Meningitis

Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.

Brudzinski's sign of meningitis

One of the physically demonstrable symptoms of meningitis is Brudzinski's sign. Severe neck stiffness causes a patient's hips and knees to flex when the neck is flexed.

Kernig's sign of meningitis

One of the physically demonstrable symptoms of meningitis is Kernig's sign. Severe stiffness of the hamstrings causes an inability to straighten the leg when the hip is flexed to 90 degrees.

Lumbar puncture (spinal tap)

A lumbar puncture, or spinal tap, is a procedure to collect cerebrospinal fluid to check for the presence of disease or injury. A spinal needle is inserted, usually between the 3rd and 4th lumbar vertebrae in the lower spine. Once the needle is properly positioned in the subarachnoid space (the space between the spinal cord and its covering, the meninges), pressures can be measured and fluid can be collected for testing.

Meninges of the brain

The organs of the central nervous system (brain and spinal cord) are covered by 3 connective tissue layers collectively called the meninges. Consisting of the pia mater (closest to the CNS structures), the arachnoid and the dura mater (farthest from the CNS), the meninges also support blood vessels and contain cerebrospinal fluid. These are the structures involved in meningitis, an inflammation of the meninges, which, if severe, may become encephalitis, an inflammation of the brain.

Meninges of the spine

The organs of the central nervous system (brain and spinal cord) are covered by 3 connective tissue layers collectively called the meninges. Consisting of the pia mater (closest to the CNS structures), the arachnoid and the dura mater (farthest from the CNS), the meninges also support blood vessels and contain cerebrospinal fluid. These are the structures involved in meningitis, an inflammation of the meninges, which, if severe, may become encephalitis, an inflammation of the brain.

Haemophilus influenza organism

This is a gram stain of spinal fluid from a person with meningitis. The rod-like organisms seen in the fluid are Haemophilus influenza, one of the most common causes of childhood meningitis (prior to the widespread use of the H. influenza vaccine). The large red-colored objects are cells in the spinal fluid. A vaccine to prevent infection by Haemophilus influenza (type B) is available as one of the routine childhood immunizations (Hib), typically given at 2, 4 and 12 months.

Causes

Symptoms

Exams and Tests

Treatment

Outlook (Prognosis)

Possible Complications

When to Contact a Medical Professional

Prevention