Aeromonas species

• AEROMONAS

  • Enterobacteriaceae family
• Aeromonas

  - Enterobacteriaceae family

  - Enteric bacilli

  - Enteric gastrointestinal bacteria

  - Oxidase positive, glucose fermenting, gram negative rods

  - Grows well on BAP - B hemolytic
• Vibrio spp., Aeromonas spp., Pleisiomonas spp.

  • Non-enteric gastrointestinal bacterial
  • Not part of the normal flora; commonly found in the environment
  • Pleisiomonas spp. is part of the Enterobacteriaceae family and is oxidase positive
• Aeromonas

  - A. caviae : cause of gastroentritis, ranging from watery diarrhea (most common) to dysentery-like ilness [has blood, mucus, pus]

  - A. hydrophilia: cause of wound infections; traumatic soft tissue injuries (described in patients with hematologic malignancies [leukemia, anemia], and liver disease)

  TOC: third generation cephalosporins, azteromam, carbapenems as well as aminoglycosides
• INTESTINAL INFECTIONS

  • Acute secretory diarrhea - often accompanied by vomiting
  • Acute dysenteric form of diarrhea - similar tp shigellosis, with blood and mucus
  • Chronic diarrhea - usually last for more than 10 days
  • Cholera like disease - including rice water stools
  • Nebulous syndrome - commonly referred to as travelers diarrhea (pediatric and immunocompromised patients)
• EXTRAINTESTINAL INFECTIONS

  • Septicema
  • Wound infections - meningitis, osteomyelitis, otitis, cystitis keratitis etc.
• A. caviae

  • gastrointestinal infections, especially in neonate and pediatric populations
  • has been associated with inflammatory bowel disease.
• A. hydrophilia

  • most common species that can cause human gastroenteritis
• A. veronii biovar sobria; veronii

  • hemolytic-uremic syndrome or kidney disease that might require kidney transplantation
• A. veronii boviar sobria

  • linked to cholera-like disease characterized by abdominal pain, fever, and nausea.
• Culture media: A. caviae

  • SBA – strong B-hemolysis
  • hydrophila, A. veronii biovar sobria, and A. jandaei
  • MAC – Ferments lactose
  • Modified cefsulodin Irgasin-novobiocin (CIN) II plate
  • CIN Medium
• Presumptive identification : A. caviae

  • Oxidase Test: (Aeromonas = positive)
  • Spot indole test [positive]
  • Ability to grow in the presence of NaCl
  • String Test [negative]