for immunotherapy. Our aims were to evaluate the profile of sensitization to Rosaceae allergens and the effects of sublingual peach immunotherapy on immunoglobulin (Ig) E levels to these allergens, to monitor for neosensitizations, and to check if this treatment modified other Rosaceae fruit and pollen-related sensitizations.

METHODS

A double-blind placebo-controlled trial was conducted on 56 peach-allergic patients who received, sublingually, a standardized peach extract quantified in mass units of Pru p 3, or placebo for 6 months. IgE to recombinant (r) Mal d 1, rMal d 4, rPru p 3, and natural (n) Art v 3 and skin prick test (SPT) reactivity to Platanus pollen and apple extracts evaluated before treatment (T0), after 1 month (T1) and after and 6 months (T6) were recorded.

RESULTS

In total, 18.5% of patients recognized rMal d 1, 83.3%, rPru p 3, 24.1%, rMal d 4, and 25.9% nArt v 3. IgE to Pru p 3 rose from T0 to T1 in both the active group (P = .003) and the placebo group (P = .022), and remained elevated at T6 in the active group (P = .001). IgE to other purified allergens did not change significantly and no relevant neosensitizations were detected. SPT reactions to peach decreased from T0 to T6 in the active group (P < 0.05). Reactivity to peach (T1 and T6) and apple (T6) was lower in the active group than in the control group.

CONCLUSIONS

The main allergen was Pru p 3. Changes in rPru p 3 IgE levels and in peach and apple extract SPT were induced by sublingual immunotherapy.

Component-resolved diagnosis of pollen allergy based on skin testing with profilin, polcalcin and lipid transfer protein pan-allergens

BACKGROUND

Allergy diagnosis needs to be improved in patients suffering from pollen polysensitization due to the existence of possible confounding factors in this type of patients.

OBJECTIVE

To evaluate new diagnostic strategies by comparing skin responses to pan-allergens and conventional allergenic extracts with specific IgE (sIgE) to purified allergen molecules.

METHODS

One thousand three hundred and twenty-nine pollen-allergic patients were diagnosed by a combination of an in vitro method with a panel of 13 purified allergens, including major allergens and pan-allergens, using a high-capacity screening technology (ADVIA-Centaur) and skin prick test (SPT) to pan-allergens and conventional extracts.

RESULTS

There was a high concordance (kappa index) between in vitro (sIgE to major allergens) and in vivo (SPT to conventional extracts) methods in patients who were not sensitized to pan-allergens, but SPT with conventional extracts failed to diagnose patients with sensitization to pan-allergens. In patients who were simultaneously sensitized to polcalcins and profilins, there was a duplication both in the number of sensitizations to major allergens and in the years of disease evolution. There was a statistical association between sensitization to profilins and/or lipid transfer proteins and food allergy (P<0.0001).

CONCLUSION

The novel diagnostic strategy has proven to be a valuable tool in daily clinical practice. Introduction of routine SPT to pan-allergens is a simple and feasible way of improving diagnostic efficacy. Patients sensitized to pan-allergens should be tested by an adequate panel of allergenic molecules in order to identify the allergens that are responsible for the allergic disease.

Randomized double-blind, placebo-controlled trial of sublingual immunotherapy with a Pru p 3 quantified peach extract

BACKGROUND

Peach allergy is highly prevalent in the Mediterranean area; it is persistent and potentially severe, and therefore a prime target for immunotherapy. We aimed to study the efficacy and safety of sublingual immunotherapy (SLIT) with a peach extract quantified in mass units for Pru p 3, the peach lipid transfer protein.

METHODS

Randomized, double-blind, placebo-controlled (DBPC) clinical trial. The main efficacy outcome was the change in the response to a DBPC food challenge (DBPCFC) with peach. Secondary efficacy outcomes were the changes in skin prick test (SPT), and in specific immunoglobulin E (IgE) and IgG(4) to Pru p 3. Tolerance was assessed with a careful recording of adverse events.

RESULTS

After 6 months of SLIT, the active group tolerated a significantly higher amount of peach (three- to ninefold), presented a significant decrease (5.3 times) in SPT, and a significant increase in IgE and IgG(4) to Pru p 3. No significant changes were observed within the placebo group. Statistically significant inter-group differences were only observed in the SPT and IgG(4) responses. No serious adverse events were reported. Systemic reactions were mild, and observed with a similar frequency in both groups. Local reactions were significantly more frequent in the active group (three times) and 95% of them restricted to the oral cavity.

CONCLUSION

In this first exploratory clinical trial, SLIT for peach allergy seems to be a promising therapeutic option that could modify the clinical reactivity of the patients to peach intake and the underlying immunological response with a good tolerance.

Oral lyophilisate and food immunotherapy: from research to clinical practice

Thanks to its excellent safety profile, sublingual immunotherapy has served as a basis for launching two important lines of research in current allergology: sublingual immunotherapy with pharmaceutical registry (oral lyophilizates or tablets), and sublingual immunotherapy with food. At present, clinical trials are being conducted which use rapid dissolution oral lyophilizates. The results of the clinical trials carried out in large patient groups and based on a double-blind methodological design have allowed pharmaceutical registry of this form of treatment, with the therapeutic indications of rhinitis and allergy to grasses. Phleum lyophilizate indicated for the treatment of rhinoconjunctivitis will be marketed in Spain in the coming months. In parallel to development of the sublingual route, advances in our knowledge of pollen allergy and its relationship to plant food allergies have facilitated the conducting of studies involving sublingual immunotherapy for allergy to kiwifruit, hazelnut and peach - thus giving rise to promising future perspectives for affected patients.

Tatuaje de henna en niños: ¿natural y temporal?

BACKGROUND

Tattoos of natural red/brown henna obtained from the indigenous tree Lawsonnia have been traditionally performed with a few side-effects. Nowadays black henna tattoos are usually performed even in children. The addition of several chemical agents to improve its cosmetic properties has increased the risk of developing contact dermatitis after exposure. Our aim is to determine the causative agents of contact dermatitis in two children wearing henna tattoos.

