A randomized control trial of a multiplex gastrointestinal PCR panel versus usual testing to assess antibiotics use for patients with infectious diarrhea in the emergency department

Document Type

Journal Article

Publication Date



Journal of the American College of Emergency Physicians open








Antibiotic Stewardship; PCR testing; Point‐of care testing; diagnostic testing; emergency medicine; infectious diarrhea


Objective: This study analyzed physician treating behavior through the use of a multiplex gastrointestinal polymerase chain reaction (GI PCR) test compared with usual testing in emergency department (ED) patients with suspected acute infectious diarrhea to assess differences in antibiotic management. Methods: A prospective, single-center, randomized control trial was designed to investigate antibiotic use in ED patients with moderate to severe suspected infectious diarrhea, comparing those who received GI PCR to those who received usual testing. ED patients with signs of dehydration, inflammation, or persistent symptoms were randomized to either the experimental arm (GI PCR) or the control arm (usual testing or no testing). Results: A total of 74 patients met study criteria and were randomized to either the experimental GI PCR arm (n = 38) or to the control arm (n = 36). Participants in the GI PCR arm received antibiotics in 87% of bacterial or protozoal diarrheal infections (13/15) whereas those in the control arm received antibiotics in 46% of bacterial or protozoal infections (6/13) ( value 0.042) with 2-proportion difference 0.41 (95% confidence interval 0.07 and 0.68). Conclusions: ED use of multiplex GI PCR led to an increase in antibiotic use for bacterial and protozoal causes of infectious diarrhea compared to usual testing. This increase in antibiotics appears to be appropriate given patients' moderate to severe symptoms and a definitive identification of a likely bacterial or protozoal cause of symptoms. Results should be interpreted with caution because of the small sample size.


Emergency Medicine