5th August 2024

Bacterial meningitis

Bacterial meningitis is a rare but life-threatening condition which is more common in very young and elderly people. The most common causative organisms include Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae and Listeria monocytogenes. The most severe symptoms are typically seen in meningococcal infection, with patients presenting with septic shock and the characteristic non-blanching rash (Figure 1). Listeria monocytogenes usually affects those who are at the extremes of age, immunocompromised or pregnant.

Treatment of bacterial meningitis

• In suspected bacterial meningitis, empirical antibiotic treatment should be initiated immediately.
• Due to the severity of the infection, cases of suspected meningococcal meningitis in the community should be treated with benzylpenicillin before transfer to hospital.
• For adults <50 years, empirical antibiotic treatment in the hospital consists of cefotaxime or ceftriaxone.
• For those >50 years, amoxicillin should be added to cover for Listeria.
• In suspected pneumococcal meningitis, dexamethasone should be started no later than 12 hours after the 1st antibiotic dose, as it has been shown to reduce mortality.
• The antimicrobial regime should then be reviewed with the CSF results and adjusted accordingly.
• Antimicrobial chemoprophylaxis is indicated for close contacts of those with confirmed meningococcal meningitis. Close contacts include household members, intimate contacts and anyone who has spent more than 8 hours less than 3 feet away from the person from 7 days before the onset of their symptoms to 24 hours after starting antibiotics. It also includes those who have had direct exposure to the patient’s oral secretions (for example, during intubation or suctioning) during this period.