Impact of a Rapid Herpes Simplex Virus PCR Assay on Duration of Acyclovir Therapy

Abstract

Herpes simplex virus (HSV) infections of the central nervous system (CNS) are associated with significant morbidity and mortality rates in children. This study assessed the impact of a direct HSV (dHSV) PCR assay on the time to result reporting and the duration of acyclovir therapy for children with signs and symptoms of meningitis and encephalitis. A total of 363 patients with HSV PCR results from cerebrospinal fluid (CSF) samples were included in this retrospective analysis, divided into preimplementation and postimplementation groups. For the preimplementation group, CSF testing was performed using a laboratory-developed real-time PCR assay; for the postimplementation group, CSF samples were tested using a direct sample-to-answer assay. All CSF samples were negative for HSV. Over 60% of patients from both groups were prescribed acyclovir. The average HSV PCR test turnaround time for the postimplementation group was reduced by 14.5 h (23.6 h versus 9.1 h; P < 0.001). Furthermore, 79 patients (43.6%) in the postimplementation group had dHSV PCR results reported <4 h after specimen collection. The mean time from specimen collection to acyclovir discontinuation was 17.1 h shorter in the postimplementation group (31.1 h versus 14 h; P < 0.001). The median duration of acyclovir therapy was also significantly reduced in the postimplementation group (29.2 h versus 14.3 h; P = 0.01). Our investigation suggests that implementation of rapid HSV PCR testing can decrease turnaround times and the duration of unnecessary acyclovir therapy.

Keywords: HSV; acyclovir; encephalitis; herpes simplex virus; meningitis; rapid diagnosis; toxicity.

FIG 1

Creatinine levels of four patients with elevated creatinine levels after acyclovir initiation. The timeline shows the approximate time after the initiation of intravenous acyclovir treatment. Patients 1 and 2 were from the preimplementation group, and patients 3 and 4 were from the postimplementation group. The downward arrow on each line indicates when the HSV PCR results were reported. The large plus sign on each line indicates when acyclovir therapy was discontinued. The solid lines indicate patients from the preimplementation group, and the dashed lines indicate patients from the postimplementation group.