Recommendations for the use of in vitro methods to detect specific immunoglobulin E: are they comparable?

Total and specific immunoglobulin (Ig) E can be detected in vitro using several commercially available methods. The largest share of the global market for these methods is held by the ImmunoCAP technique (Thermo Fisher, previously Phadia), Immulite (Siemens), and Hytec-288 (Hycor). Most comparative studies examine Immulite and ImmunoCAP, which differ methodologically but use similar units of measurement relative to the same standard of total IgE (WHO IgE Standard 75/502). Despite their similarity, these kits differ in their quantification of specific IgE, which varies depending on the allergen studied.Thus, specific IgE results obtained with ImmunoCAP and Immulite are not interchangeable. It is important to bear this in mind, especially when determining cutoff points as predictors of a response to oral challenge with specific food allergens. The method used in practice must be the same as the one in the publication guiding clinical decision making. We analyze differences between ImmunoCAP and ISAC microarray, 2 methods from the same manufacturer used to detect IgE to specific proteins (purified or recombinant).The results show that the IgE values obtained with ImmunoCAP are not equivalent to the corresponding values obtained with the ISAC microarray system.

Allergic hypersensitivity to cannabis in patients with allergy and illicit drug users.

BACKGROUND: Cannabis is the illicit drug most widely used by young people in high-income countries. Allergy symptoms have only occasionally been reported as one of the adverse health effects of cannabis use. OBJECTIVES: To study IgE-mediated response to cannabis in drug users, atopic patients, and healthy controls. METHODS: Asthmatic patients sensitised to pollen, and all patients sensitised to tobacco, tomato and latex, considered as cross-reacting allergens, were selected from a data base of 21,582 patients. Drug users attending a drug-rehabilitation clinic were also included. Controls were 200 non-atopic blood donors. Specific IgE determination, prick tests and specific challenge with cannabis extracts were performed in patients and controls. RESULTS: Overall, 340 patients, mean age 26.9±10.7 years, were included. Males (61.4%) were the most sensitised to cannabis (p<0.001). All cannabis-sensitised patients were alcohol users. Eighteen (72%) of the patients allergic to tomato were sensitised to cannabis, but a positive specific challenge to cannabis was highest in patients sensitised to tobacco (13/21, 61.9%), (p<0.001). Pollen allergy was not a risk factor for cannabis sensitisation. Prick tests and IgE for cannabis had a good sensitivity (92 and 88.1%, respectively) and specificity (87.1 and 96%) for cannabis sensitisation. CONCLUSIONS: Cannabis may be an important allergen in young people. Patients previously sensitised to tobacco or tomato are at risk. Cannabis prick tests and IgE were useful in detecting sensitisation.

In vitro diagnosis of immediate allergic reactions to drugs: an update.

Evaluation of allergic reactions to drugs is difficult because of the poor sensitivity of in vivo tests, which makes controlled administration of the drug necessary to confirm the diagnosis. In vitro tests are important in order to avoid the risks of in vivo testing. In the present review, we describe the different methods for detecting immunoglobulin (Ig) E antibodies that are specific to drugs involved in the development of type I (immediate) reactions. The 2 main in vitro methods are immunoassays and the basophil activation test, both of which have sufficient sensitivity and specificity for the detection of specific IgE antibodies, although with a limited number of drugs, and they have proven complementary to in vivo methods. We show the importance of the allergological workup of the patient within less than 1 year from the occurrence of the allergic reaction in order to obtain positive results in both in vivo and in vitro tests.

Diagnosis and management of immunodeficiencies in adults by allergologists.

Primary immunodeficiencies (PIDs) are genetic diseases that cause alterations in the immune response and occur with an increased rate of infection, allergy, autoimmune disorders, and cancer. They affect adults and children, and the diagnostic delay, morbidity, effect on quality of life, and socioeconomic impact are important. Therapy (gamma-globulin substitution in most cases) is highly effective. We examine adult PIDs and their clinical presentation and provide a sequential and directed framework for their diagnosis. Finally, we present a brief review of the most important adult PIDs, common variable immunodeficiency, including diagnosis, pathogenesis, clinical signs, and disease management.