MATERIAL AND METHODS

Case 1: A 12-year-old girl with no atopy presented local vesicles 10 hours after a black henna tattoo was applied. She had presented similar symptoms with a previous tattoo. Case 2: A 7-year-old atopic boy presented vesicles 2 weeks after a black henna tattoo was applied. He had dyed his hair previously without side effects. Both patients cured, after 3-4 weeks of treatment with topic corticosteroids, with residual hypo-pigmentation. Skin prick test with natural and commercial henna and epicutaneous test with TRUE-TEST, PABA derivatives compounds tests, textile dyes and natural and commercial henna were performed.

RESULTS

The epicutaneous tests were positive for p-Metilaminophenol, p-Aminobencene, p-Phenilendiamine and p-Toluenodiamine in both patients. The first patient had also positive tests for Benzocaine, Hydroquinone, Isobutyl p-aminobenzoate, Yellow 1 and Orange 1 disperse; the second one for Red 1 and Orange 1 disperse. In both cases the prick and epicutaneous tests for henna were negative.

CONCLUSIONS

Two children presented contact dermatitis after black henna tattoo due to added additives such as paraphenilendiamine.

Once daily sublingual immunotherapy without updosing--A new treatment schedule

BACKGROUND

Treatment regimens with specific immunotherapy include updosing. Due to excellent tolerance of sublingual immunotherapy (SLIT), it was hypothesized that administration of once-daily SLIT could be initiated safely without updosing. The objective was to evaluate tolerability of SLIT administered once daily without updosing.

METHODS

135 patients suffering from allergic rhinitis with/without asthma were included in a double-blind, placebo-controlled, parallel-group study. Patients were randomized into two groups. Group 1 (n = 69) received active treatment throughout the study, including 10 days updosing (T1), 20 days maintenance treatment (T2), and 2 consecutive months on maintenance treatment (T3 and T4). Group 2 (n = 66) obtained placebo updosing (T1), placebo maintenance (T2), initiated active treatment (maintenance) at T3, and continued active treatment until the end of the study (T4). Adverse events (AEs) were assessed at T1-T4. 66 grass- and 69 mite-allergic patients were evenly distributed between groups.

RESULTS

229 AEs were reported, 157 AEs were related to treatment. The most frequently reported AEs (>5% of patients in any group) related to treatment were oral itching, ocular itching, rhinitis, and sublingual edema. For group 1 at T2, the rate of all AEs related to treatment per dose administered was 1.79%, and for group 2 at T3 the rate was 1.33% (p = 0.37). For the most frequently reported AE, oral itching, the rate per dose administered was 1.01% for group 1 at T2, and 0.74% for group 2 at T3 (p = 0.53).

CONCLUSIONS

Once daily SLIT was well tolerated and can be safely initiated without updosing.

Biological standardization and maximum tolerated dose estimation of an Alternaria alternata allergenic extract

BACKGROUND

The manufacture of allergenic extracts from the mold Alternaria alternata is influenced by factors such as strain variability, allergenic origin, culturing conditions and extraction process, which affect the reproducibility of the preparations intended for diagnostic and therapeutic use.

OBJECTIVES

To select the most adequate antigenic source of A. alternata extracts and determine its maximum tolerated dose (MTD) to be used in a subsequent immunotherapy efficacy clinical trial.

METHODS

Twenty-one patients monosensitized to A. alternata were involved in a biological standardization process of A. alternata extracts. Four different mold strains were cultured and used to produce extracts by three different methods, each incorporating proteins from different origins: culture filtrate, buffer extractable fraction and cellular antigens. The selected extract, characterized as in-house reference (IHR) preparation was used in a MTD finding immunotherapy study. Serum IgE, IgG, IgG1 and IgG4 specific of complete extract and purified natural and recombinant forms of Alt a 1 were determined by different EIA methods.

RESULTS

Culture filtrate extract containing the allergens secreted to the spent medium was shown to be the most adequate option for establishing an IHR preparation for A. alternata extract manufacturing. A maximum dose of 1670 UBE, equivalent to 0.1 microg Alt a 1, was determined as MTD for immunotherapy. One year of administration of such a dose at monthly intervals elicited pronounced immunological changes with statistically significant decreases in IgE and increases in IgG4, both estimated with whole extract or purified Alt a 1.

CONCLUSION

A high quality natural A. alternata extract has been developed and preliminarily tested to define its MTD for subsequent determination of the optimal dose in an immunotherapy efficacy clinical trial.

Evaluation of paediatric tolerance to an extract of Alternaria alternata under two treatment regimes. A multicentre study

In order to evaluate the efficacy and safety of an extract of Alternaria alternata in a paediatric population, a two phase study plan has been elaborated that in the first place consists of a retrospective analysis of tolerance under the standard treatment regimes used by the clinical groups involved. This was achieved by analysing the records of 94 patients that have been treated with this extract, these being consecutive patients included at 7 clinics over a period of 6 months. Two regimes were used: a conventional short regime of 7 doses and a cluster regime. Under neither of these two regimes were any serious reactions registered. The percentage of local reactions was significantly greater using the short conventional regime than with the cluster regime (1.9% and 0.4% respectively, p = .035). In contrast, no significant differences were observed with respect to the systemic reactions (0.5% and 1.2%), these percentages also being similar to those registered with other extracts in which identical regimes have been used. In conclusion, we can confirm that a very satisfactory tolerance profile was observed, with the advantage that through using shorter regimes than the conventional regime of 13 doses, a considerable saving is made both in the number of visits and the doses necessary to reach the maintenance dose.

Comparative analysis of the bronchodilator response measured by impulse oscillometry (IOS), spirometry and body plethysmography in asthmatic children

BACKGROUND

Asthma is common among young children. The assessment of respiratory resistance by the impulse oscillometry system (IOS), based on the superimposition of respiratory flow by short-time impulses, requires no patient active collaboration.

AIM

We evaluated the baseline repeatability and bronchodilator response of IOS indices in preschool children, their correlation with spirometry and whole body plethysmography, and differences between atopic and nonatopic children.

