Non-Enteric Gastrointestinal Pathogens: Vibrio Species

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What type of flagella do Vibrio spp. have?

  • Peritrichous flagella
  • Lophotrichous flagella
  • Amphitrichous flagella
  • Monotrichous flagella (correct)

What is the purpose of adding salt to the growth medium of Vibrio spp.?

  • To differentiate between Vibrio spp. and Aeromonas spp.
  • To identify the species of Vibrio
  • To inhibit the growth of contaminants
  • To stimulate the growth of the bacteria (correct)

What is the characteristic appearance of Vibrio spp. under direct microscopy?

  • Thread-like
  • Comma-shaped
  • Fish in stream (correct)
  • Rods in a bundle

Which of the following is a characteristic of V. parahaemolyticus?

<p>Associated with the 'Kanagawa phenomenon' (C)</p> Signup and view all the answers

What is the purpose of the string test in the biochemical identification of Vibrio spp.?

<p>To detect the presence of urease enzyme (C)</p> Signup and view all the answers

Which of the following Vibrio spp. is associated with ear infections and wound infections?

<p>V. alginolyticus (D)</p> Signup and view all the answers

What is the primary mode of transmission of Vibrio cholerae?

<p>Ingestion of contaminated water or food (D)</p> Signup and view all the answers

What is the toxin responsible for the symptoms of cholera?

<p>Cholera toxin (choleragen) (C)</p> Signup and view all the answers

Which of the following is a characteristic of Vibrio cholerae colonies on BAP?

<p>Large, round, raised, and beta hemolytic (C)</p> Signup and view all the answers

Which Campylobacter species is associated with abortion in animals?

<p>C.fetus (A)</p> Signup and view all the answers

What is the characteristic shape of Campylobacter spp.?

<p>Curved, S-shape or sea-gull's wing (C)</p> Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Vibrio Spp.

  • Ubiquitous, curved, gram-negative rods, non-sporeformers, motile with monotrichous flagella
  • Oxidase positive, growth is stimulated in the presence of salt (halophilic) except for V.cholerae and V.mimicus
  • Laboratory diagnosis:
    • Direct microscopy: "fish in stream" appearance
    • Culture: enrichment broth (APW), translucent colonies on MAC, and yellow colonies on TCBS
    • Biochemical ID: catalase and oxidase positive, string test positive

Vibrio Cholerae

  • Salt requirement: non-halophilic
  • Virulence factors: polysaccharide capsule, urease enzyme (in few strains)
  • TCBS: green colonies (sucrose NF)
  • Swarming on BAP
  • Associated with "Kanagawa phenomenon"
  • Serogroups: O1, O139, Non-O1/O139
  • V.cholerae O1 serotype: Inaba (Philippines), Ogawa (India), Hikojima (Japan)
  • V.cholerae O1 biotype: Classical, El Tor

Vibrio Parahaemolyticus

  • Salt requirement: halophilic
  • First reported in Japan to cause large food poisoning outbreak ("Summer diarrhea")
  • Virulence: polysaccharide capsule, urease enzyme (in few strains)

Vibrio Vulnificus

  • Causes wound infections and septicemia, involvement in gastroenteritis is uncertain
  • Lactose fermenter

Vibrio Alginolyticus

  • Causes ear infections, wound infections, and rare cause of septicemia
  • Transmitted via exposure of wound to contaminated water

Aeromonas Spp.

  • Ubiquitous, oxidase-positive, glucose-fermenting, gram-negative rods
  • Virulence factors: cholera toxin (choleragen), Zonula occludens toxin, toxin coregulated pili
  • Causes: "Rice watery stool" diarrhea, gastroenteritis, wound infections, bacteremia, HUS (Shiga-like toxin)
  • Growth is not stimulated by NaCl
  • BAP: large, round, raised, opaque, beta hemolytic colonies

Campylobacter Spp.

  • Motile (monotrichous), nonsporing, microaerophilic, curved gram-negative rods
  • S-shape/ Sea-gull's wing appearance
  • Causes: Diarrhea and gastroenteritis in humans (C.jejuni, C.coli, C.upsaliensis, C.lari, C.hyointestinalis)
  • Causes: Abortion in animals (C.fetus)
  • Triggers the pathogenesis of various other diseases such as Guillain-Barré syndrome (C.jejuni)

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

More Like This

Use Quizgecko on...
Browser
Browser