Palivizumab prophylaxis in preterm infants and subsequent wheezing/asthma: 10-year follow-up study

BACKGROUND

Respiratory syncytial virus (RSV) causes not only infantile recurrent wheezing but also the development of asthma. To investigate whether palivizumab, an anti-RSV monoclonal antibody, prophylaxis given to preterm infants during the first RSV season reduces the incidence of subsequent recurrent wheezing and/or development of asthma, at 10 years of age.

METHODS

We conducted an observational prospective multicenter (52 registered hospitals in Japan) case-control study in preterm infants with a gestational age between 33 and 35 weeks followed for 6 years. During the 2007-2008 RSV season, the decision to administer palivizumab was made based on standard medical practice (SCELIA study). Here, we followed these subjects until 10 years of age. Parents of study subjects reported the patients' physician's assessment of recurrent wheezing/asthma, using a report card and a novel mobile phone-based reporting system using the internet. The relationship between RSV infection and asthma development, as well as the relationship between other factors and asthma development, were investigated.

RESULTS

Of 154 preterm infants enrolled, 113 received palivizumab during the first year of life. At 10 years, although both recurrent wheezing and development of asthma were not significantly different between the treated and untreated groups, maternal smoking with aeroallergen sensitization of the patients was significantly correlated with physician-diagnosed asthma.

CONCLUSIONS

In contrast to the prior study results at 6 years, by 10 years palivizumab prophylaxis had no impact on recurrent wheezing or asthma, but there was a significant correlation between maternal passive smoking with aeroallergen sensitization and development of asthma by 10 years of age.

Indoor Aeroallergen Sensitization and Associated Factors in Hospitalized Children with Asthma Exacerbations

Background

Allergic asthma represents the most popular phenotype of childhood asthma and is characterized by eosinophilic airway inflammation associated with specific immunoglobulin E (IgE) antibodies sensitization to various allergens, as evidenced by serology or skin prick test.2 Sensitization to indoor aeroallergens is associated with severe asthma and severe asthma exacerbations.

Objective

This study aimed to identify the prevalence of aeroallergen sensitization and its associated factors in children with an asthma exacerbation in Vietnam.

Methods

A cross-sectional study was conducted at Children's Hospital 1, Ho Chi Minh City (HCMC). Children who were aged 3 to 15 and admitted to the hospital with moderate or severe asthma exacerbation were recruited to the study. Data was collected from interviews and medical records. SPT was used to identify aeroallergen sensitization. The association between school-age, living area, and passive smoking with the odds of aeroallergen sensitization was assessed using a multivariable logistic regression.

Results

The prevalence of aeroallergen sensitization was 82.6% and this figure in school-age children was higher than that in preschool-age ones (93.8% vs 72.1%, p=0.001). School-age, living in HCMC, and passive smoking significantly increased the odds of aeroallergen sensitization in asthmatic children with adjusted OR [95%CI] as 6.9 [2.1-23.3], 4.1 [1.5-11.5], and 2.9 [1.0-8.4], respectively. Asthmatic children with aeroallergen sensitization required more hours to resolve an asthma exacerbation than those without (22.4 vs 15.2, p=0.006).

Conclusion

Aeroallergen sensitization was common in hospitalized children with moderate or severe asthma exacerbation. It is necessary to establish environmental policy and screening practices of aeroallergen sensitization to improve the quality of asthma management for Vietnamese children.

Molecular IgE sensitization profiles of urban and rural children in South Africa

BACKGROUND

Allergens can act as disease-triggering factors in atopic dermatitis (AD) patients. The aim of the study was to elucidate the molecular IgE sensitization profile in children with and without AD living in urban and rural areas of South Africa.

METHODS

Specific IgE reactivity was assessed in 166 Black South African children aged 9-38 months using a comprehensive panel of microarrayed allergens. According to clinical characterization children fell in four groups, urban AD cases (n = 32), urban controls (non-AD, n = 40), rural cases (n = 49) and rural controls (non-AD, n = 45).

RESULTS

IgE reactivity to at least one of the allergens was detected in 94% of urban and 86% of rural AD children. House dust mite (HDM; 81% urban, 74% rural AD) and animal-derived allergens (50% urban, 31% rural AD) were the most frequently recognized respiratory allergens, whereas IgE to pollen allergens was almost absent. Urban AD children showed significantly higher frequency of IgE reactivity (50%) to mouse lipocalin, Mus m 1, than rural AD children (12%). The most frequently recognized food allergens were from egg (63% urban, 43% rural AD), peanut (31% vs 41%), and soybean (22% vs 27%), whereas milk sensitization was rare. α-gal-specific IgE almost exclusively occurred in rural children (AD: 14%, non-AD: 49%).

CONCLUSION

Molecular allergy diagnosis detects frequent IgE sensitization to HDM, animal but not pollen allergens and to egg, peanut, and soy, but not milk allergens in African AD children. Urban AD children reacted more often to Mus m 1, whereas α-gal sensitization is more common in rural children likely due to parasite exposure.

