CER Microbiology and Infection Control 4

Question 1

Which of the following microorganisms is used as the biological indicator (BI) for validating ETO (ethylene oxide) sterilization?

Accepted Answer

Bacillus atrophaeus (subtilis)

Answer

Bacillus atrophaeus (formerly B. subtilis) spores are the standard biological indicator for ETO sterilization validation due to their high resistance to this agent.

Question 2

What is the primary purpose of using enzymatic detergents in the manual cleaning of endoscopes?

Accepted Answer

To break down proteins, fats, and carbohydrates in organic soil

Answer

Enzymatic detergents contain enzymes (proteases, lipases, amylases) that chemically break down organic soil — proteins, fats, and carbohydrates — facilitating their physical removal.

Question 3

In chain-of-infection terminology, 'mode of transmission' for an endoscopy-associated infection most commonly refers to:

Accepted Answer

Direct contact via the contaminated endoscope (contact transmission)

Answer

Endoscopy-associated infections are primarily transmitted via direct contact when a contaminated scope comes into contact with mucosal surfaces of a new patient.

Question 4

Which organism has caused the most widely publicized endoscopy-related outbreaks in recent years, largely due to the difficulty of cleaning duodenoscopes?

Accepted Answer

Carbapenem-resistant Enterobacteriaceae (CRE)

Answer

CRE, particularly carbapenem-resistant Klebsiella pneumoniae, has caused major outbreak clusters linked to duodenoscopes because their elevator mechanism is difficult to adequately clean.

Question 5

The Spaulding classification system categorizes medical devices based on:

Accepted Answer

The risk of infection based on the intended use and body site

Answer

The Spaulding classification (critical, semi-critical, non-critical) categorizes devices by the level of infection risk associated with how and where they contact the patient.

CER - Certified Endoscope Reprocessor Practice Test

CER - Certified Endoscope Reprocessor Practice Test

CER Microbiology and Infection Control 4