Whether there would be evidence eight months later depends on the type of
meningitis. A simple
viral infection would likely have completely cleared. But, 9 months later, if there was still signs on LP, I would worry about there being an "ongoing" infection.
The signs of meningitis on an LP are, elevated protein, sometimes low glucose, and the presence of more than a couple white cells. From 10 or 20 to many thousands in the really bad ones.