Effects of pregnancy and lactation prebiotics supplementation on infant allergic disease: A randomized controlled trial.

BACKGROUND: Ingestion of prebiotics during pregnancy and lactation may have immunomodulatory benefits for the developing fetal and infant immune system and provide a potential dietary strategy to reduce the risk of allergic diseases. OBJECTIVE: We sought to determine whether maternal supplementation with dietary prebiotics reduces the risk of allergic outcomes in infants with hereditary risk. METHODS: We undertook a double-blind randomized controlled trial in which pregnant women were allocated to consume prebiotics (14.2 g daily of galacto-oligosaccharides and fructo-oligosaccharides in the ratio 9:1) or placebo (8.7 g daily of maltodextrin) powder from less than 21 weeks' gestation until 6 months postnatal during lactation. Eligible women had infants with a first-degree relative with a history of medically diagnosed allergic disease. The primary outcome was medically diagnosed infant eczema by age 1 year, and secondary outcomes included allergen sensitization, food allergy, and recurrent wheeze by age 1 year. RESULTS: A total of 652 women were randomized between June 2016 and November 2021 (329 in the prebiotics group and 323 in the placebo group). There was no significant difference between groups in the percentage of infants with medically diagnosed eczema by age 1 year (prebiotics 31.5% [103 of 327 infants] vs placebo 32.6% [105 of 322 infants]; adjusted relative risk, 0.98; 95% CI, 0.77-1.23; P = .84). Secondary outcomes and safety measures also did not significantly differ between groups. CONCLUSIONS: We found little evidence that maternal prebiotics supplementation during pregnancy and lactation reduces the risk of medically diagnosed infant eczema by age 1 year in infants who are at hereditary risk of allergic disease.

Increasing emergency department visits for anaphylaxis in very early childhood: A canary in the coal mine.

AIM: The incidence of anaphylaxis is increasing globally in tandem with changing environmental and lifestyle factors. There is very limited data on very early childhood presentations. We aim to assess changes in rates, characteristics and management of infant anaphylaxis in a paediatric ED over a 15-year period. METHODS: We conducted a retrospective study of children <2 years of age who presented with verified anaphylaxis comparing cases in years 2003-2007 with those in 2013-2017. Standardised information was collected on demographics, clinical presentation, management and triggers. RESULTS: Manually confirmed anaphylaxis rates in <2 year olds increased from 3.6 to 6.2 per 104 population (OR 1.7, 95% CI: 1.3-2.7; p < 0.001) with the greatest increase in <1 year olds. Anaphylaxis severity increased between 2003-2007 and 2013-2017 (OR 2.3, 95% CI: 1.2-4.3; p = 0.018). Failure to administer adrenaline was reduced in 2013-2017 (p = 0.007). Food was the leading anaphylaxis trigger (97.85%). CONCLUSION: This is the first study to suggest an increase in the incidence and severity of ED anaphylaxis presentations in children aged <2 years. Increased awareness of specific characteristics in this age group is required to facilitate timely recognition and optimal management. Further large-scale studies are warranted to understand underlying environmental drivers and find prevention strategies to reduce the burden of disease.

Penicillin allergy SHACK: Survey of hospital and community knowledge.

