Staphylococcus aureus and MRSA Overview

Staphylococcus aureus

Gram-positive bacterium causing various infections.

MRSA

Methicillin-resistant Staphylococcus aureus strain.

Virulence factors

Components enabling bacteria to cause disease.

Scalded skin syndrome

Condition causing skin peeling in children.

Endocarditis

Infection of heart valves by bacteria.

Catalase

Enzyme that breaks down hydrogen peroxide.

Peptidoglycan

Cell wall component providing structural integrity.

Lipoteichoic acids

Cell wall components contributing to virulence.

Staphyloxanthin

Carotenoid pigment aiding in bacterial survival.

Coagulases

Enzymes forming staphylothrombin complex for protection.

Protein A

Binds host antibodies, evading immune response.

Alpha-toxin

Pore-forming toxin with dermonecrotic effects.

Beta-toxin

Sphingomyelinase C hydrolyzing cell membrane components.

Gamma-toxin

Cytolytic toxin affecting erythrocytes and leukocytes.

Superantigens

Toxins causing excessive T-cell activation.

Toxic shock syndrome toxin (TSST-1)

Superantigen linked to severe systemic reactions.

Mannitol-salt agar (MSA)

Selective medium for isolating S. aureus.

Catalase test

Test detecting oxygen release from S. aureus.

Coagulase test

Test showing agglutination with rabbit serum.

Methicillin resistance

Resistance mediated by penicillin binding protein 2a.

HA-MRSA

Hospital-acquired methicillin-resistant Staphylococcus aureus.

CA-MRSA

Community-acquired methicillin-resistant Staphylococcus aureus.

Panton-Valentine leucocidin (PVL)

Exotoxin linked to severe CA-MRSA symptoms.

Prophylaxis

Preventive measures against MRSA infections.

Lugdunin

Cyclic peptide inhibiting S. aureus nasal colonization.

Sepsis

Immune response to blood infection causing organ failure.

Septicaemia

Bloodstream infection caused by various pathogens.

Fibrin coating

Protects bacteria from immune system detection.

Nikolsky test

Skin test indicating epidermal detachment.

Antimicrobial resistance mechanisms

Strategies bacteria use to evade drug effects.