A Prospective Assessment of Clinical Characteristics and Responses to Dietary Elimination in Food Protein-Induced Allergic Proctocolitis

A nationwide survey of non-IgE-mediated gastrointestinal food allergies in neonates and infants

BACKGROUND

Non-IgE-mediated gastrointestinal food allergies (non-IgE-GIFAs) seem to be increasing rapidly worldwide. However, nationwide studies have been limited to food-protein-induced enterocolitis (FPIES) and food-protein-induced allergic proctocolitis (FPIAP), with little attention to other non-IgE-GIFA subgroups. The aim of this study was to elucidate the clinical features of all patients with non-IgE-GIFAs, not just certain subgroups.

METHODS

We conducted a nationwide cross-sectional survey of non-IgE-GIFAs in Japan from April 2015 through March 2016. A questionnaire was sent to hospitals and clinics throughout Japan. The questionnaire asked about the number of physician-diagnosed non-IgE-GIFA patients, the status of fulfillment of the diagnostic criteria, tentative classification into 4 clusters based on the initial symptoms, the day of onset after birth, complications, and the suspected offending food(s).

RESULTS

The response rate to that questionnaire was 67.6% from hospitals and 47.4% from clinics. Analyses were conducted about "diagnosis-probable" patient cohort (n = 402) and the "diagnosis-confirmed" patients (n = 80). In half of the reported non-IgE-GIFA patients, onset occurred in the neonatal period. The patients were evenly distributed among 4 non-IgE-GIFA clusters. In Cluster 1, with symptoms of vomiting and bloody stool, the onset showed a median of 7 days after birth, which was the earliest among the clusters. Cow's milk was the most common causative food.

CONCLUSIONS

In half of the patients, the onset of non-IgE-GIFAs was in the neonatal period. This highlights the importance of studying the pathogenesis in the fetal and neonatal periods.

To Diet or Not to Diet This Is the Question in Food-Protein-Induced Allergic Proctocolitis (FPIAP)-A Comprehensive Review of Current Recommendations

Food-protein-induced allergic proctocolitis (FPIAP) is an increasingly reported transient and benign form of colitis that occurs commonly in the first weeks of life in healthy breastfed or formula-fed infants. Distal colon mucosal inflammation is caused by a non-IgE immune reaction to food allergens, more commonly to cow's milk protein. Rectal bleeding possibly associated with mucus and loose stools is the clinical hallmark of FPIAP. To date, no specific biomarker is available, and investigations are reserved for severe cases. Disappearance of blood in the stool may occur within days or weeks from starting the maternal or infant elimination diet, and tolerance to the food allergen is typically acquired before one year of life in most patients. In some infants, no relapse of bleeding occurs when the presumed offending food is reassumed after a few weeks of the elimination diet. Many guidelines and expert consensus on cow's milk allergy have recently been published. However, the role of diet is still debated, and recommendations on the appropriateness and duration of allergen elimination in FPIAP are heterogeneous. This review summarizes and compares the different proposed nutritional management of infants suffering from FPIAP, highlighting the pros and cons according to the most recent literature data.

An ESPGHAN Position Paper on the Diagnosis, Management, and Prevention of Cow's Milk Allergy

A previous guideline on cow's milk allergy (CMA) developed by the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) was published in 2012. This position paper provides an update on the diagnosis, treatment, and prevention of CMA with focus on gastrointestinal manifestations. All systematic reviews and meta-analyses regarding prevalence, pathophysiology, symptoms, and diagnosis of CMA published after the previous ESPGHAN document were considered. Medline was searched from inception until May 2022 for topics that were not covered in the previous document. After reaching consensus on the manuscript, statements were formulated and voted on each of them with a score between 0 and 9. A score of ≥6 was arbitrarily considered as agreement. Available evidence on the role of dietary practice in the prevention, diagnosis, and management of CMA was updated and recommendations formulated. CMA in exclusively breastfed infants exists, but is uncommon and suffers from over-diagnosis. CMA is also over-diagnosed in formula and mixed fed infants. Changes in stool characteristics, feeding aversion, or occasional spots of blood in stool are common and in general should not be considered as diagnostic of CMA, irrespective of preceding consumption of cow's milk. Over-diagnosis of CMA occurs much more frequently than under-diagnosis; both have potentially harmful consequences. Therefore, the necessity of a challenge test after a short diagnostic elimination diet of 2-4 weeks is recommended as the cornerstone of the diagnosis. This position paper contains sections on nutrition, growth, cost, and quality of life.

Diagnostic and Management Strategies of Food Protein-Induced Enterocolitis Syndrome: Current Perspectives

Food protein-induced enterocolitis syndrome (FPIES) is a form of non-IgE mediated food allergy that presents with delayed gastrointestinal symptoms after ingestion of the trigger food. The data regarding FPIES are sparse, despite being recognized as a distinct clinical entity. This narrative review presents the characteristics of this disorder in the pediatric population, as well-standard diagnostic and management protocols. FPIES can be classified into acute and chronic subtypes, and some cases may develop into an IgE-mediated allergy. Given that skin prick tests and specific IgE levels are negative in the majority of cases, diagnosis relies on clinical history and oral food challenges. Management involves elimination diets, assessment of tolerance through oral food challenges, and rehydration in the event of a reaction. Future research should focus on improving diagnostic methods, illustrating underlying pathogenesis and biomarkers, and assessing long-term natural history. Increased knowledge and awareness for FPIES are required.

