Fulminant bacterial meningitis without meningeal signs

Common clinical practice relies on the absence of neck stiffness or other meningeal signs to rule out meningitis in the alert, healthy adult. The literature does not address this specifically but implies that meningeal signs are reliable and usually present in awake patients, except infants, the elderly, and the immunosuppressed. In the following three cases two adults and a 4-year-old child, none of them immunosuppressed, presented with bacterial meningitis with no meningeal signs. In the first case, mental status was completely normal; in the second, there was only minor lethargy attributed to pain medication. In the third, lethargy was attributed to head trauma. In all three the diagnosis of meningitis was delayed up to 19 hours; lumbar puncture was performed while meningeal signs were still absent and cerebrospinal fluid analysis was grossly abnormal. All three patients had Streptococcus pneumoniae meningitis, and all three suffered massive brain damage within 24 hours of presentation and eventually died. Although the true incidence of absent meningeal signs in meningitis is unknown, the condition is rare. Clinicians cannot rely on the absence of neck stiffness to rule out meningitis, even in healthy and awake adults, and lumbar puncture should be performed whenever there is serious consideration of that diagnosis.