enterobacteria

• E. tarda


  Most frequently isolated species of Edwardsiella in clinical specimens
• E. tarda


  • Associated with gastroenteritis (most common presentation)
• Salmonella infections


  • Typhoidal salmonellae
  • Non-typhoidal salmonellae or NTS
• Typhoidal salmonellae


  Gastrointestinal infection
• Non-typhoidal salmonellae or NTS

  Blood stream infection
• Typhoidal salmonellae


  • Salmonella typhi
  • Salmonella paratyphi
• Non-typhoidal salmonellae


  Salmonella enterica
• Yersinia Infections


  • Yersinia Pestis
  • Y. enterocolitica
  • Y. pseudotuberculosis
• Yersinia Pestis


  Causative agent of Plague
• Plague


  Transmitted from rodents by arthropod vector (the rat flea)
• Important shigella species


  • S. dysenteriae
  • S. flexneri
  • S. boydii
  • S. sonnei
• Shigella


  Important cause of bacillary dysentery
• Minimum infective dose for shigella infection

  As low as 10 -100 bacilli
• Toxins produced by shigella

  • Shigella enterotoxin
  • Shiga toxin
  • Endotoxin
• Cases caused by S. dysenteriae type-1

  Associated with high mortality
• Shigellosis


  The most communicable disease among bacterial causes of diarrhea
• Enrichment broth for salmonella and shigella

  • Selenite F broth
  • tetrathionate broth
• Selective media for salmonella and shigella


  • DCA Agar (Deoxycholate Citrate Agar)
  • XLD Agar (Xylose Lysine Deoxycholate Agar)
• Shigella


  Catalase positive (except S.dysenteriae serotype-1)