CNS Infection Review

Question 0

What are polyomaviruses?

Answer 0

• circular dsDNA of 5000bases
• early T - large: cell rep, small - viral DNA rep
• late, 3 capsid protein: VP1, 2, 3
• JC and BK

Question 1

What is the diff for encephalitis?

Answer 1

1. Alphaherpes viruses: HSV, VZV
2. Post infectious immune responses
3. TB
4. Autoimmune
5. Enteroviruses
6. Minor or rare: arboviruses

Question 2

How are polyomaviruses spread and taken in?

Answer 2

• respiratory or oral
• tonsils and lympnodes
• viremia to kidneys early in life
• asymptomatic
• persistent and latent

Question 3

What happens in immunocompromized Pxs with JC virus?

Answer 3

• deactivated and travels to the brain

- causes PML, slow virus

Question 4

When you hear subacute sclerosing panecephalitis what do you think?

Answer 4

Measles

Question 5

Where does BK multiple and go?

Answer 5

Multiplies in urinary tract –> possible hemorrhagic cystitis

Question 6

What is PML, and what is it caused by?

Answer 6

Progressive multifocal leukoencephalopathy (JC)

• demyelinated white matter
• JC transforms astrocytes and kills oligodendros

Question 7

What is the treatment for JC virus?

Answer 7

Cidofovir

- decrease immunosuppression

Question 8

What are laboratory diagnoses of polyomaviruses?

Answer 8

• In situ immunofluorescense
• PCR of CSF, urine, or biopsy material
• urine cytologic tests revealing enlarged cells with dense basophilic intranuclear inclusions resembling cytomegaloviruses

Question 9

How do you diagnosis viral encephalopathy?

Answer 9

• low grade fever
• confusion and focal neurological defects
• WBC, CBC, blood gases, serum chem is normal
• MRI: irregular areas of hemorrhagic necrosis (temporal lobe for HSV)
• LP: CSF lymphocytes,RBC present, normal glucose, elevate protein
• virus isolation, serology of antibodies against virus, PCR

Question 10

What does acyclovir do?

Answer 10

Chaim termination

• needs wild type thymidine kinase
• Used for HSV and VSV
• resistance is from mutations in thymidine kinase or viral DNA pol
• 100X binding

Question 11

What does trifluridine do?

Answer 11

Altered base pairing

• targets any cell undergoing a high rate of replication
• component of Experiemental cancer drugs

Question 12

How are the structures of acyclovir and ganciclovir different?

Answer 12

Acyclovir - one OH
Ganciclovir - two OH
Both are from guanine

Question 13

What is the structure of trifluridine?

Answer 13

T base with CF3 instead of CH3

Question 14

What does Ganciclovir do?

Answer 14

• beta herpes viruses with no thymine dine kinase
• 30X binding
• HCMV retinitis and other HCMV infections