Effect of Rapid Molecular Diagnostic Testing and Antimicrobial Stewardship on Antimicrobial Therapy of Respiratory Infections

Abstract

BackgroundRapid molecular methods have created new opportunities for the clinical microbiology laboratory to affect patient care in the areas of initial diagnosis and therapy. Rapid diagnostic tests provide collaborative opportunities for antimicrobial stewardship Teams (AST) to improve patient outcomes and decrease antimicrobial use. In January of 2017 our institution initiated use of a FDA approved multiplex polymerase chain reaction (PCR) Respiratory Panel. The objective of this evaluation was to assess the clinical impact along with procalcitonin (PCT) on quality of patient care when used in conjunction with antimicrobial stewardship.MethodsMolecular testing was performed using the BioFire FilmArray® Respiratory Panel [RP] (BioMerieux). The medical staff was encouraged to order an Influenza/RSV PCR test prior to ordering the full RP. The results of RP and PCT were available the same day as ordered. AST recommended the RP as part of its intervention on several patients and provided advice based on results.ResultsFrom January-April the results of 81 tests for the respiratory panel were evaluated. Of these 30 were positive (+) for virus (most common-Human Metapneumovirus [HMV]-13, Coronavirus-7). PCT (ng/mL) results were available on 69. Most common final diagnosis: Pneumonia-31; AECOPD-16. Effect on duration of antimicrobial therapy (ABX) and hospital length of stay (LOS):RP result for virusMean Duration ABX after test resultLength of Hospital Stay (LOS) after test resultVirus + (n = 30)1.6 days3.6 daysVirus – (n = 51)4 days4.9 daysVirus +; PCT < 0.25 (n = 17)1.2 days2.9 daysVirus+; PCT < 0.25; AST* (n = 10)0.6 days2.7 days*AST recommendation. There was no difference in 30-day readmission rates.Of the patients with pneumonia; 11 had + RP for virus (7-HMV), 4 had co-infection with + bacteria with mean PCT of 0.62 and mean duration of ABX 6 days after test result; of the 7 with no bacterial co-infection the mean PCT was 0.12 with mean duration of ABX 0.28 days after the test resultConclusionThe results of the RP led to a decrease in ABX duration, which was most profound in the patients for whom AST intervened. LOS was also reduced. Utilization of RP and PCT facilitated better ABX use.Disclosures T. M. File Jr., BioMerieux: Scientific Advisor, Consulting fee