Effect of Maternal Egg Consumption on Breast Milk Ovalbumin Concentration

Abstract

Palmer D, Gold M, Makridess M. Clin Exp Allergy. 2008;38(7):1186–1191PURPOSE OF THE STUDY. To assess human milk ovalbumin concentrations after daily maternal ingestion of 1 cooked egg for a 3-week period.STUDY POPULATION. There were 32 mothers of singleton, breastfed, egg-sensitive infants with moderate-to-severe eczema. Egg sensitivity was identified by a positive skin-prick test result. Eczema was evaluated by using a standardized scoring system.METHODS. Families had an initial home visit by an experienced dietitian, which involved collection of demographic and dietary information. All women and children were asked to follow an egg-free diet from day 1 through the duration of the trial. Adherence to the egg-free diet was assessed via detailed dietary intake records for both mothers and children on days 1 to 3, 10 to 12, and 21 to 23. Mothers were randomly allocated to receive identical-appearing egg-free muffins or muffins containing 1 (55 g) whole egg. Each mother was given a 3-week supply of frozen muffins corresponding to her randomization group and consumed 1 muffin per day on days 3 through 23. Atopic dermatitis assessments were performed for each child at the commencement and completion of the trial. The mothers completed the Infant's Dermatitis Quality of Life Index 3 times during the trial. On days 3, 12, and 23, the mothers manually expressed 5 mL of breast milk into sterile containers before and 2, 4, and 6 hours after eating the test muffin. Breast milk samples were stored in the home freezer and collected on day 24. The breast milk samples were queried for ovalbumin concentration by using a sandwich enzyme-linked immunosorbent assay method. Breast milk ovalbumin concentrations (nanograms per milliliter) were plotted against time, and the resulting curve was used to determine peak ovalbumin concentrations and total ovalbumin excretions (nanograms per milliliter per hour). Independent-sample t tests, Mann-Whitney U tests, and Pearson's χ2 tests were used to investigate differences between the diet groups.RESULTS. Women in the egg group had higher ovalbumin concentrations in breast milk than did the control group at all time points. Within each dietary group, the frequency of ovalbumin detection, peak ovalbumin concentration, and total ovalbumin excretion did not differ at days 3, 12, and 23. Ovalbumin was not detected in the breast milk of 25% of the women in the egg group. Infant eczema symptom scores were significantly reduced with time for both groups.CONCLUSIONS. Human milk ovalbumin is related to maternal dietary egg intake. Comparable detection of ovalbumin across time suggests that ovalbumin does not accumulate in human milk. One quarter of the women had no ovalbumin detected in their breast milk on any of the study days, which suggests that some women either do not excrete ovalbumin in their breast milk when challenged with 1 egg or have delayed excretion beyond 6 hours. Maternal dietary avoidance of well-cooked egg may not be necessary for all breastfed infants with egg sensitivity and eczema.REVIEWERS COMMENTS. For breastfed infants with food allergy, strict avoidance of the offending food proteins for both mother and child is frequently recommended. Total dietary avoidance of egg is difficult for patients to achieve. Additional study is needed to substantiate or to refute the preliminary observation that regular maternal ingestion of a small quantity of well-cooked egg did not markedly exacerbate eczema symptoms in egg-sensitive breastfed infants.