Optimizing the interpretation of Clostridioides difficile two-step diagnostic algorithm results through antimicrobial...

Area of Science:

• Infectious Diseases
• Clinical Microbiology
• Antimicrobial Stewardship

Background:

• Accurate differentiation between infection and colonization is crucial for appropriate antimicrobial therapy.
• Indeterminate diagnostic results, such as PCR+/Tox-, pose challenges in clinical decision-making.
• Antimicrobial stewardship programs play a key role in optimizing antibiotic use.

Purpose of the Study:

• To evaluate the clinical significance of indeterminate diagnostic results (PCR+/Tox-) in a real-world setting.
• To determine the proportion of indeterminate cases that represent true clinical infections.
• To inform clinical practice regarding the management of patients with indeterminate diagnostic findings.

Main Methods:

• A 4-year retrospective review of positive (PCR+/Tox+) and indeterminate (PCR+/Tox-) cases was conducted.
• The antimicrobial stewardship team collaborated with the most responsible physician for case classification.
• Patients were categorized as either infection or colonization based on clinical assessment.

Main Results:

• A total of 501 indeterminate samples (PCR+/Tox-) were analyzed.
• Out of 501 indeterminate samples, 213 (43%) were classified as clinical infections.
• This indicates a significant proportion of indeterminate results represent actual infections.

Conclusions:

• A substantial percentage of indeterminate diagnostic results are indicative of clinical infection.
• Ongoing clinical assessment and physician judgment are essential for managing patients with indeterminate results.
• These findings underscore the importance of careful evaluation to avoid under- or overtreatment.