To Diet or Not to Diet This Is the Question in Food-Protein-Induced Allergic Proctocolitis (FPIAP)-A Comprehensive Review of Current Recommendations.

Food-protein-induced allergic proctocolitis (FPIAP) is an increasingly reported transient and benign form of colitis that occurs commonly in the first weeks of life in healthy breastfed or formula-fed infants. Distal colon mucosal inflammation is caused by a non-IgE immune reaction to food allergens, more commonly to cow's milk protein. Rectal bleeding possibly associated with mucus and loose stools is the clinical hallmark of FPIAP. To date, no specific biomarker is available, and investigations are reserved for severe cases. Disappearance of blood in the stool may occur within days or weeks from starting the maternal or infant elimination diet, and tolerance to the food allergen is typically acquired before one year of life in most patients. In some infants, no relapse of bleeding occurs when the presumed offending food is reassumed after a few weeks of the elimination diet. Many guidelines and expert consensus on cow's milk allergy have recently been published. However, the role of diet is still debated, and recommendations on the appropriateness and duration of allergen elimination in FPIAP are heterogeneous. This review summarizes and compares the different proposed nutritional management of infants suffering from FPIAP, highlighting the pros and cons according to the most recent literature data.

[Association of pregnancy factors with cow's milk protein allergy in infants].

OBJECTIVE: To preliminarily explore the association of pregnancy factors with cow's milk protein allergy in infants. METHODS: This study was based on data from a subcohort of a study called genetic susceptibility to cow's milk allergy in Chinese children, including infants born in Peking University People's Hospital between March 1, 2020, and December 31, 2020. The infants were divided into a cow's milk protein allergy (CMPA) group and a control group according to whether they had developed cow's milk protein allergy at the age of 1 year. We retrospectively collected the clinical data of infants and their mothers before and during pregnancy, and analyzed the association of multiple factors during pregnancy with cow's milk protein allergy in infants. RESULTS: A total of 278 infants were enrolled in this study, including 52 infants with CMPA and 226 infants without CMPA. Among them, there were 143 boys and 135 girls. The proportion of male infants in the CMPA group (69.2%) was higher than that in the control group (47.3%), and the difference was statistically significant (P=0.004). There were no significant differences in the distribution of birth weight, gestational age at birth, low-birth-weight infants, premature, umbilical cord entangle neck, and neonatal asphyxia between the CMPA group and the control group (P>0.05). The proportion of mothers complicated with autoimmune diseases, anemia or antibiotics exposure during pregnancy in the CMPA group was higher than that in the control group, and there were statistical differences between the two groups (P < 0.05). There was no significant difference in the distribution of other pregnancy complications between the two groups (P>0.05), such as eclampsia/preeclampsia, chronic hypertension/gestational hypertension, diabetes/gestational diabetes, thyroid diseases, and so on. There was no significant difference in the overall distribution of some blood routine indexes during pregnancy between the CMPA group and the control group (P>0.05). Multivariate Logistic regression analysis showed that male infant, mothers complicated with autoimmune diseases or anemia, antibiotic exposure during pregnancy were independent risk factors for cow's milk protein allergy. CONCLUSION: Male infant, mothers complicated with autoimmune diseases or anemia, antibiotic exposure during pregnancy were independent risk factors for cow's milk protein allergy.

A Lipopolysaccharide-Enriched Cow's Milk Allergy Microbiome Promotes a TLR4-Dependent Proinflammatory Intestinal Immune Response.

We have previously reported that the gut microbiota of healthy infants harbors allergy-protective bacteria taxa that are depleted in infants with cow's milk allergy (CMA). Few reports have investigated the role of the gut microbiota in promoting allergic responses. In this study we selected a CMA-associated microbiota with increased abundance of Gram-negative bacteria for analysis of its proinflammatory potential. LPS is the major component of the outer membrane of Gram-negative bacteria. Colonization of mice with a global or conditional mutation of the LPS receptor TLR4 with this CMA microbiota induced expression of serum amyloid A1 (Saa1) and other Th17-, B cell-, and Th2-associated genes in the ileal epithelium in a TLR4-dependent manner. In agreement with the gene expression data, mice colonized with the CMA microbiota have expanded populations of Th17 and regulatory T cells and elevated concentrations of fecal IgA. Importantly, we used both antibiotic-treated specific pathogen-free and germ-free rederived mice with a conditional mutation of TLR4 in the CD11c+ compartment to demonstrate that the induction of proinflammatory genes, fecal IgA, and Th17 cells is dependent on TLR4 signaling. Furthermore, metagenomic sequencing revealed that the CMA microbiota has an increased abundance of LPS biosynthesis genes. Taken together, our results show that a microbiota displaying a higher abundance of LPS genes is associated with TLR4-dependent proinflammatory gene expression and a mixed type 2/type 3 response in mice, which may be characteristic of a subset of infants with CMA.

