The optimal diagnostic workup for children with suspected food allergy

Diagnostic therapeutic care pathway for pediatric food allergies and intolerances in Italy: a joint position paper by the Italian Society for Pediatric Gastroenterology Hepatology and Nutrition (SIGENP) and the Italian Society for Pediatric Allergy and Immunology (SIAIP)

Epidemiologic data suggest an increased prevalence of pediatric food allergies and intolerances (FAIs) during the last decades. This changing scenario has led to an increase in the overall healthcare costs, due to a growing demand for diagnostic and treatment services. There is the need to establish Evidence-based practices for diagnostic and therapeutic intervention that could  be adopted in the context of public health policies for FAIs are needed.

This joint position paper has been prepared by a group of experts in pediatric gastroenterology, allergy and nutrition from the Italian Society for Pediatric Gastroenterology Hepatology and Nutrition (SIGENP) and the Italian Society for Pediatric Allergy and Immunology (SIAIP). The paper is focused on the Diagnostic Therapeutic Care Pathway (DTCP) for pediatric FAIs in Italy.

Does faecal calprotectin differentiate between inflammatory bowel disease colitis and non-inflammatory bowel disease colitides?

Introduction

Chronic colitis is a major problem worldwide with high morbidity. Causes of chronic colitis are heterogeneous. A cut-off level of faecal calprotectin to predict inflammatory bowel disease (IBD) as a cause of chronic colitis is lacking.

Aim

To study the level of faecal calprotectin in different causes of colitis and to measure the cut-off level to differentiate between IBD and non-IBD colitides.

Material and methods

This prospective study was conducted from June 2018 to May 2019. The study included all patients aged 2 months up to 18 years who were confirmed to have chronic colitis endoscopically and histopathologically attending the Gastroenterology Clinic at Alexandria University Children’s Hospital. Faecal calprotectin level was measured.

Results

We included 110 patients. Allergic colitis was the commonest cause followed by IBD followed by infectious colitis (50.9%, 38.1% and 6.3% respectively). Faecal calprotectin above 744 µg/g could predict IBD as a cause of chronic colitis with 86.8% specificity and 66.7% sensitivity. Significant elevation of faecal calprotectin was detected in IBD patients. Faecal calprotectin was significantly correlated with C-reactive protein level and erythrocyte sedimentation rate.

Conclusions

Faecal calprotectin could predict the cause of colitis and could aid the paediatrician for early referral of patients with chronic colitis.

Comel-Netherton syndrome: A local skin barrier defect in the absence of an underlying systemic immunodeficiency

Background

Comel‐Netherton syndrome (NS) is a rare autosomal disease, characterized by severe skin disease, hair shaft defects, atopic diathesis, and increased susceptibility for skin infections. Since patients with NS suffer from recurrent infections, it has been hypothesized that an underlying immunodeficiency attributes to this. Here, we studied clinical and immunological characteristics of the cohort of NS patients in the Netherlands in order to identify whether potential immunodeficiencies result in the increased risk of infectious complications.

Methods

Phenotypes were scored for severity of skin condition, specific hair shaft defects, atopy, and recurrent infections. Patients’ blood samples were collected for quantification of serum immunoglobulin (Ig) levels, specific antibodies against Streptococcuspneumoniae, and allergen‐specific IgE, as well as detailed immunophenotyping of blood leukocyte and lymphocyte subsets by flow cytometry.

Results

A total of 14 patients were included with age range 3‐46 years and varying degrees of skin involvement. All patients presented with atopic symptoms (food allergy, n = 13; hay fever, n = 10; asthma, n = 7). Recurrent skin infections were common, particularly in childhood (n = 12). Low levels of specific antibodies against S pneumoniae were found in 10 of 11 evaluated patients. Detailed immunological analysis was performed on 9 adult patients. Absolute numbers of lymphocyte subsets and serum immunoglobulin levels were all within normal ranges.

Conclusion

Multidisciplinary evaluation of our national cohort showed no evidence for a severe, clinically relevant systemic immunodeficiency. Therefore, we conclude that in Dutch NS patients the increased risk of infections most likely results from the skin barrier disruption and that increased allergen penetration predisposes to allergic sensitization.

Nutritional control of immunity: Balancing the metabolic requirements with an appropriate immune function

The immune system is a highly integrated network of cells sensitive to a number of environmental factors. Interestingly, recent years have seen a dramatic increase in our understanding of how diet makes a crucial contribution to human health, affecting the immune system, secretion of adipocytokines and metabolic pathways. Recent experimental evidence indicates that diet and its components are able to profoundly influence immune responses, thus affecting the development of inflammatory and autoimmune diseases. This review aims to discuss some of the main topics concerning the impact of nutrients and their relative composition on immune cell development and function that may be particularly important for regulating the balance between inflammatory and tolerogenic processes. We also highlight the effects of diet on commensal bacteria and how changes in the composition of the microbiota alter intestinal and systemic immune homeostasis. Finally, we summarize the effects of dietary compounds on epigenetic mechanisms involved in the regulation of several immune related genes.

