Helicobacter Pylori

• How can Helicobacter Pylori be characterized?


  • Slightly helical, motile bacterium that colonizers stomach of its host
  • urease positive: essential for colonizing the stomach -> degrades urea to produce ammonia which neutralizes stomach acid
• What does Helicobacter Pylori cause?


  • gastritis and most peptic ulcers (erosions of the mucus membrane of the stomach or small intestine)
  • Long-term infections are a significant risk factor for stomach cancer
• What virulence factors does Helicobacter produce that enable it to colonize the stomach?


  • Proteins: inhibits acid production in stomach (decreases acid)
  • Flagella: help the pathogen to burrow through stomach lining
  • Adhesins: facilitate binding to gastric cell
  • Exotoxins: Cytotoxin- associated gene A product
  • CagA -> destroys epithelial cells in stomach lining -> peptic ulcers
  • Enzymes: Urease- helps neutralize stomach acid
• What is the portal of entry for Helicobacter?


  • Mouth
• How can Helicobacter be diagnosed?


  • Presence of H. Pylori can be demonstrated by positive urease test
  • biochemical tests provided a definitive identification
• How can H. Pylori be treated?


  • antimicrobial drugs in combination with drugs that inhibit acid production
• How can H. Pylori be prevented?


  • Good Hygiene
  • Adequate sewage treatment
  • Proper food handling