Outcomes and factors associated with tolerance in infants with non-IgE-mediated cow's milk allergy with gastrointestinal manifestations.

OBJECTIVES: To evaluate outcomes of oral food challenge (OFC) test to assess tolerance in infants with non-IgE-mediated cow's milk allergy (CMA) with gastrointestinal manifestations and explore clinical data predictive of these outcomes. METHODS: Single-center retrospective study including infants (age < 12 months) who were referred for CMA between 2000 and 2018 and underwent OFC on follow-up. A univariate logistic regression test was performed to evaluate variables associated with the outcomes of the follow-up OFC test. RESULTS: Eighty-two patients were included, 50% were male. Eighteen patients had a positive OFC test (22%). Most patients had presented with hematochezia (77%). The median age of symptom onset was 30 days. Two-thirds of the patients were on appropriate infant formula (extensively hydrolyzed or amino acid-based formula), exclusively or in association with breastfeeding. The median time on an elimination diet before the OFC test was 8 months (Q1 6 - Q3 11 months). All cases with positive follow-up OFC tests (n = 18) had been exposed to cow's milk-based formula before the first clinical manifestation of CMA. Five out of eight cases with Food Protein-Induced Enterocolitis Syndrome (FPIES) had positive OFC tests. Exposure to cow's milk-based formula before diagnosis, a history of other food allergies, hematochezia and diarrhea were predictors of a positive OFC test. CONCLUSIONS: In infants with non-IgE-mediated CMPA with gastrointestinal manifestations, the use of cow's milk-based formula, a history of other food allergies, and hematochezia and diarrhea upon initial presentation were associated factors for the later achievement of tolerance.

Cow's Milk-Related Symptom Score (CoMiSS): From Bristol to Brussels Stool Scale.

OBJECTIVES: The Cow's Milk-related Symptom Score (CoMISS) is an awareness tool for evaluating cow's milk-related symptoms in otherwise healthy infants <1 year of age. This study assessed whether replacing the Bristol Stool Form Scale (BSFS) with the Brussels Infants and Toddlers Stool Scale (BITSS) in non-toilet-trained infants would modify the overall CoMiSS and change the clinical approach regarding potential cow's milk allergy. METHODS: Non-toilet-trained infants aged <13 months were assessed by CoMiSS using the 7 images from the BSFS (CoMiSS-BSFS) compared to the 4 images of stools from BITSS (CoMiSS-BITSS). The Wilcoxon signed-rank test and Pearson correlation coefficient were calculated. A post hoc analysis using identical tests was performed in subsets of CoMiSS-BSFS scores ≥10, ≥12, ≤5, and ≥6. RESULTS: Eight hundred forty-four pairwise scores were collected. Applying the Wilcoxon test over the complete dataset, the difference between CoMiSS-BSFS and CoMiSS-BITSS was statistically significant ( P < 0.001). However, there was no significant difference in the subsets with CoMiSS-BSFS ≥10, ≥12, and ≥6 ( P = 0.84, P = 0.48, and P = 0.81, respectively). The significant difference remained restricted to the group with CoMiSS-BSFS ≤5, considered at low risk for CM-related symptoms ( P < 0.001). CONCLUSION: Replacing BSFS with BITSS does not change the cutoff for awareness of possible CM-related symptoms and will not impact the use of CoMiSS in clinical practice. Changes in CoMiSS remained limited to the subgroup with a low risk for CM-related symptoms.

Very early onset perinatal constipation: Can it be cow's milk protein allergy?

Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung's disease (HD), meconium ileus due to Cystic Fibrosis, etc. The diagnosis of HD particularly warrants invasive testing to confirm the diagnosis, such as anorectal manometry or rectal suction biopsy. What if there was another etiology of perinatal constipation, that is far lesser known? Cow's milk protein allergy (CMPA) is often diagnosed in infants within the first few weeks of life, however, there are studies that show that the CMPA allergen can be passed from mother to an infant in-utero, therefore allowing symptoms to show as early as day one of life. The presentation is more atypical, with perinatal constipation rather than with bloody stools, diarrhea, and vomiting. The diagnosis and management would be avoidance of cow's milk protein within the diet, with results and symptom improvement in patients immediately. Therefore, we discuss whether an alternative pathway to address perinatal constipation should be further discussed and implemented to potentially avoid invasive techniques in patients. This entails first ruling out CMPA with safe, noninvasive techniques with diet modification, and if unsuccessful, then moving forward with further diagnostic modalities.

Oral food challenge in children with contact urticaria in reaction to cow’s milk

Objective: To evaluate the relationship between the occurrence of contact urticaria in reaction to cow’s milk in infants and the diagnosis of cow’s milk allergy (CMA) established by supervised oral food challenge. Methods: In this cross-sectional study, we identified 184 children who had undergone 221 oral food challenge (OFC) at a CMA reference center between July 2015 and August 2019. Of these, 23 (12.5%) had a history of contact urticaria to cow’s milk and underwent a total of 30 OFC. Baked cow’s milk OFC were excluded, and 21 children were included in the study. All data from clinical history and allergy tests (serum-specific IgE dosages and skin prick test [SPT] with reconstituted cow’s milk formula) were recorded on standardized forms. The challenge was conducted with reconstituted cow’s milk formula in increasing volumes every 15–20 min. Results: 24 OFC were performed; 13/24 (54.2%) for diagnostic purpose and 11/24 (45.8%) to evaluate cow’s milk tolerance. Allergy tests were positive in 14 patients (87.5%). Positive oral challenge outcomes were identified in 7/24. One patient had a late flare of atopic dermatitis and five children presented with immediate urticaria (two generalized urticaria and three perioral urticaria). The median papule diameter was 6.5 mm in patients with a positive OFC and 3.75 mm in the negative group (P = 0.02). Conclusion: The occurrence of contact urticaria might be the only manifestation among infants sensitized to cow’s milk with tolerance to oral ingestion. Reactions due to oral challenge were related to a larger wheal diameter on the SPT (AU)

Identification of cow milk epitopes to characterize and quantify disease-specific T cells in allergic children.

BACKGROUND: Cow milk (CM) allergy is the most prevalent food allergy in young children in the United States and Great Britain. Current diagnostic tests are either unreliable (IgE test and skin prick test) or resource-intensive with risks (food challenges). OBJECTIVE: We sought to determine whether allergen-specific T cells in CM-allergic (CMA) patients have a distinct quality and/or quantity that could potentially be used as a diagnostic marker. METHODS: Using PBMCs from 147 food-allergic pediatric subjects, we mapped T-cell responses to a set of reactive epitopes in CM that we compiled in a peptide pool. This pool induced cytokine responses in in vitro cultured cells distinguishing subjects with CMA from subjects without CMA. We further used the pool to isolate and characterize antigen-specific CD4 memory T cells using flow cytometry and single-cell RNA/TCR sequencing assays. RESULTS: We detected significant changes in the transcriptional program and clonality of CM antigen-specific (CM+) T cells elicited by the pool in subjects with CMA versus subjects without CMA ex vivo. CM+ T cells from subjects with CMA had increased percentages of FOXP3+ cells over FOXP3- cells. FOXP3+ cells are often equated with regulatory T cells that have suppressive activity, but CM+ FOXP3+ cells from subjects with CMA showed significant expression of interferon-responsive genes and dysregulated chemokine receptor expression compared with subjects without CMA, suggesting that these are not conventional regulatory T cells. The CM+ FOXP3+ cells were also more clonally expanded than the FOXP3- population. We were further able to use surface markers (CD25, CD127, and CCR7) in combination with our peptide pool stimulation to quantify these CM+ FOXP3+ cells by a simple flow-cytometry assay. We show increased percentages of CM+ CD127-CD25+ cells from subjects with CMA in an independent cohort, which could be used for diagnostic purposes. Looking specifically for TH2 cells normally associated with allergic diseases, we found a small population of clonally expanded CM+ cells that were significantly increased in subjects with CMA and that had high expression of TH2 cytokines and pathogenic TH2/T follicular helper markers. CONCLUSIONS: Overall, these findings suggest that there are several differences in the phenotypes of CM+ T cells with CM allergy and that the increase in CM+ FOXP3+ cells is a potential diagnostic marker of an allergic state. Such markers have promising applications in monitoring natural disease outgrowth and/or the efficacy of immunotherapy that will need to be validated in future studies.

