Absorption of food protein antigen in infants with food protein-induced enterocolitis

Abstract

Increased gastrointestinal absorption of intact antigen with systemic immunization has been considered a major etiologic factor in the development of food sensitivity. We attempted to test this hypothesis in infants with suspected food protein-induced entercolitis by measuring serum ovalbumin (OVA) concentrations after ingestion of egg white (prior to the performance of good challenges to establish this diagnosis). We first noted significant underestimation of serum OVA concentrations in the presence of even low serum anti-OVA antibody concentrations (greater than 1:12). Next, using selected noninhibitory sera, we found that all infants studied absorbed some OVA, there was no correlation between serum OVA levels and age (3-11 months), and there was no significant difference between serum OVA concentrations in infants who subsequently had positive oral food challenge responses (120 +/- 67 ng/ml) and a matched group with negative challenges (102 +/- 80). These data do not support the hypothesis that "intestinal closure" (antigen exclusion) occurs in the neonatal period or the role of antigen absorption as the major etiological factor in the development of food sensitivity. Better methods of quantitating macromolecular absorption must be developed before the role of antigen absorption in food sensitivity can be assessed. Of note, urinary excretion of intact OVA also occurred. This varied greatly from one voiding to the next and continuing for at least 13 hr after ingestion.

Definition, etiology, and diagnosis of food protein-induced enterocolitis syndrome

“…This local inflammation may be mediated by activated peripheral mononuclear cells, increased TNF-α, and decreased expression of TGF-β receptors in the intestinal mucosa [23]. However, baseline antigen absorption is normal and does not predispose to FPIES [41]. Methomoglobinemia described in case of severe acute FPIES have been attributed to the local intestinal inflammation [24].…”

Food protein-induced enterocolitis syndrome

“…Previous endoscopic evaluations and biopsies in infants with FPIES highlight inflammatory responses in the colon, with diffuse colitis and variable ileal involvement. Colon mucosa can be mildly friable or show severe spontaneous hemorrhage, and minute ulcers can be found [3, 11,36]. Crypt abscesses are identified in some patients [37].…”

Food Protein–Induced Enterocolitis Syndrome

“…Data from a challenge-based study in Korea show that CM-FPIES and soy FPIES may resolve significantly more rapidly than previously assumed [25]. In pooling data from multiple small cohorts, patients seem to be able to tolerate CM at around 3 years of age, although results from 2 recent large cohorts showed that tolerance developed later [13,15,21,24,25,37,38,[45][46][47][48][49][50][51][52][53][54][55][56][57][58]. In a large US case series, the median age of resolution for CM-FPIES was 5.1 years, and in the UK, 25% of the patients had persistent CM-FPIES at 8 years of age [59].…”

“…This inflammation is hypothesized to result in increased intestinal permeability leading to a fluid shift into the gastrointestinal lumen. In acute FPIES, the effect of ondansetron on resolution of emesis suggests a potential neuroimmune mechanism and serotonin pathway involvement [57]. Current evidence regarding potential immunologic pathogenic mechanisms is summarized in Table 9.…”