7th Drug hypersensitivity meeting: part two

No abstract availabl

Value-added reporting of specific IgE

status: publishe

Quantification of IgG antibodies to Aspergillus fumigatus and pigeon antigens by ImmunoCAP technology: an alternative to the precipitation technique?

BACKGROUND: We evaluated the ImmunoCAP technique for measurement of IgG specific to Aspergillus fumigatus and pigeon antigens. METHODS: We used ImmunoCAP and precipitation technique to measure concentrations of IgG to A. fumigatus or pigeon antigens in sera from 265 patients and 42 controls. We also evaluated linearity, interference, imprecision, concordance, and diagnostic accuracy of the measuring techniques. RESULTS: The precipitation and ImmunoCAP technique showed moderate concordance (kappa, 0.46 for both A. fumigatus and pigeon antibodies). Specific IgG results for A. fumigatus and pigeon were linear (r = 0.98 and 0.97, respectively), with interrun reproducibility rates of 23% and 14% and maximal interference of 36.5% and 8% by lipid and 24% and 21% by hemolysis, respectively. A. fumigatus antibody concentrations were higher in patients with aspergillosis and allergic bronchopulmonary aspergillosis (ABPA) (median, 103 and 70.1 mgA/L, respectively) than in patients with other pulmonary diseases (median, 18.15-33.40 mgA/L). Antibodies to pigeon antigens were high in patients with hypersensitivity pneumonitis (median, 1024 mgA/L) but also in patients with other pulmonary diseases (median, 445 mgA/L). Antibody titers were substantially higher in patients with other pulmonary diseases and contact with pigeons (median, 1060 mgA/L) than in patients without antigen contact (median, 27.35 mgA/L) (P <0.004). CONCLUSIONS: Agreement between the precipitation and ImmunoCAP technique was 86% for A. fumigatus and 70% for pigeon antigens. Highest concentrations of specific IgG to A. fumigatus were found in patients with aspergillosis and ABPA. Our results suggest that antigen contact was the most important variable affecting the presence of antibodies to pigeon antigen.status: publishe

Defining thresholds of specific IgE levels to grass pollen and birch pollen allergens improves clinical interpretation

Cut-off values and predictive values are used for the clinical interpretation of specific IgE antibody results. However, cut-off levels are not well defined, and predictive values are dependent on the prevalence of disease. The objective of this study was to document clinically relevant diagnostic accuracy of specific IgE for inhalant allergens (grass pollen and birch pollen) based on test result interval-specific likelihood ratios. Likelihood ratios are independent of the prevalence and allow to provide diagnostic accuracy information for test result intervals.publisher: Elsevier articletitle: Defining thresholds of specific IgE levels to grass pollen and birch pollen allergens improves clinical interpretation journaltitle: Clinica Chimica Acta articlelink: http://dx.doi.org/10.1016/j.cca.2015.07.023 content_type: article copyright: Copyright © 2015 Elsevier B.V. All rights reserved.status: publishe

Initial False Negative Specific IgE To Gelatin In Gelatin-Induced Anaphylaxis

status: publishe

Hyper-immunoglobulin M syndrome caused by a mutation in the promotor for CD40L

Hyper-immunoglobulin M (IgM) syndrome (HIGM) is a rare primary immunodeficiency characterized by elevated or normal IgM and absent or markedly decreased amounts of IgG, IgA and IgE. The X-linked form (HIGM1) is the most common type and is caused by mutations in the gene for CD40L, a T-cell surface molecule required for T-cell driven immunoglobulin class switching by B cells. In the present study we have identified a patient with X-linked hyper-IgM who failed to express CD40L on the cell surface of CD4+ T lymphocytes. Sequence analysis of CD40L genomic DNA showed no mutations. CD40L mRNA was absent and sequence analysis of the CD40L promotor revealed a mutation at position −123 from the transcription start site. The mutation in the promotor region likely contributed to the decreased transcription as demonstrated by a luciferase reporter assay