Minimally invasive biomarker studies in eosinophilic esophagitis: A systematic review.

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic, inflammatory disease of the esophagus that currently requires repeated endoscopic biopsies for diagnosis and monitoring because no reliable noninvasive markers have been identified. OBJECTIVE: To identify promising minimally invasive EoE biomarkers and remaining gaps in biomarker validation. METHODS: We performed a systematic review of EMBASE, Ovid MEDLINE, PubMed, and Web of Science from inception to June 6, 2017. Studies were included if patients met the 2007 consensus criteria for EoE diagnosis, a minimally invasive biomarker was assessed, and the study included at least 1 control for comparison. RESULTS: The search identified 2094 studies, with 234 reviewed at full-text level, and 49 included in the analysis (20 adult, 19 pediatric, 7 pediatric and adult, and 3 not stated). Most (26 of 49) were published after 2014. Thirty-five studies included healthy controls, 9 analyzed atopic controls, and 29 compared samples from patients with active and inactive EoE. Minimally invasive biomarkers were obtained from peripheral blood (n = 41 studies), sponge or string samples (n = 3), oral or throat swab secretions (n = 2), breath condensate (n = 2), stool (n = 2), and urine (n = 2). The most commonly reported biomarkers were peripheral blood eosinophils (n = 16), blood and string eosinophil granule proteins (n = 14), and eosinophil surface or intracellular markers (n = 12). EoE biomarkers distinguished active EoE from healthy controls in 23 studies, atopic controls in 2 studies, and inactive EoE controls in 20 studies. CONCLUSION: Several promising minimally invasive biomarkers for EoE have emerged; however, few are able to differentiate EoE from other atopic diseases.

Learning early about peanut-triggered food protein-induced enterocolitis syndrome.

Background: Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E mediated food allergy that typically presents with repetitive emesis and may be associated with lethargy, marked pallor, hypotension, hypothermia, and/or diarrhea. Although many foods are known to cause FPIES, peanut-triggered FPIES is emerging due to changes in the feeding practice guidelines, which recommends early peanut introduction in infants. Objective: We aimed to characterize peanut-triggered acute FPIES cases in our pediatric population and to describe their attributes, treatment, and outcomes. We hypothesized that increases in the incidence of peanut-triggered FPIES coincided with implementation of the guidelines for early peanut introduction. Methods: A retrospective chart review was conducted of pediatric patients who presented to Phoenix Children's Hospital Emergency Department and subspecialty clinics during a 6-year period (January 2013 to September 2019). Results: Thirty-three cases of patients with acute FPIES were identified, five of which were peanut triggered. In those patients with peanut-triggered FPIES, the median age for peanut introduction was 7 months (range, 5-24 months). Two patients had positive peanut skin-prick test results. All five cases were identified in the past 2 years (2018 to 2019). No peanut-triggered reactions were documented in the preceding 4-year period (2013 to 2017). Conclusion: Peanut may be an emerging trigger of acute FPIES, coinciding with an earlier introduction of peanut in the infant diet after implementation of the new addendum guidelines for the prevention of peanut allergy. Oats and rice were the most common triggers of acute FPIES in our cohort. Further study will help clarify the significance and reproducibility of these findings.