The Impact of Infant Feeding Regimen on Cow's Milk Protein Allergy, Atopic Dermatitis and Growth in High-Risk Infants during the First 6 Months of Life: The Allergy Reduction Trial.

The development of early-onset cow's milk protein allergy and atopic dermatitis during the first months of life is multifactorial, including both genetic and nutritional aspects. This study aims to assess the impact of different feeding patterns on the incidence of cow's milk protein allergy, atopic dermatitis, and growth among infants with a family history of allergy. A total of 551 high-risk infants were randomly recruited from 3 European countries in three feeding regimens: exclusive breastfeeding, partially hydrolyzed formula, or standard formula with intact protein either exclusively or supplementary to breastfeeding. During the first 6 months of intervention, amongst infants with a family history of atopic dermatitis, 6.5% of partially hydrolyzed formula-fed infants and 22.7% of exclusively breastfed infants (p = 0.007) presented with atopic dermatitis respectively. Growth as assessed by weight increase did not differ between the aforementioned groups. Although cow's milk protein allergy was not related to the different milk feeding regimens in the whole cohort, when adjusting for high breast milk intake, the respective incident was significantly lower in the infants consuming partially hydrolyzed formula (p < 0.001). This data indicates that a specific partially hydrolyzed formula could serve as a more appropriate complement to breast milk compared to a standard intact protein formula in high-risk infants, to reduce the incidence of atopic dermatitis.

Associations between functional constipation and non-IgE-mediated food allergy in infants and children.

BACKGROUND: The non-IgE-mediated food allergy (non-IgE-FA) is less prevalent than IgE-mediated food allergy, and their relationship with functional constipation (FC) needs to be clarified. METHODS: A total of 305 infants and children with constipation treated in the Department of Pediatric Gastroenterology, Children's Hospital of Nanjing Medical University, from July 2020 to December 2021 were included in this study. Four cases with organic lesions were excluded. Among 301 diagnosed with FC, according to ROME IV criteria, 81 cases with allergy-related indicators were further evaluated for food allergy by food-specific IgG antibody test, allergen- specific IgE antibody detection, skin prick test, and food avoidance and reintroduction. RESULTS: A total of 45 cases with FC were diagnosed with food allergy, and the incidence rate was 15%. Among the 45 patients, 35 cases (77.8%) had FC with non-IgE-FA. The main clinical symptoms or signs included anal fissure, abdominal pain, and pain during defecation. The most prevalent allergic foods were cow's milk, eggs, fish, and shrimp. Ten (22.2%) cases reported FC with mixed food allergy, including both non-IgE-mediated and IgE-mediated food allergy. This study focused on non-IgE-mediated food allergy-related FC. CONCLUSION: Our results showed that the incidence of food allergy in infants and children with FC was 15%, which was mainly mediated by non-IgE-FA. The main clinical symptoms or signs in these cases included anal fissure, abdominal pain, and pain during defecation, and the main allergens included milk, eggs, fish, and shrimp.

The role of the atopy patch test in the diagnostic work-up of non-IgE gastrointestinal food allergy in children: a systematic review.