Allergic Proctocolitis: Literature Review and Proposal of a Diagnostic-Therapeutic Algorithm

Allergic proctocolitis (AP) is a benign condition, frequent in childhood, that is classified as a non-IgE-mediated food allergy. The prevalence is unknown; however, its frequency appears to be increasing, especially in exclusively breastfed infants. Clinical manifestations typically begin in the first few months of life with the appearance of bright red blood (hematochezia), with or without mucus, in the stool of apparently healthy, thriving infants. Most cases of AP are caused by cow's milk proteins; however, other allergens, such as soy, egg, corn, and wheat, may be potential triggers. Diagnosis is based on the patient's clinical history and on the resolution of signs and symptoms with the elimination of the suspected food antigen from the diet and their reappearance when the food is reintroduced into the diet. The treatment of AP is based on an elimination diet of the trigger food, with resolution of the symptoms within 72-96 h from the beginning of the diet. The prognosis of AP is good; it is a self-limiting condition, because most children can tolerate the trigger food within one year of life, with an excellent long-term prognosis. The purpose of this review is to provide an update on the current knowledge and recommendations in epidemiological, diagnostic, and therapeutic terms to the pediatricians, allergists, and gastroenterologists who may find themselves managing a patient with AP.

Dietary Factors May Delay Tolerance Acquisition in Food Protein-Induced Allergic Proctocolitis

BACKGROUND

Dietary and environmental factors may influence tolerance acquisition in food protein-induced allergic proctocolitis (FPIAP). This retrospective observational study explored the role of maternal diet during pregnancy and breastfeeding in tolerance acquisition in infantile FPIAP.

METHODS

Breastfed infants with FPIAP from six diverse regions in Greece were divided into two groups, based on development of tolerance to the trigger food: Group A (n = 43), before, and Group B (n = 53), after, the 6th month of age. Maternal diet during pregnancy and breastfeeding was elicited using the Mediterranean Diet Score Questionnaire and the Mediterranean Oriented Culture Specific Semi-Quantitative Food Frequency Questionnaire.

RESULTS

Mean age at diagnosis of FPIAP (1.5 months) and weaning (5.5 months) were the same in both groups. The main trigger was cow's milk. Group A received infant milk formula earlier than Group B. Group B had a higher incidence of asthma/wheeze, siblings with milk allergy, maternal smoking and rural residence. On multivariate analysis, earlier resolution of FPIAP was associated with higher maternal education and with salt intake and consumption of goat/sheep cheese during pregnancy and olive oil during breastfeeding. Consumption of multivitamins during pregnancy and meat, winter fruits, green vegetables, butter, salt, "ready-to-eat" meals and pastries during breastfeeding were correlated with longer duration of symptoms.

CONCLUSIONS

Mothers of children with FPIAP to cow's milk protein can be advised to eat more yogurt, cheese and olive oil during subsequent pregnancies, and avoid multivitamins, grilled food, "ready-to-eat" meals, pastries, meat and alcohol during breastfeeding, to reduce the duration of FPIAP presenting in future infants.

Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) Guidelines update - III - Cow's milk allergens and mechanisms triggering immune activation

Background

The immunopathogenesis of cow's milk protein allergy (CMPA) is based on different mechanisms related to immune recognition of protein epitopes, which are affected by industrial processing.

Purpose

The purpose of this WAO DRACMA paper is to: (i) give a comprehensive overview of milk protein allergens, (ii) to review their immunogenicity and allergenicity in the context of industrial processing, and (iii) to review the milk-related immune mechanisms triggering IgE-mediated immediate type hypersensitivity reactions, mixed reactions and non-IgE mediated hypersensitivities.

Results

The main cow’s milk allergens – α-lactalbumin, β-lactoglobulin, serum albumin, caseins, bovine serum albumins, and others – may determine allergic reactions through a range of mechanisms. All marketed milk and milk products have undergone industrial processing that involves heating, filtration, and defatting. Milk processing results in structural changes of immunomodulatory proteins, leads to a loss of lipophilic compounds in the matrix, and hence to a higher allergenicity of industrially processed milk products. Thereby, the tolerogenic capacity of raw farm milk, associated with the whey proteins α-lactalbumin and β-lactoglobulin and their lipophilic ligands, is lost.

Conclusion

The spectrum of immunopathogenic mechanisms underlying cow's milk allergy (CMA) is wide. Unprocessed, fresh cow's milk, like human breast milk, contains various tolerogenic factors that are impaired by industrial processing. Further studies focusing on the immunological consequences of milk processing are warranted to understand on a molecular basis to what extent processing procedures make single milk compounds into allergens.