Comparison of Multiplex Gastrointestinal Pathogen Panel and Conventional Stool Testing for Evaluation of Diarrhea in Patients with Inflammatory Bowel Diseases

Background and Aims Gastrointestinal pathogen panels (GPPs) are increasingly being used for evaluation of diarrhea. The impact of these tests on patients with inflammatory bowel diseases (IBD) is unknown. We performed a time-interrupted cohort study comparing GPPs and conventional stool evaluation in patients with IBD with diarrhea. Methods We included 268 consecutive patients with IBD who underwent GPP (BioFire Diagnostics ® ) ( n = 134) or conventional stool culture and Clostridium difficile polymerase chain reaction testing ( n = 134) during suspected IBD flare between 2012 and 2016. Primary outcome was composite of 30-day IBD-related hospitalization, surgery, or emergency department visit; secondary outcome was IBD treatment modification. Results Overall, 41/134 (30.6%) patients tested positive on GPP (18 C. difficile, 17 other bacterial infections, and 6 viral pathogens) versus 14/134 patients (10.4%, all C. difficile) testing positive on conventional testing. Rate of IBD treatment modification in response to stool testing was lower in GPP group as compared conventional stool testing group (35.1 vs. 64.2%, p