The Role of IgE Sensitization in Acute FPIES: A Systematic Review and Meta-Analysis

Evidence on the role of immunoglobulin E (IgE) sensitization in acute food protein-induced enterocolitis syndrome (atypical FPIES) is limited. Initial reports claimed association with persistent disease; however, recent studies have not replicated this.

To systematically review the relationship between sensitization to the culprit food(s) in acute FPIES and the outcome of follow-up oral food challenges. To assess the rates of sensitization, seroconversion (ie, switch from negative tests to sensitization), and phenotype switch to IgE-mediated food allergy over time in individuals with acute FPIES.

Systematic review searching 10 databases. Studies of children and adults with an acute FPIES diagnosis assessing IgE sensitization to a culprit food at onset or follow-up measured by skin prick or serological test were included.

Of 1,830 studies identified, 53 were eligible including 3,514 participants. Ten studies had an analytical design assessing whether sensitization was associated with disease persistence, with 4 showing an association and 6 showing no association. In individuals with acute FPIES, the sensitization rate was 9.8% (95% confidence interval [95% CI 7.4%-12.1%; 34 studies, 2,587 participants, I² = 82%); the frequency of seroconversion was 1.1% (95% CI 0.1%-2.1%; 9 studies, 673 participants, I² = 32%); and phenotype switch occurred in 1.1% (95% CI 0.4%-1.7%; 14 studies, 935 participants, I² = 0%) and 13% (95% CI 5.5%-20.5%, 12 studies, 93 participants; I² = 18%) of sensitized participants.

We did not find consistent evidence for the relationship between IgE sensitization and FPIES persistence. We found phenotype switch to IgE-mediated food allergy is uncommon in acute FPIES. An IgE sensitization in FPIES does not have a clear relationship with clinical outcomes.