L7: FIP: Dx And Control (Levy) Flashcards
FIP can present like:
- liver dz
- lymphoma
- FIV
- CNS dz
- abd. Neoplasia
- toxoplasmosis
- bacterial peritonitis
Transmission of FCoV
- fecal-oronasal
- highly infectious
- shed in feces (also saliva, resp. Excretions, urine)
Prevalence of FCoV Ab in pet cats
25-75%
Prevalence of FCoV Ab in feral cats
12%
What percent of carriers of FCoV develop FIP
Less than 10%
What proportion of FCoV seropositive cats shed the virus? Seronegative?
Seropositive: One third
Seronegative: none
CS of FCoV
- asymptomatic or brief mild upper resp. Tract signs
- self-limiting diarrhea, vomiting
Etiology of FIP
- clinical IMMUNE-MEDIATED syndrome
- induced by infection with FCoV (may involve viral mutation)
- can be systemic or affect single organ
- pathogenicity enhanced by FeLV > FIV
Epi of FIP
- prevalence about 1%
- most common in young cats w/ hx of multi-cat env
- purebreds, males have higher risk
Dx of FIP
- PE/Hx
- CBC/Chem, serology, effusion analysis, CSF analysis, RT-PCR, virus culture, tissue biopsy
CS of FIP
- fever unresponsive to abx
- rapid wt. loss
- icterus and/or yellow plasma
- anorexia, depression
- body cavity effusions
- abd. Mass
- neuro signs
4 main types of FIP
Effusive
Noneffusive
Intestinal
Neurological
Effusive FIP char. By:
- vasculitis, serum exudation
- peritoneal, pleural, pericardial effusion
- abd masses (omental and visceral adhesions, granulomas, mesenteric lymphadenopathy)
Noneffusive FIP char. By:
- vague signs
- ocular inflammation (uveitis)
- neuro signs
- irregular kidneys
- mesenteric lymphadenopathy
- intestinal obstruction
Intestinal FIP char. By
-focal granulomatous lesion of colon or ileocecocolic junction
-death by 9 mo. Usually
-may mimic intestinal adenocarcinoma
+/- GI obstruction
Most common cause of inflammatory CNS dz in cats
Neurological FIP
CS of neurological FIP
- multifocal CNS signs
- hyperasthesia
- flaccid, mentally dull
What do you expect to find on CBC in cat with FIP?
- lymphopenia
- neutrophilia +/- mild L shift
- hyperproteinemia
- nonregen. Anemia
*may be normal!
What do you expect to find on Chemistry in cat with FIP?
- hyperglobulinemia w/ low A:G ratio
- hyperbilirubinemia
- inc. LIV enzymes
*may be normal!
Rivalta Test
- easy test for FIP
- H2O + acetic acid + effusion
- if congealed, positive for FIP
Ab titer levels in healthy cats do/do not correlate w/ FIP risk
Do NOT
No FIP serologic test; must test for FCoV
:)
FCoV serologic testing indications
- support dx of clinical FIP
- contact with FCoV shedder
- screening catteries
- screening before adding new cats to FCoV-free catery
- controlling FCoV in catteries
- not indicated for screening healthy pet cats or in shelters
Effusion analysis in FIP
-color clear to YELLOW
-viscous, frothy, may clot in cold
-protein >3.5 g/dL w/ low A:G ratio
-
CSF Analysis in FIP
- extremely high protein (>200)
- extremely high nucleated cells (>100), esp. NEUTS, lymphs, macs
- risk of herniation during CSF collection
RT-PCR testing for FCoV
- sensitive
- excellent for detecting FCoV shedding in feces
- does NOT distinguish cats at risk for FIP
- can be done on effusion or biopsy
Pathologic findings of FIP
- serosal surfaces covered in white plaques (fibrin)
- nodules on intestines, etc.
- omentum looks like scrambled eggs
- adhesions of omentum, mesentery
- lymphadenopathy
- focal lesions
Histologic findings of FIP
-pyogranulomatous, vasculitis
What is gold standard for diagnosing FIP
IHC for viral antigen + biopsy
A:G ratio usually low/high in cats with FIP
Low (high globulins)
TP usually low/high in FIP
High (globulins)
Most reliable confirmatory test for FIP
IHC
FIP vaccination
- efficacy is controversial
- IgG seroconversion DOES occur
- not a core vaccine
- only replicates in lower body temps of the nose
Heritability of FIP susceptibility
> 50%
-may have polygenetic inheritance
Seropositive cats in households from which other cats died of FIP had the same/different risk of developing FIP as cats from household without history of FIP
Same
(Siblings may be at higher risk)
HOWEVER, FCoV seroNEGATIVE kittens placed in catteries with endemic FIP suffered 90% mortality
Risk of testing positive for FCoV in animal shelters
-massive increase in amount of coronavirus shed within first week of being in shelter (stress to blame for increase in shedding and transmission)
Epizootic of FIP in catteries
- uncommon
- may last 6-12 months
- causes high losses in kittens and juveniles
- may return to enzootic form
- due to new virus strain introduction
Enzootic of FIP in catteries
- most common pattern (low grade, chronic)
- sporadic, infrequent, unpredictable losses
- overall 1-5% mortality
Tx of FIP
- no tx for healthy seropositive cats
- supportive tx for coronaviral enteritis (self-limiting)
- palliative tx of FIP (predinosolone, anti-inflammatories, supportive care)
Antiviral and immunomodulating drugs for FIP
- none available right now
- UC davis has clinical trial w/ protease inhibitor drug used against SARS and MERS in people
Why is it hard to misdiagnose FIP?
- nonspecific CS
- widespread seropositivity of FCoV Ab
- no discriminating tests for FIP
Diagnostic Algorithm for FIP
See slide 38 (or pic)
