A child is brought to the emergency depament with signs of meningeal irritation. She had suppurative otitis media in the last week. Infection of middle ear can spread to CNS through:
Venous plexus
Cochlear aqueduct
Cochlear nerve sheath
Bloodstream
In the setting of middle ear infection, bacterial infection can invade through the round window causing acute suppurative labyrinthitis. From the labyrinth, bacteria gain access to the cochlear aqueduct, forming a conduit between the perilymph and the cerebrospinal fluid (CSF) resulting in meningeal infiltration.