BCM Diagnostic Virology Laboratory August 1997 - Vol. 2, No. 8 Picornaviruses, especially enteroviruses, were the most commonly isolated viruses in July. Seven were grown from respiratory samples, seven were grown from stool samples, and four were grown from CSF samples. Enteroviral meningitis has occurred this summer, and typing of enteroviruses isolated from nine CSF samples so far show five Echovirus type 6, one Echovirus type 7, one Echovirus type 30, and two Coxsackie virus type A9. Adenovirus also remained strong this summer. We also continue to isolate RSV and parainfluenza, types 1 and 3 at low levels.
Enteroviruses are, of course, the most common cause of viral meningitis in the summer in Houston.
The best test to diagnose viral meningitis is a viral culture of the CSF, since isolation of the virus from this site provides a definitive diagnosis. Isolation of enterovirus from the throat or stool provides supportive evidence that your patient's viral meningitis is due to enterovirus. Serology is rarely useful to the clinician to diagnose routine viral meningitis and should be reserved for special circumstances. Obtain CSF early during the first few days of illness. The longer into the illness, the more opportunity the host defenses will have to neutralize the virus.