AIM: Penicillin allergy accounts for the majority of all reported adverse drug reactions in adults and children. Foregoing first-line antibiotic therapy due to penicillin allergy label is associated with an increased prevalence of infections by resistant organisms and longer hospitalisation. Clinician awareness of allergy assessment, referral indications, management of allergy and anaphylaxis is therefore vital but globally lacking. We aim to assess the knowledge of penicillin allergy, assessment and management in Western Australian health professionals. METHODS: An anonymous survey was distributed to pharmacists, nurses and physicians within Western Australian paediatric and adult Hospitals, Community and General Practice. RESULTS: In total, 487/611 were completed and included in the statistical analysis. Only 62% (301/487) of respondents routinely assessed for patient medication allergies. Of those who assessed allergy, 9% (28/301) of respondents met the Australian standards for allergy assessment. Only 22% (106/487) of participants correctly cited all indications for management with adrenaline in anaphylaxis to antibiotics and 67% (197/292) of physicians rarely or never referred to an allergy service. Paediatric clinicians had an increased understanding of allergy assessment and anaphylaxis management. Recent penicillin allergy education within a 5-year period led to significant improvements in allergy knowledge. CONCLUSION: Overall, knowledge, assessment and management of penicillin allergies among practitioners in Western Australia are currently inadequate in adults and paediatric clinicians to provide safe and effective clinical care. The implementation of a targeted education program for WA health professionals is urgently required and is expected to improve clinician knowledge and aid standardised penicillin assessment (de-labelling) practices.

In infants with sufficient vitamin D status at birth, vitamin D supplementation does not impact immune development.

BACKGROUND: Low vitamin D levels have been associated with allergic diseases. Vitamin D has potent immunomodulatory properties, but the mechanisms remain unclear. We have investigated the effect of oral vitamin D supplementation on circulating immune cell phenotypes in infants. METHOD: A double-blinded randomised controlled trial was conducted to investigate the effect of oral vitamin D supplementation (400 IU/d) on eczema and immune development. A subset of 78 infants was included in this analysis. Phenotypic analysis of immune cell subsets was performed using flow cytometry. RESULTS: Vitamin D supplementation resulted in median 25(OH)D levels of 80.5 vs 59.5 nmol/L in the placebo group at 3 months of age (P = .002) and 87.5 vs 77 nmol/L at 6 months of age (P = .08). We observed significant changes in immune cell composition from birth (cord blood) to 6 months of age. Vitamin D supplementation did not impact these changes, nor did immune cell composition correlate with plasma 25(OH)D levels. Through exploratory analysis, we identified possible associations with eczema development and increased abundance of naïve CD4- T cells at birth, as well as associations with basophils, iNKT and central memory CD4+ T cells, and altered expression patterns of IgE receptor (FcεR1) on monocytes and dendritic cells with eczema at 6 months. CONCLUSIONS: Vitamin D supplementation in infants who were vitamin D sufficient at birth did not affect developmental changes in immune cells during the first 6 months of life. However, immune cell profiles at birth and at 6 months of age were associated with early life eczema.

Direct infant UV light exposure is associated with eczema and immune development.

BACKGROUND: Suboptimal vitamin D levels during critical periods of immune development have emerged as an explanation for higher rates of allergic diseases associated with industrialization and residing at higher latitudes. OBJECTIVE: We sought to determine the effects of early postnatal vitamin D supplementation on infant eczema and immune development. METHODS: By using a double-blind randomized controlled trial, newborn infants were randomized to receive vitamin D supplementation (400 IU/d) or a placebo until 6 months of age. Some infants also wore personal UV dosimeters to measure direct UV light (290-380 nm) exposure. Infant vitamin D levels were measured at 3 and 6 months of age. Eczema, wheeze, and immune function outcomes were assessed at 6 months of age. RESULTS: At 3 (P < .01) and 6 (P = .02) months of age, vitamin D levels were greater for the vitamin D-supplemented group than the placebo group, but there was no difference in eczema incidence between groups. Infants with eczema were found to have had less UV light exposure (median, 555 Joules per square meter [J/m2; interquartile range, 322-1210 J/m2]) compared with those without eczema (median, 998 J/m2 [interquartile range, 676-1577 J/m2]; P = .02). UV light exposure was also inversely correlated with IL-2, GM-CSF, and eotaxin production to Toll-like receptor ligands. CONCLUSION: This study is the first to demonstrate an association between greater direct UV light exposures in early infancy with lower incidence of eczema and proinflammatory immune markers by 6 months of age. Our findings indicate that UV light exposure appears more beneficial than vitamin D supplementation as an allergy prevention strategy in early life.

