Multicenter Prevalence Study Comparing Molecular and Toxin Assays for Clostridioides difficile Surveillance,...

Area of Science:

• Infectious Diseases
• Clinical Microbiology
• Public Health Surveillance

Background:

• International public health bodies recommend surveillance for Clostridioides difficile infections in hospitalized patients.
• Discrepancies in diagnostic algorithms hinder accurate cross-institutional and international comparisons of infection rates.

Purpose of the Study:

• To compare Clostridioides difficile surveillance using two distinct diagnostic methods: Polymerase Chain Reaction (PCR) and Enzyme Immunoassay (EIA).
• To evaluate the impact of different diagnostic algorithms on reported infection prevalence in a nationwide study.

Main Methods:

• A nationwide study in Switzerland involving 76 hospitals over two sampling days (winter and summer 2015).
• Analysis of routinely collected stool samples from hospitalized patients presenting with diarrhea.
• Comparison of detection rates using EIA and PCR methods.

Main Results:

• Enzyme immunoassay (EIA) detected Clostridioides difficile at rates of 6.4 cases/10,000 patient bed-days (winter) and 5.7 cases/10,000 patient bed-days (summer).
• Polymerase chain reaction (PCR) detected the pathogen at higher rates: 11.4 cases/10,000 patient bed-days (winter) and 7.1 cases/10,000 patient bed-days (summer).
• Utilizing PCR alone resulted in an <80% increase in reported C. difficile prevalence compared to a two-stage EIA-based algorithm.

Conclusions:

• The choice of diagnostic method significantly influences the reported prevalence of Clostridioides difficile infections.
• PCR-based surveillance alone may overestimate infection rates compared to EIA-based methods, impacting public health comparisons.
• Standardization of diagnostic algorithms is crucial for reliable surveillance and comparison of C. difficile infection data.