Bacterial meningitis is an uncommon complication of pituitary macroadenoma. Bacterial meningitis can occur in patients with pituitary macroadenoma who have received sphenoidal surgery or had cerebrospinal fluid (CSF) rhinorrhea. A 62-year-old male visited our hospital for headache and fever. Brain magnetic resonance imaging showed a pituitary macroadenoma. CSF study revealed acute bacterial meningitis. Intravenous antibiotics and hydrocortisone replacement therapy were started, and lead to good clinical outcome. Bacterial meningitis should be considered in patients with a pituitary macroadenoma who present with meningitis symptoms, even though in the absence of rhinorrhea or surgical history.

Retrospective analysis was conducted on the clinical data of 38 cases of bacterial meningitis that were proven by cerebrospinal fluid culture. Each case occurred by GBS (68.4%), Pneumococcus (15.8%), E. coli (5.3%), Streptococcus mitis (5.3%), Streptococcus bovis (2.6%), and Staphylococcus xylosus (2.6%). Compared to 28 cases with normal outcome, 10 cases who died or had adverse outcomes at hospital discharge were more likely to present with coma, seizure (before or within admission, focal, status epilepticus), require pressor or ventilator support, have initial peripheral blood leukocyte count less than 4,000/mm3 or neutrophil count less than 1,000/mm3, and have hydrocephalus or cerebral infarction by brain imaging.