Heterogeneity of food protein-induced enterocolitis syndrome (FPIES)

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy with gastrointestinal symptoms such as vomiting and diarrhea. The development of international consensus guidelines for the diagnosis and management of FPIES in 2017 enabled us to compare patients worldwide, regardless of geographic variation in disease features. As a result, it has become clear that there is heterogeneity among patients with FPIES or that there are cases that partly fit the diagnostic criteria for FPIES but have different characteristics. This review highlights the heterogeneity in FPIES characteristics in terms of trigger foods, the age of onset, differences in geographic regions, and symptoms; it further proposes four disease entities, including acute FPIES in children, acute FPIES in adults, chronic FPIES, and early-onset neonatal FPIES, depending on the age of onset and presumed pathophysiology. The major symptoms at onset and trigger foods differ in acute FPIES in children, acute FPIES in adults, and chronic FPIES, whereas the disease entities may share a similar pathophysiology. Early-onset neonatal FPIES may have a different pathophysiology than acute or chronic FPIES, and may not necessarily fulfil the full diagnostic criteria for acute or chronic FPIES described in the international consensus guidelines. Due to the similarity in symptoms, early-onset neonatal FPIES may sometimes be misdiagnosed as necrotizing enterocolitis. We aim to increase awareness of FPIES among medical staff in pediatrics, neonatology, and internal medicine and promote research, to gain a better understanding of the heterogeneity and pathophysiology of FPIES.

Lymphocyte stimulation test for diagnosing hen's egg yolk-induced enterocolitis syndrome

Background

There is currently little research into factors predicting the results of an initial diagnostic oral food challenge (OFC) test for food protein-induced enterocolitis syndrome (FPIES).

Objective

The present study aimed to identify predictors of the diagnosis of hen's egg yolk-induced FPIES (HEY-FPIES).

Methods

The present monocentric study was performed at Tokyo Metropolitan Children's Medical Center and included patients who underwent hen's egg yolk OFC (HEY-OFC) between March 2018 and March 2023 to assess for HEY-FPIES. The baseline characteristics of the groups and HEY-OFC positivity or negativity were then compared. Univariate analysis was conducted by using the Mann-Whitney U test or Fisher exact test. Receiver operator characteristic analysis was used to create probability curves.

Results

In total, 35 patients were analyzed; of these, 17 were HEY-OFC-positive. No significant difference was observed between the HEY-OFC-positive and HEY-OFC-negative groups in terms of background factors except for the HEY-LST value, which was significantly higher in the HEY-LST group (P = .027). Receiver operator characteristic analysis demonstrated that the area under the curve for HEY-OFC positivity using the HEY-LST value was 0.719 (95% CI = 0.541-0.897). The statistically optimal cutoff value for the HEY-LST was 610%, which had a clinical sensitivity and specificity of 64.7% and 83.3%, respectively.

Conclusions

The present study demonstrated that the HEY-LST may be a useful predictor of the result of an initial OFC for HEY-FPIES.