NEONATAL IGA AND IGE LEVELS AMONG INFANTS WITH PATERNAL HEREDITY FOR ATOPIC DISEASE

Serum IgA and IgE levels were studied in the postnatal period in 21 in fants having a paternal heredity of atopic disease. Three different sa mpling techniques were used, aspirated cord blood (CB), gravity-collec ted cord blood, and capillary collected blood at 4-5 days of age. Sign ificant differences among the three sampling techniques were recorded for IgA (P < 0.01), but not for IgE. The IgA levels decreased from bir th to 4-5 days of age in 90% (19/21) of the infants (P < 0.01). The co rresponding decrease in IgE levels was 20%. This postnatal difference in the frequency of decreasing/increasing IgA and IgE levels was signi ficant (P < 0.05). An analysis of CB IgA to detect maternal contaminat ion of CB was found to be of questionable value, since only 50% (2/4) of the cases with an elevated CB-IgA level could be considered contami nated. The results of this study further emphasize that aspiration of CB and capillary collection of blood at 4-5 days of age are the best s ampling techniques to avoid contamination. The general finding that pa ternal heredity had no significant influence on infant IgE contrasts w ith the strong influence of maternal heredity. Further studies will sh ow whether the explanation lies in genetic or transplacental factors, or in both kinds of factors.