Sensitization rates of causative allergens for dogs with atopic dermatitis: detection of canine allergen-specific IgE

Allergen-specific IgE serology tests became commercially available in the 1980s. Since then these tests have been widely used to diagnose and treat allergic skin diseases. However, the relationship between a positive reaction and disease occurrence has been controversial. The purpose of this study was to evaluate allergens using a serologic allergy test in dogs with atopic dermatitis (AD). Dogs clinically diagnosed with AD (n=101) were tested using an allergen-specific IgE immunoassay. Among the total 92 environmental and food allergens, house dust and house dust mites were the most common. Several allergens including airborne pollens and molds produced positive reactions, and which was considered increasing allergens relating to the climate changes. The presence of antibodies against staphylococci and Malassezia in cases of canine AD was warranted in this study. Additionally, strong (chicken, turkey, brown rice, brewer's yeast, and soybean) and weakly (rabbit, vension, duck, and tuna) positive reactions to food allergens could be used for avoidance and limited-allergen trials.

Frecuencia de sensibilización alimentos y aero-alergenos en pacientes recibidos en el laboratorio de Corpodiagnostica C.A. durante el periodo 2010-2011 / Frequency of sensitization for food and aero-allergens in patients reciived in a Venezuelan laboratory during 2010-2011 period

La alergia tipo I se ha definido como una reacción inmunológica adversa mediada por IgE que se produce después de una exposición repetida al alérgeno. La prevalencia de las alergias ha aumentado considerablemente en los últimos 20 años, lo que aumenta la necesidad del estudio de la respuesta a varios alérgenos. El objetivo fue evaluar la frecuencia de sensibilización a alimentos y aero-alérgenos en los pacientes referidos al Laboratorio de Corpodiagnostica C.A. durante el periodo 2010-2011. Se determinó niveles de IgE específica a 2445 pacientes, usando el método inmunoblot in vitro RIDA Allergy-screen (r-Biopharm, Alemania). La tasa de sensibilización total medida por IgE específica a alimentos fue de 30,43%, donde los alimentos más comunes fueron Leche, Queso, Trigo, Maíz y Cerdo; mientras que la tasa de sensibilización para aero-alérgenos fue de 46,16%; de los cuales los más comunes fueron los ácaros mayores y B. tropicalis. Este estudio provee de una herramienta importante para la identificación de los alérgenos alimentarios y respiratorios de mayor prevalencia en la población venezolana.

Type I allergy had been defined as an adverse immunologic reaction mediated by IgE that occurs after a repeated exposure to the allergen. The prevalence of the allergies has increased considerably in the last 20 years, thus increasing the need of study the response to several allergens. The objective was to evaluate the frecuency of foods and respiratory allerges sensitization in patients referred to Corpodiagnostica Laboratory (Caracas, Venezuela, ISO 9001:2008 certified laboratory) in the period that correspond from January 2010 to July 2011. We determinated specific IgE levels to 2445 patients, by the in vitro RIDA® Allergy-screen immunoblot method (r-biopharm®, Germany). The total sensitization rate mediated by specific IgE to food allergen was 30,43% where the foods most common were milk, cheese, wheat flour, corn and pork; while the sensitization for aero-allerges was 46,16%; the most common were the major mites and B. tropicalis. This study provides an important tool for the identification of food and aero-allergens with major prevalence in the Venezuelan population.

Cord Serum Screening Test and the Newborns Allergic Status.

OBJECTIVE: To evaluate the predictive value of a cord serum screen test and possible subsequent development of allergic disease in infants. DESIGN: Cohort study. SETTING: 100 pregnant women were randomly recruited for the study. METHODS: The maternal serum and the cord serum of their matched newborn were analyzed for total serum immunoglobulin E (IgE), gamma interferon (g IFN), house dust mite- Dermatophagoides pteronyssinus allergen (Der p1) and Blomia tropicalis allergen (Blo t5) using immunoassay methods. All infants were followed up for one year. RESULTS: Infants who had allergic diseases in the one year follow-up (n=45) had significantly (P < 0.001) elevated IgE, Der p1, Blo t5, and significantly low g IFN levels in cord serum as compared to the same parameters of infants who did not develop allergic disease in the one year follow-up (n=43). CONCLUSION: In utero exposure to HDM allergens Der p1 and Blot5 is prevalent. We have successfully established a cord serum screening test for predicting allergic diseases in infancy with 93% specificity and sensitivity.

