Evaluation of Clostridium difficile Infection with PET/CT Imaging in a Mouse Model

Area of Science:

• Medical Imaging
• Infectious Diseases
• Animal Models

Background:

• Current clinical and microbiological scores lack sensitivity for early identification of patients at risk for complicated Clostridium difficile infection (CDI).
• There is a need for more sensitive methods to predict CDI severity promptly.

Purpose of the Study:

• To evaluate 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography ([18F]FDG-PET) as a marker for severe CDI using a CDI animal model.
• To assess the correlation between [18F]FDG uptake and CDI severity.

Main Methods:

• Clostridium difficile infection (CDI) was induced in mice using cefoperazone and clindamycin, followed by inoculation with C. difficile strains (ribotype 001 and 027).
• Mice were divided into wild type, antibiotic control, and infected groups (h001 and h027).
• [18F]FDG-PET scans were performed, and animal weight, condition, and survival were monitored daily for 9 days.

Main Results:

• The h027 ribotype group, associated with high toxin production, exhibited significantly higher colon [18F]FDG uptake (0.93 ± 0.38) compared to controls and the h001 group (0.52 ± 0.20).
• The h027 group experienced higher mortality (66.7%) and prolonged symptoms.
• Clinical scores correlated significantly with colon and cecum [18F]FDG uptake (rho = 0.78, p < 0.0001).

Conclusions:

• Higher colon and cecum [18F]FDG uptake in a CDI animal model is associated with infection severity, particularly with high toxin-producing strains like ribotype 027.
• Colon [18F]FDG uptake shows potential as an early predictor for the severity of Clostridium difficile infection.