The role of skin testing and extended antibiotic courses in assessment of children with penicillin allergy: An Australian experience.

AIM: To determine if skin testing (ST) in addition to extended oral provocation challenge (OPC) is necessary for beta-lactam allergy verification in an Australian paediatric population. METHODS: This was a retrospective study (176 children) that undertook assessments for beta-lactam allergy from 2006 to 2015 at a tertiary paediatric hospital. Patients either underwent direct OPC without ST or ST plus challenge if ST was negative. RESULTS: The analysis included children with a history of varying rash types/severity as well as angioedema and reported anaphylaxis. A direct OPC was undertaken in 73 children. Three children reacted with one anaphylaxis. A total of 103 children underwent ST, with 13 children (12.6%) reacting. Of the 90 who subsequently proceeded to OPC, 4 reacted. A total of 132 children were given an extended oral course of the culprit antibiotic, to which 6 children reacted. CONCLUSIONS: A direct OPC with the culprit drug in Australian children can be safely performed, avoiding resource-intensive and painful ST. Our data demonstrate that a prior history of anaphylaxis does not necessarily predict IgE-mediated allergy, as detected by positive immediate ST or reactions to oral challenge. Such history should not detract from efforts to assess these children for antibiotic allergy. We suggest that extended courses of at least 5 days are important in paediatric antibiotic de-labelling as six children (4.5% of those who were prescribed the extended course) reacted in our study and even developed symptoms late in the extended course, from days 2 to 6.

Developing Primary Intervention Strategies to Prevent Allergic Disease.

Allergic diseases are a major cause of morbidity in the developed world, now affecting up to 40 % of the population with no evidence that this is abating. If anything, the prevalence of early onset allergic diseases such as eczema and food allergy appears to be still increasing. This is almost certainly due to the changing modern environment and lifestyle factors, acting to promote immune dysfunction through early perturbations in immune maturation, immune tolerance and regulation. This early propensity to inflammation may also have implications for the rising risk of other inflammatory non-communicable diseases (NCDs) later in life. Identifying risk factors and pathways for preventing early onset immune disease like allergy is likely to have benefits for many aspects of human health, particularly as many NCDs share similar risk factors. This review focuses on recent advances in primary intervention strategies for promoting early immune health and preventing allergic disease, highlighting the current evidence-based guidelines where applicable and areas requiring further investigation.

Nutritional approaches for the primary prevention of allergic disease: An update.

The dramatic rise in early childhood allergic diseases indicates the specific vulnerability of the immune system to early life environmental changes. Dietary changes are at the centre of lifestyle changes that underpin many modern inflammatory and metabolic diseases, and therefore are an essential element of prevention strategies. Although modern dietary changes are complex and involve changing patterns of many nutrients, there is also an interest in the early life effects of specific nutrients including polyunsaturated fatty acids, oligosaccharides (soluble fibre), antioxidants, folate and other vitamins that have documented effects on immune function as well as metabolism. A better understanding of nutritional programming of immune health, nutritional epigenetics and the biological processes sensitive to nutritional exposures in early life may lead to dietary strategies that provide more tolerogenic conditions during early immune programming and reduce the burden of many inflammatory diseases, not just allergy.

Hot topics in paediatric immunology: IgE-mediated food allergy and allergic rhinitis.

BACKGROUND: The epidemic of allergic disease is a major public health crisis. The greatest burden of allergies is in childhood, when rapidly rising rates of disease are also most evident. General practitioners (GP) have a key role in recognising and addressing aller-gy-related problems and identifying whether a child requires referral to a paediatric allergist. OBJECTIVE: This article focuses on IgE-mediated food allergies and allergic rhinitis, the most commonly seen conditions in paediatric im-munology. We will discuss prevention, diagnosis, management and treatment strategies. DISCUSSION: Currently there is no cure for food allergy. Oral tolerance induction continues to be a significant focus of research. All children with a possible food allergy should be referred to an allergist for further testing and advice. Children who develop allergic rhinitis need a regular review by their GP. Immunotherapy should be discussed early in the disease process and needs to be com-menced by an allergist.

