Fruit-induced FPIES masquerading as hereditary fructose intolerance

Food protein-induced enterocolitis syndrome in an infant triggered by prunes

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE mediated food allergy that has a cumulative incidence of 0.015 to 0.7% in infants [1]. The most common allergens causing FPIES reactions include cow's milk, followed by soy, grains, and rice [1, 3]. Increasing clinical awareness of FPIES has resulted in the expansion of emerging triggers of FPIES, including fruit antigens.

CASE PRESENTATION

We describe an infant diagnosed with FPIES to prune.

CONCLUSION

Fruit allergens are an emerging group of triggers for FPIES, both in their fresh and dried forms. To our knowledge, this case is the first presentation of FPIES to prunes (dehydrated plum). This case highlights that careful history taking can avoid unnecessary investigations and delay in diagnosing FPIES.

Persistent Hypoglycemia in Children: Targeted Gene Panel Improves the Diagnosis of Hypoglycemia Due to Inborn Errors of Metabolism

OBJECTIVES

To evaluate the role of next generation sequencing in genetic diagnosis of pediatric patients with persistent hypoglycemia.

STUDY DESIGN

Sixty-four patients investigated through an extensive workup were divided in 3 diagnostic classes based on the likelihood of a genetic diagnosis: (1) single candidate gene (9/64); (2) multiple candidate genes (43/64); and (3) no candidate gene (12/64). Subsequently, patients were tested through a custom gene panel of 65 targeted genes, which included 5 disease categories: (1) hyperinsulinemic hypoglycemia, (2) fatty acid-oxidation defects and ketogenesis defects, (3) ketolysis defects, (4) glycogen storage diseases and other disorders of carbohydrate metabolism, and (5) mitochondrial disorders. Molecular data were compared with clinical and biochemical data.

RESULTS

A proven diagnosis was obtained in 78% of patients with suspicion for a single candidate gene, in 49% with multiple candidate genes, and in 33% with no candidate gene. The diagnostic yield was 48% for hyperinsulinemic hypoglycemia, 66% per fatty acid-oxidation and ketogenesis defects, 59% for glycogen storage diseases and other carbohydrate disorders, and 67% for mitochondrial disorders.

CONCLUSIONS

This approach provided a diagnosis in ~50% of patients in whom clinical and laboratory evaluation did not allow identification of a single candidate gene and a diagnosis was established in 33% of patients belonging to the no candidate gene class. Next generation sequencing technique is cost-effective compared with Sanger sequencing of multiple genes and represents a powerful tool for the diagnosis of inborn errors of metabolism presenting with persistent hypoglycemia.

Inflammatory events during food protein-induced enterocolitis syndrome reactions

BACKGROUND

An increasing number of infants are diagnosed with food protein-induced enterocolitis syndrome (FPIES), a non-IgE-mediated food allergy. Until now, T-cell, food-specific mechanisms have been hypothesized.

METHODS

Sixteen children (11M, 5F), affected by FPIES from cow's milk, wheat, fruit, rice, and others, experienced 25 acute episodes managed at our emergency department (ED) and eight FPIES reactions during oral food challenges (OFC). We compared the laboratory data in resting conditions, in the absence of infectious diseases, with data collected during the 25 acute ED episodes (blood samples drawn at 2-12 hours) and the eight positive OFCs (three samples at 2, 6, and 12 hours). The onset of symptoms was used as a reference time point.

RESULTS

In basal conditions, total IgE, WBC, neutrophil and eosinophil count, CRP, and SGPT were found normal. LDH and SGOT values were high (627.81±97.88 and 45.75±10.26 UI/L, respectively). During ED reactions, LDH and SGOT increased to 794.21±247.28 (P=.028) and 51.08±16.99 UI/L (P=.14) and neutrophils count and CRP to 8.44±3.82×10³ /μL (P=.0009) and 3.27±5.73 mg/dL (P=.0014), respectively. During positive OFC, LDH and SGOT did not vary significantly; CRP increased from 0.14±0.18 to 2.49±3.65 mg/dL (P=.00189) and neutrophil count from 2.79±1.42 to 7.10±3.98×10³ /μL (P=.00096).

CONCLUSIONS

FPIES reactions are characterized by neutrophilia and by a time-dependent, significant increase in CRP, indicating that inflammatory mechanisms are in place. This suggests new directions for research on FPIES pathogenesis.

Non-IgE-mediated gastrointestinal food allergy

Non-IgE-mediated gastrointestinal food-induced allergic disorders (non-IgE-GI-FAs) account for an unknown proportion of food allergies and include food protein-induced enterocolitis syndrome (FPIES), food protein-induced allergic proctocolitis (FPIAP), and food protein-induced enteropathy (FPE). Non-IgE-GI-FAs are separate clinical entities but have many overlapping clinical and histologic features among themselves and with eosinophilic gastroenteropathies. Over the past decade, FPIES has emerged as the most actively studied non-IgE-GI-FA, potentially because of acute and distinct clinical features. FPIAP remains among the common causes of rectal bleeding in infants, while classic infantile FPE is rarely diagnosed. The overall most common allergens are cow's milk and soy; in patients with FPIES, rice and oat are also common. The most prominent clinical features of FPIES are repetitive emesis, pallor, and lethargy; chronic FPIES can lead to failure to thrive. FPIAP manifests with bloody stools in well-appearing young breast-fed or formula-fed infants. Features of FPE are nonbloody diarrhea, malabsorption, protein-losing enteropathy, hypoalbuminemia, and failure to thrive. Non-IgE-GI-FAs have a favorable prognosis; the majority resolve by 1 year in patients with FPIAP, 1 to 3 years in patients with FPE, and 1 to 5 years in patients with FPIES, with significant differences regarding specific foods. There is an urgent need to better define the natural history of FPIES and the pathophysiology of non-IgE-GI-FAs to develop biomarkers and novel therapies.

Differential diagnosis of food protein-induced enterocolitis syndrome

Purpose of review

To assess all the possible differential diagnosis of food protein-induced enterocolitis syndrome (FPIES), both in acute and chronic presentation, reviewing the data reported in published studies.

Recent findings

There is an increase of reported cases of FPIES in recent years. As the disease presents with nonspecific symptoms, it can be misunderstood in many ways. The differential diagnosis includes, in acute presentations, the following: sepsis, other infectious diseases, acute gastrointestinal episodes, surgical emergencies, food allergies. In its chronic forms, FPIES may mimic malabsorption syndromes, metabolic disorders, primary immunodeficiencies, neurological conditions, coagulation defects, and other types of non-IgE-mediated food allergy.

Summary

A thorough clinical evaluation, including symptoms, signs, and laboratory findings, is necessary to lead the clinicians toward the diagnosis of FPIES. The major reason for delayed diagnosis appears to be the lack of knowledge of the disease.