Food allergy is increasing in prevalence, affecting up to 10% of children in developed countries. Food allergy can significantly affect the quality of life and well‐being of patients and their families; therefore, an accurate diagnosis is of extreme importance. Some food allergies can spontaneously resolve in 50%‐60% of cow’s milk and egg‐allergic, 20% of peanut‐allergic and 9% of tree nut‐allergic children by school age. For that reason, food‐allergic status should be monitored over time to determine when to reintroduce the food back into the child’s diet. The gold‐standard to confirm the diagnosis and the resolution of food allergy is an oral food challenge; however, this involves the risk of causing an acute‐allergic reaction and requires clinical experience and resources to treat allergic reactions of any degree of severity. In the clinical setting, biomarkers have been used and validated to enable an accurate diagnosis when combined with the clinical history, deferring the oral food challenge, whenever possible. In this review, we cover the tools available to support the diagnosis of food allergies and to predict food allergy resolution over time. We review the latest evidence on different testing modalities and how effective they are in guiding clinical decision making in practice. We also evaluate predictive test cut‐offs for the more common food allergens to try and provide guidance on when challenges might be most successful in determining oral tolerance in children.

The impact on health related quality of life (HRQL) has been well studied in children with Immunoglobulin E (IgE)-mediated food allergy. However limited data exists on related quality of life (QOL) of families who have a child suffering from food protein induced non-IgE mediated gastrointestinal allergies. We aimed to establish the QOL of families with children at the beginning of following an elimination diet for non-IgE mediated gastrointestinal food allergies. A prospective, observational study was performed. Parents of children aged 4 weeks–16 years who improved after 4–8 weeks of following an elimination diet for suspected non-IgE mediated allergies were included. The Family Impact Module (FIM) of the Pediatric Quality of Life (PedsQL™) was used and we compared our data to two historical cohorts: one with sickle cell disease and another with intestinal failure. One hundred and twenty three children with a median age of 20 months were included (84 boys). The total FIM Score was 57.43 (SD 22.27) and particularly low for daily activities and worry. Factors that impacted significantly included age (p < 0.0001), number of foods excluded (p = 0.008), symptom severity (p = 0.041) and chronic nasal congestion (p = 0.012). Children with non-IgE mediated food allergies had worse scores in all domains (p < 0.0001) compared to sickle cell disease and worse physical (p = 0.04), emotional (p = 0.04) and worry (p = 0.01) domains compared to intestinal failure. This study found that parent QOL and family functioning was worse in those families who had a child on an elimination diet for non-IgE mediated allergies compared to those with sickle cell disease and intestinal failure, highlighting the impact this disease has on families.

The choice of infant formula is thought to play an important role on gastric emptying (GE) in a variety of gastrointestinal disorders. It is known that many ingredients impact on GE, including the type of protein and level of hydrolysis. In clinical practice, feeds are often recommended due to putative improved GE related to the type of protein and level of hydrolysis, however whether this is scientifically justified still needs to be established. A systematic review comparing the impact of protein type and hydrolysis on GE in children was therefore performed. The Patient, Intervention, Comparison and Outcome system was used. A structured literature search was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, searching PubMed, Cochrane databases and Google Scholar from 1990 to 2014. We only included articles published in full text English language using specific search terms, including both scintigraphy and C13-octanoic acid breath test. We identified 126 publications of which 20 were eligible for inclusion but only 8 were included. Studies reviewed GE in both healthy children as well as those with neurodevelopmental delay and reflux. Two studies investigating GE of breast milk versus formula indicated a faster GE for breast milk. Four studies found that feeds containing whole whey in varying amounts emptied faster than predominant whole casein feeds and one study found no difference in GE. Five studies investigated a mix of whole versus hydrolysed protein and found conflicting results related to study population and hydrolysis. Breast milk has a faster GE than formula milk. Although there seems to be a trend towards whey feeds emptying faster, different methodologies, feed compositions and patient groups makes it difficult to draw firm conclusions. Future studies should be performed with comparable feeds in populations where increased GE may be of clinical benefit.

There is no data on the prevalence of vitamin D deficiency in children with non-immunoglobulin-E (IgE) mediated gastrointestinal food allergy. The aims of our study were to understand the prevalence of vitamin D insufficiency and deficiency in children with non-IgE mediated gastrointestinal food allergy and identify predisposing factors. This was a retrospective study which looked at data from Great Ormond Street Hospital from January 2002 to September 2015. Children 0–18 years old with a confirmed diagnosis of non-IgE mediated gastrointestinal food allergy who had a vitamin D level measured during the course of their disease were included. Low vitamin D levels were defined as <50 nmol/L; insufficient levels were defined as 25–50 nmol/L and deficient levels as <25 nmol/L. Patient characteristics and clinical factors were also recorded. Ninety-two patients met the study criteria; 49% were female and median age was 10 years 2 months [IQR: 4 years 8 months to 13 years 7 months]. Of the cohort, 26% (24/92) had low vitamin D levels; 16% had insufficient vitamin D levels and 10% had vitamin D deficiency. Gender (p = 0.043) and age (p = 0.035) were significantly associated with low vitamin D levels. Twelve percent of children who were on an amino acid formula (AAF) had low vitamin D compared to 31% of children who were not (p = 0.06). No other clinical factors were found to be significantly associated with low vitamin D levels. Children with non-IgE mediated gastrointestinal food allergy are at risk of vitamin D insufficiency and deficiency. Further prospective studies need to be performed in all children with non-IgE mediated gastrointestinal food allergies. The study was registered with the GOSH Research & Development department as a retrospective case note review. The Health Research Authority confirmed that NHS Research and Ethics Committee approval was not required; thus there is no trial registration number.

Background: Various biomarkers are used to define peanut allergy (PA). We aimed to observe changes in PA resolution and persistence over time comparing biomarkers in PA and peanut sensitised but tolerant (PS) children in a population‐based cohort. Methods: Participants were recruited from the EAT and EAT‐On studies, conducted across England and Wales, and were exclusively breastfeed babies recruited at 3 months old and followed up until 7–12 years old. Clinical characteristics, skin prick test (SPT), sIgE to peanut and peanut components and mast cell activation tests (MAT) were assessed at 12 months, 36 months and 7–12 years. PA status was determined at the 7–12 year time point. Results: The prevalence of PA was 2.1% at 7–12 years. Between 3 and 7–12 year, two children developed PA and one outgrew PA. PA children had larger SPT, higher peanut‐sIgE, Ara h 2‐sIgE and MAT (all p < .001) compared to PS children from 12 months onwards. SPT, peanut‐sIgE, Ara h 2‐sIgE and MAT between children with persistent PA, new PA, outgrown PA and PS were statistically significant from 12 months onwards ( p < .001). Those with persistent PA had SPT, peanut‐sIgE and Ara h 2‐sIgE that increased over time and MAT which was highest at 36 months. New PA children had increased SPT and peanut‐sIgE from 36 months to 7–12 years, but MAT remained low. PS children had low biomarkers across time. Conclusions: In this cohort, few children outgrow or develop new PA between 36 months and 7–12 years. Children with persistent PA have raised SPT, peanut‐sIgE, Ara h 2‐sIgE and MAT evident from infancy that consistently increase over time.