PATIENTS AND METHODS

Thirty-three asthmatic children (3-6 yrs.) underwent IOS measurement (R5rs, R20rs and X5rs) by triplicate at the baseline, after placebo and after salbutamol inhalation. Spirometry (FEV1) and whole body plethysmography (sRaw) were made at the baseline and after salbutamol. Baseline within-test (coefficient of variation: CV%) and between-test repeatability (baseline-placebo) were addressed. Bronchodilator response was evaluated by the SD index (change in multiples of the between-test repeatability).

RESULTS

Baseline repeatability for R5rs was 4.1%. Its values decreased by 2SD after salbutamol inhalation, and correlated with FEV1 and sRaw at both, baseline (r=-0.51 and r=0.49) and post-salbutamol (r=-0.63 and r=0.54). A trend towards correlation between salbutamol-induced changes in R5rs and in sRaw (r=0.33) was observed. Atopic and non-atopic children showed no differences in lung function.

CONCLUSION

IOS was well accepted by young asthmatic children and provided reproducible and sensitive indices of lung function. Resistance values obtained by IOS at low frequency (R5rs) were reproducible and correlated with spirometry and plethysmographic values.

Respiratory allergy to peach leaves and lipid-transfer proteins

BACKGROUND

Several lipid-transfer proteins (LTPs) have been identified as important food allergens, especially in fruits of the Rosaceae family. The major peach (Prunus persica) allergen has been identified, sequenced and designated Pru p 3.

OBJECTIVE

To present Pru p 3 as an aeroallergen able to induce occupational asthma.

METHODS

A thorough investigation was performed in a fruit grower with occupational asthma. Skin prick-prick tests with peach leaves and prick tests with perennial respiratory allergens and pollens, fruits and peach leaf extracts were done. Serum-specific IgE was tested for peach leaf, peach fruit, peach skin and respiratory allergens that were positive in skin prick tests. Specific bronchial provocation tests (BPTs) with extracts of peach leaf were also done. Before and 24 h after the BPT, BPTs with methacholine and sputum induction were done. The IgE reactivity pattern to peach leaf and fruit extracts and to Pru p 3 was identified by using SDS-PAGE and immunoblotting. Blotting inhibition of peach leaf extract by Pru p 3 was also performed. The putative allergen was quantified in leaf and fruit skin extracts with ELISA based on an anti-Pru p 3 antibody.

RESULTS

Skin tests were positive for peach leaf and fruit. The BPT was positive, with immediate and delayed response. This test induced a decrease in PD20 (dose of agonist that induces a 20% fall in FEV1) methacholine and an increase in eosinophils and eosinophil cationic protein in sputum. Peach leaf extract contained concentrations of Pru p 3 similar to those found in peach skin. Specific IgE immunodetection showed that patient's sera reacted with Pru p 3, and with a single major band from the peach leaf extract fully inhibited by Pru p 3.

CONCLUSION

Pru p 3 from peach leaves can act as a respiratory allergen and cause occupational rhinoconjunctivitis and asthma.

Diversity of asparagus allergy: clinical and immunological features

BACKGROUND

Asparagus (Asparagus officinalis) is an extensively grown and consumed vegetable. To a lesser extent than other Liliaceae vegetables, allergic contact dermatitis (ACD) due to asparagus has been reported. However, only a few case reports of asparagus IgE-mediated allergy have been published. In a previous study, we demonstrated that two lipid transfer proteins (LTPs) (Aspa o 1.01 and Aspa o 1.02) were relevant allergens of asparagus.

OBJECTIVE

We retrospectively analysed the 27 patients diagnosed with asparagus allergy during the last 5 years. All of them reported adverse symptoms after either asparagus ingestion or handling. We describe their clinical features and evaluate whether they were associated to immunological findings (immunoblot pattern and skin reactivity to LTPs).

METHODS

Patients underwent skin prick and patch tests with standard panels of vegetables and aeroallergens. Besides crude asparagus extract, two purified LTPs were prick and patch tested. Total and specific IgE measurements and asparagus extract IgE immunoblotting were performed. Patients reporting asthma symptoms underwent specific inhalation challenge to asparagus.

RESULTS

Of the 27 subjects, eight had ACD, 17 had IgE-mediated allergy and two had both ACD- and IgE-mediated allergy. Positive patch tests with the crude asparagus extract but not with LTPs were observed in subjects with ACD (n=10). Of 19 patients with IgE-mediated disease, 10 had contact urticaria after asparagus handling. Of them, five subjects and five others without skin allergy showed respiratory symptoms; of them, eight were diagnosed with occupational asthma confirmed by positive asparagus inhalation challenge, whereas the remaining two had isolated rhinitis. Four patients suffered from immediate allergic reactions related to asparagus ingestion (food allergy); three of them reported anaphylaxis whereas the other had oral allergic syndrome. Positive IgE immunoblotting (bands of 15 and 45-70 kDa) was observed in 10 subjects. Of 10 subjects with positive prick test to LTPs, six showed bands at 15 kDa. Either IgE-binding bands or positive prick tests to LTPs were observed in asthma (62%) and anaphylaxis (67%).

CONCLUSION

Asparagus is a relevant source of occupational allergy inducing ACD and also IgE-mediated reactions. Severe disease (anaphylaxis or asthma) is common and LTPs seem to play a major role. The clinical relevance of LTP sensitization among patients with mild disease or symptom-free subjects should be addressed in prospective studies.

Olerance of a cluster schedule with a house dust mite extract quantified in mass units: multicentre study

The standardisation of allergenic extracts in micrograms of the major allergen has encouraged the search for new treatment schedules, with the purpose of shortening the number of visits and doses required to reach the maintenance dose without eliciting a greater risk of adverse reactions for the patients. With this objective, a prospective multicentre pharmacovigilance study was designed that included 200 patient with allergic rhinoconjunctivitis and/or allergic asthma sensitised to mites (Dermatophagoides pteronyssinu and/or farinae). The dose increment period was carried out using a cluster schedule, where the optimal dose wa reached after 4 visits, administering two doses in each visit. The duration of the study was 5 months and a total o 1902 doses were administered. At the end of the trial, 31 adverse reactions in 23 patients were recorded. Six of these were systemic (0.3% of t administered doses) recorded in 6 patients (3% of the sample). One was an immediate reaction (grade 1) and delayed (4 mild and 1 moderate). Two were asthmatic exacerbations, 2 cutaneous reactions, 1 rhinitis and 1 an unspecific symptom (not IgE-mediated). Two appeared upon administration of the first vial and the remaining 4 after administration of the third cluster. Therefore, the schedule tested presents an adequate tolerance profile, suggesting savings (compared to th conventional schedule of 13 doses per patient) of 1800 visits and 1000 treatment doses in the whole study.