Prevalence of food allergen and aeroallergen sensitization among children in Sichuan province

Food allergen and aeroallergen sensitization are common allergic diseases worldwide, with widely varying estimates of prevalence in children. Our study investigated the characteristics of ingestion and inhalation allergy among children from Sichuan province in Southwest China, so as to get public awareness of these disorders.A total of 1722 children between 0 and 14 years' old were enrolled in this study. They were outpatients in the West China Second University Hospital during June 2019 to September 2019. Serum specific IgE specific to 10 types of food allergen and 10 types of aeroallergen were estimated. Nutrition indicators were tested by electrochemical luminescence.59.70% children were allergic to at least 1 allergen, comprising 24.90% to aeroallergen and 38.81% to food allergen, respectively, whereas 36.28% children were allergic to both aeroallergen and food allergen. Milk was the most common food allergen, and egg came in second place. With regard to aeroallergen, house dust mite held the maximum proportion (65.02%), whereas dust mite followed behind. Inhalation allergy was more commonly seen in boys than girls. Bronchitis was the most common symptom of both allergies. In addition, the highest incidence age for children to be sensitive to food allergen and aeroallergen were 0∼2 years' old and 3∼5 years' old, respectively. It is worth mentioning that there was no significant difference in nutritional status between children with or without allergic diseases.Our findings reveal that milk, egg, house dust mite, and dust mite are the most common allergens among children in Sichuan province. Boys are more susceptible to aeroallergen than girls. Furthermore, the prevalence of ingestion and inhalation allergy varies from different age groups, and has no correlation with nutritional status. In brief, the analysis of the pattern of food allergen and aeroallergen sensitization is invaluable to effective diagnosis and treatment of allergic diseases.

Environmental factors associated with allergy in urban and rural children from the South African Food Allergy (SAFFA) cohort

BACKGROUND

The prevalence of allergic diseases differs in urban and rural populations.

OBJECTIVE

We sought to assess associations between environmental and dietary factors with allergic diseases in urban and rural South African children.

METHODS

Toddlers aged 12 to 36 months were assessed for food allergen and aeroallergen sensitization, atopic dermatitis, allergic rhinitis, asthma, and challenge-proved food allergy. Information was collected on family history of allergic diseases, household size, socioeconomic status, delivery mode, antibiotic and probiotic use, exposure to fermented and unpasteurized milk, antihelminth treatment, sunlight exposure, pet and farm animal exposure, cigarette smoke, and household cooking and heating fuels. Antenatal exposures to pets, livestock, and cigarette smoke were assessed. A subsection completed questions on consumption of fruits and vegetables, fast foods, soft drinks/fruit juices, and fried/microwaved meat.

RESULTS

Risk and protective factors differed between urban and rural settings. Exposure to farm animals in infants and their mothers during pregnancy was protective against allergic outcomes in the rural population. Consumption of unpasteurized milk is uncommon in this group of rural children and is unlikely to be an important factor in rural protection. In urban children birth by cesarean section is associated with food allergy, and consumption of fermented milk products is associated with reduced asthma and atopic dermatitis. In both cohorts antenatal maternal smoking and environmental smoking exposure were predominantly associated with asthma, and consumption of fast foods and fried meats were associated with allergy.

CONCLUSION

In this rural environment exposure to livestock is the strongest protective factor. In urban communities, where animal contact is rare, risk factors include cesarian section, and protective factors include consumption of fermented milk products. Modifiable risk factors urgently require interventions to prevent increasing allergy rates in countries undergoing rapid urbanization.

Nutrition and allergic diseases in urban and rural communities from the South African Food Allergy cohort

This study describes and compares allergic diseases and sensitization in urban and rural children in the SAFFA study cohort as well as infant feeding patterns and nutritional status. We assessed the relationship between nutritional status, breastfeeding, complementary feeding patterns, and atopic diseases including aeroallergen and food allergen sensitization, self-reported atopic dermatitis, allergic rhinitis, asthma, and challenge-proven food allergy (FA).

METHODOLOGY

A total of 1185 urban and 398 rural toddlers aged 12-36 months were screened for food sensitization (FS) and FA using skin prick testing and oral food challenges. Of these, 535 and 347, respectively, were additionally screened for aeroallergen sensitization. Information was collected on infant feeding practices, and anthropometric measurements and clinical signs for atopy were documented.

RESULTS

Markedly higher rates of allergy (asthma 9.0% vs 1.0%, eczema 25.6% vs 2.0%, rhinitis 25.3% vs 3.3%, and FA 2.5% vs 0.5%) exist in urban vs rural children. 13.1% unselected urban South African children were sensitized to aeroallergens compared to 3.8% of their rural counterparts and 9.0% to any food compared to 0.5%. Exclusive breastfeeding duration was longer, and there was a later introduction of allergenic foods in rural communities. Obesity rates were similar between the two groups, but rural children were more likely to be stunted. Being overweight was associated with asthma in urban but not rural settings. In the urban cohort, children with FS and allergy were thinner than their peers.

