Viral Infections: Varicella Zoster Virus Flashcards
VZV is classified as what kind of infection?
Acute infection
VZV is mild in ___ and severe in ___
> Mild in children
> Severe in adults and immunocompromised
VZV infects what?
> Mucous membranes
> Skin
> Neurons
VZV evades the ___
Immune response
VZV causes latent infection in ____ or _____ cells.
> Dorsal root ganglia
> Surrounding satellite cells
VZV transmission is via what?
Respiratory aerosols
What causes the widespread vesicles on skin in VZV?
Hematogenous dissemination
VZV reactivation after recovery results into what? With whom do you see this presentation?
> Herpes Zoster / Shingles
Seen in:
> Immunosuppressed or older persons
> Follows dermatomes
> Most painful in dermatomes of trigeminal ganglia
Diagnosis for VZV can be done by
> Viral culture
> Antigen detection from scrapings from scabs or crusted lesions
Morphology of VZV infection
> Rash 2 weeks after respiratory infection
> Multiple waves centrifugally from the torso to the head and extremities
> Macule –> Vesicle (fluid-filled lesion) –> Rupture (leaves superficially ulcerated skin) –> Crusting
How would you describe the classic appearance of VZV on skin?
“Dewdrop on a rose petal” - classic appearance
In histopathology, VZV is described as:
Intraepithelial vesicles
What is the difference between shingles and chickenpox?
In shingles, there is intense itching, burning, or sharp pain called RADICULONEURITIS
> The symptoms may be worse than chickenpox even though it just happens in the regional area
What is the sensory ganglia morphology of shingles?
> Dense predominantly mononuclear infiltrate (definition of mononuclear: inflammation is from a lot of lymphocytes and some plasma cells)
> Herpetic intranuclear inclusions in neurons and supporting cells
Other manifestations of VZV include what?
> Interstitial pneumonia
> Encephalitis
> Transverse myelitis
> Necrotizing visceral lesions