[Atopic dermatitis in paediatric practice]

Atopic dermatitis is the most frequent dermatitis amongst children under 11 years of age. It is an inflammatory cutaneous disease, chronic and recurrent, and it involves numerous outbreaks and relapses that affect the child, and hence his family milieu, generally for several years. Its chronic character and the lack of fully satisfactory therapies force the primary care paediatrician to consider this entity as a factor conditioning the quality of life of the patients and as a warning sign for the possible development of other allergic processes. As we do not have a curative treatment available, special relevance is assumed by family collaboration, by the measures for preventing relapses and by efficacy in their symptomatic treatment.

[Sublingual immunotherapy in children. Immunotherapy Committee of the Spanish Society for Clinical Immunology and Pediatric Allergology]

Sublingual immunotherapy is currently attracting growing interest because of its ease of administration and, according to previous studies, its infrequent and mild adverse effects. However, at least in children, the efficacy of this therapy has not been completely demonstrated. In addition, the mechanisms of action remain to be elucidated since few studies have been published and the results have been contradictory and sometimes inconclusive. For this reason, we performed a literature review through the MEDLINE database, selecting double-blind studies carried out in children. Only 10 studies meeting these requirements were retrieved. All the studies were performed by European researchers and nine were published in European journals. Efficacy was evaluated by clinical parameters and by reduction in medication use. The results on efficacy are not homogeneous, although most support the utility of this route of administration. Moreover, reports of allergens other than those used in these studies dust mites and grass pollens are lacking. In conclusion, further studies evaluating the efficacy of this therapy in children are required. Among the general population, if the efficacy of sublingual immunotherapy in the treatment of sensitization to hymenoptera venoms were demonstrated, as has been the case with subcutaneous immunotherapy, the utility of this route of administration would be definitively confirmed. Finally, sublingual immunotherapy could be used in children who have shown systemic reactions to subcutaneous immunotherapy or who refuse to undergo injections.

[Local immunotherapy]

Specific immunotherapy, together with avoidance of the allergen and symptomatic treatment, forms part of the treatment of allergic pathology. The oldest, best known and most studied form is subcutaneous immunotherapy (SCIT), whose efficacy, both in the short and the long term, has been widely demonstrated in numerous studies. However, in spite of having been shown to be safe, it is not free of adverse effects and must be administered under the supervision of medical personnel. This has encouraged the search for new ways of administration of similar efficacy, with a good safety profile and good adherence on the patient's side. Sublingual immunotherapy (SLIT) is the most relevant of the different alternatives studied. In this alternative the antigen is administered in the form of drops under the tongue. There are different dosages of administration depending on the allergen involved. The optimum treatment dose has still to be determined, at present a wide range of dosages are found in comparison with subcutaneous immunotherapy. Its mechanism of action is little known although immunological changes have been observed in different studies. SLIT has shown a good safety profile with scarce secondary effects, normally of a local character. Similarly, different clinical tests have been carried out in which its efficacy has been shown in the treatment of respiratory allergy both in children and in adults. For this reason, although there are still unresolved data concerning this way of administering the immunotherapy, it has been proposed by the WHO as a valid alternative to SCIT.

Tolerance of a cluster schedule on the treatment of seasonal allergic respiratory disease with pollen extracts quantified in mass units

In order to evaluate the tolerance of a cluster schedule on specific immunotherapy (SIT), 306 patients were included in a multicenter study. The patients were suffering from rhinoconjunctivitis with/without asthma, caused by sensitization to olive and/or grass pollen. SIT was administered subcutaneously according to a cluster schedule in which the maintenance dose is reached after four visits (3 weeks). The extracts were biologically standardized with major allergens quantified in mass units. Local reactions appeared in 7.2% of the patients and 1.3% of the doses. Systemic reactions (SR) were recorded in 1.2% of the doses administered to 9.5% of the patients. No anaphylactic shock was registered, and all the SR responded fully and rapidly to treatment. There was no difference in SR according to diagnosis or allergen extract used. The majority of SR occurred with the administration of vial of higher concentration (Vial 2: 7 SR (22%), Vial 3: 32 SR (78%), p < 0.05). Of the 32 SR recorded with Vial 3, 13 (41%) were immediate, with no existing association between dose administered and appearance of SR. However, of the 18 delayed SR (56%), 14 occurred after the administration of the first two doses of Vial 3 and four occurred after administration of the second two doses (78% vs 22%, p < 0.05). On the other hand, this regime realized an important saving in cost and time compared to the conventional schedule (1581 fewer doses and 2754 fewer visits were necessary to reach the optimal dose). Considering all these factors, the clinical profile of the proposed regime may be qualified as good. However, future studies are necessary in order to better adjust the schedule to avoid the delayed SR that occurred after the administration of the first two doses of Vial 3.