Contribution of molecular diagnosis of allergy to the management of pediatric patients with allergy to pollen.

BACKGROUND: Component-resolved diagnosis based on recombinant allergens facilitates treatment of multiple sensitization and/or crossreactivity in allergic patients. OBJECTIVE: To assess the usefulness of molecular diagnosis in childhood allergies. METHODS: A total of 162 children aged 4-16 years diagnosed with allergic rhinitis or asthma/rhinitis caused by pollen were referred for recombinant allergen-based diagnosis in 2006. Specific immunoglobulin (Ig) E against pollen allergens and purified recombinant Phleum pratense pollen allergens were measured using an in vitro quantitative assay, and considering the recombinant allergens Phl p 1+Phl p 5 as P pratense--specific allergens and Phl p 7+Phl p 12 as cross-reacting allergens. Conditional probability was calculated to determine the relationship between values for specific IgE against major allergens and those for cross-reacting allergens. RESULTS: Specific IgE antibodies against P pratense were detected in 99.4% of serum samples, and cross-reacting allergens in 46%. Multiple sensitization to pollen was documented in 38% of patients, with Plantago lanceolata as the main cause. Conditional probability calculations showed that patients with specific IgE values of 75-80 kU(A)/L to Phl p 1+Phl p 5 were 75% (95% confidence interval) more likely to present values > or = 2 kUA/L to Phl p 7+Phl p 12. CONCLUSIONS: Our results show that recombinant DNA technology can help diagnose allergy in cases of multiple sensitization and crossreactivity, and is therefore a promising option for improving prognosis and management of allergic pediatric populations.

Guidelines on the clinical usefulness of determination of specific immunoglobulin E to foods.

The diagnostic gold standard for food allergy is challenge with the culprit food, particularly in double-blind placebo-controlled challenge. This approach involves risks and consumes both time and resources. A more efficient system would be desirable. The detection of serum specific immunoglobulin E (sIgE) against the culprit food enables us to establish sensitization, although this is not always accompanied by clinical reactivity. Age, symptoms (immediate/late reaction, local/systemic reaction), concomitant condition (eg, atopic dermatitis, pollinosis) and selection sample criteria (eg, presence of symptoms related to ingestion, positive skin prick test result) can influence the detection and concentration of IgE against foods. We analyze the clinical usefulness of sIgE determination in light of studies in which oral food challenge is used as the diagnostic method. We review clinical usefulness at diagnosis and in the decision to reintroduce the food, as well as the prognostic value of the determination of IgE to foods.

Multiple myeloma with monoclonal IgG and IgD of lambda type exhibiting, under treatment, a shift from mainly IgG to mainly IgD.

A patient with multiple myeloma (MM), who initially presented with a predominant IgG lambda and a minor IgD lambda paraprotein pattern, is described. After chemotherapy, levels of the IgD lambda protein increased and the IgG lambda levels decreased. The following results were obtained when serum IgD was predominant. In the bone marrow, there were three plasma cell populations: a major one containing only delta chains, a minor one containing only gamma chains, and another minor one containing both delta and gamma chains. All these plasma cell populations contained lambda chains. Stimulation of circulating mononuclear cells with pokeweed mitogen (PWM) achieved differentiation of circulating B lymphocytes into plasma cells: 30% with only cytoplasmic delta lambda chains and 10% with only cytoplasmic gamma lambda chains. These IgG-containing plasma cells showed cytoplasmic reactivity with rabbit antiserum raised against monoclonal IgD which was shown to contain specificities recognizing both delta chains and idiotypic determinants present in both serum IgD lambda and IgG lambda. Circulating B lymphocytes were 'monoclonal': almost all expressed surface delta lambda chains, and a small proportion of them expressed both delta gamma and lambda chains. High levels of IgD were detected in the supernatants of all cultures, but high concentrations of IgG were only detected in those from PWM-stimulated cultures with very low levels of IgM and IgA. These findings suggest that plasma cells producing either IgD or IgG were derived from a common B-cell clone. Double paraproteinaemia exhibiting a shift in immunoglobulin production from IgG to IgD has not been previously described.

