Bacteria

Staphylococcus Epidermidis

search

Staphylococcus Epidermidis

  • See Also
  1. Staphylococcus
  • Labs
  • Characteristics
  1. Shares common appearance with other Staphylococci
    1. Gram Positive Cocci in irregular clusters
    2. Facultative Anaerobes
    3. Beta hemolytic
      1. As with Beta Hemolytic Streptococcus, hemolyze RBCs on sheep blood agar plate (BAL)
    4. Catalase positive
      1. Catalase converts Hydrogen Peroxide (from Macrophages, PMNs) into water and oxygen
      2. Catalase positive organisms on a culture plate will bubble when exposed to Hydrogen Peroxide
  2. Unique Staphylococcus Epidermidis features
    1. Coagulase-Negative Organisms
      1. Contrast with the coagulase positive Staphylococcus Aureus
    2. Adherent Polysaccharide capsule
      1. Polysaccharide capsule adheres well to catheters and prosthethic devices
      2. Most common colonizer of tubes and devices (and related secondary infections)
      3. Staphylococcus Epidermidis commonly forms a biofilm around these devices
  • Pathophysiology
  1. Normal Bacterial colonization of human skin
    1. Frequently contaminates Blood Cultures
  2. Infects catheters and lines
    1. Catheter Associated Urinary Tract Infection
    2. Central Line-Associated Bloodstream Infection
  3. Prosthetic Infections
    1. Prosthetic Joint Infection
    2. Prosthetic Valve Endocarditis
    3. Peritoneal Dialysis Catheter Infections
  • References
  1. Otto (2009) Nat Rev Microbiol 7(8):555-67 +PMID: 19609257 [PubMed]