Viral infections Flashcards
Where do RNA viruses invade?
Single stranded RNA viruses invade and repilicate in the cytoplasm
Where do DNA viruses invade?
Invade and repilcate in the nucleus
Where do retroviruses invade?
Use reverse transcription to create a DNA copy of their RNA genome and insert it into the host cell to become part of the host RNA.
What are the steps of viral infection?
Virus attaches to the host cell
Viral DNA/RNA enters cell and replicates
Viral particles are created
Host cell dies and releases new viruses
In general, HSV 1 affects the ____ region and HSV 2 affects the ____ region.
Oral
Genital
What are risk factors for HSV?
Women
h/o STDs
Multiple sexual partners
Contact with sex workers
Women who have sex with women
What does HSV 1 look like?
Singular or grouped vesicles forming crusts and moist ulcers on the lips nares and mouth. Can also have a herpetic whitlow (digital vesicular lesions) from biting fingers
What does HSV 2 look like?
Multiple vesicles forming crusts and ulcers on the external genitalia, vaginal canal, and perianal region. Painful and itchy
What are other symptoms of HSV 1?
Pain with eating
swollen lymph nodes
low grade fever
What are other symptoms of HSV 2?
Dysuria
Cervicitis
Urinary retention
swollen lymph notes
fever, body ache
What can cause HSV flares?
- Fevers
- Hormones
- Stress
- Sunlight
What is HSV keratoconjunctivits?
HSV infection in the eye.
Presents as pain, FB sensation, photophobia, and swelling and redness of eyelid
Typically unilateral.
Can lead to blindness.
What are the two ways that you can get HSV keratoconjuctivitis?
- Trigeminal nerve spread
- Via birth
What else cane HSV cause (esp in immunocompromised patients)?
- HSV encephalitis
- Disseminated (PNA)
- Esophagitis
- Proctitis
How do you diagnose HSV?
Typically clinically but you can culture or do a Tzanck smear
What does a Tzanck smear tell you?
Shows multinucleated giant cells. Patient has HSV 1, HSV 2, or varicella
How do you diagnosed HSV keratoconjunctivitis?
Use fluorescein stain and slit-lamp to look for dendritic lesions
How long do HSV outbreaks last?
10-20 days initially
5-10 days with recurrences
What do antivirals do for HSV infections?
Do not cure.
Reduce duration and severity.
What can you give a patient for topical HSV-1?
Sucrets
Anbesol
Magic mouthwash
What is the MOA for antivirals?
Inhibit viral DNA synthesis and replication
Which antivirals are prodrugs?
valacyclovir and famciclovir
Where is acyclovir metabolized?
Liver
How are antivirals excreted?
Renally, caution in renal failure
