[Vertically transmitted bacteremias: to treat or not to treat?]

To analyze the incidence, etiology and management of infants born in 1977 with vertically transmitted bacteremia or suspected early neonatal sepsis.

The total number of newborn infants in this period was 2,365. We revised the clinical histories of the infants diagnosed with bacteremia and classified them into two groups: a) those with vertically transmitted bacteremias, according to the recommendations of the Castrillo Group, and b) those with suspected early onset neonatal sepsis in whom blood culture was positive and analytical data suggested bacterial infection but who showed no clinical symptoms of vertically transmitted sepsis. Birthweight, sex, gestational age, risk factors for neonatal infection, clinical signs and laboratory tests suggestive of bacterial infection and microbiological agents were analyzed. The clinical and analytical evolution of the treated and untreated newborn infants was studied.

The newborn infants were diagnosed with vertically transmitted bacteremia (an incidence of 4.2x1,000 live newborn infants) and 17 were diagnosed with suspected early onset neonatal sepsis (7.8x1,000 live newborns). All the infants had risk factors for neonatal sepsis. The most common of them was prolonged membrane rupture (>- 18 hours) due to which sepsis screening was carried out (hemogram, C-reactive protein at 12 and 36-48 hours of life, and blood culture). In both groups the most commonly isolated microorganism was group B streptococcus, which was found in 30% of vertically transmitted bacteremias and in 41.2% of suspected early onset neonatal sepsis. All the newborn infants with suspected sepsis and two with vertically transmitted bacteremia were treated without incident. The remaining eight infants with untreated vertically transmitted bacteremia were followed-up clinically ana analytically for one year, and remained asymptomatic.

The most common microorganism in vertically transmitted bacteremia and suspected early onset neonatal sepsis was group B streptococcus. None of the untreated infants developed late sepsis or meningitis. Our findings suggest that non-treatment of asymptomatic infants with vertically transmitted bacteremias is appropriate as long and close clinical surveillance is maintained.