gram positive rods

• medically important gram-positive rods

  • Corynbacterium spp.
  • Bacillus spp.
  • Listeria monocytogenes
• bacillus species

  • bacillus is one of the two species that forms endospores
  • non-anthracis species
  • ubiquitous in the environment
  • may transiently colonize skin and contaminate blood cultutes
  • exception: mult positive blood cxs w/ same organism
  • less commonly associated w/ infections of foreign bodies or intravascular catheters
  • bacillus antracis
  • causes anthrax
  • best known as a form of bioterrorism
• Corynebacterium species

  • ubiquitous colonizers
  • commonly contaminate blood cultures --> no treatment needed
  • exception: pts w/ multiple positive cultures
  • another important (but very rare) exception: C. diphtheriae --> diphtheria exotoxin
• listeria monocytogenes

  • transmitted by consumption of contaminated food --> CDC reportable outbreaks
• • no antibiotics
  • healthy adults
  • gastroenteritis related symptoms
  • drug of choice: ampicillin or penicillin
  • elderly
  • elderly or immunocompromised pts may develop more invasive disease such as sepsis or meningitis
  • pregnancy
  • pregnant women typically develop mild flu-like illness
  • however, the infection can spread to the fetus and cause miscarriage, stillbirth, premature delivery, and neonatal sepsis