Lecture 13: Sepsis Flashcards
What is sepsis?
A life-threatening immune overreaction to bloodstream infection (septicaemia), leading to tissue damage and organ failure.
What is the difference between bacteraemia and septicaemia?
Bacteraemia = bacteria in blood; septicaemia = systemic inflammatory response to bacteraemia.
What does the “SEPSIS” mnemonic stand for?
Slurred speech
Extreme shivering/fever
Passing no urine
Severe breathlessness
It feels like dying
Skin mottling
Name 3 additional symptoms in children.
Weak/high-pitched crying, blotchy skin, lethargy.
What is the global annual mortality rate for sepsis?
~11 million deaths (49 million cases).
Which group has higher sepsis mortality in the UK?
Elderly, immunocompromised, and neonates.
Name 5 common pathogens causing sepsis.
S. aureus, E. coli, S. pneumoniae, Enterococcus spp., Candida albicans
Why is S. aureus bacteraemia clinically significant?
Indicates a source infection (e.g., abscess, pneumonia) requiring further investigation.
What is the gold standard for sepsis diagnosis?
Blood cultures (paired bottles: aerobic + anaerobic).
What is the purpose of the BacTec system?
Detects bacterial growth via fluorescence; alerts lab when positive.
Why must blood cultures be drawn before antibiotics?
Antibiotics can suppress bacterial growth, yielding false negatives.
What does growth on MacConkey agar suggest?
Gram-negative enterobacteria (e.g., E. coli = pink lactose fermenters; Salmonella = colorless).
How is S. pneumoniae identified in blood cultures?
Optochin disc test (+ve) + alpha-hemolysis on blood agar.
What indicates Candida sepsis?
Yeast colonies on blood agar + confirmed with Sabouraud agar.
Why is polymicrobial bacteraemia dangerous?
Higher mortality; requires aggressive, broad-spectrum therapy.
What is the first-line action for suspected sepsis?
Immediate broad-spectrum antibiotics (e.g., piperacillin-tazobactam) + fluid resuscitation.
What is a key risk factor for Candida sepsis?
Immunocompromise, central venous catheters, or prolonged antibiotics.
Why is Neisseria meningitidis critical to identify rapidly?
Can progress to meningitis; requires urgent IV antibiotics (e.g., ceftriaxone).
