Utilization of herpes simplex PCR assays for cerebrospinal fluid in a pediatric health care setting

An assessment was made of the utilization and impact of a diagnostic polyme rase chain reaction (PCR) assay for the diagnosis of herpes simplex viruses (HSV) 1 and 2 in cerebrospinal fluid of children who attended a Canadian p ediatric referral centre. One hundred and three assays were performed on sp ecimens from 103 patients during the period August 1997 to September 1998. Patient ages ranged from newborn to 16 years. Indications for HSV PCR inclu ded seizures with or without fever (56.3%), aseptic meningitis (16.5%), and encephalopathy with or without fever (10.7%). Only 2 of 103 (1.9%) assays were positive, including one each for HSV1 and HSV2. Control specimens that were seeded with virus indicated inhibition for 24.3, 8.8, and 6.8% of ass ays for HSV1, HSV2, and both HSV1 and HSV2, respectively. The mean turn-aro und time for HSV PCR was 2.5 days, and 90.3% were completed in less than 5 days. Acyclovir was administered to 78.6% of the patients overall; the resu lts of the HSV PCR impacted on the treatment courses for 36 individuals. Ne vertheless, 16.5% of patients continued to receive extended courses of anti viral therapy despite negative HSV PCR assays. Although it is desirable to decrease the frequency of PCR inhibitions and to further decrease the inter val to assay completion, HSV PCR does have a significant impact on antivira l use in this setting.