Microbiology, Pathology and Nutrition
Microbiology, pathology and nutrition cover infection, immunity, tissue injury and dietary requirements. Items test sterilisation, immunity types, inflammation and nutritional assessment.
Core rules
- Sterilisation kills all microorganisms including spores (autoclave 121 °C, 15 psi, 15 minutes); disinfection reduces pathogens on inanimate objects but may not kill spores.
- Innate immunity is non-specific; adaptive immunity is specific and has memory. Active immunity develops after infection or vaccination; passive immunity is transferred (maternal antibodies, immunoglobulin).
- Acute inflammation: redness, heat, swelling, pain and loss of function, mediated by histamine and prostaglandins.
- Nutrition: BMI = weight (kg) ÷ height (m)². Marasmus causes severe wasting; kwashiorkor causes oedema and low albumin.
Worked example
A wound swab grows Staphylococcus aureus. The nurse uses contact precautions, ensures hand hygiene and administers the prescribed antibiotic after culture. Reasoning: culture confirms the organism and guides therapy; precautions limit cross-infection.
Traps
Calling handwashing sterilisation; confusing active with passive immunity; using BMI for a fluid-overloaded patient without interpretation; forgetting that boiling does not reliably kill spores.