The "Atopy Patch Test" (APT) has been proposed as a diagnostic tool for food allergies (FA), especially in children with FA-related gastrointestinal symptoms. However, its diagnostic accuracy is debated, and its usefulness is controversial. The aim of this systematic review was to evaluate the APT diagnostic accuracy compared with the diagnostic gold standard, i.e., the oral food challenge (OFC), in children affected by non-IgE mediated gastrointestinal food allergies, including the evaluation in milk allergic subgroup. Both classical non-IgE mediated clinical pictures and food induced motility disorders (FPIMD) were considered. The search was conducted in PubMed and Scopus from January 2000 to June 2022 by two independent researchers. The patient, intervention, comparators, outcome, and study design approach (PICOS) format was used for developing key questions, to address the APT diagnostic accuracy compared with the oral food challenge (OFC). The quality of the studies was assessed by the QUADAS-2 system. The meta-analysis was performed to calculate the pooled sensitivity, specificity, DOR (diagnostic odds ratio), PLR (positive likelihood ratio), and NLR (negative likelihood ratio) with their 95% confidence intervals (CI). Out of the 457 citations initially identified via the search (196 on PubMed and 261 on Scopus), 37 advanced to full-text screening, and 16 studies were identified to be included in the systematic review. Reference lists from relevant retrievals were searched, and one additional article was added. Finally, 17 studies were included in the systematic review. The analysis showed that APT has a high specificity of 94% (95%CI: 0.88-0.97) in the group of patients affected by FPIMD. Data showed a high pooled specificity of 96% (95% CI: 0.89-0.98) and the highest accuracy of APT in patients affected by cow's milk allergy (AUC = 0.93).      Conclusion: APT is effective in identifying causative food in children with food-induced motility disorders.  What is Known: • Atopy patch test could be a useful diagnostic test for diagnosing food allergy, especially in children with food allergy-related gastrointestinal symptoms. What is New: • Atopy patch test may be a useful tool in diagnosing non IgE food allergy, especially in children with food-induced gastrointestinal motility disorders and cow's milk allergy.

CD4+CD25+CD127loFOXP3+ cell in food allergy: Does it predict anaphylaxis?

Background: Food allergy (FA), hence the incidence of food anaphylaxis, is a public health problem that has increased in recent years. There are still no biomarkers for patients with FA to predict severe allergic reactions such as anaphylaxis. Objective: There is limited information on whether regulatory T (Treg) cell levels are a biomarker that predicts clinical severity in cases presenting with FA, and which patients are at a greater risk for anaphylaxis. Methods: A total of 70 children were included in the study: 25 who had IgE-mediated cow’s milk protein allergy (CMPA) and presented with non-anaphylactic symptoms (FA/A−), 16 who had IgE-mediated CMPA and presented with anaphylaxis (FA/A+) (a total of 41 FA cases), and a control group consisting of 29 children without FA. The study was conducted by performing CD4+CD25+CD127loFOXP3+ cell flow cytometric analysis during resting at least 2 weeks after the elimination diet to FA subjects. Results: When the FA group was compared with healthy control subjects, CD4+CD25+CD127loFOXP3+ cell rates were found to be significantly lower in the FA group (p < 0.001). When the FA/A− and FA/A+ groups and the control group were compared in terms of CD4+CD25+CD127loFOXP3+ cell ratios, they were significantly lower in the FA/A− and FA/A+ groups compared to the control group (p < 0.001). Conclusions: Although there was no significant difference between the FA/A+ group and the FA/A− group in terms of CD4+CD25+CD127loFOXP3+ cells, our study is important, as it is the first pediatric study we know to investigate whether CD4+CD25+CD127loFOXP3+ cells in FA predict anaphylaxis (AU)

Facial atopic dermatitis is associated with sensitization to cow's milk, egg whites, and peanuts in children under 36 months.

Atopic dermatitis (AD) in early childhood often precedes the development of food sensitization and allergy, but the role of treating AD to prevent food allergy remains poorly understood. Our objective was to assess the relationship between facial dermatitis and food sensitization to cow's milk, egg whites, and peanuts in early childhood, as aggressive treatment of facial dermatitis could serve as a potential opportunity for food sensitization prevention. By 3 years of age, food sensitization levels to cow's milk, egg whites, and peanuts were 48% greater in children with facial AD than in children with no facial involvement of their AD. Additional research is needed to determine if facial involvement of AD in infants and young children is associated with increased food allergy.

Case report: Pneumatosis in a neonate with thrombocytopenia absent radius syndrome.

BACKGROUND: Thrombocytopenia absent radius (TAR) syndrome is a rare disease with an estimated prevalence of one in 200,000 live births. TAR is associated with cardiac and renal anomalies as well as gastrointestinal problems such as cow's milk protein allergy (CMPA). Typically neonates with CMPA present with mild intolerance, with few reports in the literature of more severe intolerance resulting in pneumatosis. We present a case of a male infant with TAR syndrome who developed gastric and colonic pneumatosis intestinalis. CASE DESCRIPTION: An eight-day-old male infant born at 36 weeks gestation with a diagnosis of TAR, presented with bright red blood in his stool. At this time he was on full formula feeds. Given continued bright red blood within his stool, an abdominal radiograph was obtained which was consistent with colonic and gastric pneumatosis. A complete blood count (CBC) was notable for worsening thrombocytopenia, anemia and eosinophilia. Once enteral feeds were held there was rapid resolution of the radiographic findings and resolution of his bloody stool. He was ultimately diagnosed with a CMPA. CONCLUSION: Though there are reports of CMPA in patients with TAR, the severity of this patient's presentation with both colonic and gastric pneumatosis is unique. Without the knowledge of the association of CMPA with TAR, this case could have been misdiagnosed and led to reintroduction of cow's milk containing formula, resulting in further complications. This case highlights the importance of a timely diagnosis and severity of CMPA in this population.

