Introduction

Question 1

What does MCNS stand for?

Answer 1

• Microscopy (Gram stain) - Identify gram+/gram-
• Culture - Identify causative bug
• Sensitivity - Identify best antibiotics to use

Question 2

What colour is gram+

Answer 2

• Purple
• Due to thick peptidoglycan

Question 3

What colour is gram-

Answer 3

• Pink
• Due to thin peptidoglycan

Question 4

Can virus be viewed under microscope? + can it be cultured on an agar plate?

Answer 4

• Cannot be visualized under a labs conventional microscope
• Virus cannot be cultured on agar plate, use PCR instead

Question 5

What is commensal bacteria?

Answer 5

• Also called normal flora
• Bacteria that are normally found on the human body
• Not harmful
• May contribute beneficial affects

Question 6

What is bacteria colonization?

Answer 6

• Presence of bacteria without infection
• Usually in moist warm body areas
• Increases in
  
  • Hospitalized patients
  • Patients with medical conditions
  • Patients given antibiotics

Question 7

What is bacteria infection?

Answer 7

• Invasion by and multiplication of pathogens in bodily parts or tissue
• Produces subsequent tissue injury or disease

Question 8

Things to take note about interpretation of lab results for bacterial or fungal culture if its positive? + In contrast with PCR/POCT? (2)

Answer 8

• Bacterial or fungal culture report should be interpreted in conjunction with clinical presentation (Just because positive does not = its clinically significant)
• PCR/POCT positive results usually confirms infection

Question 9

Things to take note about interpretation of lab results for bacterial or fungal if its negative? (5)

Answer 9

• If negative does not exclude infection, it might mean:
  
  • Test not sensitive enough (Patient pretreated with antibiotics)
  • Test performed too soon/too late after infection
  • Poor sampling technique
  • Incorrect test for the infection
  • Patient has been treated with antibiotics