Staphylococcus epidermidis

Definition

Staphylococcus epidermidis is a Gram-positive, coagulase-negative bacterium that is a common member of the normal human skin and mucous membrane microbiota. It is considered an opportunistic pathogen, capable of causing infections in immunocompromised individuals or when the skin barrier is breached.

5 Must Know Facts For Your Next Test

1. Staphylococcus epidermidis is the most abundant and prevalent species of coagulase-negative staphylococci found on human skin and mucous membranes.
2. It plays a beneficial role in maintaining the skin's natural defenses by competing with more pathogenic microorganisms and producing antimicrobial compounds.
3. Staphylococcus epidermidis can form biofilms on medical devices, such as catheters and prosthetic implants, leading to device-related infections.
4. The ability of Staphylococcus epidermidis to produce a slimy extracellular matrix and use quorum sensing to coordinate its behavior contributes to its virulence in these types of infections.
5. While generally considered a low-virulence pathogen, Staphylococcus epidermidis can cause opportunistic infections in immunocompromised individuals or when the skin barrier is disrupted.

Review Questions

• Describe the role of Staphylococcus epidermidis in the normal microbiota of the skin and eyes.
  • Staphylococcus epidermidis is a common and abundant member of the normal microbiota of the skin and eyes. It plays a beneficial role in maintaining the skin's natural defenses by competing with more pathogenic microorganisms and producing antimicrobial compounds. As part of the normal microbiota, Staphylococcus epidermidis helps to prevent the overgrowth of potentially harmful bacteria and contributes to the overall health and integrity of the skin and eye tissues.
• Explain how Staphylococcus epidermidis can become an opportunistic pathogen and cause infections, particularly in the respiratory tract.
  • While Staphylococcus epidermidis is generally considered a low-virulence pathogen, it can cause opportunistic infections in individuals with compromised immune systems or when the skin or mucosal barriers are disrupted. In the respiratory tract, Staphylococcus epidermidis may opportunistically colonize and cause infections, particularly in individuals with underlying respiratory conditions or those who have undergone invasive medical procedures, such as intubation or the use of respiratory devices. The ability of Staphylococcus epidermidis to form biofilms and use quorum sensing to coordinate its behavior can contribute to its virulence in these types of infections.
• Analyze the potential impact of Staphylococcus epidermidis infections on patient outcomes, particularly in the context of medical device-related infections.
  • Staphylococcus epidermidis infections, particularly those associated with medical devices, can have a significant impact on patient outcomes. The bacterium's ability to form biofilms on the surfaces of implanted devices, such as catheters and prosthetic implants, can lead to persistent and difficult-to-treat infections. These biofilm-associated infections are often more resistant to antimicrobial agents and the host immune response, increasing the risk of complications, prolonged hospital stays, and even life-threatening consequences for the patient. Understanding the mechanisms by which Staphylococcus epidermidis can cause these device-related infections and developing strategies to prevent and manage them are crucial for improving patient outcomes and reducing the burden of healthcare-associated infections.

Related terms

Coagulase-negative Staphylococci (CoNS): A group of Staphylococcus species that do not produce the enzyme coagulase, which distinguishes them from the more pathogenic Staphylococcus aureus.

Biofilm: A complex community of microorganisms embedded in a self-produced extracellular matrix that adheres to surfaces, making them more resistant to antimicrobial agents and the host immune response.

Quorum Sensing: A cell-to-cell communication process that allows bacteria to coordinate their gene expression and behavior in response to changes in cell population density.