Chalter 34: Campylobacter and Helicobacter spp. Flashcards
Shape
-Slender, curved, rods
-gull-winged and spiral forms
Motility
Motile with polar flagella
Type of bacteria
Gram-negative
Size
0.2 to 0.5 um
Daughter cells appearance
-Gull-winged
-long spirals (formed by joined cells)
Environment
Microaerophilic
Requirement
-fastidious
-enriched media with
-atmosphere of increased CO2 and decreased oxygen tension
MacConkey agar
Many spp. grow on MacConkey agar
-oxidase
-catalase
-Fermentation
-positive
-variable
-non-fermentative
Found in
-Intestinal tracts of domestic animals
-Genital tracts of domestic animals
Principal disease conditions:
Either:
-intestinal (presenting as diarrhea)
-genital (infertility or abortion)
Previously classified in the genus
Vibrio
Term ‘vibriosis’ retained for some disease in Campylobacter
Spp. of vet importance:
-C. fetus subsp. venerealis
-C. fetus subsp. fetus
-C. jejuni subsp. jejuni
Established human pathogen. May have zoonotic potential
Order: Campylobacterales
Genus: Helicobacter
Specie: H. pylori
Usual habitat
Commensals in the intestinal tracts of warm-blooded animals
-Colonize intestines of birds
-Results in fecal contamination of water courses and stored food
-Campylobacter jejuni
-Campylobacter lari
Many Campylobacter is excreted in feces
Adapted principally to bovine preputial mucosa
Campylobacter fetus subsp. venerealis
Campylobacter are strictly microaerophilic
Atmosphere requirement
: 5 to 10% oxygen
: 1 to 10% CO2
Primary isolation
Skirrow agar (selective enriched medium)
Differentiation is based on:
-colonial morphology
-certain cultural,
-biochemical,
-antibiotic-susceptibility characteristics
-phenotyping methods are also increasingly used
Colonial morphology:
-C. fetus subsp. venerealis
-C. fetus subsp. fetus
-small, round, smooth, translucent colonies
-with dewdrop appearance
Colonial morphology:
-C. jejuni
-small, flat, grey colonies
-with a spreading, watery appearance
Some Campylobacter are slightly pigmented
Campylobacter do not ferment carbohydrates
Pathogenesis and pathogenicity
-C. fetus subsp. venerealis
-C. fetus subsp. fetus
-structurally unusual
-Posses a micro capsule or S layer
Arranged in lattice formation
Microcapsule or S layer
S layer confers resistance to
-serum-mediated destruction
-phagocytosis
-enhances survival in the genital tract
Major outer membrane protein that acts as an adhesin found in:
-C. jejuni
-C. fetus subsp. fetus
-C. fetus subsp. venerealis
Other genes encoding adhesion proteins such as:
-cadF (Campylobacter adhesion to fibronectin)
Flagellar genes also identified
-internalized into epithelial cells following adhesion
-may replicate within the membrane-bound compartment
-then released by exocytosis from basolateral surface
C. jejuni (intestinal pathogen)
Cytolethal distending toxin identified in:
-C. jejuni
-C. fetus
Has particular tropism for bovine host
C. fetus subsp. venerealis
Contains genes encoding the components of a_____
Type IV secretion system
Has also heat stable endotoxin
Pathogenesis is uncertain
Infertility
-Cattle
-caused by C. fetus subsp. venerealis
Abortion
-Ewes
-caused by C. fetus subsp. fetus” or by “C. jejuni
Bovine genital campylobacteriosis
-etiology
-transmission
-C. fetus subsp. venerealis
-coitus
Ovine genital campylobacteriosis
-etiology
-transmission
-C. fetus subsp. fetus or (faeces of cattle and sheep)
-C. jejuni (faeces of wide range of birds and mammals)
-fecal-oral route
-Intestinal campylobacteriosis in dogs
-Avian vibrionic hepatitis
-Intestinal campylobacteriosis in humans
-
-C. jejuni
-C. jejuni
Helicobacter
-shape
-type of bacteria
-size
-requirement
-environment
-saccharolytic?
-oxidase
-catalase
-helical, S-shaped or curved, rods
-Gram-negative rods
-(3.0 x 0.5 to 0.9 um)
-enriched media; some grow on Skirrow’s agar
-microaerophilic
-non-saccharolytic
-positive (except *H. canis)
-positive
Helicobacter found in
Gastric mucosa and others are found in the intestine of humans and animals including both domestic and wild animals and birds
Characteristic of Helicobacter which colonize the gastric mucosa
A strong urease reaction
H. pylori human pathogen associated with
-gastric ulcers
-gastric adenocarcinoma
-mucosa-associated lymphoid tissue (MALT) lymphoma
H. pylori human pathogen associated with many disease morphology
Slightly curved
Non-H. pylori helicobacters morphology
Long and spiral-shaped
Helicobacter is associated with gastritis in
-pigs
-cats
-dogs
-associated with sheep abortion
-noe thought to compromise several Helicobacter species
‘Flexispira rappini’
Morphology of ‘Flexispira rappini’
-Distinctive
-spindle-shape
-gram negative bacteria
-with periplasmic fibres
-and bipolar tufts of sheathed flagella
Catalase production postive
Except:
-C. mucosalis
-C. sputorum* biovar Sputorum
Growth at 25 degree celcius
-C. fetus subsp. venerealis
-C. fetus subsp. fetus
-C. hyointestinalis
Growth at 42 degrees celcius
Except:
-C. fetus subsp. venerealis
-C. fetus subsp. fetus
Growth in 1% glycine
All except:
-C. fetus subsp. venerealis (some strains are glycine tolerant and are designated C. fetus subsp. venerealis biovar Intermedius
Growth in 3.5% NaCl
Only:
-C. sputorum biovar Sputorum
Positive for production of H2S (lead acetate method of detection)
All except:
-* C. fetus* subsp. venerealis
Susceptibility to Nalidixic acid (30 ug discs)
Resistant except:
-C. fetus subsp. fetus: (V)
-C. jejuni subsp. jejuni: (S)
-C. coli: (S)
Susceptibility to Cephalothin (30 ug discs)
Only resistant:
-C. jejuni subsp. jejuni
-C. lari
-C. coli
Table 34.1
Figure 34.2
Figure 34.3