[Asthma and allergy due to carmine dye]

Cochineal carmine, or simply carmine (E120), is a red colouring that is obtained from the dried bodies of the female insect Dactylopius coccus Costa (the cochineal insect). We have evaluated the prevalence of sensitization and asthma caused by carmine in a factory using natural colouring, following the diagnosis of two workers with occupational asthma. The accumulated incidence of sensitization and occupational asthma due to carmine in this factory are 48.1% and 18.5% respectively, figures that make the introduction of preventive measures obligatory. Occupational asthma caused by inhaling carmine should be considered as a further example of the capacity of certain protein particles of arthropods (in this case cochineal insects) to act as aeroallergens. Carmine should be added to the list of agents capable of producing occupational asthma, whose mechanism, according to our studies, would be immunological mediated by IgE antibodies in the face of diverse allergens of high molecular weight, which can vary from patient to patient. Nonetheless, given the existence of different components in carmine, it cannot be ruled out that substances of low molecular weight, such as carminic acid, might act as haptenes. Besides, since we are dealing with a colouring that is widely used as a food additive, as a pharmaceutical excipient and in the composition of numerous cosmetics, it is not surprising that allergic reactions can appear both through ingestion and through direct cutaneous contact. We find ourselves facing a new example of an allergen that can act through both inhalation and digestion, giving rise to an allergolical syndrome that can show itself clinically with expressions of both respiratory allergy and alimentary allergy.

[Treatment of allergy to mushrooms]

The treatment of patients with respiratory allergy is based on environmental control measures, pharmacological and immunotherapy treatment. The third cause of allergic respiratory disease in our environment is mushrooms, the most frequently involved being the Alternaria class. However, due to the great difficulties in their diagnosis and specific treatment, there are few controlled studies on immunotherapy with mushroom extracts. A clinical test was carried out with a suitable, biologically standardized extract for the diagnosis and treatment of patients allergic to Alternaria. A second phase determined the maximum tolerated dosage of this extract administered through immunotherapy, in depot preparation and in conventional dosage, which was 0.1 mg/ml of Alt a I. This dosage was established as the maintenance dosage in the following phase (double blind test controlled with placebo), in which the efficacy and safety of the immunotherapy with this extract was determined, administered in immunotherapy to the mentioned maintenance dosage, to 28 patients with rhinitis and/or asthma due to allergy to Alternaria. All the patients reached the pre-established maintenance dosage of 1670 BSU. The treatment proved efficient, producing an improvement in the symptoms, respiratory function, subjective evaluation of patient and doctor, and severity of the disease. The immunological response supported the clinical efficacy, with an increase in the IgG and a fall in the IgE over the course of the study. Tolerance to the treatment was excellent, with only two light systemic reactions registered in the 711 dosages administered (0.28% reactions/dosages administered).

[New techniques in the study of asthma]

Asthma is a chronic inflammatory disease of the airways that is functionally characterized by variability of lung function and bronchial hyper-responsiveness. Its diagnosis and management is commonly hampered by the lack of objective parameters. This article reviews additional techniques for evaluating both, lung function (bronchial challenge with adenosin-monophosphate, lung resistance measurement by either the impulse oscillometry system or whole body pletismography) and bronchial immuno-inflammatory response (induced sputum, condensates of exhaled air, monitoring of nitric oxide in exhaled air), as well as our experience with them.

[Anaphylaxis]

Anaphylaxis is a potentially mortal, underdiagnosed clinical picture. The most frequent triggering agents are drugs and foodstuffs. The first therapeutic option, adrenaline, although clearly indicated, is not carried out with the desired frequency due basically to the high number of cases of anaphylaxis that are not diagnosed as such. In patients with a first episode of anaphylaxis, posterior aetiological diagnosis is crucial to avoid the appearance of new episodes. The only case of anaphylaxis in which immunotherapy with the allergen must be evaluated, is that in which the causal agent is the poison of hymenopters.

[Perspectives in the treatment of allergy to latex: immunotherapy]

At present, allergy to latex is an important problem due to the severity of the symptomatology that it produces and the risk groups involved. Complete avoidance of latex is practically impossible, which is why in recent years there has been intense work on standardizing an extract in order not only to improve its clinical diagnosis but also to be able to offer a therapeutic alternative other than avoidance, such as immunotherapy. Since 1998, timely approaches to immunotherapy with latex have been published, with oral desensitization (three patients), subcutaneous (one patient) and sublingual (one patient). In every case there was an evident clinical improvement. At present, subcutaneous immunotherapy with latex, although efficient, is a high risk treatment. Sublingual immunotherapy with latex has recently been commercialized in Spain and we know of its efficacy through the results of an open test on 26 adult patients. The safety expectations are shown to be better than those for subcutaneous immunotherapy.

[Allergy to asparagus]

Asparagus (Asparagus officinalis) is a widely grown vegetable; together with garlic, the onion and the leek, it belongs to the Liliaceae family. Both delayed cell-mediated reactions and IgE-mediated reactions secondary to asparagus have been described. While the former (allergic contact dermatitis) are a fairly common cause of occupational disease, only a few case-reports of IgE-mediated reactions have been published. IgE-mediated reactions can be further grouped into food allergy and reactions due to cutaneous or respiratory exposure, which is often occupational. Anaphylaxis is the most common clinical picture of food allergy, while contact urticaria, rhinitis and asthma, appearing either isolated or associated, are clinical pictures of the latter. Sensitization to different allergens is the likely cause of the different clinical pictures due to asparagus. Their detection and early diagnosis is of prime importance due to the different prognosis and treatment. In the present article we resume our experience over the last 5 years.

[Latex. An important aeroallergen involved in occupational asthma]

Latex has become one of the most frequent aetiological agents of occupational asthma in the last decade, especially amongst health personnel. The prevalence of occupational asthma due to latex in the different affected occupations varies between 2.5 and 10%, figures that give an idea of the magnitude of the problem. Latex proteins, absorbed in the dust of cornstarch, used as a lubricant, are responsible for asthma due to latex gloves. This cornstarch dust that covers the inside of the gloves acts as a vehicle for dispersing allergenic proteins. Latex aeroallergens are found in particles of different dimensions. The levels of latex aeroallergens in the environment capable of causing sensitization and of unleashing symptoms are not well defined. The determination of these levels of exposure to latex is complicated, since with latex one is dealing with a complex mixture of allergens with differing stability and bio-availability. The bioaerosol of latex is mainly produced by the active use of powdered gloves, but rugs or carpets and coverings act as important reservoirs of the allergen. Besides, the movement of people from areas with a high environmental concentration of latex constitutes an important means of dispersing the allergen, and probably ventilation systems as well. As in other cases of occupational asthma, diagnosis in many cases requires that a bronchial challenge be realized. The specific challenge tests through inhalation with latex have been carried out by different methods, which can be grouped by those that use an aqueous extract of latex and those that consist in handling or shaking gloves, which thus generate a dust aerosol. Each method has its advantages and drawbacks as described. Once the sensitized patient begins manifestations of the disease, his prognosis is poor if measures aimed at a maximum reduction of exposure to latex are not applied.