Humoral immunoresponse of pigeons to Aspergillus fumigatus antigens.

The aim of this study was to develop an immunological model of avian Aspergillosis by studying the humoral response of pigeons to Aspergillus fumigatus antigens. Immunization was performed by administering weekly injections of A. fumigatus extracts for 70 days (10 weeks). A new booster injection was given 270 days (9 months) following the last immunization. Results showed an early Aspergillus-specific humoral immunoresponse which reached a maximum level at 42-63 days (6-9 weeks) post-immunization. Using the ELISA method, it could be observed that A. fumigatus-specific IgG became elevated in the 2nd week and reached a maximum titre at 63rd day (9th week). In contrast, A. fumigatus-specific IgM levels appeared early showing maximum levels at the 2nd week, after which they declined despite the maintenance of antigenic stimulation. Termination of immunization resulted in the decrease of specific humoral immunoresponse with minimal levels of specific antibodies detectable 210 days (7 months) later. A booster injection given at 270 days (9 months) induced a very fast Aspergillus-specific IgM and IgG immunoresponse, reaching levels of antibodies similar to those observed during the immunization period.

Allergy to pistachio: crossreactivity between pistachio nut and other Anacardiaceae.

BACKGROUND: Anaphylaxis against Anacardiaceae nuts is uncommon and the allergens involved still poorly characterized. For this reason two patients with allergy towards pistachio nut (a member of the Anacardiaceae family) have been studied. OBJECTIVE: Identification of immunoallergens present in pistachio nut and analysis of crossreactive antigens in other members of the same plant family, specifically cashew and mango. METHODS: Presence of specific IgE for pistachio and cashew nut and for mango seed and pulp was determined by skin tests and radioallergosorbent assay (RAST). The allergenic profile of pistachio and cashew was analyzed by sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblotting. Crossreactivity between pistachio and the other Anacardiaceae was studied by RAST inhibition. RESULTS: Skin tests were positive for pistachio and cashew in the two children and for mango seed in one. RAST was positive for pistachio and cashew in both patients. On immunoblotting, serum from both patients recognized several pistachio and cashew allergens with a molecular weight ranging from < 14.2-70 kDa. RAST inhibition demonstrated common antigenic determinants between pistachio and cashew nut. Crossreactivity was also found between pistachio nut and mango seed but not with mango pulp. CONCLUSION: Pistachio nut contains several protein allergens able to trigger type I hypersensitivity reactions. These allergens can be found also in cashew nut and mango seed but not in mango pulp.

Minimal inhibitory concentrations of lucknomycin, a new polyenic derivative, for Candida and Aspergillus spp.

The minimal inhibitory concentrations (MICs) of lucknomycin, a new polyenic derivative, were determined for 101 clinical isolates of Candida, 38 clinical or environmental strains of Aspergillus fumigatus, and 30 isolates of A. niger. The most susceptible species were Candida albicans and Candida tropicalis (mean MIC, 0.4 micrograms/ml). Aspergillus spp. were less susceptible, with mean MICs of 0.60 micrograms/ml for Aspergillus niger and 9.2 micrograms/ml for Aspergillus fumigatus.

Antigens of Fusarium solani: types and criteria for immunochemical characterization.

