monday - more D and P - infectious disease summary

Question 1

Encephalitis differential

Answer 1

Alphaherpesviruses:
HSV
VZV

Postinfectious immune responses (Measles, mumps, ruebella, VZV, influenza)

Tuberculosis

Autoimmune disorders

Enteroviruses

Other minor / rare causes
Arboviruses
WNV, Powassan virus, La Crosse virus, etc.
Other herpesviruses (immunocompromised)
JC virus (immunocompromised)
Respiratory viruses
Rabies

Question 2

ubiquitous virus that only effects immuno-compromised patients?

what does it do in immuno-compromised patiets?

epidemiology in HIV positive patients

Answer 2

Polyomaviruses (JC and BK)

JC virus slowly spreads to the brain:

Replicates in endothelial cells of capilarries

to cause PML progressive multifocal leukoencephalopaty (partially transforms astrocytes (aborts them before it kills them) and kills oligodendrocytes)

10% of people with aids get it
90% mortality

Question 3

REVIEW

natalizumab

Answer 3

alpha4-integrin messer upper

used in MS

stops WBC’s from getting in the brain

-mab stands form monoclonal antibody

Question 4

What can be used to treat JC virus infection

Answer 4

Cidofovir

Question 5

Common physical examination findings of viral encephalitis

Answer 5

Low grade fever (<102°F)
Pulse rate, respiratory rate, and blood pressure typically normal.
Signs of confusion / focal neurological deficits.
Weakness on one side of the body.

Question 6

What viral encephalitis is more common in the fall?

winter?

Answer 6

fall - enteroviruses (polioviruses, Coxsackie A viruses (CA), Coxsackie B viruses (CB), and echoviruses)

winter - adenovirus

Question 7

What is sometimes seen on an MRI in viral encephalitis?

especially if it is herpes virus?

Answer 7

hemorrhagic necrosis (usually temporal lobe if herpes virus)

Question 8

beta herpes virus Tx

alpha herpes virus Tx

Answer 8

beta (CMV, etc) - gancyclovir (beta herpes viruses don’t have thymidine kinase)

alpha - acyclovir

Question 9

biochemical structure difference between acyclovir and gancyclovir

Answer 9

soo high yield

gancyclovir has an extra OH group in the acyclic side chain

Question 10

What viral enzyme does acyclovir need in order to work

Answer 10

viral thymidine kinase

Question 11

Trifluridine

Answer 11

thymidine analog (there are 3 fluorines where there should be 3 hydrogens on the nucleoside)

used to treat viral conjunctivitis