[Immunotherapy with grouped doses]

Once the efficacy and safety of immunotherapy with allergen extracts has been shown, recently it has become evident the need for perfecting those aspects of the treatment that can be improved, such as its dosage form. The conventional dosage of subcutaneous immunotherapy in the phase of dose increase is slow in reaching an efficient level. For this reason other alternative dosages to the conventional one have been tried out, such as grouped dosages, which shorten this period of dose increase. On condition that the safety of the treatment is guaranteed, these doses offer the advantages of reducing the economic cost and the time involved, of reducing the discomfort of the treatment and of improving the patient's adherence to the treatment, and possibly of reaching clinical efficacy more rapidly. Nonetheless, it is not easy to determine the suitable dosage of administration (the shortest and with the least number of adverse reactions) and this article reviews the existing problems when it comes to designing these grouped doses. Finally, we present the results of a comparative study between the conventional dose and a grouped dose, with a double blind design, carried out by us, which shows that the grouped dose is quicker in achieving the desired clinical efficacy, shortens the times of reduction of cutaneous sensitivity to the allergen and of modification of the immunological parameters, all with a low frequency of adverse reactions that is similar to that registered with the conventional dosage.

Occupational asthma from natural rubber latex. Specific inhalation challenge test and evolution

BACKGROUND

Natural rubber latex (NRL) is the most frequent cause of occupational respiratory problems in hospital workers.

OBJECTIVE

To describe the diagnostic methodology, including the specific inhalation challenge (SIC), used on patients diagnosed as having occupational asthma due to NRL in our Allergy Department during a 6-year period from 1989 to 1995.

METHODS

In 19 patients diagnosed as having occupational asthma due to NRL, clinical severity was assessed with a combined score for symptoms and medication use. Skin prick tests with aeroallergens, latex, papain, kiwi and chestnut, total IgE, serum-specific latex IgE, respiratory function study, methacholine test, specific conjunctival test, and SIC test with latex were done.

RESULTS

All but three patients worked in hospitals. All presented urticaria and rhinoconjunctivitis, and six also suffered anaphylaxis, usually preceded by asthma. Clinical fruit allergy was present in eight patients. The latency period was variable (0.25-27 years). The intensity of symptoms was low to moderate. Specific IgE, skin prick, and conjunctival tests to latex were positive in all cases. SICs were done in 12 patients. All of them presented isolated immediate reactions. No adverse reactions were observed. Duration of follow-up ranged from 1 to 7 years. Twenty-six percent of the patients kept their job, 26% changed jobs but remained in health care, and 48% switched to jobs unrelated to health care. Only 16% were free of symptoms without treatment, while 32% needed bronchodilators and 52% needed inhaled steroids. The specific bronchial challenge test was safe, but it did not predict the course of the illness. Duration of exposure and intensity of symptoms did correlate with prognosis, however.

CONCLUSIONS

NRL acts as a common aerollergen. Minor symptoms often precede occupational asthma. The SIC test was safe in the hands of trained technicians. Occupational asthma due to NRL seems to have a poor prognosis.

[Allergy to Anisakis simplex]

Anisakis simplex is a parasite, belonging to the Anisakidae family. The life cycle of the parasite can include one or more intermediary hosts, their final hosts being marine mammals or large fish, in which the larvae develop until the adult stage is reached. Man is an accidental host who acquires the larvae by eating raw or undercooked fish. Since the mid-50s, when the first case studies were published in Holland and Japan, new cases have been emerging in different countries including Spain. Parasitization of man by the living larva is known as anisakiasis, principally giving rise to digestive symptomology, with other rare cases described of invasion of other organs such as the lung, the liver, the spleen, the pancreas, etc. Clinical pictures of allergy to IgE mediated anisakis simplex have also been described: reactions by thermostable antigens of the parasite that develop in spite of the fish being cooked or frozen, and an acute digestive parasitization with allergic symptoms called gastro-allergic anisakiasis. In the diagnosis of anisakiasis and/or allergy to Anisakis, the antecedent of the prior ingestion of fish as well as the clinical accompaniment can form basic data of considerable orientational value, and endoscopy can reveal the presence of the larvae and make possible their extraction. Besides, in cases of allergy the detection test for specific IgE facing Anisakis simplex, and cutaneous tests with fish should be carried out. The best treatment for avoiding this parasitization is prophylactic, avoiding the consumption of raw or undercooked fish, while a fish free diet is necessary in cases of true allergy to the thermostable proteins of the parasite.

Liposome-entrapped D. pteronyssinus vaccination in mild asthma patients: effect of 1-year double-blind, placebo-controlled trial on inflammation, bronchial hyperresponsiveness and immediate and late bronchial responses to the allergen

BACKGROUND

Allergen vaccination is effective in mite-allergic asthma. Liposomes are immunological adjuvants that can act as allergen carriers.

OBJECTIVE

To evaluate the immunological and functional effects of a liposome-entrapped D. pteronyssinus vaccine on mite monosensitive, mild asthma patients.

METHODS

A double-blind, placebo-controlled trial was conducted on 26 asthma patients who randomly received vaccination or placebo for 1 year. The levels of exposure to Der p 1 allergen were constant during the study. Allergen bronchial challenge was made at the beginning (T0) and after 1 year of treatment (T12). The day before and 24 h after the allergen provocation, patients were challenged with methacholine (Mth) (until FEV1 fell by 40%) and blood and sputum samples were obtained. Dose-response curves to Mth were evaluated in terms of Mth-PD20 (dose of Mth that induced 20% drop in FEV1), slope (Mth-DRS) and level of plateau. Blood and sputum eosinophils and serum levels of eosinophil cationic protein (ECP) and intercellular adhesion molecule-1 (ICAM-1) were measured.

