Repeat stool testing for Clostridium difficile using enzyme immunoassay in patients with inflammatory bowel disease increases diagnostic yield

AbstractBackground:The incidence and severity of Clostridium difficile infection (CDI) in patients with inflammatory bowel disease (IBD) is increasing. CDI is diagnosed by toxin enzyme immunoassay (EIA) or real-time polymerase chain reaction (PCR) performed on stool samples. An earlier study evaluating EIA in IBD patients with CDI suggested that more than one stool sample be tested to increase diagnostic yield. We investigated whether repeat stool testing improves diagnostic accuracy for CDI in hospitalized IBD patients compared to hospitalized patients with CDI and no IBD.Methods:We performed retrospective data analysis from January 2005–May 2011 on 63,086 hospitalized patients who were tested for CDI using EIA or PCR. Of these, 2579 patients had IBD. Transition probabilities were calculated based on results from repeated tests.Results:Inclusive of all inpatients tested for CDI, 56,583 were tested using toxin EIA and 6503 were tested using PCR. In patients with no IBD, the first stool sample tested was p...