Tests for HSV Encephalitis Diagnosis of HSV encephalitis may require a number of tests. New imaging techniques can detect swelling in affected lobes in the brain, although such abnormalities may not be detectable until late in the course of the disease. Brain biopsy is the most reliable method of diagnosing HSV encephalitis, but it is also the most invasive and is generally performed only if the diagnosis is uncertain. PCR uses a piece of the DNA of the virus and then replicates millions of times until the virus is detectable. This test can identify specific strains of the virus and asymptomatic shedding.
Sensitivity is almost equal to viral culture and results are also much quicker.
In the asymptomatic newborn delivered from an infected mother, cultures should be taken between 24 and 48 hours after birth. A culture taken right at the time of delivery may give a false indication of infection in the baby, simply because it can carry some of the mother's virus from the birth canal. All rights reserved.