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This editorial opens this new issue of Pediatric Allergy and Immunology, the leading journal in the field, aiming at providing you with the latest science and state‐of‐the‐art review articles. Two educational articles begin this issue: the first addressing one of the most common clinical challenge practicing pediatric allergists are facing, allergic conjunctivitis. Jean‐Luc Fauquert, one of the very few experts having triple exper‐ tise in pediatrics, allergy, and ophthalmology, reviews diagnosis and management of the various presentation of allergic conjunctivitis and pro‐ vides very practical advice which will undoubtedly update your clinical practice.1 The second educational article is a rostrum addressing oral immunotherapy (OIT) for treatment of food allergy, a topic that has been extensively studied in the latest articles published in this journal.2‐5 In addition, a recent position statement of the European Academy (EAACI) has evaluated the scientific evidence behind OIT and concluded that “Overall, trials have found substantial benefit for patients undergoing OIT”.6 Nevertheless, questions remain to the practicing allergists, and Giovanni Pajno et al7 review them with a critical look in a rostrum article. Research communications represent the core of this issue of PAI, and the first I would like to bring to your attention is by Stephanie Metzler and colleagues who investigated the association between pre‐ and post‐natal antibiotic expo‐ sure and subsequent development of allergies in 1080 children from the PASTURE birth cohort.8 Questionnaires sub‐ mitted to the mothers gathered information on antibiotic exposure during the third trimester of pregnancy up to the first year of life. These data were matched to atopic dermatitis, food allergy, respiratory allergies, and allergic sensitiza‐ tion up to 6 years of life. The results showed that exposure to prenatal antibiotics was positively associated with atopic dermatitis and food allergy in childhood, in particular on diseases developing in the first year of life. Interestingly, no associations were found between prenatal antibiotic exposure and respiratory allergies. An analysis published earlier in this journal of four birth cohorts found a relation between antibiotic use and the risk of developing asthma, but no risk for asthma exacerbations.9 A meta‐analysis published earlier found a significant but low risk of asthma when antibiotics were given during the second and third trimester of pregnancy.10 Overall, these studies suggest a risk for allergy devel‐ opment after antibiotic use, recommending restriction of antibiotic use to those cases really needing them. In the second of my highlighted articles, Marjolein Kooijman and colleagues investigated whether adaptation of fetal umbilical, cerebral, and pulmonary blood flows were associated with wheezing, decreased lung function, and asthma in childhood.11 The study population was recruited from the Generation R study, a Dutch prospective birth cohort. Findings from this cohort have been reported earlier in PAI.12‐15 Here, information on early‐life wheeze was obtained from question‐ naires, and children had pulmonary function tests performed between 8 and 12 years of age. Although results showed a relationship between a higher umbilical artery pulsatility index (PI) and umbilical artery PI/cerebral artery PI ratio, indicating fetal blood flow redistribution at the expense of the trunk, with more early wheezing, this association was not statistically significant. The authors conclude that despite the small effects observed here, this hypothesis deserves further investiga‐ tion. Intrauterine factors and later development of asthma have been published earlier in PAI by Ogawa et al16 who showed that beta2‐receptor agonists taken by the mother during pregnancy were associated with later asthma in a dose‐dependent way. Also, more generally, it is known that maternal ingestions of various nutrients such as folates,17 or fish,18 can influence asthma in childhood. The third research article featured in this editorial reports on primary immunodeficiencies. Mahmood Tavassoli and colleagues report on a large Iranian cohort of patients with hyper‐IgE syndrome.19 Clinical allergists are often faced with this differential diagnosis in patients with atopic diseases and much elevated total serum IgE levels. Over a 37‐year period, these investigators have enrolled patients with hyper‐IgE syndrome and here report clinical characteristics as well as laboratory features at diagnosis. In addition, they have determined genetic mutation analysis in a subgroup of patients in the STAT3 and DOCK8 genes. They further discuss the contribution of this genetic analysis to the clinical diagnosis and evoke possible future therapeutic modalities in these patients. Primary immunodeficiencies are one of the major topics of interest of PAI—readers will find further recent reports addressing this topic in previous issues of the journal.20‐25 Stephanie Metzler