Subacute and chronic meningitis

[Dianne]

Subacute meningitis is inflammation of the layers of tissue that cover the brain and spinal cord (meninges) and of the fluid-filled space between the meninges (subarachnoid space) when it develops over days to a few weeks. Chronic meningitis is slowly developing meningitis that lasts 4 weeks or longer.

Many infections and disorders that cause inflammation can cause chronic meningitis.
Having a weakened immune system increases the risk of developing chronic meningitis.
Symptoms are usually similar to those of acute bacterial meningitis (headache, fever, and stiff neck) but may also include confusion, hearing loss, and double vision.
To diagnose chronic meningitis, doctors usually do imaging of the head, such as magnetic resonance imaging (MRI), followed by a spinal tap (lumbar puncture) with analysis of the cerebrospinal fluid.
The cause is treated.

(See also Introduction to Meningitis.)
The brain and spinal cord are covered by three layers of tissue called meninges. The subarachnoid space is located between the middle layer and the inner layer of the meninges, which cover the brain and spinal cord. This space contains the cerebrospinal fluid, which flows through the meninges, fills the spaces within the brain, and helps cushion the brain and spinal cord.
Subacute meningitis develops over a longer period of time than acute meningitis and over a shorter period than chronic—over a few weeks. Its causes, symptoms, diagnosis, and treatment are similar to those of chronic meningitis. Bacterial meningitis may be subacute rather than acute.
Chronic meningitis develops slowly, over weeks or longer, and may last for months to years. Rarely, chronic meningitis causes only mild symptoms and resolves on its own.