CNS Infections

Question 1

What are some causes of a brain abscess?

Answer 1

1. Contiguous spread
2. Hematogenous seeding w/ bacteremia
3. Trauma
4. Cryptogenic

Question 2

What are the clinical manifestations of a brain abscess?

Answer 2

Presence of headache, seizures, nausea and vomiting, and focal neurologic signs
Uncommon: fever, nuchal rigidity

Question 3

What diagnostic tests are commonly performed for brain abscesses?

Answer 3

MRI & CT Scan commonly ordered, blood cultures for bacteremia
LP should NOT be performed (risk herniation)

Question 4

What are some features of a paraspinal abscess?

Answer 4

Usually due to bacteremia (staph aureus most common); requires surgical drainage to prevent cord compression; osteomyelitis of vertebral bodies

Question 5

What are the most common locations of a paraspinal abscess?

Answer 5

Posterior & thoracolumbar > cervical

Question 6

What are some infectious etiologies of chronic meningitis?

Answer 6

Tuberculosis, cryptococcus, lyme disease, syphilis, coccidioidomycosis, histoplasmosis

Question 7

What are features of the general paresis type neurosyphilis?

Answer 7

Personality, affect, reflexes, eye symptoms, sensorium, intellect, speech abnormalities

Question 8

What are features of the tabes dorsalis type neurosyphilis?

Answer 8

Ataxia, shooting pains, sphincter disturbance, peripheral neuropathy, cranial neuropathies

Question 9

What is neurocysticercosis?

Answer 9

Brain infection caused by infection with Taenia solum (tapeworm in pigs)

Question 10

What are some noninfectious etiologies of chronic meningitis?

Answer 10

Neoplasms, sarcoidosis, vasculitis, drug induced (NSAIDs)

Question 11

What are the differences between meningitis and encephalitis?

Answer 11

Meningitis - no altered mental status & infection of meninges
Encephalitis - altered mental status & infection of brain
CSF exam similar in both

Question 12

What are some etiologies of encephalitis?

Answer 12

Viral (HSV - common), bacterial pathogens, spirochetes, parasites, drugs, vasculitis, mycoplasma…

Question 13

What is acute disseminated encephalomyelitis (ADEM)?

Answer 13

Postinfectious encephalitis occurring 5-21 days after a viral illness; multifocal neurologic symptoms
Treatment: glucocorticoids –> complete recovery

Question 14

What type of organism often infects diabetics with uncontrolled sugar levels?

Answer 14

Mucor (Fungus)

Question 15

What type of brain abscess is related to frontal sinus disease and osteomyelitis?

Answer 15

Cranial epidural abscess

Question 16

Is a subdural abscess a medical emergency?

Answer 16

Yes. Headaches and seizures are common signs

Question 17

A patient’s blood work is positive for staph bacteremia and currently is running a 103 fever and reports of severe back pain limiting her walking. What is your first suspected diagnosis?

Answer 17

Paraspinal abscess

Surgical drain required

Question 18

What lab test would you do for a suspected case of lyme meningitis?

Answer 18

Synthesis index. Antibodies in the CSF will be greater than that in the serum.

Question 19

What does your CSF values look like with viral encephalitis?

Answer 19

Increased lymphocytes

Cell count 500 seen in HSV, CTFV, CEV

Question 20

HSV-1 is the most common etiology of Herpes Encephalitis. What is a unique symptom / sign in patients with this?

Answer 20

Seizures / status epilepticus –> temporal lobe affected often

Question 21

Your patient presents with acute hemorrhagic encephalitis. His friend says they had been swimming in the lake nearby. What do you diagnose?

Answer 21

Encephalitis due to naegleria fowleri

CSF: High PMN / low glucose
99% mortality

Question 22

How is Creutzfel Jakob Disease spread and what are some signs?

Answer 22

CJD is spread by cadaveric tissue.

You see myoclonus, cerebellar ataxia, and dementia.