BACKGROUND: There are no established methods for the preparation and standardization of Fusarium solani antigens. This lack of standardization makes it difficult to use these antigens in allergenic diagnostic tests. OBJECTIVE: To obtain an appropriate standardized method for the preparation of the different antigen types of F. solani. METHODS: Production of fungal extracts, followed by biochemical and immunological characterization. RESULTS: The somatic antigens presented the greatest protein content most of these proteins are common to the metabolic and hydrosoluble antigens, particularly those proteins at 35-39 kDa, 29-32 kDa and 15-16 kDa, as detected by electrophoresis and immunoblotting. The hydrosoluble antigens presented the highest protein diversity; these proteins were the most specific, showing minor determinants in common with the other antigens. CONCLUSIONS: It is recommended that a mixture of the different antigen sources be used in order to obtain extracts which would cover the maximum number of diagnostic possibilities.

Síndrome ave-huevo / Bird-egg syndrome

Antecedentes. Se ha descripto una relación entre la hipersensibilidad respiratoria tipo I frente a antígenos aviares y la alergia alimentaria a la yema de huevo. Dicha asociación se denomina síndrome ave-huevo, y el responsable de dicho cuadro es la alfa-livetina o seroalbúmina de pollo, un antígeno presente tanto en la yema del huevo como en las plumas, suero y excrementos de las aves. Materiales y métodos. Estudiamos una paciente con síntomas de alergia alimentaria tras la ingesta de huevo, quien además sufría de síntomas respiratorios (rinitis/asma) causados por la exposición a aves. Se realizaron pruebas cutáneas con huevo, alfa-livetina, pollo crudo y cocido, y plumas. La IgE sérica específica fue identificada por técnica de microarrays de alérgenos (Immuno CAP ISAC). Resultados. Los prick test fueron positivos para alfa-livetina (8 mm), pollo crudo (8 mm) y plumas de gallina (7 mm). La determinación de IgE sérica específica fue de 16,61 (kU/l) para alfa­livetina. Conclusiones. El síndrome ave-huevo es producido por la sensibilización a la alfa livetina, un alérgeno que puede actuar tanto por vía alimentaria como por vía inhalatoria. Según nuestro conocimiento, es el primer caso diagnosticado a través de la técnica de microarray de alérgenos.(AU)

Background: A relationship between type I hypersensitivity with respiratory symptoms due to bird antigens and allergy to egg yolk has been described. This association is known as bird-egg syndrome, which is caused by sensitization to chicken serum albumin (alpha-livetin), present in bird feathers and serum, and egg yolk. Material and methods: We studied one patient with food allergy to egg yolk who also suffered from respiratory symptoms (rhinitis- asthma) caused by exposure to birds. Sensitization to egg yolk and bird antigens was investigated by skin prick test. Specific IgE was investigated using allergens Microarrays (Immuno CAP ISAC). Results:Our patient had a positive skin prick test to: chicken serum albumin (alpha livetin): 8 mm, bird feathers: 7 mm, raw chicken: 8 mm. Specific IgE to alpha livetin was 16.61 (kU/l). Conclusions: Bird-egg syndrome is due to a sensitization to alpha-livetin, an allergen that can act either on the respiratory or the digestive way. In our knowledgement, this is the first case described using allergen Microarrays technique.(AU)

[Comparative study of medical advice and cognitive-behavioral group therapy in the treatment of child-adolescent obesity]. / Estudio comparativo entre el consejo médico y la terapia grupal cognitivo conductual en el tratamiento de la obesidad infantojuvenil.

OBJECTIVE: The aim of this study was to compare the efficacy of medical advice and cognitive-behavioral group therapy in the treatment of primary obesity in children and adolescents 7 to 15 years old. PATIENTS AND METHODS: From five primary care centers 353 subjects (176 boys and 177 girls) were recruited and assigned to three groups. These groups were: medical advice (Group 1), cognitive-behavioral group therapy (Group 2) and those that rejected all treatments (Group 3). Forty variables were controlled and studied for association with prognosis. RESULTS: A significant, but modest decrease in relative body mass index was noted in groups 1 and 2 in the first 6 months, but at two years no differences between the three groups were detected. CONCLUSIONS: It is concluded that cognitive-behavioral group therapy is not more effective than medical advice in our population and neither had a significant effect at two years when compared to no treatment.

