Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae are all common bacterial causes of meningitis.

Enteroviruses are the most common viral cause of meningitis.

Headache, fever, and stiff neck are all common symptoms of meningitis.

Herpes simplex virus is the most common cause of encephalitis.

Altered mental status, seizures, and focal neurological deficits are all common symptoms of encephalitis.

Streptococcus pneumoniae is the most common cause of brain abscess.

Headache, fever, and focal neurological deficits are all common symptoms of brain abscess.

Streptococcus pneumoniae is the most common cause of subdural empyema.

Headache, fever, and focal neurological deficits are all common symptoms of subdural empyema.

Staphylococcus aureus is the most common cause of epidural abscess.

Headache, fever, and focal neurological deficits are all common symptoms of epidural abscess.

Viral infection is the most common cause of transverse myelitis.

Weakness in the legs, sensory loss in the legs, and bladder and bowel dysfunction are all common symptoms of transverse myelitis.

Campylobacter jejuni infection is the most common cause of Guillain-Barre syndrome.

Weakness in the legs, sensory loss in the legs, and difficulty breathing are all common symptoms of Guillain-Barre syndrome.