Favorable outcome in postoperative meningitis hinges upon early recognition of this complication. As postoperative fever is common and headache is ubiquitous immediately following surgery, much clinical judgment is required. Nuchal rigidity, a hallmark of meningitis diagnosis in most settings, may be difficult to evaluate following AN surgery as a result of surgical trauma to the cervical musculature. As a general rule, the clinician is wise to have a low threshold for performing a lumbar puncture when a suspicion of meningitis arises. Interpretation of CSF findings following AN surgery is complicated by the pleocytosis which normally follows posterior fossa craniotomy.
Aseptic meningitis is even more common than bacterial in the postoperative AN patient.
Conversely, when the clinical index of suspicion is high, intravenous antibiotics should be commenced despite relatively benign CSF findings and continued until the culture results become known. Adequate treatment of post-surgical bacterial meningitis requires a minimum of 7 days of intravenous antibiotics. Aseptic meningitis usually commences somewhat later than infectious cases. Symptoms may be rapidly ameliorated by administration of a course corticosteroids. In some cases, symptoms recur with withdrawal of corticosteroids.