Dietary Factors May Delay Tolerance Acquisition in Food Protein-Induced Allergic Proctocolitis.

BACKGROUND: Dietary and environmental factors may influence tolerance acquisition in food protein-induced allergic proctocolitis (FPIAP). This retrospective observational study explored the role of maternal diet during pregnancy and breastfeeding in tolerance acquisition in infantile FPIAP. METHODS: Breastfed infants with FPIAP from six diverse regions in Greece were divided into two groups, based on development of tolerance to the trigger food: Group A (n = 43), before, and Group B (n = 53), after, the 6th month of age. Maternal diet during pregnancy and breastfeeding was elicited using the Mediterranean Diet Score Questionnaire and the Mediterranean Oriented Culture Specific Semi-Quantitative Food Frequency Questionnaire. RESULTS: Mean age at diagnosis of FPIAP (1.5 months) and weaning (5.5 months) were the same in both groups. The main trigger was cow's milk. Group A received infant milk formula earlier than Group B. Group B had a higher incidence of asthma/wheeze, siblings with milk allergy, maternal smoking and rural residence. On multivariate analysis, earlier resolution of FPIAP was associated with higher maternal education and with salt intake and consumption of goat/sheep cheese during pregnancy and olive oil during breastfeeding. Consumption of multivitamins during pregnancy and meat, winter fruits, green vegetables, butter, salt, "ready-to-eat" meals and pastries during breastfeeding were correlated with longer duration of symptoms. CONCLUSIONS: Mothers of children with FPIAP to cow's milk protein can be advised to eat more yogurt, cheese and olive oil during subsequent pregnancies, and avoid multivitamins, grilled food, "ready-to-eat" meals, pastries, meat and alcohol during breastfeeding, to reduce the duration of FPIAP presenting in future infants.

Cow's milk allergy in children impacts parental or caregiver calcium intake.

Food allergies have become a global epidemic, affecting more than 10% of the population and 8% of children worldwide. Eliminating or limiting a food group from the diet can adversely impact micronutrient consumption. Milk allergies can impact the amount of calcium consumed in the diet, serving as a barrier to meeting daily calcium needs. Previous research evaluates the nutritional impact food allergies may have on children diagnosed with food allergies; however, there is a marked gap in literature that investigates the impact that children's allergy may have on their parent or caregiver. We hypothesized that milk elimination in a child's diet resulting from a milk allergy is associated with inadequate calcium intake among parents. Study participants (n = 55) lived in the United States and included parents or caregivers of a child with a diagnosed milk allergy (experimental group) and parents of a child without a milk allergy (control group). Calcium intake was estimated by using the validated Calcium Assessment Tool. Results demonstrated that the experimental group consumed significantly less calcium (273 mg/d) than the control group (520 mg/d; P < .01). Notably, both groups consumed inadequate calcium relative to the calcium Recommended Dietary Allowance for adults of 1000 mg/d, although calcium supplementation was not assessed in this study. Key findings from this study indicate widespread inadequate dietary calcium intake and suggest a need for increased calcium consumption in this population.

Assessment of intracellular zinc levels in infants with food protein-induced allergic proctocolitis.

