Pharm of CNS Infectious Diseases

Question 1

Why do we use bactericidal abx instead of bacteriostatic?

Answer 1

• because of the limited immune response in the CSF

Question 2

Drugs to reduce intracranial pressure

Answer 2

• Mannitol, hypertonic saline, corticosteroids

Question 3

Dexamethasone

Answer 3

• inhibits production of TNF and IL-1

- used to prevent neurological sequelae such as hearing loss and other neurologic deficits

Question 4

Treating bacterial meningitis in pts with no known immune deficiency

Answer 4

• MC: s. pneumo, n. meningitidis, listeria (if >50)

- vancomycin + ceftriaxone (cefotaxime) + ampicillin (if >50)

Question 5

Treating bacterial meningitis in pts with impaired cellular immunity

Answer 5

• MC: listeria, gram - bacilli (pseudomonas), s. pneumo

- Vancomycin + ampicillin + cefepime (meropenem)

Question 6

Treating healthcare associated bacterial meningitis

Answer 6

• vanco + ceftazidime or cefepime or meropenem

Question 7

Treating bacterial meningitis in beta-lactam allergy

Answer 7

• desensitize
• Vanc + moxi + TMP/SMX
• but TMP/SMX is bacteriostatic so switch once desensitized

Question 8

Do we need to cover for pseudomonas in a basilar skull fracture?

Answer 8

• No

Question 9

Cover for pseudomonas in:

Answer 9

• penetrating trauma, post-neurosurgery, CSF shunt

Question 10

Common causes of bacterial meningitis on gram stain

Answer 10

• S. pneumo : gram + diplococci
• N, meningitidis : gram - diplococci
• Listeria : gram + rods
• H. influenza : gram - coccobacilli

Question 11

Ceftriaxone contraindications

Answer 11

• in neonates because it can displace bilirubin from its binding site to albumin leading to a risk of bilirubin encephalopathy

Question 12

Viral Meningitis

Answer 12

• majority of pts will have self limited course that resolves on its own
• abx should be discontinued with culture is negative

Question 13

Fungal Meningitis

Answer 13

• Ampho B + flucytosine

- once sx start improving switch to fluconazole or voriconazole

Question 14

HSV-1

Answer 14

• MC cause of viral encephalopathy
• treat with acyclovir
• if resistance to acyclovir, treat with foscarnet bc it does not need to be phosphorylated by a viral kinase to be activated unlike acyclovir

Question 15

CMV

Answer 15

• immunocompromised
• initiate ART in HIV
• Ganciclovir + foscarnet

Question 16

Toxoplasmosis

Answer 16

• treated with pyrimethamine and sulfadiazine

- ** give leucovorin to reduce likelihood of hematologic toxicity associated with pyrimethamine