Serum immunoglobulin levels in newborn infants. II. Survey of cord and follow-up sera from 123 infants with congenital rubella

The value of determining serum immunoglobulin levels as a screening test for intrauterine infection was evaluated in 123 infants with documented congenital rubella and in control subjects. Data collected from cord blood and from specimens obtained during the first 36 months of life were submitted to statistical analysis. Elevation of cord IgM values (20 mg. per cent or above) was noted in only 18 per cent of infants with rubella, and principally in those who had the more severe and usually clinically recognized manifestations of congenital rubella. Immunoglobulin values in sera collected during the first 6 months of life were elevated in approximately half of the infants tested and in those with mild illness as commonly as those with severe illness.