Comparing Skin and Serum Testing to Direct Challenge Outcomes in Children With ß-Lactam Allergies.

BACKGROUND: There is a scarcity of prospective studies investigating the relative roles of skin prick and intradermal testing, serum specific IgE, and extended oral challenges in diagnosing children with reported ß-lactam allergies. OBJECTIVE: To determine the sensitivity and specificity of skin testing and serum specific IgE in children with ß-lactam allergies, with immediate and nonimmediate historic reactions. METHODS: Four hundred children with parent-reported ß-lactam allergies were recruited into an open-label prospective study. Detailed allergy histories were collected. Those with medically observed and documented histories of anaphylaxis, requiring epinephrine, or severe cutaneous adverse reactions were excluded. In total, 380 children underwent all testing modalities and a direct provocation test. Each child was followed up for a minimum of 3 years. RESULTS: True allergy in children was uncommon; 8.3% reacted to the direct provocation challenge or the 5-day extended oral provocation challenge. Children reporting cephalosporin allergy or a reaction within 1 year were more likely to react to direct provocation testing. The sensitivity, specificity, and positive predictive value of skin testing were 12.5%, 98.8%, and 20.0% for direct challenge outcomes, 4.76%, 99.0%, and 25.0% for extended challenge outcomes, and 6.9%, 99.0%, and 40.0% for both challenges combined, respectively. Follow-up investigations revealed that 5.7% of children had a mild repeat reaction and 2.7% continued to avoid the culprit despite successful delabeling. The relabeling rate for children readmitted to hospital was 15%, with the relabeing being unfounded. CONCLUSIONS: Genuine ß-lactam allergies were rare, with over 90% of children effectively delabeled. Skin and serum specific IgE testing did not aid the diagnosis of ß-lactam antibiotic allergy in children, regardless of medical history. Extended oral challenges proved valuable in confirming allergies and boosted parental confidence.

Symptomatic viral infection is associated with impaired response to treatment in children with acute asthma.

OBJECTIVE: To examine the influence of viral respiratory infection (VRI) on treatment response in acute asthma in children. STUDY DESIGN: A total of 218 children (mean age, 6.6 years) with acute asthma were recruited. Symptoms were recorded, an asthma severity score was determined, and whenever possible, a per-nasal aspirate was obtained for detection of viruses. Each child's response to inhaled ß(2)-agonists was assessed after 6, 12, and 24 hours. RESULTS: The 168 children with VRI symptoms received more treatment with inhaled ß(2)-agonists after 6 hours (P = .010), 12 hours (P = .002), and 24 hours (P = .0005) compared with the 50 children without such symptoms. Asthma severity did not differ between the 2 groups. A per-nasal aspirate was obtained from 77% of the children. The most frequently identified virus was rhinovirus (61.4%). Among children with symptoms of a VRI, those with rhinovirus had an impaired response to ß(2)-agonists at 6 hours (P = .032). CONCLUSION: Children with acute asthma and symptoms of VRI respond less effectively to ß(2)-agonists after 6, 12, or 24 hours and thus may benefit from more intense therapy and monitoring.

Pre- and Postnatal Vitamin D Status and Allergy Outcomes in Early Childhood.

The dramatic increase in the prevalence of allergic disease in recent decades reflects environmental and behavioural changes that have altered patterns of early immune development. The very early onset of allergic diseases points to the specific vulnerability of the developing immune system to environmental changes and the development of primary intervention strategies is crucial to address this unparalleled burden. Vitamin D is known to have immunomodulatory functions. While allergic disease is multifactorial, associations with reduced sunlight exposure have led to the hypothesis that suboptimal vitamin D levels during critical early periods may be one possible explanation. Interventions to improve vitamin D status, especially in early life, may be the key to allergic disease prevention.

