An improved selective medium for the isolation of Escherichia coli O157.
Sorbitol-MacConkey medium has become widely used for the isolation of verotoxigenic (VT+) Escherichia coli O157. However, many organisms other than VT+ E. coli O157, especially other serogroups of E. coli and Proteus spp., may not ferment sorbitol, and thus may be confused initially with VT+ E. coli O157. Rhamnose is not fermented by VT+ E. coli O157, but is by most sorbitol non-fermenting E. coli of other serogroups. Cefixime is a cephalosporin antibiotic that is more active against Proteus spp. than against E. coli. Inclusion of rhamnose and cefixime in sorbitol-MacConkey agar improves its selectivity for the isolation of VT+ E. coli O157.
Chapman
P A
PA
Public Health Laboratory, Northern General Hospital, Sheffield.
Siddons
C A
CA
Zadik
P M
PM
Jewes
L
L
D000892:Anti-Infective Agents, Urinary / Q000494:pharmacology; D001427:Bacterial Toxins; D020682:Cefixime; D002439:Cefotaxime / Q000031:analogs & derivatives / Q000494:pharmacology; D003470:Culture Media / Q000494:pharmacology; D003967:Diarrhea / Q000382:microbiology; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D012210:Rhamnose / Q000494:pharmacology; D022622:Shiga Toxin 1
D000892:Anti-Infective Agents, Urinary; D001427:Bacterial Toxins; D003470:Culture Media; D022622:Shiga Toxin 1; D020682:Cefixime; D002439:Cefotaxime; D012210:Rhamnose