Hi, I suspect there was a slight bit of miscommunication/misunderstanding of what was going on since encephalitis cannot be diagnosed using a scope into the sinuses. However, sinusitis can be diagnosed in that way and would also explain why you were given the antibiotic. Encephalitis is a serious illness which requires hospitalization and it would be doubtful you would even be able to think clearly let alone write a question such as this on a computer if that s what you really had. Don t forget to drink lots and lots of fluid which will help resolve the infection. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Dariush Saghafi, Neurologist