Acute management of anaphylaxis in pregnancy.

BACKGROUND: Anaphylaxis in pregnancy is rare but can potentially be associated with significant morbidity and mortality for the mother, fetus and neonate. With appropriate and timely management, even severe anaphylaxis can be managed with excellent maternal and fetal outcomes. OBJECTIVE: The aim of this article is to provide an illustrative case and highlight current recommendations for diagnosis and management of acute maternal anaphylaxis, which have recently been reviewed and developed into a guideline by the Australasian Society of Clinical Immunology and Allergy. DISCUSSION: An understanding of management of anaphylaxis in pregnancy is essential knowledge in the general practice setting. The recommended dosage and administration of adrenaline (epinephrine) for anaphylaxis is the same in pregnant and non-pregnant patients: 0.5 mg adrenaline intramuscularly in the mid-outer thigh (or dose of 0.01 mg/kg if <50 kg). The use of adrenaline in maternal anaphylaxis is supported by various international guidelines.

The Influence of Sunlight Exposure and Sun Protecting Behaviours on Allergic Outcomes in Early Childhood.

The dramatic rise in allergic disease has occurred in tandem with recent environmental changes and increasing indoor lifestyle culture. While multifactorial, one consistent allergy risk factor has been reduced sunlight exposure. However, vitamin D supplementation studies have been disappointing in preventing allergy, raising possible independent effects of ultraviolet (UV) light exposure. The aim of this study was to examine whether UV light exposure influences the development of allergic disease in early childhood. Direct sunlight exposure (290-380 nm) in early infancy was measured via UV dosimeters. Outdoor exposure, sun protective behaviours, and allergy outcomes were assessed over the first 2.5 years of life with clinical assessment appointments at 3, 6, 12 and 30 months of age. Children with eczema had less (p = 0.038) direct UV light exposure between 0-3 months of age (median (IQR) 747 (473-1439) J/m2) than children without eczema (median (IQR) 1204 (1717-1843) J/m2); and less outdoor exposure time (7 min/day) between 11 a.m. and 3 p.m. compared to children without eczema (20 min/day, p = 0.011). These associations were seen independent of vitamin D status, and after adjusting for other potential confounders. Whilst we could not find any associations between direct UV light exposure and other allergic disease outcomes, exposure to UV light appears to be beneficial in reducing the risk of eczema development in early childhood. Further research is required to determine optimal levels of UV light exposure while balancing the potential risks.

In "High-Risk" Infants with Sufficient Vitamin D Status at Birth, Infant Vitamin D Supplementation Had No Effect on Allergy Outcomes: A Randomized Controlled Trial.

Lower vitamin D status at birth and during infancy has been associated with increased incidence of eczema and food allergies. The aim of this study was to investigate the effect of early infancy vitamin D supplementation on allergic disease outcomes in infants at "hereditary risk" of allergic disease, but who had sufficient vitamin D levels at birth. Here, we report the early childhood follow-up to 2.5 years of age of "high-risk" infants who participated in a double-blinded, randomized controlled trial. For inclusion in this trial, late gestation (36-40 weeks) maternal 25-hydroxyvitamin D levels needed to be ≥50 nmol/L. Infants were randomized to either oral vitamin D supplementation of 400 IU/day (n = 97) or a placebo (n = 98) for the first six months of life. Vitamin D levels and allergic disease outcomes were followed up. There were no statistically significant differences in incidence of any medically diagnosed allergic disease outcomes or allergen sensitization rates between the vitamin D-supplemented and placebo groups at either 1 year or at 2.5 years of age. In conclusion, for "allergy high-risk" infants who had sufficient vitamin D status at birth, early infancy oral vitamin D supplementation does not appear to reduce the development of early childhood allergic disease.