SA Viral (NAVDF 2023) Flashcards
FIV: DNA or RNA virus?
RNA
Retrovirus
FeLV: DNA or RNA virus?
RNA
Retrovirus
FIP: DNA or RNA virus?
RNA
Coronavirus
Canine Distemper: DNA or RNA virus?
RNA
Paramyxovirus
Feline Calicivirus: DNA or RNA virus?
RNA
Calicivirus
Feline Poxvirus (Cowpox): DNA or RNA virus?
DNA
Poxvirus
Orf: DNA or RNA virus?
DNA
Poxvirus
Feline rhinotracheitis: DNA or RNA virus?
DNA
Herpes virus
Papillomavirus: DNA or RNA virus?
DNA
Papillomavirus
Virus associated with Bowens in situ SCC
FcaPV-2 (3, 4 less common)
FeLV
(+/- FIV)
Virus that causes cutaneous horns on feline pads, eyelids
FeLV
FIV transmission
Bite wounds
(vertical transmission is rare)
IHC stain for FeLV
gp70
Dermatologic lesions associated with FIP
Erythema, ulcers on head and neck. Vasculitis
(Uveitis, respiratory disease, peritonitis)
Histopathology of cutaneous findings from FIP
Vasculitis
Viral Ag in blood vessel walls
T or F: Canine Distemper virus is reportable
TRUE
Dermatologic sign of canine distemper virus
Hard pad disease
*Nasodigital hyperkeratosis
*Impetigo in young puppies
Histopath of canine distemper virus
Orthokeratotic + parakeratotic hyperkeratosis
Cytoplasmic inclusion bodies (rare nuclear inclusions)
IHC shows virus in haired skin, foot pads
Clinical signs of feline calicivirus
*Vesicles in mouth, nasal –>ulcers
*Sneezing, conjunctivitis
*Transient feline limping syndrome (resolves in a few days)
*Hemorrhagic/virulent form: 30-50% mortality 2’ sepsis. More common in adults
Diagnosis of feline calicivirus + histopath findings
PCR test: swab oropharynx or conjunctiva
Histopath: epidermal necrosis, ballooning degeneration of KCs, vasculitis
Which species can develop Cowpox?
Cats!
ZOONOTIC- reportable. Fatal to immunocompromised humans
Transmission of feline poxvirus
Direct (wounds from rodents) fomites
Reservoir for feline poxvirus
Rodents
Seasonality of feline poxvirus
More common in summer, fall when there is a higher rodent population
Cutaneous lesions of feline poxvirus
Pocks = crater-like skin lesions
“Necro-ulcerative dermatitis”
Primary: Ulcerated nodule on head, neck, forelimb
Secondary lesion (nodules ulcerate and develop into): craters with crust
(possible oral vesicles, 20%)
Prognosis of feline poxvirus in exotic felids
Fatal pneumonia
Treatment for feline poxvirus
None. AVOID GLUCOCORTICOIDS
Clean with disinfectants, bleach
Scarring permanent, Lesions heal over 4-5w
Which small animal species have reported orf
Dogs (rare), 1 cat
Pack of hounds that fed on sheep carcasses
Main species = ovine, caprine
T or F: Most cats that recover from feline herpesvirus become carriers
True. 80% shed intermittently lifelong
Where does the herpesvirus live in the cat (nerve)?
