1996. Association between Multiplex Polymerase Chain Reaction Stool Diagnostic Testing and Pathogen Detection, Healthcare Resource Use, and Cost Among Adult Outpatients Treated in United States Hospitals for Acute Infectious Gastroenteritis
Authors: Moon Rena , Bleak Tammy C , Rosenthal Ning , Couturier Brianne , Hemmert Rachael , Timbrook Tristan T , Brown Harold , Fang Ferric C 
Published: December 2022

Abstract

Background
Multiplex polymerase chain reaction (PCR) gastroenteritis testing panels simultaneously detect multiple pathogens with rapid turnaround, allowing more accurate and timely diagnosis and treatment. This retrospective observational study assessed the association between stool test type (i.e., multiplex PCR panel with &lt; 12 target pathogens [PCR&lt; 12], multiplex PCR panel with ≥ 12 target pathogens [PCR12], traditional work-up [TW]) and healthcare resource use (HRU), cost, and diagnostic yield in adult outpatients treated in U.S. hospitals for acute infectious gastroenteritis (AIG).

Methods
Using large geographically diverse PINC AI Healthcare Database data from January 1, 2016–June 30, 2021, we analyzed adults (≥ 18-years) with an AIG diagnosis and stool test performed during an outpatient visit. Pathogen analysis was performed in those with microbiology data available.

Results
Among 36,787 patients, TW was most often performed (57.0%), followed by PCR12 (30.2%) and PCR&lt; 12 (12.8%). Patients with PCR12 were more likely younger, Hispanic/Latino, and uninsured, and less likely socially vulnerable compared to TW (all p&lt; 0.01, Table 1). PCR12 was more common in patients from large (500+ beds), teaching, urban hospitals in the Midwest, compared to patients with TW (all p&lt; 0.01, Table 2). Patients with PCR12 were more likely to have a history of transplantation or HIV/AIDS (both p&lt; 0.01). PCR12 was associated with a higher mean index visit cost (by $101) but lower mean 30-day follow-up cost (by $130) than TW (Table 3). Patients with PCR12 had lower 30-day AIG-related admission risk than TW (1.7% vs. 2.7% p&lt; 0.01). Among 8,451 patients with microbiology data, PCR12 was associated with fewer stool tests per patient (mean:1.61 vs. 1.26), faster turnaround time (mean: 6.3 vs. 25.7 hours) and less likelihood of receiving in-hospital antibiotics (39.4% vs. 47.1%, all p&lt; 0.01) than TW. A higher percentage of patients with PCR12 had a target pathogen detected (73.1%) compared to PCR&lt; 12 (63.6%) or TW (45.4%, p&lt; 0.01). Table 1.Patient characteristics of hospital-based infectious gastroenteritis outpatients during January 1, 2016 - June 30, 2021, stratified by type of stool testTable 2.Clinical and hospital characteristics of hospital-based infectious gastroenteritis outpatients during January 1, 2016 - June 30, 2021, stratified by type of stool testTable 3.Outcomes of hospital-based infectious gastroenteritis outpatients during January 1, 2016 - June 30, 2021, stratified by the type of stool test

Conclusion
PCR12 multiplex panels were associated with lower 30-day follow-up cost and risk of IG-related hospitalization. PCR12 was also associated with less secondary testing, reduced in-hospital antibiotic use, faster turnaround, and increased diagnostic yield compared to TW.

Disclosures
Rena Moon, MD, MPH, Premier Inc: Employee Tammy C. Bleak, PharmD, MSc, bioMerieux: Employee of bioMerieux Ning Rosenthal, MD, PhD, MPH, Premier Inc: Employee|Premier Inc: Stocks/Bonds Brianne Couturier, PhD, bioMerieux: Employee of bioMerieux Rachael Hemmert, MSPH, bioMerieux: Employee of bioMerieux Tristan T. Timbrook, PharmD, bioMerieux: Employee of bioMerieux Harold Brown, MBA, MHA, Premier Inc: Employee Ferric C. Fang, MD, bioMerieux: Advisor/Consultant.