1.) Are there any elements on H&P that make you suspect viral meningitis in adult patients? Do you LP all patients you suspect have viral meningitis?
2.) Does a “normal” CSF reassure you that the patient does not have bacterial meningitis?
3.) Do you use CSF lactate or other cytochemical markers to differentiate between viral and bacterial meningitis? Do you send anything beyond a standard meningitis panel for immunocompetent patients? When and what?
4.) When do you admit a patient, post-LP, who appears to have viral meningitis? What anti-microbial agents do you administer these patients, if any?
EM Lyceum 
Thanks for your comment and for reading. All meningitis can be very difficult to diagnose. Viral meningitis is really many different disease entities, and we use it here as an umbrella term, to differentiate from the commonly much more serious bacterial meningitis.