The evaluation of someone who may have bacterial meningitis begins with a history and physical examination.

Physical findings in those with bacterial meningitis may include:

• Brudzinski sign:
• Bending of the neck causes the hips and knees to bend
• Confusion
• Lethargy:
• A condition of excessive sleepiness or drowsiness.
• Fever
• Kernig sign:
• Extending the knees with the hips flexed causes pain and muscle spasms
• Papilledema:
• Increased pressure in the eyes
• Meningococcal rash:
• Meningococcal infection may cause a rash that looks like broken blood vessels.

Testing is necessary to confirm the diagnosis of bacterial meningitis.

Testing for bacterial meningitis may include:

• Spinal tap:
• This is the most important test to diagnose meningitis
• Encephalitis or meningitis may cause the spinal fluid to become cloudy
• The fluid can be rapidly tested for the presence of bacteria
• CT scan of the brain
• MRI scan of the brain
• Blood cultures
• Complete blood count
• Serologic tests for certain bacteria, fungi and viruses