Meningitis is occasionally caused by noninfectious conditions (eg, noninfectious disorders, drugs, vaccines). Many cases of noninfectious meningitis are subacute or chronic.
Some Noninfectious Causes of Meningitis
Noninfectious meningitis causes symptoms (eg, headache, fever, nuchal rigidity) that are similar to those caused by other kinds of meningitis. Severity and acuity can vary, but noninfectious meningitis tends to be less severe than acute bacterial meningitis.
Diagnosis of noninfectious meningitis is based on analysis of CSF obtained by lumbar puncture (preceded by neuroimaging if increased intracranial pressure or an intracranial mass effect is suspected). CSF findings may include
Causative disorders are treated, and causative drugs are stopped. Otherwise, treatment is supportive.
If patients appear seriously ill, appropriate antibiotics and corticosteroids are started immediately (without waiting for tests results) and continued until acute bacterial meningitis is ruled out (ie, CSF is shown to be sterile).