1774. Impact of a Multiplex Polymerase Chain Reaction Assay on the Clinical Management of Adults Undergoing a Lumbar Puncture for Suspected Community-Onset Central Nervous System Infections

Patients admitted from the community with a suspected central nervous system (CNS) infection require prompt antimicrobial treatment and diagnostic evaluation. Our health network recently implemented a multiplex polymerase chain reaction (PCR) assay in-house.

This was a pre-/post-intervention study evaluating the impact that a multiplex PCR assay had on the clinical management of patients ≥18 years of age admitted from the community with a lumbar puncture (LP) performed for a suspected CNS infection. The primary outcome was Herpes Simplex Virus (HSV) PCR turnaround time (TAT). Secondary outcomes included inpatient length of stay (LOS), total antimicrobial days of therapy (DOT), and antiviral DOT. Patients were excluded if an LP was performed after hospital day 3, if they were on a systemic antimicrobial for a non-CNS indication, if they were a neurosurgical patient, and if they had a fungal CNS infection.

The pre- and post-intervention groups each had 57 patients. The average age was 51 and 52 years in the pre- and post-intervention groups, respectively. Four patients (7%) in the pre-intervention group were immunocompromised, compared with 9 (16%) in the post-intervention group. Four patients in the pre-intervention group had a positive PCR assay for either HSV or Varicella Zoster Virus (VZV), compared with 5 patients in the post-intervention group. Neither group had a positive cerebrospinal fluid culture, bacterial antigen assay, or bacterial PCR assay. The median (IQR) HSV PCR TAT was significantly longer in the pre-intervention group, 85 (78, 96) vs. 3.9 hours (2.9, 4.7), P < 0.001. The mean LOS was numerically greater in the pre-intervention arm (7 vs. 4.7 days, P = 0.069), as were the total antimicrobial DOT (9 vs. 7.4 days, P = 0.279) and antiviral DOT (3.9 vs. 2.7 days, P = 0.136). Pre-intervention antiviral DOT was significantly greater (3.1 vs. 1.6 days, P = 0.011) in patients without a positive HSV or VZV PCR.

Implementing a multiplex PCR assay for adults undergoing an LP for a suspected CNS infection significantly reduced the HSV PCR turnaround time. Antiviral DOT was significantly shorter in patients with a negative PCR result post-intervention. We also found a non-significant reduction in LOS, total antimicrobial DOT, and antiviral DOT.

All authors: No reported disclosures.