Paper I
Question
List toxin mediated infections of staphylococcus aureus
Answer
Toxin-mediated infections/diseases caused by Staphylococcus aureus (illness driven primarily by a specific exotoxin, rather than requiring extensive tissue invasion by the organism itself):
- Staphylococcal food poisoning — ingestion of pre-formed, heat-stable staphylococcal enterotoxin in improperly stored food, causing rapid-onset (2–6 hours) nausea, vomiting, and abdominal cramps.
- Toxic shock syndrome (TSS) — caused by TSST-1, a superantigen exotoxin, producing fever, hypotension/shock, diffuse rash with desquamation, and multiorgan dysfunction.
- Scalded skin syndrome (Staphylococcal Scalded Skin Syndrome, SSSS/Ritter’s disease) — caused by exfoliative (epidermolytic) toxins A and B, which cleave desmoglein-1 in the epidermis, causing widespread skin blistering and exfoliation, predominantly in neonates/young children.
- Bullous impetigo — a localized form of exfoliative-toxin-mediated skin disease, causing superficial blistering skin lesions.
(Superantigen-mediated toxic shock and enterotoxin-mediated food poisoning both act via the toxin alone, without necessarily requiring ongoing bacterial invasion at the site of illness — a defining feature of toxin-mediated staphylococcal disease.)