Increased risk of asthma at age 10 years for children sensitized to multiple allergens

Phenotyping of immediate-type food allergies based on 10 years of research: A latent class analysis

BACKGROUND

Food allergy is a disease with a diverse and variable natural history, and some patients may react to two or more food antigens. This study aimed to classify and characterize the long-term prognosis of infantile-onset, immediate-type food allergies, focusing on three major antigens in Japan: egg, milk, and wheat.

METHODS

All children who visited our hospital with food allergies, including suspected cases, were prospectively registered in our medical database. Among the children in this database, subjects registered by the age of 1 year with immediate-type symptoms or sensitization to the above three antigens were included. The course of the subjects up to the age of 6 years was analyzed. Cox regression analysis and repeated-measures latent class analysis (LCA) were performed to reveal risk factors and tolerance patterns for food allergies.

RESULTS

We included 915 patients with immediate-type food allergy symptoms and 276 sensitized asymptomatic patients in this study. The number of patients with immediate-type symptoms to egg, milk, and wheat was 609, 443, and 235, respectively. The number of patients with multiple food allergies was 302. The proportion of patients with tolerance to egg, milk, and wheat at 6 years of age was 74%, 69%, and 75%, respectively. LCA revealed 7 classes of prognosis for food allergies. The largest class was transient egg allergy alone (19.6%), and there were severe cases of multiple food allergies (6.5%).

CONCLUSIONS

This study demonstrated the prognosis of food allergy classes in Japan, including multiple food allergies, with 7 classes with its own characteristics.

New Directions in Understanding Atopic March Starting from Atopic Dermatitis

Recent evidence showed that the postulated linear progression of the atopic march, from atopic dermatitis to food and respiratory allergies, does not capture the heterogeneity of allergic phenotypes, which are influenced by complex interactions between environmental, genetic, and psychosocial factors. Indeed, multiple atopic trajectories are possible in addition to the classic atopic march. Nevertheless, atopic dermatitis is often the first manifestation of an atopic march. Improved understanding of atopic dermatitis pathogenesis is warranted as this could represent a turning point in the prevention of atopic march. In this review, we outline the recent findings on the pathogenetic mechanisms leading to atopic dermatitis that could be targeted by intervention strategies for the prevention of atopic march.

Allergic sensitisation did not affect bronchial hyper-responsiveness in children without respiratory tract symptoms

AIM

The potential for immunotherapy to prevent asthma development has become a hot topic. This prompted us to revisit data from an early study that examined allergic sensitisation on bronchial hyperresponsiveness (BHR) in children with and without respiratory symptoms. Unlike previous studies, it used both indirect and direct test methods.

METHODS

The study was conducted in Kuopio, Finland, in 1994 and 247 children (55.1% boys) with a mean age 10.5 ± 1.7 years were recruited using a school survey: 165 with lower respiratory symptoms and 82 healthy controls. Each child underwent a 6-min free-running test and a methacholine test with a cumulative dose of 4900 µg. All participants underwent skin-prick tests: 127were sensitised and 120 were non-sensitised.

RESULTS

There were no significant differences in lung function between the sensitised and non-sensitised children. However, sensitisation was associated with BHR which was measured by both the methacholine test (2400 µg versus >4900 µg, p < 0.001) and the free-running test (-3.5% versus -2.6%, p = 0.042). No such differences were observed among the healthy controls. Sensitisation was a predictor of allergic diseases, and only multisensitisation to a minimum of four allergens increased the incidence of asthma.

CONCLUSION

Allergic sensitisation did not affect BHR in children without respiratory symptoms.