CONCLUSION

Allergy and sensitization rates are significantly higher in unselected urban South African toddlers than their rural counterparts. Risk and protective factors for allergy and atopy may differ between urban and rural settings.

Predictors of emergency department use in children with persistent asthma in metropolitan Atlanta, Georgia

BACKGROUND

Racial disparities are evident among children with asthma in the United States, with non-Hispanic black children at particularly high risk for poor asthma outcomes, including frequent emergency department (ED) use for asthma exacerbations.

OBJECTIVE

To compare asthma features in non-Hispanic black vs white children in Atlanta, Georgia, and determine what clinical features predict future ED use for asthma.

METHODS

Self-reported black and white children 6 to 17 years of age with persistent asthma treated with controller medications completed medical history questionnaires, lung function testing, aeroallergen sensitization testing, and venipuncture. Medical records were reviewed for asthma-related ED visits for 12 months after the initial study visit.

RESULTS

A total of 276 children were enrolled. Black children, compared with white children, resided in more disadvantaged zip code areas and were more likely to have public insurance. Black children also had more features of asthma severity and more ED visits during the study period. Predictors of ED use, aside from a previous ED visit, differed by race. After adjustment for socioeconomic status, predictors of ED use in white children included an ED visit in the previous year and sensitization to pets and dust; in black children, predictors included ED use in the previous year, the number of asthma controller medications, forced expiratory volume in 1 second less than 80% predicted, blood eosinophil count greater than 4%, and mold sensitization.

CONCLUSION

Asthma features and ED use differ between black and white children in metropolitan Atlanta. Strategies to eliminate allergen exposure in the home and improve asthma control in these children may require tailoring for different racial groups.

Relationships among aeroallergen sensitization, peripheral blood eosinophils, and periostin in pediatric asthma development

BACKGROUND

Biomarkers, preferably noninvasive, that predict asthma inception in children are lacking.

OBJECTIVE

Little is known about biomarkers of type 2 inflammation in early life in relation to asthma inception. We evaluated aeroallergen sensitization, peripheral blood eosinophils, and serum periostin as potential biomarkers of asthma in children.

METHODS

Children enrolled in the Childhood Origins of ASThma study were followed prospectively from birth. Blood samples were collected at ages 2, 4, 6, and 11 years, and serum-specific IgE levels, blood eosionophil counts, and periostin levels were measured in 244 children. Relationships among these biomarkers, age, and asthma were assessed.

RESULTS

Serum periostin levels were approximately 2- to 3-fold higher in children than previously observed adult levels. Levels were highest at 2 years (145 ng/mL), and did not change significantly between 4 and 11 years (128 and 130 ng/mL). Age 2 year periostin level of 150 ng/mL or more predicted asthma at age 6 years (odds ratio [OR], 2.3; 95% CI, 1.3-4.4). Eosinophil count of 300 cells/μL or more and aeroallergen sensitization at age 2 years were each associated with increased risk of asthma at age 6 years (OR, 3.1; 95% CI, 1.7-6.0 and OR, 3.3; 95% CI, 1.7-6.3). Children with any 2 of the biomarkers had a significantly increased risk of developing asthma by school age (≥2 biomarkers vs none: OR, 6.6; 95% CI, 2.7-16.0).

CONCLUSIONS

Serum periostin levels are significantly higher in children than in adults, likely due to bone turnover, which impairs clinical utility in children. Early life aeroallergen sensitization and elevated blood eosinophils are robust predictors of asthma development. Children with evidence of activation of multiple pathways of type 2 inflammation in early life are at greatest risk for asthma development.

Prevalence of food sensitization and probable food allergy among adults in India: the EuroPrevall INCO study

BACKGROUND

Data are lacking regarding the prevalence of food sensitization and probable food allergy among general population in India. We report the prevalence of sensitization and probable food allergy to 24 common foods among adults from general population in Karnataka, South India.

METHODOLOGY

The study was conducted in two stages: a screening study and a case-control study. A total of 11 791 adults in age group 20-54 were randomly sampled from general population in South India and answered a screening questionnaire. A total of 588 subjects (236 cases and 352 controls) participated in the case-control study involving a detailed questionnaire and specific IgE estimation for 24 common foods.

RESULTS

A high level of sensitization (26.5%) was observed for most of the foods in the general population, higher than that observed among adults in Europe, except for those foods that cross-react with birch pollen. Most of the sensitization was observed in subjects who had total IgE above the median IgE level. A high level of cross-reactivity was observed among different pollens and foods and among foods. The prevalence of probable food allergy (self-reports of adverse symptoms after the consumption of food and specific IgE to the same food) was 1.2%, which was mainly accounted for cow's milk (0.5%) and apple (0.5%).

CONCLUSION

Very high levels of sensitization were observed for most foods, including those not commonly consumed in the general population. For the levels of sensitization, the prevalence of probable food allergy was low. This disassociation needs to be further explored in future studies.