Association of Herpes Simplex Virus Testing with Hospital Length of Stay for Infants ≤60 Days of Age Undergoing Evaluation for Meningitis
Although neonatal herpes simplex virus (HSV) causes significant morbidity, utilization of the cerebrospinal fluid (CSF) HSV polymerase chain reaction (PCR) test remains variable. Our objective was to examine the association of CSF HSV PCR testing with length of stay (LOS) in a 20-center retrospective cohort of hospitalized infants aged ≤60 days undergoing evaluation for meningitis after adjustment for patient-level factors and clustering by center. Of 20,496 eligible infants, 7,399 (36.1%) had a CSF HSV PCR test performed, and 46 (0.6% of those tested) had a positive test. Infants who had a CSF HSV PCR test performed had a 23% longer hospital LOS (incident rate ratio 1.23; 95% CI: 1.14-1.33). Targeted CSF HSV PCR testing may mitigate the impact on LOS for low-risk infants.
© 2019 Society of Hospital Medicine
Neonatal herpes simplex virus (HSV) is associated with significant morbidity and mortality,1 particularly when the diagnosis or treatment is delayed.2 Therefore, many infants aged ≤60 days being evaluated for meningitis undergo cerebrospinal fluid (CSF) HSV polymerase chain reaction (PCR) testing even though the risk of HSV infection is low [estimated at 0.4% of those undergoing evaluation for central nervous system (CNS) infection].3 A single-center study demonstrated that CSF HSV PCR testing increases the hospital length of stay (LOS) for infants aged ≤56 days,4 although these single-center findings may not be generalizable. To this end, we measured the association between CSF HSV PCR testing and LOS in a multicenter cohort of hospitalized young infants.
METHODS
Study Design
We conducted a planned secondary analysis of a retrospective cohort of infants aged ≤60 days who presented to the emergency department (ED) between January 1, 2005 and December 31, 2013, enrolled in the Pediatric Emergency Medicine Collaborative Research Committee (PEM CRC) HSV study.3 Our study was limited to the 20 hospitals that contributed hospital LOS data. The study protocol was approved by each site’s institutional review board with permission for data sharing.
Study Population
Eligible infants were identified at each site using a site-specific electronic search strategy. Infants were eligible for inclusion if a CSF culture was obtained in the ED or within 24 hours of ED arrival. We excluded infants who were discharged from the ED and those with missing hospital LOS data.
