Total IgE and specific IgG levels to beta-lactoglobulin and ovalbumin and allergy outcome in small for gestational age infants: A pilot study

Total IgE and specific IgG levels to beta-lactoglobulin and ovalbumin and a llergy development were investigated in 22 small for gestational age (SGA) infants monitored for 12 months. A high incidence of allergy was observed a t 12 months corrected age relative to published reports on appropriate for gestational age infants. This was particularly noticeable in infants from a nonatopic background, where 56% (5/9) were allergic, as well as in infants with a family history of atopy, where 85% (11/13) were diagnosed as allerg ic at 12 months corrected age. There was a nonsignificant (NS) trend for to tal serum IgE levels to increase with age in infants from both atopic and n onatopic backgrounds. Levels of beta-lactoglobulin IgG peaked at 4 months c orrected age in both groups and had decreased by 12 months corrected age, r eflecting the induction of tolerance (median and range, 4 months corrected age vs. 12 months corrected age; atopic: 904 (8-3437) mu g/ml vs. 449 (53-3 200) mu g/ml, p < 0.02; nonatopic: 836 (39-1473) mu g/ml vs. 503 (85-1914) mu g/ml, p = NS). Ovalbumin IgG antibody levels decreased between 40 weeks gestational age and 4 months corrected age (atopic: 66 (9-382) mu g/ml vs. 33 (6-599) mu g/ml, p = NS; nonatopic: 40 (8-1026) mu g/ml vs. 16 (7-62) mu g/ml, p < 0.05) before reaching their highest level at 12 months corrected age [atopic: 551 (17-3147) mu g/ml, both 40 weeks gestational age and 4 mo nths corrected age vs. 12 months corrected age, p < 0.005; nonatopic: 286 ( 13-1791) mu g/ml, p = NS]. These changes reflect the degradation of materna l IgG in the infant and lack of egg in the early diet, followed by the intr oduction of egg products during weaning. This finding of a high allergy inc idence in SGA infants should be further investigated.