Increased cell adherence of group B streptococci from preterm infants with neonatal sepsis

Most women with group B streptococcus cervical colonization have uncomplicated pregnancies, but about 1% experience preterm premature rupture of membranes (PROM) followed by neonatal group B streptococcal sepsis. In such cases, streptococcal adherence to and penetration of the membranes may be an important step in the pathogenesis. In the present study, chorionic epithelial cells were incubated with group B streptococci isolated from either children developing sepsis after preterm PROM (complicated pregnancies) or from uncomplicated pregnancies. Incubation periods varied. The numbers of adherent bacteria per chorionic epithelial cell were counted by microscopic examination. After 70 minutes' incubation, the number of adherent group B streptococci in complicated pregnancies was 38, compared with 14 in uncomplicated pregnancies (P less than .001). This difference in vitro might reflect the virulence of group B streptococci.