Which organism is known for producing slime?

Staphylococcus epidermidis is the Primary Slime-Producing Organism

Staphylococcus epidermidis is the organism known for producing slime, making option C the correct answer. According to the American Heart Association guidelines, S. epidermidis is characterized by its ability to produce extracellular slime that forms biofilms on implanted devices and medical materials 1.

Understanding Slime Production in Staphylococci

Slime production is a key virulence factor that allows bacteria to:

1. Form biofilms: The layers of bacteria on surfaces are encased in extracellular slime, constituting a biofilm 1
2. Adhere to surfaces: Slime mediates adherence to medical devices and prosthetic materials
3. Resist antibiotics: Bacteria in biofilms are more resistant to antibiotics and host defenses

Mechanism of Slime Production in S. epidermidis

S. epidermidis produces slime through:

• Production of polysaccharide intercellular adhesin that strongly associates with the bacterial cell surface 1
• This adhesin mediates cell-to-cell adhesion and biofilm formation
• The extracellular polymeric matrix encases bacteria and forms the biofilm structure

Comparing the Organisms

Staphylococcus epidermidis (Option C)

• Produces slime as a major virulence factor
• Studies show 43.2% to 69.8% of clinical isolates are slime-producing 2, 3
• Slime production is associated with multidrug resistance and adherence to artificial surfaces 2
• The slime consists of a 20-kDa polysaccharide that serves as its major component 4

Staphylococcus aureus (Option B)

• Less commonly associated with slime production than S. epidermidis
• While some S. aureus strains can produce biofilms, they rely more on other virulence factors and toxins 1
• The AHA guidelines specifically note: "None of the major virulence factors or toxins of S. aureus have been found in CoNS [coagulase-negative staphylococci, including S. epidermidis]" 1

Candida albicans (Option A)

• Not characterized as a primary slime-producing organism in the provided evidence
• No mention of significant slime production in the guidelines

Klebsiella pneumoniae (Option D)

• Not identified as a significant slime producer in the provided evidence
• While it has a capsule, this is distinct from the slime production characteristic of S. epidermidis

Clinical Significance of Slime Production

The slime production by S. epidermidis has important clinical implications:

• Device-related infections: S. epidermidis biofilms are particularly problematic in cardiovascular implantable electronic device infections 1
• Antibiotic resistance: Slime-producing strains show significantly higher rates of multidrug resistance (47.4% vs 16% in non-slime producers) 2
• Diagnostic value: Antibodies to the 20-kDa polysaccharide in slime can be used to detect S. epidermidis infections and differentiate between slime-positive and slime-negative strains 4
• Ocular infections: In bacterial keratitis, slime production is significantly higher in isolates from patients (69.84%) compared to controls (22%) 3

Detection Methods

Slime production can be detected through:

• Congo red agar plate method 2
• Christensen's tube method 2
• Electron microscopy to visualize the slime layer anchoring to the bacterial cell wall 2
• ELISA using antibodies to the 20-kDa polysaccharide component 4

In conclusion, among the four organisms listed, Staphylococcus epidermidis (option C) is the organism most characterized by slime production, which contributes to its pathogenicity particularly in device-related infections.