Meningitis

Meningitis is inflammation of the membranes (meninges) covering the brain and the spinal cord. Although the most common causes are infection (bacterial, viral, fungal or parasitic), chemical agents and even tumor cells may cause meningitis. Encephalitis and brain abscess can complicate infective meningitis.

Causative organisms

Viruses are the most common cause of meningitis.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Major bacteria that cause meningitis are Neisseria meningitidis (meningococcus), Streptococcus pneumoniae (pneumococcus), and Haemophilus influenzae. Less common bacterial causes include Listeria monocytogenes, Staphylococcus and Escherichia coli. In developing countries, Mycobacterium tuberculosis is a common cause of bacterial meningitis.

Related Topics:
Neisseria meningitidis - Streptococcus pneumoniae - Haemophilus influenzae - Listeria - Staphylococcus - Escherichia coli - Mycobacterium tuberculosis

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Streptococcus agalactiae is an important cause of neonatal meningitis associated with a high mortality rate.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

In immunocompromised patients, fungal meningitis may occur, typically caused by Cryptococcus neoformans.

Related Topics:
Immunocompromised - Cryptococcus

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Non-infectious causes include:

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

• Tumors
• Leukemia
• Lymphoma
• Brain tumors
• Brain metastasis
• Sarcoidosis
• Drugs
• Intrathecal drugs
• Methotrexate
• Lead poisoning