Clostridium difficile is a major cause of health care-associated infection. Molecular tests are increasingly used to diagnose C difficile infection (CDI), but many molecular test-positive patients lack toxins that historically defined disease, making it unclear if they need treatment. Recent increases of CDI nationwide have been linked to greater C. difficile detection after the introduction of molecular tests (PCR), which are more sensitive and detect microbial DNA instead of toxin. However, toxin production typically correlated better with clinical disease. PCR detects toxin genes regardless of toxin production, therefore, PCR results only truly do not reflect clinical disease. Concern that simply colonized patients with another cause of symptoms are overdiagnosed and mistreated initiated a prospective cohort study at UC Davis. Over 1400 hospitalized patients were tested for the purposes of the study. Study found that 55.3% of patients with a positive C .difficile PCR test result lacked toxin. Therefore, the results of the study suggest that molecular tests are not specific for CDI, even in the presence of symptoms, and most patients with negative toxin test results and C difficile detected by PCR do not need treatment for CDI. No C. difficile related complications were noted in patients with a negative toxin test.
Overdiagnosis of Clostridium difficile Infection in the Molecular Test Era
Christopher R. Polage, MD, MAS1,2; Clare E. Gyorke, BS1; Michael A. Kennedy, BS1; et al
Overdiagnosis of Clostridium difficile Infection in the Molecular Test Era
Christopher R. Polage, MD, MAS1,2; Clare E. Gyorke, BS1; Michael A. Kennedy, BS1; et al
