Viral Infection Intro

Question 1

Herpes-Zoster (Shingles)

Answer 1

-Herpes/zoster = old
-Chickenpox/varicella = young

CF
-Unilateral RASH
-Vesicles, crust over, pain

50/50/50 rule, 50+ age, 50 hours or less onset, 50+ lesions

Question 2

Herpes-Zoster TX

Answer 2

ACYCLOVIR
-Mild: 800 PO 5x/day for 7-10 days
-M/Sev: 10-15 mg/kg IV Q8 for 10-14 days

VALACYCLOVIR
-1000 mg PO TID

FAMICICLOVIR
-500-750 mg PO TID

Question 3

HZ Prevention

Answer 3

Herpes Zoster Vaccine
-Shingrix IM

Two doses (0.5ml) of RZV 2-6 months apart for all adults 50+
-AE: can have allergic rxn

Question 4

Herpes Simplex Virus Encephalitis

Answer 4

Rapid onset
-Fever
-CNS: HA, lethargy, confusion, FND, aphasia, seizures

Diagnosis
-WBC 20-300
-Normal glucose
-PCR for HSV DNA
-CT, MRI (edema, lesions)

Question 5

HSV Encephalitis TX

Answer 5

Start ASAP

ACYCLOVIR
-10 mg/kg IV Q8 hr for 14-21 days
-no oral tx
-infuse slowly over 1 hr
-preg cat b, can be used
-reduce dose if GFR <50

Question 6

Acyclovir AE

Answer 6

-SJS, toxic epidermal
-Thrombocytopenic purpura
-Renal failure
-Neurotoxicity
-NVD, headache
-Hypotension
-Pain at injection site

STERNN HPH

DC if HSV CSF PCR negative after 72 hr tx (normal mental status and normal CT/MRI)

Question 7

Acyclovir-Resistant HSV Strains

Answer 7

Consider
-Ganciclovir
(caution in HSV2 AIDS)
-Foscarnet

Question 8

Encephalitis Supportive TX

Answer 8

Mannitol

Dexamethasone
-ae: high ICP, convulsions, vertigo, HA

Question 9

CMV RF

Answer 9

Immunocompetent
-few if any sx

Immunocompromised
-solid organ transplant (1 yr)
-HIV

Question 10

CMV TX

Answer 10

Immunocompetent
-self limiting not requiring viral tx

Immunocompromised
-Ganciclovir (IV/PO)
-Valganciclovir (PO)
-Foscarnet (IV)
-Cidofovir (IV)
-Maribavir (PO), good for resistant/refractory

MCV is my GF

**Letermovir (IV) for prophylaxis

Question 11

CMV Disease (not infection)

Answer 11

Non-severe disease
-Valganciclovir 900 mg BID
-Alt: Ganciclovir 5mg/kg IV Q12

Severe
-Ganciclovir 5mg/kg IV Q12
-Alt: Valganciclovir 900 mg BID

CMV Retinitis
-cidofavir, gan, val, fos, lido, mari

Question 12

Ganciclovir AE

Answer 12

-Heme: neutropenia, anemia, thrombocytopenia
-GI: NVD, pain, flatulence
-Nephrotoxicity
-Retinal detachment
-Neuro: HA, confusion, hallucin, seizures
-Carcinogen, teratogen, mutagen
-Inhibits spermatogenesis

GRHNKS

Question 13

Valganciclovir AE

Answer 13

-like gan
-myelosuppression tho

Question 14

Ganciclovir Resistance

Answer 14

Low
-continue gan 12 mg/kg every 12 hr

High
-Foscarnet 90 mg/kg Q12
-Maribavir 400 mg BID
-Cidofovir 5 mg/kg IV Q2weeks

Question 15

Foscarnet AE

Answer 15

-GI, anemia, HA
-Nephrotoxicity
-Electorlyte: Low MCK, High/low Phos
-Seizure

SHAKE G

Question 16

Cidofovir AE

Answer 16

-Heme (NAT)
-Nephrotoxicity
-Neuro
-Opthalmic (iritis, uveitis)
-Respiratory (CDP)
-Fever, alopecia, rash

NON FARH

Question 17

Maribavir AE

Answer 17

GI; taste disorder, NVD

Question 18

Duration/Monitoring

Answer 18

Until resolution of viremia (14-28 days)

Prophylaxis: 1 to 3 month oral Val QD

Monitor weekly viral load

Question 19

Acronyms

Answer 19

ZOSTER = AVF

HSV = ACY (res = GF)

CMV = CMV is my GF