Campylobacterand Helicobacter Clinical Microbiology Review 191
ORGANISM PATHOGENICITY GRAM STAIN CULTURE KEY CHARACTERISTICS
Campylobacter jejuni
Campylobacter coli
Campylobacter fetus
Helicobacter pylori
Darting corkscrew
motility. Oxidase,
catalase, & hippurate
hydrolysis pos.Rarely differentiated
from C. jejuni.Hippurate
hydrolysis neg.Oxidase & catalase pos.
Hippurate hydrolysis neg.Rarely cultured. Rapid
urease tests on gastric
biopsy, urea breath test,
histology, PCR, serology.Most common cause of
bacterial diarrhea. Sources
of infection: chickens, raw
milk, petsSimilar to C. jejuni, but less
severe. Usually foodborneCauses bacteremia in im-
munocompromised & elderly.
Uncommon stool isolateGastritis, duodenal & peptic
ulcers. Possible risk factor for
gastric carcinomaCurved, slender, GNR.
“Seagulls,” loose
spirals, & S shaped.
Stain faintly.Same as above.Same as above.Curved, slender, GNR.Microaerophilic &
capnophilic. Grown on
Campy-BAP at 42°C in ↑
CO 2. (Can grow at 37°C;
normal enteric flora in-
hibited by 42°C incuba-
tion.) Slow growing. Hold
plates 3 days.Same as above.Most often isolated in
blood cultures. Hold for
2 wk. Inhibited on Campy
agar. Grows on routine
media at 37°C, not at 42°C.Grows on nonselective
media incubated at 37°C
in same atmosphere as
Campy. Doesn’t grow at
42 °C. Slow growing.