2001. Clinical management changes after positive multiplex gastrointestinal pathogen panel testing for evaluation of diarrhea


 
 
 IDSA guidelines for diarrhea include pathogen-specific management. Compared to non-molecular tests, multiplex gastrointestinal pathogen panels (GIPPs) may allow for more timely and cost-effective diagnoses and care. However, this has yet to be definitively demonstrated. Our objective was to determine the impact of positive GIPP results on clinical management, including antimicrobial use.
 
 
 
 We performed a retrospective study of patients with diarrhea and a positive GIPP result (xTAG Gastrointestinal Pathogen Panel, Luminex) at an academic, tertiary-care medical center from January-December 2018. We excluded immunocompromised patients (solid organ or stem cell transplant, HIV with absolute CD4 count < 200 cells/µL, primary immunodeficiency, and immunosuppressive medications including biologics). We collected patient and clinical data via electronic medical record review. Our primary outcome of interest was change in antimicrobial usage.
 
 
 
 A total of 2,333 GIPP tests were performed of which 266 (11.4%) were positive. Of 193 patients who met inclusion criteria, 34% were tested in an emergency room, 38% in outpatient clinics, and 29% on inpatient wards. Of these, 55% were men, 65% were white, and the median age was 31 years (interquartile range, IQR 5-56). The median turnaround time from GIPP collection to result was 31 hours (IQR 24-53). The most frequently identified pathogens were norovirus, Salmonella, and Campylobacter (Figure 1). In 43% of patients, results led to one or more management changes including antibiotic discontinuation (8%) and antibiotic initiation (25%). Antibiotics were most often discontinued for norovirus (Figure 1A) and started for Campylobacter (Figure 1B). Other management changes occurred in 13% of patients, including avoidance of further diagnostic testing and isolation precaution change. The median turnaround time did not differ for GIPPs that were (30 hours; IQR 22-50) or were not (32 hours; IQR 25-56) associated with management change.
 
 
 
 Positive GIPP results can prompt changes in antimicrobial treatment in non-immunocompromised patients with diarrhea. Future efforts will evaluate the appropriateness of these management changes.
 
 
 
 Melissa B. Miller, PhD, Abbott Molecular: Grant/Research Support|Agena Biosciences: Board Member|ArcBio: Grant/Research Support|Cepheid: Board Member|Luminex Molecular Diagnostics: Board Member|QIAGEN: Board Member|QIAGEN: Grant/Research Support|Sherlock Biosciences: Advisor/Consultant|Talis Biomedical: Board Member|Thermo Fisher: Honoraria|Werfen: Board Member.
