ABSTRACT
Type Ⅰallergy is one type of allergic reaction mediated by IgE antibody .Simple, rapid and accurate allergen detection method can be used to identify the allergen of patients , which is of great significance for the prevention , diagnosis and treatment of allergic diseases . In this article , different techniques for in vitro diagnosis of allergen specific IgE antibodies in type Ⅰ allergic reactions were described , important factors affecting in vitro diagnosis of allergens were analyzed , and the future development trend of in vitro diagnosis of allergen specific IgE antibodies were prospected .In order to help clinicians to select more suitable in vitro detection methods in the process of in vitro diagnosis of type Ⅰallergy and to better understand the internal relationship between the allergen specific IgE detection report and clinical symptoms.
ABSTRACT
Las alergias mediadas por IgE (tipo 1) son enfermedades crónicas que afectan a más del 20% de la población en algunos países. Se analizaron muestras de un grupo de 55 trabajadores del IUPOLC, Caracas, Venezuela, que manifestaron presentar síntomas relacionados con Alergias tipo I, mediante el uso de un cuestionario especialmente diseñado para tal fin. En ichas muestras se determinó la IgE Total Sérica por ELISA (Dr. Fooke Laboratorien, Alemania) y simultaneamente se ensayó un panel de IgE específica compuesto por ácaros y hongos de conocida prevalencia local por la técnica de Allergy Screen® (r-biopharm, Alemania), en aras de calcular la sensibilidad diagnósticada de la IgE Total sérica como marcador para el diagnóstico de Alergias Tipo I ante el hallazgo de valores significativos de IgE Específica para los alergenos seleccionados. Se escogieron los valores de referencia de IgE Total utilizados en la mayoría de los laboratorios clínicos de Venezuela. El valor de sensibilidad diagnóstica obtenido en el estudio para la IgE Total sérica fue de 66,67%, con una especificada de 100%. Valor Predictivo VPP de 100%. Valor Predicitivo Negativo 61,29%. Se discutió la posibilidad de que este valor de sensibilidad pudiese ser incluso menor con la inclusión de mayor número de alergenos y/o pruebas de piel. En conclusión, la utilización de la IgE Total sérica como herramienta diagnóstica de primera instancia (tamizaje y/o screening) de alergia tipo I, debe estar acompañada de la historia clínica del paciente y la prescripción de otros ensayos como la IgE específica. Los laboratorios clínicos locales deben procurar la utilización de mejores esquemas de interpretación (valores de referencia) de la IgE Total sérica que contribuyan a un mejor diagnóstico de esta patología.
IgE mediated allergies (Type I)are chronic diseases that effect more than 20% the population in some countries. We analyzed 55 blood samples from workers of Universitary Institute of Scientific Police, IUPOLC Caracas, Venezuela, that presented Allergies related symptyoms at the moment ofthe study. We used a specially designed survey to register that information. We tested serum Total IgE by ELISA method and a specific IgE using an immunoblott nitrocellulose paner composed with mites and molds allergens of well know local prevalence, in order to calculate the diagnostic sensitivity of serum Total IgE as a marker for screening Type I Allergies compared with allergen sensitivities detected on the individuals. We selected the most common reference values for serum Total IgE used in Venezuela. The sensitivity obtained for serum Total IgE was 66,67% specificity 100%, Positive Predictive Value 100%, and Negative Predictive Value 61,29%. We discussed the possibility that the sensitivity obtained for Total IgE could be oven lower if more number of allergens and skin tests were included on the study. We conclude that the use of Total IgE as screening diagnostic tool for allergies must be used together with clinical history of the patient and other assays like i.e. Specific IgE. Local Clinical Laboratories should promote of better interpretation schemes (reference values) for Total IgE that actually helps to a better diagnosis of this disease.
Subject(s)
Humans , Male , Female , Mites/immunology , Hypersensitivity, Immediate/blood , Hypersensitivity/diagnosis , Hypersensitivity/etiology , Hypersensitivity/blood , Blood Chemical Analysis , Fungi , HematologyABSTRACT
The authors investigated the radioallergosorbent test (RAST) for the specific IgE and the prick test with hose dust mite in 129 patients with atopic dermatitis(AD) wit4 four or more family numbers. RAST and prick test results were described according to family background of respiratory atopy(RA) and severity of AD. The results are summarized as follows : l. A comparison between the prick test results and RAST reactions gave a concordance of 88%. The prick test was more sensitive than the RAST. 2. The level of specific IgE in patients with personal history(PH) or family history(FH) of RA was significantly increased compared to those in patients with only AD. 3. In patients without PH and FH of RA, the level of specific IgE in patients with FH of AD was significantly increased compared to those in patients without FH of AD. 4. The level of specific IgE did not reflect the severity of AD. From the above results, it could be concluded that type I allergy to house dust mite is not directly related to AD and it occurs predominantly in those patients with AD wha have a predisposition to RA.