Km. Saarinen et E. Savilahti, Infant feeding patterns affect the subsequent immunological features in cow's milk allergy, CLIN EXP AL, 30(3), 2000, pp. 400-406
Background The first exposure to food antigens provokes an immune reaction
in an infant, its type depending on the quantity and frequency of doses and
the age at introduction, and also being influenced by genetic factors. Mos
t infants develop tolerance to food antigens, but in a small minority they
provoke adverse symptoms.
Objective To study the effects of breast and formula feeding and other envi
ronmental and genetic factors on the subsequent type of cow's milk allergy
classified by the presence or absence of immunoglobulin (Ig) E antibodies t
o cow's milk.
Methods A cohort of 6209 infants was followed prospectively From birth for
symptoms of cow's milk allergy. The infant-feeding regimen was recorded at
the maternity hospital and at home. At a mean age of 6.7 months, a total of
118 infants (1.9%) reacted adversely to a challenge with cow's milk. Befor
e the challenge, the response to a skin-prick test with cow's milli and ser
um IgE cow's milk antibodies was measured.
Results At challenge, 75 (64%) infants showed IgE-positive reactions to cow
's milk, their most common symptom being acute-onset urticaria. Significant
risk factors for the presence of IgE cow's milk antibodies in allergic inf
ants were long breast-feeding (odds ratio [OR] 3.9, 95% confidence interval
[CI] 1.6-9.8), exposure to cow's milk at the maternity hospital (OR 3.5, 9
5% CI 1.2-10.1) and breast-feeding during the first 2 months at home either
exclusively (OR 5.1, 95% CI 1.6-16.4) or combined with infrequent exposure
to small amounts of cow's milk (OR 5.7, 95% CI 1.5-21.6). Fifty infants ha
d their first adverse symptoms during exclusive breast-feeding, and 32 infa
nts were sensitized during exclusive breast-feeding. Most of the infants in
both cases were IgE-positive: 37 and 23, respectively.
Conclusions In infants who are prone to developing cow's milk allergy, prol
onged breastfeeding exclusively or combined with infrequent exposure to sma
ll amounts of cow's milk during the first 2 months of life induces developm
ent of IgE-mediated response to cow's milk;.