Healthcare Infections

Question 0

Understand the range of hospital acquired infections

Answer 0

Virus - norovirus, influenza
Bacteria - staph aureus (MRSA), clostridium difficile, E. coli, TB
Fungi - candida albicans, aspergillus
Parasite - malaria

Question 1

Expand the description of pathogen/person/practise/place as it applies to hospital acquired infections

Answer 1

Pathogen - virulence, ecological interactions (resistance)
Person - risk factors (general e.g. antimicrobial prophylaxis and specific e.g. MRSA screens), interactions (other patients, healthcare workers, visitors)
Practise - activities of healthcare workers, policies and implementation, organisational structure
Place - healthcare environment (fixed features e.g. layout, beds, toilets, variable features e.g. carpeting, washbasins, cleaning, medical devices, good food hygiene, positive/negative pressure rooms

Question 2

Describe principles relating to infection control in a hospital setting

Answer 2

Bare below elbows, hand washing
Isolation of infected patients (negative pressure room), protection of susceptible patients (positive pressure room)
Antimicrobial prescribing
Cleaning - disinfectant, steam cleaning, hydrogen peroxide vapour
Medical devices - single use equipment, sterilisation

Question 3

Describe the use of Personal Protective Equipment with regard to infections in a hospital setting

Answer 3

Disposable face masks, aprons and gloves

Wash hands before and after interacting with patient

Question 4

Describe the characteristics of Clostridium difficile, its pathogenesis, and management

Answer 4

Gram +ve bacilli, spore forming (spread easily)
Associated with recent antibiotic use e.g. of amoxicillin
Produces toxins - Toxin A (enterotoxin), Toxin B (cytotoxin) which cause inflammation and damage of lower gut
Diarrhoea and vomiting therefore require IV fluid
Treat with metronidazole if no severe markers, vancomycin if severe markers

Question 5

Describe the characteristics of Staphylococcus aureus with regard to hospital acquired infections and drug resistance

Answer 5

Gram +ve cocci in clusters
Produces B-lactamases, coagulase, DNAse, exotoxins 
Bind to and inactivate antibodies 
Treat with flucloxacillin 
Treat MRSA with vancomycin

Question 6

Describe the characteristics of Norovirus and application of infection prevention principles

Answer 6

Non enveloped, ss RNA
Highly contagious (spread by foecal/oral route)
Replicates in small intestine causing vomiting and diarrhoea so IV fluids necessary
Condition is self limiting however risk of mortality in extremes of age, immunocompromised patients