Breast-Feeding of Allergic Infants

Abstract

Source: Isolauri E, Tahvanainen A, Peltola T, Arvola T. Breast-feeding of allergic infants. J Pediatr. 1999;134:27–32.To determine whether infants who develop atopic dermatitis (AD) while breast-feeding should continue to be breast-fed, Finnish investigators studied 100 infants with moderate or severe AD that began during exclusive breast-feeding and was followed after substitution of an amino acid-based formula. Outcome variables included the extent and severity of AD, extent of sensitization to dietary antigens (by radioallergosorbent assay and skin prick test), growth and nutritional status of the infant. The mean age at enrollment was 5 months (range 2–10 months) and AD began at a mean of 2 months (range 0.5–6 months). Infants were exclusively breast-fed for a mean of 4 months (range 0.5–7 months); only 17 had ingested cereal, 37 had a single exposure to cow’s milk-based formula at a mean age of 4 months (range 3–4.5 months), and two-thirds were receiving vegetable solids such as potato, rice, or cauliflower. With the onset of AD, all mothers altered their diet; 80% eliminated milk and milk products, eggs, and fish. The longer the period between the onset of AD and the cessation of breast-feeding, the more significant the risk was of poor growth (r = −.23, P = .03, adjusted for the effect of age). Following cessation of breast-feeding and institution of the amino acid-based formula, there were significant reductions in the extent and severity of AD, small but statistically significant increases in albumin and prealbumin, and improved linear growth. The authors conclude that infants with AD require allergen avoidance that, in some cases, may include cessation of breast-feeding.Although it is generally believed that breast-feeding reduces the frequency and severity of AD, some breast-fed infants develop the disease. As reported by Isolauri et al, above, and as discussed by Goldman in an accompanying editorial,1 one explanation for this observation, and the improvements that may accompany cessation of breast-feeding, is that infants become sensitized to antigenic maternal dietary proteins that are transferred in breast milk. Supporting this is the observation that maternal avoidance of cow’s milk, eggs, and fish reduces the incidence of allergic disorders in breast-fed infants.2 Improvements in AD accompanying a change from breast milk to an elemental formula may also be related to breast milk composition.2 Breast milk from mothers of infants with atopic disorders contains reduced amounts of long-chain unsaturated fatty acids that possess anti-allergic properties.2 Although the present study is well-designed, the duration of the intervention and timing of observations are not clearly defined. In addition, because some infants do not appear to have been exclusively breast-fed, sensitization may not have been due entirely to proteins in breast milk. In practice, premature cessation of nursing should not be advised lightly since breast-feeding has numerous benefits and elemental formulas are expensive. The diagnosis of AD must be secure with the exclusion of conditions that produce similar clinical findings (eg, seborrheic dermatitis, certain metabolic disorders, etc). If maternal dietary avoidance of potentially sensitizing proteins is to be initially undertaken, the mother’s nutritional needs should be assured.The authors postulate a delicate balance in the breast-fed allergic infant between immunoprotection and an inflammatory response. In discussing their results they note that (1) sustained food allergy may cause poor growth and (2) only extreme and demanding maternal elimination diets were considered by the mother to benefit the allergic infant. What should be the criteria for a trial of elemental or other types of formula in an atopic, exclusively breast-fed infant? The authors do not provide clear criteria, but imply that there is impaired growth associated with the onset of persistent atopic dermatitis that is unresponsive to treatment. For most infants, breast-feeding remains the best way to reduce the risk of allergy, as well as providing other benefits.