Trigeminal ganglion
Cutaneous signs of feline herpes virus
Ulcers on nasal planum, bridge of nose, periocular, trunk, footpads
Are adult or kittens more often affected by feline herpesvirus dermatitis
Adults
Predominant cell type on cytology of FHV1
Eosinophils (+ neutrophils)
T or F: PCR of FHV1 in skin sample has 100% sensitivity for feline herpesviral dermatitis
True. 95% specificity
What is the unique feature of FHV1 on histopath
Necrosis of sweat glands
Prominent eosinophils
Treatment for FHV1
1) Avoid glucocorticoids, reduce stress
2) Famciclovir (120mg PO BID)
3) Topical imiquimod 2-3d/w
4) No benefit from oral lysine
5) Interferon: human INF-alpha or feline INF-omega
Which CPV is associated with ORAL papillomatosis
CPV1
Which CPV is associated with cutaneous papillomatosis
CPV 1, 2, 6, 7
- Exophytic cutaneous papillomas
- Cutaneous inverted papillomas
- Venereal papillomas
- Multiple papillomas of the footpad
Which CPV is associated with pigmented viral plaques
CPV 3-16 EXCEPT 6, 7, 13
Which cell layer initially becomes infected with CPV
Basal cells (from contact with mucosa or injury to skin)
Where in epidermis are E6 and E7 of CPV produced
Basal/deep layers
E6 and E7 amplify viral genome
Where in epidermis are L1 and L2 of CPV expressed
Closer to epidermal surface
Capsid proteins, viral assembly
What happens once CPV-infected KC is sloughed
KC lyses, and viral particles are released to their neighbors
T or F: IgG against CPV can help prevent future CPV infections
True. IgG blocks CPV entry into basal cells
T or F: IgG against CPV can resolve a current infection
False
CELL MEDIATED IMMUNITY RESOLVES INFECTION
What type of immunity is needed to clear CPV: humoral or cell-mediated
Cell mediated
What happens to CPV in each layer of the epidermis
Basale: CPV infects basal cells
Stratum spinosum, stratum granulosum: CPV replicates. Large keratohyalin granules in SG
Stratum corneum: New virus released from here. Koilocytes
Which tumor suppressor gene does E6 affect
p53
Which tumor suppressor gene does E7 affect
pRb
Treatment for oral papillomatosis
Azithromycin?
Cryotherapy, crushing, laser – stimulate immune response
IFN oral
Imiquimod
Autologous/recombinant vaccine
Most common age for oral papillomatosis? For Exophytic cutaneous papillomatosis?
Oral: Young
Exophytic cutaneous: Older
Breed, sex predilection for Exophytic cutaneous papillomatosis
Breed: Kerry blue terrier, cocker spaniel
Male > Female
How long does it take for Exophytic cutaneous papillomatosis to regress spontaneously
6-12 months, unless immunosuppressed
Age, breed predispositon for inverted cutaneous papilloma
<3 yr old
Beagle, Bernese mountain dog, cocker spaniel, great dane, Irish setter, Kerry blue terrier, whippets
Clinical lesion, body location of inverted cutaneous papilloma
Cup-shape with pore opening
Ventral abdomen
T or F: Pedal papillomas often spontaneously regress
FALSE.
Tx: Keratolytic products vs surgery
Young dogs
Breeds predisposed to Canine pigmented viral plaques
Pug, Mini schnauzer
Boston terrier, Frenchie
Body location of Canine pigmented viral plaques
Ventral abdomen, thorax, medial thighs
RARE SCC TRANSFORMATION
T or F: Pigmented viral plaques could transform to SCC
TRUE
IHC markers for Papillomavirus
L1 protein (active replication)
p16 marker (inactive replication)
Histopath cell classic for CPV
Koilocytes in Stratum spinosum
Location of inclusion bodies (intranuclear, intracytoplasmic) of CPV, FHV
Intranuclear
Cause of Feline Sarcoid
BPV-14
Other name for Feline sarcoid
Feline cutaneous fibropapilloma
Signalment of Feline Sarcoid patient
Young cat, <5 yr
Cattle exposure
Male
Body site for Feline Sarcoid
Nodular masses on head, neck, digits
Histopath for feline sarcoid
Picket fence-like appearance of fibroblastic cells
over hyperplastic epidermis
Most COMMON causative agent of feline viral plaques
FcaPV-2
(also FcaPV 3, 4)
Age of cats with viral plaques
Older age
Underlying immunosuppression (FIV/FeLV/ GC therapy)
Body lesion with feline viral plaques
face
Concurrent infection that can occur with feline viral plaques
Demodex
Concern with unmanaged feline viral plaques
Transformation to BISC
What is the major causative agent for BISC
FcaPV-2 (33%+)
Long lasting dysplasia leads to neoplasia
Also many are FIV/FeLV+
Treatment for feline BISC
Laser, IFN-alpha, strontium 90 plesiotherapy
Famciclovir MOA
Inhibits DNA polymerase
Imiquimod MOA
Immunostimulant
Binds TLR7; induces NFkB + proinflammatory cytokines
What is the etiology of nasal SCC in cats if positive for p16? Prognosis?
Viral etiology if + for p16; longer survival than p16 negative!
Associated with FcaPV2
What virus causes Giant Cell Dermatosis
FeLV (+gp70)
*Multinucleated keratinocytes
*Head/neck alopecia, pruritus, ulcers
*Progressive, die quickly
Feline oral papilloma virus
FcaPV 1, 2
Feline exophytic papilloma virus
FcaPV1