Evolution of epitope-specific IgE and IgG4 antibodies in children enrolled in the LEAP trial.

BACKGROUND: In the LEAP (Learning Early About Peanut Allergy) trial, early consumption of peanut in high-risk infants was found to decrease the rate of peanut allergy at 5 years of age. Sequential epitope-specific (ses-)IgE is a promising biomarker of clinical peanut reactivity. OBJECTIVE: We sought to compare the evolution of ses-IgE and ses-IgG4 in children who developed (or not) peanut allergy and to evaluate the immunomodulatory effects of early peanut consumption on these antibodies. METHODS: Sera from 341 children (LEAP cohort) were assayed at baseline, 1, 2.5, and 5 years of age, with allergy status determined by oral food challenge at 5 years. A bead-based epitope assay was used to quantitate ses-IgE and ses-IgG4 to 64 sequential epitopes from Ara h 1 to Ara h 3 and was analyzed using linear mixed-effect models. RESULTS: In children avoiding peanut who became peanut allergic, the bulk of peanut ses-IgE did not develop until after 2.5 years. Minimal increases of ses-IgE occurred after 1 year in consumers, but not to the same epitopes as those in children developing peanut allergy. No major changes in ses-IgE were seen in nonallergic or sensitized children. IgE in sensitized consumers was detected against peanut proteins. ses-IgG4 increased over time in most children regardless of consumption or allergy status. CONCLUSIONS: Early peanut consumption in infants at high risk of developing peanut allergy appears to divert the immunologic response to a presumably "protective" effect. In general, consumers tend to generate ses-IgG4 earlier and in greater quantities than nonconsumers do, whereas only avoiders tend to generate significant quantities of ses-IgE.

Current state and future of pediatric allergology in Europe: A road map.

The history of pediatric allergology (PA) in Europe is relatively youthful, dating back to 1984, when a small group of pediatricians founded the European Working Group on Pediatric Allergy and Immunology-later giving rise to ESPACI (European Society on Pediatric Allergology and Clinical Immunology). In 1990, the first dedicated journal, Pediatric Allergy and Immunology (PAI), was founded. There are striking differences across Europe, and even within European countries, in relation to the training pathways for doctors seeing children with allergic disease(s). In 2016, the EAACIClemens von Pirquet Foundation (CvP) organized and sponsored a workshop with the European Academy of Allergy and Clinical Immunology (EAACI) Pediatric Section. This collaboration focussed on the future of PA and specifically on education, research, and networking/ advocacy. The delegates representing many countries across Europe have endorsed the concept that optimal care of children with allergic diseases is delivered by pediatricians who have received dedicated training in allergy, or allergists who have received dedicated training in pediatrics. In order to meet the needs of children and families with allergic disease(s), the pediatric allergist is highly encouraged to develop several networks. Our challenge is to reinforce a clear strategic approach to scientific excellence to across our member base and to ensure and enhance the relevance of European pediatric research in allergy. With research opportunities in basic, translational, clinical, and epidemiologic trials, more trainees and trained specialists are needed and it is an exciting time to be a pediatric allergologist.

Interobserver variability in the detection of mediastinal and hilar lymph nodes on CT in children with suspected pulmonary tuberculosis.

BACKGROUND: The presence of mediastinal or hilar adenopathy is critical for the diagnosis of pulmonary TB. Interobserver variability in the detection of lymphadenopathy on CT in children affects the usefulness of CT as a gold standard. OBJECTIVE: To determine the interobserver variability for the detection of hilar and mediastinal adenopathy on CT in children. MATERIALS AND METHODS: One hundred children with clinically suspected pulmonary TB were prospectively recruited for CT scanning of the chest. Four observers reviewed the scans independently for the presence of lymphadenopathy at predetermined sites. Overall Kappa statistic was determined for each recognised site of mediastinal and hilar lymphadenopathy. RESULTS: Kappa statistics showed that observers only agreed moderately in their detection of lymphadenopathy. The site of best agreement was the right hilum, followed by the subcarinal, right paratracheal and precarinal locations. Observers differed most at the anterior mediastinum and left hilum. The best Kappa statistic was for the overall presence of lymphadenopathy taking all sites into account. CONCLUSIONS: Imaging techniques that are considered the gold standard for particular diseases must be validated pathologically, and if this is not possible, interobserver variability should be evaluated. CT is considered the gold standard for detecting lymphadenopathy, but we have shown only moderate agreement between readers. Readers had difficulty in distinguishing lymphadenopathy from normal thymus and were unable to distinguish normal from pathological nodes without a predetermined size threshold for abnormality. The right hilum and the sites around the carina are the most reliable for the reported presence of lymphadenopathy.