Feline Infectious Peritonitis Update

What kind of virus does FIP stem from?

Feline Enteric Coronavirus (FCoV)

What are the TWO largest contributors to FCoV transmission?

1. Fecal-oral

2. Fomites

What kind of environment makes FCoV transmission more likely?

Multi-cat environment

True or False: FCoV typically has no clinical signs to mild enteritis.

True!

FCoV stays in the ————-.

GI tract

Explain how FCoV has a cycle of infection.

Shedding -> short-term immunity -> Reinfection -> Shedding

What is the internal mutation theory?

Less virulent enteric FCoV converts to virulent FIP by viral modifications within INDIVIDUAL cat

In the internal mutation theory, cell trophism changes from —- to ——.

Enterocytes -> Monocytes/macrophages

True or False: FIP is directly contagious.

False! FIP is NOT directly contagious.

Enteric corona should stay in the —————. If lots of corona virus is elsewhere, it is probably —-.

GI tract

FIP

True or False: With FIP infection, there can be a full immune response resulting in a clinically healthy cat or a partial immune response, resulting in either wet or dry FIP.

True!

What are the TWO pathways that lead to the two different forms of clinical FIP from a partial immune response?

Inappropriate antibody -> Effusive (wet) FIP

Inappropriate CMI -> Non-effusive (dry) FIP

Pyogranulomatous inflammation and effusion is characteristic of the —- form of FIP, while vasculitis reflects the —— form.

Effusive/wet

Non-effusive/dry

True or False: FIP can begin as dry and progress to wet.

True!

True or False: There is typically no viremia in FIP infection.

True!

What are the THREE major risk factors for acquiring FIP?

1. Multi-cat environment (increased corona exposure)

2. Recent stressor

3. Typically young (<3 years)

Effusion in wet FIP is usually —-, but may be —-.

Abdominal

Thoracic

What are the THREE major locations dry FIP likes to live and create pyogranulomatous inflammation?

1. Abdominal/thoracic organs

2. Eyes

3. Neurological system

Is FIP more common in males or females?

Males

True or False: FIP diagnosis is founded upon history, signalment, clinical signs, clin path, imaging, and confirmatory testing.

True???? Lmao

What should you refer to that helps you "place bricks" in diagnosing FIP?

ABCD FIP Diagnostic Tool

You have a cat in which you suspect FIP. What are the first TWO things you should do?

1. PE

2. CBC/Chemistry

After you perform an exam and bloodwork, what is the next major step in an FIP workup?

Diagnostic imaging (absence/presence of effusion)

Is wet or dry FIP form more common?

Wet

Name at least FOUR analyses you can use on the effusion present in an FIP workup.

1. Cytology

2. Biochemistry

3. Rivalta's test

4. Molecular detection of FCoV (RT-PCR)

5. Detection of antibodies against FCoV (IF/ELISA)

What is Rivalta's Test? How is it used for wet FIP workup?

Vinegar and water mixed with the effusive fluid

If high protein -> gels together like a jellyfish. If it does not, can be used to rule OUT FIP

True or False: Rivalta's Test is used to confirm wet FIP.

False! Rivalta's test is used to rule OUT FIP, but a positive test does not confirm wet FIP.

What are the TWO major next steps in an FIP workup if there is an absence of effusion?

1. Biopsy (Histopath + molecular detection of FCoV)

2. Blood sample (IF/ELISA or RT-PCR)

What is considered the absolute diagnostic for dry FIP?

When is it discouraged?

Biopsy

Critical subjects

Why is blood sample not great for diagnosis of dry FIP?

Spillover from enteric CoV -> false positive

What are the THREE best FIP confirmatory tests?

1. PCR (effusions; sometimes tissues or blood)

2. Immunochemistry/direct immunofluorescence (effusion; FNA samples in saline)

3. IHC (biopsy)

PCR is best run on —- for confirmation of FIP.

Effusion

True or False: FIP should respond relatively quickly to several days of treatment.

True!

True or False: One future diagnostic option that could pop up and is being investigated now involves collecting urine and kidney samples for diagnosis of FIP.

True!

A cat has a Corona antibody positive at 1:800. Does that mean it has FIP?

No- it simply says there has been exposure or the cat has had enteric FCoV at one time.

True or False: One possible new treatment of FIP is a 3C-like protease inhibitor, like GC-376.

True!

What is the drug that is now approved as a treatment for FIP that once was a "black market" drug?

GS-441524

True or False: It is illegal for veterinarians to dispense or administer medications from unlicensed sources.

True!

True or False: Drugs compounded from bulk substances can be approved and are legal.

False! Drugs compounded from bulk substances are UNAPPROVED and NOT strictly legal.

True or False: FDA approved GS-441524 in the US solely to be prescribed by a vet for a SPECIFIC cat patient for the TREATMENT of FIP, and any other use of the drug is currently illegal.

True!

What is the pro-drug of GS-441524 that is an approved human drug that vets are now trying to prescribe in either its standard or compounded forms?

Remdesivir

True or False: The overall success rate of GS-441524 is quite high at 84.6%.

True!

Success of GS-441524 is lower with ———- and ————.

—————— may be associated with higher short-term mortality.

Neurologic forms

Wet FIP

Increased LDH

True or False: Combination of GS-441524 with other antivirals like GC-376, omega interferon, molnupiravir, and mefloquine might be helpful in treating FIP, but this is still uncertain.

True!

The dose of GS-441524 is ——————-, and you should increase the amount as the cat gains weight.

5-15 mg/kg SID

What GS-441524 dose should you use for severe disease, neurologic, or ophthalmic FIP forms?

20 mg/kg, may divide to BID

How long should GS-441524 be administered to an FIP cat?

12 weeks

True or False: At the end of GS-441524 treatment, normalization of clinical signs and lab results is expected. There can occasionally be a maintenance of a high globulin count, but this is rare.

True!

Overall, GS-441524 is well-tolerated.

What are the THREE side effects that may arise?

1. Uroliths

2. Injection site pain with injectable forms

3. Long FIP (hyperesthesia/lymphadenopathy)

What is the nucleoside analog that was initally developed by Soviet Union as part of a biological weapon research that is mutagenic and crosses the blood-brain-barrier?

Molnupiravir

True or False: Molnupiravir has similar efficacy to GS-441524/Remdesivir as a monotherapy.

True!

What is the dosage of Molnupiravir?

10-20 mg/kg BID (lower dose effusions without neuro/ocular signs)

What drug may be used as a rescue therapy for FIP?

Molnupiravir

Although molnupiravir is well-tolerated, what are THREE side effects that may arise?

1. Neutropenia

2. Increased hepatic enzymes

3. Folded ears

What are THREE FIP preventions that may be helpful?

1. Small group low stress housing

2. Hygiene

3. Fecal PCR screening

Is separating kittens from queens a good method of prevention for FIP?

No- not worth of social implications for the cat

Why is the current FIP vaccine not recommended?

Doesn't work well- might make FIP worse with potentiation of antibodies

Like what was the point of this lecture?

Idk dude