Enteropathogenic Escherichia coli serotype O111:HNT isolated from preterm neonates in Nairobi, Kenya.
This investigation was initiated as a consequence of several cases of diarrhea in a nursery ward for preterm babies in Nairobi, Kenya. Ten lactose-positive colonies were isolated from the stools of each of 30 neonates, regardless of whether they had diarrhea; 229 strains were identified as Escherichia coli and 65 strains were identified as Klebsiella pneumoniae. Six strains were lost during laboratory handling. No other bacterial, viral, or parasitic enteropathogens were identified. Using synthetic alkaline phosphatase-labeled probes, the bacterial isolates were found to be negative for the presence of genes coding for heat-stable and heat-labile enterotoxins. Seventy-eight E. coli strains isolated from a total of 13 neonates possessed the E. coli enteropathogenic adhesion factor (EAF) gene, as demonstrated by the use of a cloned radiolabeled DNA fragment probe. These strains possessed similar plasmid profiles constituting a core plasmid profile, and while all adhered to HeLa cells, none produced Vero cell cytotoxins. The EAF gene was located on a 65-megadalton plasmid. Serotyping showed the strains to be of serogroup O111 and serotype H nontypable, a well known enteropathogenic type. Five neonates died during the outbreak, and the fatality rate was 30.7% (4 of 13) for neonates infected with EAF-positive E. coli strains compared with 7.7% (1 of 13) for neonates from whom only EAF-negative E. coli strains were isolated. K. pneumoniae only was isolated from five neonates.
Senerwa
D
D
Department of Microbiology and Immunology, Norwegian College of Veterinary Medicine, Oslo.
Olsvik
O
O
Mutanda
L N
LN
Lindqvist
K J
KJ
Gathuma
J M
JM
Fossum
K
K
Wachsmuth
K
K
D018830:Adhesins, Escherichia coli; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics; D003428:Cross Infection / Q000382:microbiology*; D003603:Cytotoxins / Q000096:biosynthesis; D015342:DNA Probes; D004269:DNA, Bacterial / Q000032:analysis; D003968:Diarrhea, Infantile / Q000382:microbiology*; D004768:Enterotoxins / Q000235:genetics; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D004927:Escherichia coli Infections / Q000382:microbiology*; D029968:Escherichia coli Proteins; D005243:Feces / Q000382:microbiology; D006367:HeLa Cells; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000382:microbiology*; D007630:Kenya; D007711:Klebsiella pneumoniae / Q000302:isolation & purification; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D012703:Serotyping; D022622:Shiga Toxin 1
D018830:Adhesins, Escherichia coli; D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D003603:Cytotoxins; D015342:DNA Probes; D004269:DNA, Bacterial; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D022622:Shiga Toxin 1; C034151:heat stable toxin (E coli); C027538:heat-labile enterotoxin, E coli