RESULTS

Groups were comparable at the start of the trial. At TI2, previous to the allergen challenge, the active group showed higher values of both FEV1 and Mth-PD20 and lower values of Mth-DRS. The number of patients presenting a level of plateau increased in the active group (from two to four) and decreased in the placebo group (from two to one). At T12, before the allergen challenge, serum ECP levels increased in the placebo group and blood eosinophils showed a trend towards lower numbers in the active one. The immediate response and the changes in Mth-DRS values, sputum eosinophils and serum ECP levels following the allergen challenge were attenuated in the active group.

CONCLUSION

Liposome-entrapped D. Pteronyssinus vaccination: (i) protects mild asthma patients from the worsening of asthma due to sustained mite exposure; and (ii) reduces the functional and inflammatory changes induced by allergen bronchial provocation.

[Treatment perspectives: immunotherapy with latex]

Latex allergy currently constitutes a serious problem because of the severity of its symptoms and the at-risk groups it affects. Since complete avoidance of this substance is practically impossible, in the last few years intense efforts have been made to standardize a latex extract with the aim not only of improving clinical diagnosis but also of being able to offer other therapeutic alternatives, such as specific immunotherapy.Since 1998, reports of immunotherapy with oral (three patients) subcutaneous (one patient) and sublingual latex desensitization (one patient) have been published. In all cases, clinical improvement was evident. In 2000, Laynadier published the first pilot study, a phase IIB multicenter, randomized, double-blind, placebo-controlled trial that evaluated the efficacy and safety of specific immunotherapy with latex in patients with occupational allergy. Twenty health care workers without obvious latex exposure and with latex allergy-induced symptoms of rhinitis and/or asthma were included. Treatment started with a 2-day course of rush immunotherapy in hospital and maintenance therapy was continued for 1 year. Efficacy was assessed by symptom and medication scores and by variation in the conjunctival reactivity threshold. The safety of the extract was also evaluated. In the overall analysis of symptom score, the treated group showed a marked improvement and the medication score was significantly lower in patients in the active treatment group than in the placebo group. Concerning safety, almost half the patients receiving active treatment showed local reactions starting with the first injection and four of the nine patients in this group suffered moderate-to-severe systemic reactions. In view of this first clinical trial, it can be concluded that this treatment is effective but that its tolerance is low.A second clinical trial with the same characteristics and extract is currently underway. Its aim is to validate the previous protocol, confirm the efficacy of specific immunotherapy with latex, improve its safety and, if possible, determine the optimal dose.J. Sastre et al. have recently (Formigal 2002) presented the results of the first double-blind study with latex immunotherapy using an extract standardized by the ALK-Abelló-España group. The authors included 24 patients with latex sensitization and symptoms of occupational allergy. To diagnose respiratory allergy, an inhalation challenge was performed in a closed 7-m2 chamber and, in case of contact urticaria, glove-wearing and rubbing tests were performed, using a vinyl glove as negative control. Treatment consisted of a first phase of incremental doses for 14 weeks, with 18 injections, followed by maintenance doses for 6 months. Sixteen patients received active treatment and 8 received placebo. Of the 578 doses administered, adverse effects were observed in 41 (7.1 %). There were 21 immediate systemic reactions (5.7 % of the doses) and 10 delayed systemic reactions (2.6 % of the doses). Adverse effects were more frequent in patients with underlying respiratory disease (p < 0.05). After 6 months' treatment, a clear improvement in the cutaneous response index was found in the active treatment group and in the rubbing and glove-wearing tests. The authors conclude that the immunotherapy tested was a high-risk treatment and that the greatest clinical improvement was found in cutaneous symptoms.In conclusion, although effective, latex immunotherapy is currently a high-risk treatment.

Tolerance of immunotherapy with a standardized extract of Alternaria tenuis in patients with rhinitis and bronchial asthma

We studied the safety of immunotherapy with an Alternaria extract in patients with rhinitis and bronchial asthma. The few studies that have investigated immunotherapy with mold allergens suggest that they cause adverse reactions more frequently than do other extracts. All treatments prescribed by our allergology service with Alternaria immunotherapy between 1988 and 1996 were recorded and analyzed. In all cases a biologically standardized depot extract of Alternaria tenuis containing 5 BU/ml was used according to a conventional immunotherapy schedule. During the study period 129 patients received immunotherapy with Alternaria extract. Of the 3,892 doses given, 1.95% led to adverse reactions, which occurred in 39.5% of the patients. Most of the adverse reactions were systemic and mild, and reproduced the underlying disease. The risk of adverse reactions was significantly higher in children, patients with asthma, and during the initial phase of treatment. Patients who suffered from adverse reactions had a significantly higher level of total and specific IgE. It was concluded that tolerance of Alternaria mold extract was worse than for other allergenic extracts, although most reactions recorded were mild. The risk of adverse reactions was greater in children and patients with asthma, and during the initial phase of immunotherapy.

Comparison of allergen-induced changes in bronchial hyperresponsiveness and airway inflammation between mildly allergic asthma patients and allergic rhinitis patients