BACKGROUND: Food protein-induced allergic proctocolitis (FPIAP) is characterized by bloody stools in well-appearing infants. Zinc is a micronutrient that plays a crucial role in immune modulation and is essential for cellular function during immune response. Although there are studies on the assessment of intracellular zinc levels in allergic diseases, no data is available on erythrocyte zinc levels of patients with FPIAP. OBJECTIVE: This study aimed to assess the erythrocyte zinc levels of children with allergic proctocolitis and compare zinc levels with clinical and demographic characteristics. METHODS: This was a case-control study that prospectively compared 50 patients with FPIAP and 50 healthy children without malnutrition. The erythrocyte zinc levels of children were determined using atomic absorption spectrophotometry. RESULTS: Fifty patients with FPIAP, including 28 (51%) girls, with median age of 7.1 ± 2.9 (3-14) months and 50 healthy children, including 26 (53.1%) girls, with median age of 7.7 ± 2.8 (3-13) months were included in the study. Seventy percent (n = 35) of the patients with FPIAP started to have symptoms while they were exclusively breastfeeding. Offending allergen foods were cow's milk (78%), egg (40%), sesame (10%), hazelnut (8%), almond (6%), beef (6%), and peanuts (6%, n = 3). Intracellular (erythrocyte) zinc levels in patients with FPIAP were lower than in the healthy control group (495.5 ± 134 µg/dL, 567.3 ± 154.4 µg/dL, respectively, P = 0.01). Patients with FPIAP aged younger than 6 months had lower intracellular zinc levels compared with those aged above 6 months (457 ± 137 µg/dL; 548 ± 112 µg/dL, respectively, P = 0.01). There was no relationship between zinc levels and time of symptom onset, presence of concomitant disease, being allergic to multiple foods, and family history of atopy (P > 0.05). CONCLUSIONS: FPIAP is a food allergy with limited information on its pathogenesis. Considering the beneficial effects on gastrointestinal system epithelia, zinc may be involved in the pathogenesis of FPIAP. Future comprehensive prospective research on this subject is of importance.

The long-term clinical course of protein-losing enteropathy combined with iron deficiency anemia in Korean toddlers: Possible association with cow's milk protein.

BACKGROUND: Protein-losing enteropathy (PLE), a rare condition with excessive gastrointestinal protein loss, presents with hypoalbuminemia, edema, or ascites. Several cases of PLE combined with severe iron deficiency anemia (IDA) have been reported in infants and toddlers that were considered to result from excessive cow's milk consumption, although the mechanism has not been clearly established. METHODS: We retrospectively reviewed the clinical, laboratory, endoscopic, and radiologic characteristics of patients diagnosed and treated for PLE with IDA between 2015 and 2021. Long-term outcomes were analyzed according to dietary intervention during the follow-up period. RESULTS: A total of 10 patients aged 7.0-26.7 months were enrolled in the study and the median follow-up duration of them was 9.4 months (range, 1.3-18.0). Six of them were fed powdered formula, while two were fed whole cow's milk, and their median daily intake was 700 mL (range, 300-900). The times to normalization of hemoglobin, albumin, and eosinophil count were shorter in patients with dietary elimination of cow's milk protein immediately after diagnosis compared to those with reduced intake or no dietary change. CONCLUSION: Early complete elimination of cow's milk protein should be considered, especially if the laboratory parameters are not normalized with adequate iron supplementation even though the clinical symptoms show improvement. We would like to draw attention to the possibility of the cow's milk protein in the pathogenesis of the condition through the non-IgE-mediated immune reactions.

Effects of regular soy formula intake between 1 and 2 months of age on food sensitization in infancy.

BACKGROUND: The effects of regular soy formula (SF) intake on the development of food sensitization in infancy remain unclear. This study aimed to assess the effects of regular SF intake between 1 and 2 months of age on food sensitization development by 6 months of age. METHODS: Using data from a randomized controlled trial of a birth cohort from four Japanese hospitals that assessed cow's milk allergy development, we performed a retrospective cohort study of 235 infants who avoided cow's milk formula and supplemented breastfeeding with SF as required between 1 and 2 months of age. Regular SF intake was defined as SF consumption of ≥14 days per month and ≥1350 ml per month. Food sensitization was defined as positive skin prick test reactions to hen's egg, cow's milk, wheat, and/or soy. Using multivariable logistic regression models that adjusted for parental, perinatal, and environmental factors, we calculated the adjusted odds ratios of regular SF intake for food, hen's egg, and cow's milk sensitization by 6 months of age. RESULTS: From the 235 participants, 114 (48.5%) had regular SF intake. The adjusted odds ratios of regular SF intake for food, hen's egg, and cow's milk sensitization were 0.32 (95% confidence interval: 0.16-0.62, p = .0007), 0.42 (0.20-0.88, p = .02), and 0.33 (0.14-0.81, p = .02), respectively. CONCLUSION: Regular SF intake between 1 and 2 months of age in infants avoiding cow's milk formula was significantly associated with a reduced risk of food sensitization in infancy.