Feline Infectious Diseases 2 (Garden) Flashcards
Causative agent of FIP?
Mutated Feline Coronavirus
= infection is common but clinical disease uncommon
Which type of cats does FIP affect and is it serious?
Domestic and non-domestic, FATAL
ALternative names for feline coronavirus?
used to be further classified into
- feline enteric coronavirus (FECV)
- FIPvirus (FIPV)
but now thought to be biotypes of same virus
What type of virus causes FIP?
- enveloped ssRNA virus
- large
- easily undergoes mutation
- two types (1 entirely feline [most common], 2 recombinant with canine coronavirus)
How does the feline coronavirus replicate?
- in cytoplasm
- newly synthed virions steal envelope from membrane of ER and Golgi
- released by cell lysis or vesicle fusion ith plasma memb
Is feline coronovirus stable outside the host?
NO relatively unstable
- inactivated at room temperature in 24hrs
- 56* in 1h
> unless protected from heat, light and chemicals then can survive weeks
Is FECV common? How is it transmitted and what are the clinical signs?
- yes present in large population of healthy cats
- oronasal transmission
- clinical signs mild/inapparent (VD+ and URT signs)
Where does FECV replicate?
Enterocytes
What is FIPV?
FCoV can mutate -> FIPV
- infects macrophages causing systemic infection
- “FIP” = clinical disease syndrome resulting from ineffective immune response
4 potential outcomes following FCoV infection?
- Transient infection majority
- Persistnet infection some
- FIP minority
- Resistance to FCoV infection VERY FEW
Outline pathophysiology of FIP
- immune complexes -> vasculitis, complement activation and excessive cytokine production
- viral Ag + Antiviral Ab + Complement -> complement fixation -> release of vasoactive amines -> Endothelial cell retration and ^ vascular permeability -> protein rich exudate
- neutrophils release lusosomal enzymes -?> vessel wall necrosis
What type of immune response is needed to clear a FIP infection?
- strong CELL mediated response will be protective
- partial cell mediated -> Non-effusive dry dz
- poor cell mediated -> Effusive wet dz
What are the clinical signs assoc with FIP?
(d/t vasculitis and 2* organ damage, incubation period weeks to months with onset being acute or insidious)
> early signs non-specific
- pyrexia
- innappetance/anorexia, wt loss
- D+
- listlesness
- dehydration
- icterus
> effusive v non-effusive form (some cats mixed)
- majority effusive (Ascites, pleural effusion and dyspnoea, pericardial effusion)
- dry/ granulomatous (pdf eyes, brain and CNS, kidney, liver, localised regions of intestine)
How can FIP be dx? Changes on CBC, biochem and peritoneal tap?
- difficult antimortem (esp dry)
- hx, cs, PE (always include occular fundic exam- uveitis? chorioretinitis?)
> CBC - lymphopaenia
- neutrophilia and LS
- mild non-regenerative anaemia
- may be normal!!
> biochem - hyperglobulinaemia (polyclonal gamma globulin spike, ^ APP, alb:glob ratio peritoneal tap
- looks normal
- high protein content (may clot in tube and froth when shaken, >35g/l, at least 50% globulin)
- cellularity variable (may be
Other than standard diagnostics, what dxx can be performed to find coronavirus? How efective are these?
> IFA and ELISA
- IFA test for anti-FCoV ab titre (FIP virus-infected feilne cell line substrate)
- these do NOT distingush FCoV and FIPV so + result not indicative of FIP. Sometimes - result with FIP d/t problems with testing
CSF
- dry tap or ^ protein/cells
Direct FA and IHC on tissue
q-PCR detects genomic RNA (but can be + in healthy cats)
- New q-PCR for replicating DNA more precise but values not known
a1 acid glycoprotein
- APP from liver, not specific for FIP but can be used alongside other findings
