Viral skin Flashcards
What are the three major skin ailments due to viruses?
- Papillomas
- Ulcers/purulent lesions
- Childhood rash and fever
What are the two viruses that cause papillomas/nodules?
HPV and molluscum
What are the three viruses that cause ulcers/purulent lesions?
Herpes
Chicken pox
Small pox
What are the four viral causes of childhood rash and fever?
Measles
German measlses
Roseola
Fifth disease
How are skin infections via viruses infected?
Virus infects other systems, causes viremia
Viruses direct infection of the skin
What are the two types of skin lesions caused by viruses? What causes them?
Infectious and noninfectious
Infex = viral replication
Non-infex = immune response
What is a papilloma?
Benign growth on the surface of the skin or mucous membrane
Hyperkeratosis, and koilocytes, are found with what skin lesion?
Warts
Are cutaneous warts painful?
Generally not
What is the virus that causes warts?
HPV
What are verruca vulgaris? How do these appear?
Common warts
Rough, cauliflower on hands and feet
What are verruca plantaris? How do these appear?
Plantar warts
Grows inward, appears as only thickened keratin layer with punctate hemorrhages
What are verruca plana? How do these appear?
Facial warts, smooth
What is the virus family of HPV? Genome? enveloped?
papovaviridae
Non-enveloped
dsDNA
What cell layer actually has virions in them in HPV infections?
Suprabasal layer
What cell layer become infected by virions in HPV infections?
Basal layer of the epidermis
What are the histological characteristics of a wart relative to normal skin? What causes this?
Each layer is expanded d/t increased virus signal to grow
What are the two cell proteins that activate the cell cycle? How does each do its thing?
HPV E7 and E6
E6 inhibits p53
E7 inhibits Rb
How are viral HPV classified?
Mucosal(anogenital)
Cutaneous (common and plantar)
How are warts transmitted?
Direct contact with a wart or contaminated surface
What specific surface is particularly prone to transmit warts?
Non-slip shower mats
How do you diagnose warts?
Clinical appearance
Koloidal cells
How do Koilocytes appear?
Nucleus surrounded by a halo of unstained section
How do you treat plantar warts? (3)
Cryotherapy
Cytotoxic chemicals
Surgical removal
What are the HPV strains that cause high risk angogenital warts?
16
18
31
33
What are the HPV strains that cause low risk angogenital warts?
6
11
What are the HPV strains that cause plantar warts?
1
4
What are the HPV strains that cause common warts?
2
3
10
Do the HPV vaccine protect against cutaneous warts? Genital warts?
Not for common, but yes for genitals
How does Mollusum contagiosum appear? (3) Pain?
Painless
Pearly
Umbilicated (central depression)
Nodules
Where on the body is moluscum contagiosum found for adults?
Sexy areas
What are molluscum bodies?
Large, eosinophilic cytoplasmic inclusion bodies found in molluscum contagiosum
What is the virus that causes molluscum contagiosum?
Molluscum contagiosum virus
What is the family of Molluscum contagiosum virus? Genome? Enveloped?
Poxviridae
Large dsDNA
Where does Molluscum contagiosum virus replicate?
within cytoplasm
How is Molluscum contagiosum transmitted?
Direct contact with lesions
Fomite transmission
What is the treatment for Molluscum contagiosum virus? Are they self limiting?
Surgery or cryotherapy
Self limiting
Are herpes labialis (cold sore) painful?
Yes
What is primary herpetic gingivostomatitis?
Herpes ulcers on the gingiva. very painful
What is the ocular disease caused by HSV? Initial and chronic symptoms?
Herpes simplex keratitis
Inital symptoms = conjunctivitis
Chronic = scar tissue in the cornea
What is the brain disease caused by HSV?
Herpes simplex encephalitis
What is herpetic whitlow?
Digital infection with herpes
What is the family of herpes virus? Genome? Enveloped?
Herpesviridae
Enveloped
dsDNA
What are the two phases of herpes virus?
Latent phase
Lytic phase
Recurrent cold sores are caused by latent herpes from what nerve?
Trigeminal nerve
What are the two serotypes of HSV? What does each cause?
HSV 1 = oral lesions
HSV 2= Genital
How is HSV transmitted?
Direct contact with lesions or saliva
What is the treatment for herpes? How does this work?
Acyclovir – viral thymidine kinase activates it, and it inhibits DNA pol
What is the virus that causes chickenpox?
Varicella virus (VZV)
What are the symptoms of varicella infx?
Central rash and fever
What are the lesions like in chickenpox? Evolution? Do these lesions evolve together, or separately?
Vesicles to pustules to scabs
Lesions evolve separately
Are lesions with chicken pox seen on the soles of feet or palms of the hands?
Very rarely
What are the complications with chicken pox? (2)
Bacterial infections of the lesions
Pneumonia
What happens to neonates born to mothers with primary chickenpox infection?
Low birthweight
Microcephaly
What is the prodrome of herpes zoster (shingles)?
Paresthesia
How is herpes zoster reactivated?
Immunosuppression of some sort
What are the complications of untreated herpes zoster?
Postherpetic neuralgia
What is the distribution of herpes zoster?
Dermatomal
What is the viral family of varicella-zoster virus? Enveloped? genome?
Herpesviridae
Enveloped
dsDNA
What are the two sensory nerves (or group of nerves) that often hold VZV?
Dorsal route
Trigeminal ganglia
How many serotypes of VZV?
One
How is VZV transmitted (2)?
Respiratory secretions/saliva
Direct contact with lesions
How do you diagnose VZV? (3)
Tzanck smear
Serological testing
Latex agglutination
What are the two vaccines for varicella?
Varicella vaccine
Zoster vaccine
What does the varicella vaccine contain? How is it prepared?
Live attenuated virus strain grown in tissue culture
When is the varicella vaccine given?
1 at 12-15 mo
2 at 4-6 yrs
What does the zoster vaccine protect against? What does it contain? What is it used for?
Reactivations of VZV
Higher titer of live attenuated virus like varicella vaccine
Used to prevent shingles for previously infected individuals
What is the treatment for VZV? How sensitive is VZV relative to other HSVs?
Acyclovir
less sensitive
What is a Tzanck smear? What is this used to diagnose?
Smear looking for multinucleated, diagnostic of Herpes.