CBIC CIC Exam With Confidence Using Practice Dumps

Theoptimal specimen for identifying the etiologic agentin a prosthetic joint infection (PJI) is ajoint aspirate(synovial fluid). This is because:

It provides direct access to the infected sitewithout contamination from external sources.

It allows for accurate microbiologic culture, Gram stain, and leukocyte count analysis.

Why the Other Options Are Incorrect?

A. Blood– Blood cultures may help detecthematogenous spreadbut are not the best sample for identifyinglocalizedprosthetic joint infections.

B. Wound drainage– Wound cultures oftencontain contaminantsfrom surrounding skin flora and do not accurately reflect joint space infection.

D. Sinus tract tissue– Cultures from sinus tracts often representcolonization rather than the primary infecting organism.

CBIC Infection Control Reference

APIC guidelines confirm thatjoint aspirate is the most reliable specimen for diagnosing prosthetic joint infections​.

In operating rooms,a minimum of 15 air changes per hour (ACH)is required, withat least 3 of those ACH being from fresh or outdoor air. This requirement helps reduce microbial contamination and provides a clean surgical environment.

According to theAPIC Text:

"In each, air should flow out of the room and the minimum ACH should be 15, withthree of these ACH being fresh or outdoor air."

This aligns with design specifications outlined in the 2006 Guidelines for design and construction of health care facilities.

The correct answer is C, "obtain surface cultures," as this is the best method to validate the suspicion of an environmental source for an outbreak of Serratia marcescens in the intensive care unit (ICU). According to the Certification Board of Infection Control and Epidemiology (CBIC) guidelines, Serratia marcescens is an opportunistic gram-negative bacterium commonly associated with healthcare-associated infections (HAIs), often linked to contaminated water, medical equipment, or environmental surfaces in ICUs. Obtaining surface cultures allows the infection preventionist (IP) to directly test environmental samples (e.g., from sinks, ventilators, or countertops) for the presence of Serratia marcescens, providing microbiological evidence to confirm or rule out an environmental source (CBIC Practice Analysis, 2022, Domain II: Surveillance and Epidemiologic Investigation, Competency 2.2 - Analyze surveillance data). This method is considered the gold standard for outbreak investigations when an environmental reservoir issuspected, as it offers specific pathogen identification and supports targeted interventions.

Option A (apply fluorescent gel) is a technique used to assess cleaning efficacy by highlighting areas missed during disinfection, but it does not directly identify the presence of Serratia marcescens or confirm an environmental source. Option B (use ATP system) measures adenosine triphosphate (ATP) to evaluate surface cleanliness and organic residue, which can indicate poor cleaning practices, but it is not specific to detecting Serratia marcescens and lacks the diagnostic precision of cultures. Option D (perform direct practice observation) is valuable for assessing staff adherence to infection control protocols, but it addresses human factors rather than directly validating an environmental source, making it less relevant as the initial step in this context.

The focus on obtaining surface cultures aligns with CBIC’s emphasis on using evidence-based methods to investigate and control HAIs, enabling the IP to collaborate with the committee to pinpoint the source and implement corrective measures (CBIC Practice Analysis, 2022, Domain II: Surveillance and Epidemiologic Investigation, Competency 2.3 - Identify risk factors for healthcare-associated infections). This approach is supported by CDC guidelines for outbreak investigations, which prioritize microbiological sampling to guide environmental control strategies (CDC Guidelines for Environmental Infection Control in Healthcare Facilities, 2019).