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Abstract Background The incidence of childhood type 1 diabetes (T1D) incidence is rising in many countries, supposedly because of changing environmental factors, which are yet largely unknown. The purpose of the study was to unravel environmental markers associated with T1D. Methods Cases were children with T1D from the French Isis-Diab cohort. Controls were schoolmates or friends of the patients. Parents were asked to fill a 845-item questionnaire investigating the child’s environment before diagnosis. The analysis took into account the matching between cases and controls. A second analysis used propensity score methods. Results We found a negative association of several lifestyle variables, gastroenteritis episodes, dental hygiene, hazelnut cocoa spread consumption, wasp and bee stings with T1D, consumption of vegetables from a farm and death of a pet by old age. Conclusions The found statistical association of new environmental markers with T1D calls for replication in other cohorts and investigation of new environmental areas. Trial registration Clinical-Trial.gov NCT02212522 . Registered August 6, 2014.

The aim of this study was to define levels of egg white- and yolk-specific IgE antibodies that would confirm the diagnosis of egg allergy with a positive predictive value (PPV) of 100%. The study was carried out on 185 children with suspected food allergy recruited consecutively at the Children’s Hospital. One group included 100 children with a positive hen’s egg oral food challenge (OFC) test. They were compared with 85 children with peanut allergy but not egg allergy (negative egg OFC). We analyzed the children’s clinical symptoms, family history of atopic diseases, skin prick test results (SPT) with raw egg white and yolk, serum samples for specific IgE antibodies to egg white and yolk using the Pharmacia Cap system FEIA method, open controlled challenge tests with whole raw egg or double-blind controlled food challenges with peanut. Median age was 2.1 years (range 0.8–15 years). The median skin reaction to the egg extract was 11.3 mm (range 0–25 mm) in the first group and 5.5 mm in the second (P = 0.00001). We found a higher level of egg white-specific IgE antibodies in the egg allergy group (22.5 vs. 0.76 kUA/l, P = 0.000001) and also a higher level of yolk-specific IgE antibodies (6 vs. 0.35 kUA/l, P = 0.0001). For the egg white antibodies, a threshold value equal to or greater than 7.5 kUA/l resulted in a PPV of 100% and a negative predictive value (NPV) of 68%. For the yolk-specific antibodies, a threshold value equal to or greater than 5.5 kUA/l resulted in a PPV of 100% and a NPV of 52%.Conclusion. – Our study demonstrated better sensitivity for egg white-specific IgE antibodies and better specificity for egg yolk-specific IgE antibodies. Both measurements are useful for the diagnosis of egg allergy in children. In addition, with an egg white-specific IgE antibody level equal to or greater than 7.5 kUA/l and a yolk-specific IgE antibody level equal to or greater than 5.5 kUA/l, the patient can be said to be egg-allergic with nearly 100% certainty. [Copyright &y& Elsevier]