Sensitization to Zygophyllum fabago pollen. A clinical and immunologic study.

Zygophyllum fabago is a herbaceous plant found widely in the Mediterranean area. There are no previous reports of its allergenicity. An aerobiologic and clinical survey was conducted in Murcia, southern Spain, to determine the quantity of airborne pollen and establish the possible role of this pollen as a cause of allergic symptoms. With a Hirst volumetric trap, we determined the atmospheric concentrations of this pollen in 1993, 1994, 1995, and 1996. Of 1180 patients tested, 181 (15.34%) had a positive skin test. To determine its allergenicity, we divided 47 patients into three groups: in group 1, all the patients had symptoms of rhinoconjunctivitis plus asthma; in groups 2 and 3, rhinoconjunctivitis. In group 1, we performed a bronchial provocation test (BPT); in groups 2 and 3, we performed nasal provocation (NPT) and conjunctival provocation (CPT) tests, respectively. SDS-PAGE was used to characterize the antigenic fractions and RAST inhibition to determine cross-reactivity with other pollens. The pollen dispersion period is from May to September (445 grains/m3). BPT was positive in 13 of 15 patients, NPT in 14 of 16 patients, and CPT in 13 of 16 patients. RAST inhibition revealed cross-reactivity with Mercurialis, Ricinus, Olea, and Betula. SDS-PAGE identified 25 IgE antibody-binding components, five of which (60, 65, 41, 38, and 15.5/14.7 kDa) were recognized by 40% of the sera. By SDS-PAGE immunoblotting with sunflower antiprofilin rabbit serum and affinity chromatography we established that the Z. fabago extract has profilin. This study shows that this pollen becomes airborne and elicits an IgE response which triggers respiratory symptoms in allergic subjects.

Pollinosis to Ricinus communis (castor bean): an aerobiological, clinical and immunochemical study.

BACKGROUND: Ricinus communis (castor bean) is a species included into the Euphorbiaceae family, common to all the warm regions of the world. Although the allergenicity of its seed is well known, references are scarce regarding the role played by its pollen as a pneumo-allergen. OBJECTIVES: To carry out an aerobiological study of this pollen in the Málaga area (southern Spain); describe the physicochemical characteristics of its most relevant allergens; and to demonstrate the existence of patients with respiratory allergy due to this pollen. METHODS: A Burkard spore trap was used for the aerobiological study from 1992 to 1996. Skin prick tests with castor bean pollen extract were performed to 1946 patients with rhinitis and/or asthma. Specific IgE levels were measured in castor bean-positive SPT patient sera. Immunochemical characterization of the most relevant allergens was performed using electrophoretic techniques. In vitro cross-reactivity studies using positive patient sera were carried out. Nasal challenge tests were done in 32 subjects randomly selected from the sensitized patient group. RESULTS: Castor bean is a perennial pollen with total annual pollen levels never exceeding 1%. One hundred and eighteen (7.7%) patients showed positive prick test (74 rhinitis, 36 rhinitis and asthma, eight asthma). Nine were monosensitized. Specific IgE levels were > or =0.35 PRU/mL in 39 (33%) of patient sera. Nasal challenge test: 10 subjects presented non-specific nasal hyperactivity, 15 were positive and seven negative. The molecular masses and isoelectric points of the main IgE-binding proteins, ranged from approximately 67-15.5/14.5 kDa and approximately 4.5-5.5, respectively. Profilin of the extract was purified by poli-L-proline-Sepharose chromatography and it appeared as one of the most frequent allergens. CONCLUSION: Castor bean pollen is an allergen which causes respiratory (mainly nasal) symptoms.