Lactobacillus rhamnosus GG-supplemented formula expands butyrate-producing bacterial strains in food allergic infants

Dietary intervention with extensively hydrolyzed casein formula supplemented with Lactobacillus rhamnosus GG (EHCF+LGG) accelerates tolerance acquisition in infants with cow's milk allergy (CMA). We examined whether this effect is attributable, at least in part, to an influence on the gut microbiota. Fecal samples from healthy controls (n=20) and from CMA infants (n=19) before and after treatment with EHCF with (n=12) and without (n=7) supplementation with LGG were compared by 16S rRNA-based operational taxonomic unit clustering and oligotyping. Differential feature selection and generalized linear model fitting revealed that the CMA infants have a diverse gut microbial community structure dominated by Lachnospiraceae (20.5±9.7%) and Ruminococcaceae (16.2±9.1%). Blautia, Roseburia and Coprococcus were significantly enriched following treatment with EHCF and LGG, but only one genus, Oscillospira, was significantly different between infants that became tolerant and those that remained allergic. However, most tolerant infants showed a significant increase in fecal butyrate levels, and those taxa that were significantly enriched in these samples, Blautia and Roseburia, exhibited specific strain-level demarcations between tolerant and allergic infants. Our data suggest that EHCF+LGG promotes tolerance in infants with CMA, in part, by influencing the strain-level bacterial community structure of the infant gut.

Update in pediatric anaphylaxis: a systematic review

Anaphylaxis is common in children and has many differences across age groups. A systematic review of the literature from the past 5 years was conducted with the goal of updating the pediatrician. Food is the most common trigger in children, but insect venom and drugs are other typical causes. Clinical diagnostic criteria include dermatological, respiratory, cardiovascular, and gastrointestinal manifestations. A biphasic reaction is seen in some, with recurrence usually within 8 hours of the initial episode. Epinephrine is the drug of choice for acute reactions and the only medication shown to be lifesaving when administered promptly, but it is underutilized. Patients should have ready access to ≥2 doses of an epinephrine autoinjector, with thorough training regarding correct use of a given device and an emergency action plan. Management of anaphylaxis in schools presents distinct challenges. Pediatricians are in a unique position to assess and treat these patients chronically.

Factors associated with infantile eczema in Hangzhou, China

The removal of aggravating factors is important to reduce the severity of infantile eczema, but there are few studies on the assessment and identification of the aggravating factors in infantile eczema. Parents of children with infantile eczema ages 1 to 10 months (N = 250) were recruited. Parents were required to complete a questionnaire. Two hundred forty-two (96.8%) children had skin dryness, 80% bathed with soap or shower gel, 82% often perspired, 84.8% wore tight-fitting clothes, 80.8% dressed in five layers of thick clothing, 85.6% were in contact with wool or feathers, and 59.2% were exposed to sunlight (>20 minutes/day). Eczema severity was greater after vaccination in 20%. Two hundred thirty-five mothers avoided eating potential food allergens (e.g., milk, egg whites, and fish), but this failed to improve the severity of symptoms in 93.6% of the children. Thirty patients had Neocate as a substitute for cow's milk, which resulted in symptom severity improvement in 10%. Thirty children were given food allergens, which exacerbated symptoms in 13.3%. One hundred twenty-eight (51.2%) of the children were treated with corticosteroid ointment; 62.5% had the ointment applied for only 2 to 3 days, and 6.2% had the corticosteroid ointment applied to weeping lesions. The vast majority of parents did not know about the aggravating factors for infantile eczema. The results demonstrated a strong need for educational programs to help parents understand and control infantile eczema.

Chronic diarrhoea in children

Chronic diarrhoea in children shows an age related spectrum. In infants and young children a major role is related to persistent intestinal infections, intolerance to specific nutrients such as cow's milk protein, and toddler's diarrhoea. In older children and adolescents, inflammatory bowel diseases are strongly increasing and nonspecific diarrhoea is also frequent. Coeliac disease is a major cause of diarrhoea throughout childhood. In neonates, congenital diarrhoea is a rare but severe syndrome that includes several highly complex diseases. In children, diagnosis should be based on noninvasive techniques. Endoscopy should be decided based on clinical criteria, but also driven by noninvasive tests to assess the digestive absorptive functions and intestinal inflammation. A stepwise approach may reduce the need of endoscopy, also in the light of its relatively limited diagnostic yield compared to adult patients. Treatment of chronic diarrhoea in children is also substantially different from what is generally done in adults and includes a major role for nutritional interventions. Therefore chronic diarrhoea in children is a complex age-specific disorder that requires an age-specific management that is in many aspects distinct from that in adults.