Bronchial eosinophilic inflammation and bronchial hyperresponsiveness (BHR) are the main features of allergic asthma (AA), but they have also been demonstrated in allergic rhinitis (AR), suggesting a continuity between both diseases. In spite of not fully reproducing natural allergenic exposure, the allergen bronchial provocation test (A-BPT) has provided important knowledge of the pathophysiology of AA. Our aim was to verify the existence of a behavior of AA and AR airways different from the allergen bronchial challenge-induced airway eosinophilic inflammation and BHR changes. We studied a group of 31 mild and short-evolution AA and 15 AR patients, sensitized to Dermatophagoides pteronyssinus. The A-BPT was performed with a partially biologically standardized D. pteronyssinus extract, and known quantities of Der p 1 were inhaled. Peripheral blood (eosinophils and ECP) and induced sputum (percentage cell counts, ECP, albumin, tryptase, and interleukin [IL]-5) were analyzed, before and 24 h after A-BPT. Methacholine BHR, assessed before and 32 h after the A-BPT, was defined by M-PD20 values and, when possible, by maximal response plateau (MRP). The A-BPT was well tolerated by all the patients. AA presented a lower Der p 1 PD20 and a higher occurrence of late-phase responses (LPR). M-PD20 values decreased in AA, but not in AR, patients. MRP values increased in both groups. Eosinophils numbers and ECP levels increased in blood and sputum from both AA and AR, but only the absolute increment of sputum ECP levels was higher in AA than AR patients (P = 0.025). The A-BPT induced no change in sputum albumin, tryptase, or IL-5 values. We conclude as follows: 1) In spite of presenting a lower degree of bronchial sensitivity to allergen, AR patients responded to allergen inhalation with an eosinophilic inflammation enhancement very similar to that observed among AA. 2) MRP levels increased in both AA and AR patients after allergen challenge; however, M-PD20 values significantly changed only in the AA group, suggesting that the components of the airway response to methacholine were controlled by different mechanisms. 3) It is possible that the differences between AR and AA lie only in the quantitative bronchial response to allergen inhalation.

Identification of allergens involved in occupational asthma due to carmine dye

BACKGROUND

Carmine has been implicated as an etiologic agent of occupational asthma, but the allergens involved have not been yet identified.

OBJECTIVE

To identify the allergens involved in occupational asthma due to carmine dye.

METHODS

An in vitro study based in SDS-PAGE and IgE immunoblotting with carmine and cochineal extracts was performed. Sera from three carmine dye workers diagnosed with occupational asthma induced by carmine dye and from seven nonatopic subjects were used.

RESULTS

Three proteins of around 30, 28, and 17 kD in raw cochineal extract and another protein of 50 kD in the boiled one were demonstrated by SDS-PAGE. Two proteins of around 50 and 28 kD were observed in the carmine extract by the same technique. Specific IgE binding bands at 17 kD in cochineal raw extract, at 50 kD in the boiled one, and at 28 kD in carmine extract were demonstrated by IgE immunoblotting.

CONCLUSIONS

We have identified three allergens of around 17, 28, and 50 kD implicated in occupational asthma of three carmine workers.

Airway inflammation in asthma and perennial allergic rhinitis. Relationship with nonspecific bronchial responsiveness and maximal airway narrowing

BACKGROUND

Eosinophilic airway inflammation is the hallmark of asthma, but it has also been reported in other conditions such as allergic rhinitis. We have tested whether the analysis of cells and chemicals in sputum can distinguish between patients with mild allergic asthma, those with allergic rhinitis, and healthy controls. The relationship between inflammation markers in sputum and nonspecific bronchial hyperresponsiveness to methacholine (BHR) (PD20 and maximal response plateau [MRP] values) was also evaluated.

METHODS

We selected 31 mild asthmatics and 15 rhinitis patients sensitized to house-dust mite. As a control group, we studied 10 healthy subjects. Every subject underwent the methacholine bronchial provocation test (M-BPT) and sputum induction. Blood eosinophils and serum ECP levels were measured. Sputum cell differentials were assessed, and eosinophil cationic protein (ECP), tryptase, albumin, and interleukin (IL)-5 levels were measured in the entire sputum supernatant.

RESULTS

Blood eosinophils and serum ECP levels were higher in asthma patients and rhinitis than in healthy controls, but no difference between asthma patients and rhinitis patients was found. Asthmatics had higher eosinophil counts and higher ECP and tryptase levels in sputum than rhinitis patients or control subjects. Sputum albumin levels were higher in asthmatics than in controls. Rhinitis patients exhibited higher sputum eosinophils than healthy controls. An association between sputum eosinophil numbers and MPR values (r= -0.57) was detected, and a trend toward correlation between sputum ECP levels and PD20 values (r= -0.47) was found in the rhinitis group, but not in asthmatics. No correlation between blood eosinophilic inflammation and lung functional indices was found.

CONCLUSIONS

Induced sputum is an accurate method to study bronchial inflammation, allowing one to distinguish between rhinitis patients and mildly asthmatic patients. The fact that no relationship was detected between sputum inflammation and BHR suggests that other factors, such as airway remodeling, may be at least partly responsible for BHR in asthma.

Effect of current exposure to Der p 1 on asthma symptoms, airway inflammation, and bronchial hyperresponsiveness in mite-allergic asthmatics

The existence of a dose-response relationship between indoor allergen exposure and sensitization has been widely described, but the effect of allergen exposure on asthma activity (symptoms, bronchial hyperresponsiveness [BHR], and inflammation) is not clear. Our aim was to determine the existence of an association among current exposure to mite allergens and symptoms, BHR, and airway inflammation assessed in blood and sputum from asthmatic patients sensitized to Dermatophagoides pteronyssinus. We selected 31 mild and recently diagnosed (12-24 months) asthma patients sensitized to D. pteronyssinus. Allergenic exposure (Der p 1, Der 2) was assessed by a commercial assay based on monoclonal antibodies (mAb), carried out on the dust samples collected from patients' beds in a standardized way. Patients completed an asthma symptom questionnaire and underwent skin tests, methacholine bronchial challenge, and sputum induction. Sputum cell profile was analyzed and eosinophil cationic protein (ECP), tryptase, albumin, and interleukin(IL)-5 levels were quantified in sputum supernatant. Total eosinophil numbers and ECP levels were measured in blood samples. Most patients were exposed to Der p 1 levels under 2 microg/g of dust. Der p 1 exposure was higher among the subjects with positive sputum tryptase detection (P = 0.020). Der p 1 levels showed a trend toward correlation with asthma symptoms (P = 0.066, r = 0.36) and correlated with sputum tryptase levels (P = 0.032, r = 0.42). No relationship between BHR, eosinophilic inflammation, and allergenic exposure was found. Our results suggest that asthma symptoms and lung mast-cell activation are at least partially dependent on current allergen exposure. The lack of correlation between mite exposure, eosinophilic inflammation, and BHR supports the role of other factors that enhance the immunologic response initiated by allergen, increasing the activity of asthma.