Allergic Asthma and Rhinitis Caused by Household Rabbit Exposure: Identification of Serum-Specific IgE and Its Allergens

Although rabbits are common domestic pets, severe respiratory allergic reactions to rabbits in households are unusual. Ory c 1, a 17-kDa glycoprotein found in saliva and fur, has previously been identified as a major rabbit allergen. In this report, we describe the cases of three patients with rabbit allergy who presented with asthma and/or rhinitis while living in households with detectable levels of serum-specific IgE and major IgE binding components. Three patients with rabbit allergy and 18 unexposed nonatopic healthy controls were enrolled. Enzyme-linked immunosorbent assays (ELISA) for serum-specific IgE and IgG4 to rabbit epithelium and inhibition ELISA were performed followed by sodium dodecye sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and IgE immunoblotting. All three patients with rabbit allergy had high serum-specific IgE antibody levels compared with controls. The results of the inhibition ELISA showed significant inhibition with the addition of rabbit epithelium, whereas no significant inhibition was noted with the addition of cat and dog epithelia. Two IgE-binding components with molecular weights of 16 kDa and 67.5 kDa were identified by IgE immunoblotting. In conclusion, rabbit exposure may induce IgE-mediated bronchial asthma and/or rhinitis in domestic settings.

Diagnóstico de alergia a baratas no ambiente clínico: estudo comparativo entre o teste cutâneo e IgE específica / Use of the skin prick test and specific immunoglobulin E for the diagnosis of cockroach allergy

OBJETIVOS: Comparar a prevalência da sensibilização a baratas (Blattella germanica e Periplaneta americana) em crianças com e sem asma, verificando a concordância entre testes cutâneos e IgE específica bem como determinar a relação entre a sensibilização a baratas e níveis séricos de IgE total. MÉTODOS: Foi realizado um estudo caso-controle, envolvendo 76 crianças asmáticas e 42 não asmáticas, entre 6 e 14 anos de idade, em Recife, Brasil. Todas as crianças submeteram-se ao teste cutâneo e dosagem sérica de IgE específica para B. germanica e P. americana e determinação sérica da IgE total. RESULTADOS: As crianças asmáticas apresentaram maior positividade aos testes cutâneos para B. germanica (27,6 versus 4,8 por cento) e P. americana (27,6 versus 2,4 por cento) que aquelas do grupo controle. A concordância entre o teste cutâneo e a IgE específica foi razoável para B. germanica (Kappa = 0,25) e fraca para P. americana (Kappa = 0,17). A média geométrica da IgE total foi 591,70 kU/L entre pacientes asmáticos e 345,85 kU/L entre os controles, não havendo diferença estatisticamente significante. Em pacientes com testes positivos para baratas, a média geométrica da IgE total foi significativamente maior em comparação aos pacientes cujos exames foram negativos. CONCLUSÃO: A sensibilização a baratas foi associada à asma. O teste cutâneo pode refletir mais apropriadamente uma sensibilização a baratas clinicamente relevante que a IgE específica.

Measurement of IgE and IgG subclass antibodies to whole body antigen and two major allergens (Der fI & Der fII) of Dermatophagoides farinae in normal subjects and asthmatics

House dust mites have been known as the most important allergen in respiratory allergic diseases. Among several mite allergens, group I and group II antigens were recognized as major allergens. We measured specific IgE and IgG subclass antibodies against whole body antigen (WBA) and two major allergens of Dermatophagoides farinae (Der fI and Der fII) in sera from 66 adults with asthma (asthma group) and 34 normal subjects (healthy group) by ELISA. The mean O.D. values of WBA-specific IgE and IgG subclass antibodies in 100 studied sera were significantly higher than those of the two major allergens (p<0.001) and the level of Der fII- IgG1, IgG4 and IgE were higher than those of Der fI but IgG2 of Der fI was higher than that of Der fII (p< 0.001). The level of IgG4 of WBA were significantly higher in the atopic group than in the nonatopic group (1.280 +/- 0.634 v.s. 0.8290 +/- 0.388, p< 0.001), but the WBA- IgG1, IgG2, IgG3 were not different between the two groups. Among IgG subclass antibodies of Der fI, IgG2 was significantly higher in the nonatopic group than in the atopic group (1.7770 +/- 0.255 v.s. 1.636 +/- 0.390, p< 0.05) but there were no differences in IgG1, IgG3, and IgG4. Among IgG subclass antibodies of Der fII, IgG2 (1.534 +/- 0.380 v.s. 1.3010 +/- .431, p< 0.05) and IgG4 (1.09650 +/- .567 v.s. 0.708 +/- 0.146, p< 0.001) were significantly higher in the atopic group than in the nonatopic group. IgE antibodies to WBA, Der fI and Der fII were significantly higher in the atopic group (p< 0.001). There were significant correlationships between the levels of IgE and IgG4 of WBA (r = 0.60), Der fI (r = 0.33) and Der fII (r = 0.72). Even though there were no differences in the levels of allergen specific IgE and IgG subclass antibodies between nonatopic healthy and nonatopic asthmatic groups, the number of sera with prominent level of IgG2 of WBA were more common in the nonatopic asthmatic group (69% in nonatopic asthma group v.s. 28% in nonatopic healthy group, X2-test, p< 0.01).