Campylobacter Flashcards
What are the two main toxins used in campy pathogenesis
Cytolethal distending toxin (Cdt): causes G2 cell cycle arrest in cultured cells
Phospholipase (PldA): lyses erythrocytes
C. jejuni ss jejuni can be differentiated from ss doylei. Explain why
ss jejuni is resistant to cephalothin and sensitive to nalidixic acid
What are the methods of typing are used for the Campylobacter species
Pulse Field Gel Electrophoresis (PFGE)
Multi-locus Sequence Typing (MLST)
SNP Assays
Whole genome sequencing*
MALDI-ToF*
Campylobacter control strategies on farms
disinfections of poultry houses between flocks
use of chlorinated water for disinfection
strict biosecurity
The type of disease caused by Campylobacter species
Enteric Disease
The two species of campylobacter that cause bovine infertility
- C. fetus ss venerealis
- A skirrowii
In developed countries what are the peak incidence ages of Campylobacter infection?
0-4 years
20-24 years
Describe the treatment for a patient with a campylobacter infection.
Bed rest is the best option with IV to replace electrolytes and fluids
Second option is antibiotic therapy the first line being erythromycin, quinolones for increasing resistance and macrolides e.g azithromycin
Finally if resistant to the first line of antibiotics ciprofloxacin
Virulence/Bacterial factors that are responsible for Campylobacter invasion
Adhesins (CadF,CapA,PEB1,P95,JIpA)
Motility (polar flagella)
Secreted proteins (CiaB protein, T4SS, T6SS)
The 3 species of Campylobacter that cause ovine/bovine abortion.
C. fetus ss fetus
C. jejuni
Arcobacter cryoaerophila
Examples of future immunization strategies for campylobacter infections
Immunization
Bdelvibrio
Genetic Resistance
Bacteriophages
Campylobacter control strategies in home/restaurants
Correct handling of food to avoid cross contamination e.g separate cutting boards for veg and meat
Thorough cooking
Most human diseases associated with Campylobacter species are caused by
C.jejuni (80%)
C. coli (20%)
Most campy outbreaks occur in
the spring and autumn months
Campylobacter control strategies in processing
forced air chilling
good hygiene practices
scalding
organic acid treatment
Define Fastidious
Difficult to grow in a controlled environment due to complex nutritional and/or environmental requirements
Which Campylobacter species test negative for the Hipurate test
C.coli
What techniquesare used to isolate Campylobacter species from samples in the lab?
Selective Isolation (high temp-40c, microaerophilic O2 5%, CO2 10%, N2 85%)
Filtration (0.65 nm)
Pre-enrichment
Specialized Media [Rich, selective (Amphotericin B/CCDA)]
What are the 7 species of Campylobacter that cause human disease?
C. jejuni
C. coli
C. lari
C. upsaliensis
C. jejuni ss doylei
C. fetus
Arcobacter butzleri
Virulence Factors (def.)
The molecules that assist in bacterial colonization of the host at the cellular level
Sporadic campy infections occur in the summer due to
Men, barbeques
What are the four main symptoms of C. jejuni enteritis
Severe abdominal pain
Diarrhea (watery, watery w/blood, bloody low volume)
Fever
Nausea
List the major sources of Campylobacter infection in humans
Birds(chickens,pigeons)
Mammals (cows, pigs) : C.coli
Flys
Define septicemia
The presence of bacteria in the blood which is starting to spread to other areas in the body
Transport medium suitable for Campylobacter transport
Cary-Blair
What is a common contaminant in Campylobacter isolation plates
Pseudomonas aeruginosa
How should stool samples be stored
Chilled and submitted to a lab within 24 hrs
Airtight containers to prevent desiccation and minimize air exposure
Define bacteriaemia
The presence of of bacteria in the blood
The economic impact of Campylobacter infection
Days off from work
Hospitalization cost (2.4 billion euros a year)
Describe how hemolytic uremic syndrome can lead to kidney failure
Small blood vessels in the kidney become inflamed and damaged which can lead to blood clots. An excess of these blood clots can lead to kidney damage which if left untreated can lead to kidney failure
What symptoms are necessary for a patient to require antibiotics for a campy infection?
High fever
bloody diarrhea
excessive bowel movements 8+ times a day
Symptoms lasting more than a week
Pregnancy
Immunocompromised states (e.g AIDS)
What are the 5 pathogenic mechanisms campylobacter species use?
Toxins
Tissue invasion
Transcytosis
Molecular mimicry
Activation of host inflammatory mediators (IL-8, LTB4, PGE2)
Define pathogenesis
The origination and development of a disease
What are 6 examples of C. jejuni infection sequelae
Guillain Barre Syndrome (GBS)
Acute appendicitis
Reactive arthritis
Irritable Bowel Syndrome
Cholecystitis
Hemolytic Urine Syndrome
Define sequelae
A condition that was caused by a previous disease
How long is the incubation period of C. jejuni
1-7 days
Campylobacter species are pleomorphic and take on different shapes during their life, what are they?
Curved/seagull shaped: alive
Coccoid: moribund/dead
Straight rod: lab cultivated
