Bacterial meningitis in older adults.

The burden of disease due to bacterial meningitis is shifting toward older adults. Clinicians should maintain a high level of suspicion of meningitis in older adults, since they may present without classic signs and symptoms. Clinicians should remember that more older patients are at risk of healthcare-associated meningitis and may be at risk of more resistant organisms. A lumbar puncture should be performed as quickly as possible. If a CT scan is required before the lumbar puncture, blood cultures should be drawn and appropriate empiric antibiotics should be started before sending the patient to the CT scanner. Empiric antibiotics should be chosen based on patient history, review of patient's known illnesses and risk factors, results of CSF Gram stain, and local institution antibiotic resistance patterns. Clinicians should remember that Streptococcus pneumoniae may be resistant to penicillin and cephalosporins, so vancomycin is usually also administered until the bacterial resistance pattern is known. Adjunctive dexamethasone may be started before or at the time of antibiotic therapy based on risk versus benefit analysis, and may be discontinued if patient is found to not have Streptococcus pneumoniae meningitis.