[Interferon alpha production in the serum of very young infants after viral infections]

IFN-alpha detection is useful in some clinical circumstances, but its use has never been validated in young infants with viral infections.The authors wanted to determine it there was any difference in the assessment of IFN-alpha production between infants under or over six months of age.A series of 233 children with identified common viral infections who had been assessed for IFN-alpha production was retrospectively analyzed. The viral infections were enteroviral meningitis (n =103), respiratory syncytial virus infections (n =60), and rotavirus gastroenteritis (n =70). Data collected from the group of infants under six months of age (n =105) was compared to that of the older children (n =128). Qualitative and quantitative values of interferon-alpha were determined for each group.Interferon-alpha was detected in very young infants (81.9% of cases) as often as in the older age group (80.3% of cases), for any of the three viral infections (P =0.3-0.63). The mean level of interferon-alpha production detected was not lower in the youngest group, and even higher in the group under six months of age with enteroviral meningitis.Interferon-alpha detection in very young infants is efficient and may be useful to differentiate between viral and bacterial infection particularly when the etiological diagnosis appears uncertain.