CNS infections

Question 1

What are the common symptoms of meningitis?

Answer 1

Fever, headache, neck stiffness, photophobia, and change in mental status

Question 2

What are the classic signs of meningitis?

Answer 2

Change in mental status and meningeal signs: Kernig’s sign, Brudzinski’s sign, and nuchal rigidity

Question 3

What test is necessary to make the diagnosis of meningitis?

Answer 3

CSF analysis (usually obtained by LP)

Question 4

>1000 polymorphonuclear leukocytes, ↓ glucose, ↑ protein, ↑ CSF pressure

Answer 4

Bacterial meningitis

Question 5

Increased lymphocytes, minor elevation in protein, normal CSF pressure

Answer 5

Viral meningitis

Question 6

Increased lymphocytes, minor elevation in protein, dramatically ↓ glucose, elevated CSF pressure

Answer 6

Fungal meningitis

Question 7

Increased lymphocytes, ↑ protein, ↓ glucose

Answer 7

TB meningitis

Question 8

Name the most common bacterial pathogens responsible for causing meningitis and the appropriate treatment (Tx) for each of the following demographic groups:

1 month

Answer 8

Group B strep (commonly Streptococcus agalactiae), Escherichia coli, and Listeria

Empiric Tx: second-generation cephalosporin and ampicillin

Note: there are other acceptable empiric antibiotic regimens.

Question 9

Name the most common bacterial pathogens responsible for causing meningitis and the appropriate treatment (Tx) for each of the following demographic groups:

1-3 months

Answer 9

Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae (less common today due to vaccinations)

Empiric Tx: second-generation cephalosporin, vancomycin, and steroids

Question 10

Name the most common bacterial pathogens responsible for causing meningitis and the appropriate treatment (Tx) for each of the following demographic groups:

3 months to adulthood

Answer 10

S. pneumoniae (most common cause of meningitis in adults), N. meningitidis

Tx: third-generation cephalosporin, vancomycin, and steroids

Question 11

Name the most common bacterial pathogens responsible for causing meningitis and the appropriate treatment (Tx) for each of the following demographic groups:

Associated with surgery or trauma to the CNS

Answer 11

Staphylococcus aureus

Tx: Vancomycin and ceftazidime

Question 12

Name the most common bacterial pathogens responsible for causing meningitis and the appropriate treatment (Tx) for each of the following demographic groups:

Adults >60 with chronic illness (including alcoholics)

Answer 12

S. pneumoniae, gram-negative bacilli, Listeria

Tx: third-generation cephalosporin, ampicillin, and steroids

Question 13

Name seven complications of meningitis:

Answer 13

1. Hyponatremia
2. Seizures
3. Subdural effusion (especially with H. influenzae meningitis)
4. Cerebral edema
5. Subdural empyema
6. Brain abscess
7. Ventriculitis

Question 14

Argyll-Robertson pupil

Answer 14

Syphilis

Question 15

Latin American immigrant with seizures

Answer 15

Neurocysticercosis (due to Taenia solium)

Question 16

Lymphocytic meningitis, cranial neuropathy, and erythema chronicum migrans

Answer 16

Lyme disease

Question 17

Maternal exposure to cat feces

Answer 17

Toxoplasmosis

Question 18

Most common cause of viral encephalitis

Answer 18

Herpes simplex encephalitis

Question 19

Presents in childhood; elevated gamma globulin and measles antibodies in CSF

Answer 19

Subacute sclerosing panencephalitis

Question 20

Progressive dementia and myoclonus due to abnormal isoform of prion protein

Answer 20

Creutzfeldt-Jakob disease

Question 21

Most common type of fungal meningitis; commonly seen in immunosuppressed patients; birds are the host for the pathogen

Answer 21

Cryptococcal meningitis

Question 22

Paresis and tabes dorsalis (sensory ataxia)

Answer 22

Syphilis

Question 23

Ring-enhancing lesions associated with focal neurologic deficits

Answer 23

Toxoplasmosis

Question 24

+ India ink preparation

Answer 24

Crytococcal neoformans

Question 25

Subacute onset of hemiplegia or visual deficits in an AIDS patient

Answer 25

Progressive multifocal leukoencephalopathy (caused by JC virus)

Question 26

What CNS infection commonly presents with fever, signs of ↑ ICP, focal neurologic signs, and a ring-enhancing lesion on CT?

Answer 26

Brain abscess

Question 27

What are the organisms most commonly responsible for brain abscesses?

Answer 27

Anaerobes, gram-positive cocci, gram-negative rods

Question 28

What is the recommended empiric antibiotic coverage for brain abscess?

Answer 28

Metronidazole and ceftriaxone (or another third-generation cephalosporin)