Cronobacter Support
04-29-2009, 02:25 PM
1st International Conference on Cronobacter Poster Abstract 15
Comparative virulence of Cronobacter and Enterobacter species with Citrobacter koseri and Escherichia coli k1.
A number of Enterobacteriaceae are associated with neonatal infections, of particular interest are Escherichia coli K1, Cronobacter spp., and Citrobacter koseri which may cause infant meningitis. Other organisms of concern include Enterobacter cloacae, E. hormaechei, and Salmonella serovars. 29 strains of Cronobacter spp., Ent. cloacae, Ent. hormaechei, Cit. freundii, Cit. koserii, Salmonella serovars and E. coli K1 was studied. The virulence potential was assessed using attachment and invasion assays of human intestinal cell lines, macrophage survival, and invasion of human and rat brain cell lines. Ent. cloacae showed the highest attachment (3.5% inoculum) to human intestinal cells, but Salm. Enteritidis had the highest invasion rate (0.4% inoculum). One Cr. sakazakii strain (associated with a fatal neonatal meningitis case) showed significantly greater invasion rates (0.25%) of intestinal cells than other Cronobacter strains (0.05-0.2%) and other Enterobacteriaceae, except Salmonella Enteritidis. The survival of Cronobacter in macrophages varied considerably, with Cr. sakazakii persisting longer than other Cronobacter species. Similarly, Cit. koseri persisted in macrophages for up to 48 hours. Cit. koseri showed the highest invasion of rat brain capillary endothelial cells (2.5% inoculum), the second highest was the meningitic strain of Cr. sakazakii (1.6%). Cit. freundii, Ent. cloacae, and Ent. hormaechei showed similar rates for all assays as the non-meningitic strains of Cronobacter. The virulence potential of Cronobacter isolates varies according to species. Clinical outcome of infection as yet cannot be predicted using in vitro tissue culture assays. Discrepancies will occur as the immune status, and neonate exposure is unknown.
Juncal Caubilla-Barron, Mike Loughlin, Stacy Townsend, Edward Hurrell and Steve Forsythe
School of Biomedical and Natural Sciences, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, United Kingdom.
Comparative virulence of Cronobacter and Enterobacter species with Citrobacter koseri and Escherichia coli k1.
A number of Enterobacteriaceae are associated with neonatal infections, of particular interest are Escherichia coli K1, Cronobacter spp., and Citrobacter koseri which may cause infant meningitis. Other organisms of concern include Enterobacter cloacae, E. hormaechei, and Salmonella serovars. 29 strains of Cronobacter spp., Ent. cloacae, Ent. hormaechei, Cit. freundii, Cit. koserii, Salmonella serovars and E. coli K1 was studied. The virulence potential was assessed using attachment and invasion assays of human intestinal cell lines, macrophage survival, and invasion of human and rat brain cell lines. Ent. cloacae showed the highest attachment (3.5% inoculum) to human intestinal cells, but Salm. Enteritidis had the highest invasion rate (0.4% inoculum). One Cr. sakazakii strain (associated with a fatal neonatal meningitis case) showed significantly greater invasion rates (0.25%) of intestinal cells than other Cronobacter strains (0.05-0.2%) and other Enterobacteriaceae, except Salmonella Enteritidis. The survival of Cronobacter in macrophages varied considerably, with Cr. sakazakii persisting longer than other Cronobacter species. Similarly, Cit. koseri persisted in macrophages for up to 48 hours. Cit. koseri showed the highest invasion of rat brain capillary endothelial cells (2.5% inoculum), the second highest was the meningitic strain of Cr. sakazakii (1.6%). Cit. freundii, Ent. cloacae, and Ent. hormaechei showed similar rates for all assays as the non-meningitic strains of Cronobacter. The virulence potential of Cronobacter isolates varies according to species. Clinical outcome of infection as yet cannot be predicted using in vitro tissue culture assays. Discrepancies will occur as the immune status, and neonate exposure is unknown.
Juncal Caubilla-Barron, Mike Loughlin, Stacy Townsend, Edward Hurrell and Steve Forsythe
School of Biomedical and Natural Sciences, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, United Kingdom.