In this issue

Sten Dreborg, the President of the European Society for Pediatric Allergy & Clinical Immunology (ESPACI), has written an editorial outlining the future of the organization in its two roles as an independent Society and as a section for pediatrics within the European Academy of Allergy & Clinical Immunology. There is no doubt that pediatric allergy and clinical immunology are gaining strength by the new association. The future for our discipline is looking good. The identi®cation of cysteinyl leukotrienes as important mediators of airway in ̄ammation and bronchospasm in asthma has been a fascinating story. The subsequent development of antagonist drugs has been a unique development and proof of the principle that must be the prelude to a dramatic proliferation of new modalities of treatment for asthma and related allergic diseases. This is the ®rst time that a group of drugs developed on the basis of insights into pathogenesis of asthma has proved ef®cacious in management. This proves that leukotrienes are important mediators of the disease and, more importantly, indicates that attacking basic mechanisms will bear fruit clinically. A Spanish/German collaboration has produced an excellent review article on the new antileukotriene drugs that describes their development and uses up to the beginning of 1999. Clearly we await the outcome of very important early intervention and head-to-head comparative trials with other anti-asthma drugs in childhood. We have two epidemiological studies looking at risk factors for the development of wheezing illnesses in children. The ®rst, from Oslo, shows that neonatal lung function and smoking in pregnancy are independent risk factors for the development of wheezing illnesses in the ®rst two years of life. These results are very similar to those published recently by a group from London (1). However, the number of subjects included in the Oslo study is markedly larger, making it possible to conduct more convincing logistic regression analyses. As far as early symptoms of bronchial obstruction are concerned, the role of atopy, whether based on family history or raised cord blood IgE, seems more dif®cult to elucidate. It is likely that these factors will have more impact on later persistence of symptoms and we await the longer term follow-up of this sizeable cohort with interest. The second study comes from Spain. Numbers are not suf®ciently large (n5340) to identify factors based on logistic regression analysis. However, there are some very interesting trends. It is fascinating that living in a polluted area reduced the risk for positive bronchodilator responsiveness. Does this mean that asthma is more common in non-polluted areas, as has been shown in East±West Germany comparisons (2), or is it the case that pollution causes irreversible air ̄ow limitation? The paper from Hjern and colleagues is fascinating in suggesting that early life factors in ̄uencing the risk of developing atopic disease may have their effects way beyond the neonatal period and perhaps even up to 6 years of age. Thus, concentrating on neonatal hygiene may only provide part of the answer. The continuous antigenic load over the ®rst years of life may also be important. Studies of moving populations, such as that conducted by Hjern on internationally adopted young men in Sweden, should continue to provide us with important information that can then be investigated in more detail mechanistically. The hygiene hypothesis is being viewed in a new light with the generation of murine studies looking at mycobacterial immunization to inhibit the development of allergic sensitization. The study from Turkey shows that not all mycobacteria have the same effect. Furthermore, in relation to interpretation of the data, it is important to note that this strategy is having its effect when mycobacteria is used as an immunization before primary allergic sensitization. From a human perspective, it will be more important to establish whether this strategy will have any effect after sensitization has occurred. That this may be possible is at least suggested by the GuineaBissau study, showing that active measles infection at an average age of three was associated with less asthma than not having contracted this infection (3). The LinkoÈping group generated another meticulous study of a birth cohort, investigating the development of IgG subclass antibodies to allergens over the ®rst years of life. Atopy is associated with higher levels of IgG subclass antibodies with a particular focus on IgG4, which Pediatr Allergy Immunol 1999: 10: 75±76