Dr Soma’s probability of wet FIP table 3 workbook and FIP... · In the first edition of my book for cat guardians, Feline Infectious Peritonitis and Coronavirus, I made the statement

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Feline Infectious Disease Masterclass

Dr Diane D. Addie

__________________’s workbook

page

SATURDAY

Diagnosis of effusive FIP using an algorithm lecture 2

Dr Soma’s probability of wet FIP table 3

Case history: Mirabelle 4

Case history: Jess 8

Workshop 1: effusive FIP diagnosis

11

Case history: did this cat get FIP when you spayed her? 11

Case history: does Lisa have FIP? 12

Case history: does Oliver have FIP? 17

SUNDAY

Non-effusive FIP lecture 18

Workshop 2: non-effusive FIP diagnosis

Case history: does Zena have FIP? 23

Case history: does Buffy have FIP? 24

Case history: does Tommy have FIP? 25

Case history: does Basil have FIP? 29

Recommended laboratories and contacts 30

References 30

APPENDICES AND SPARE WORKSHEETS

Catvirus.com FIP diagnosis worksheet template 33

FIP diagnostic flowchart Step 1 for the cat’s guardian to complete 34

Treatment protocol for effusive FIP 35

Treatment protocol for non-effusive FIP 36

Effusive FIP diagnosis algorithm 37

Non-effusive FIP diagnosis flowchart 38

FCoV GIT diagnosis flowchart 39

Spare flowcharts for use in the workshop 40

Diane D. Addie GIEFEL October 2016

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Diagnosing effusive FIP using an algorithm

“A wrong diagnosis can be far more devastating than no diagnosis.” Dr Mike

Willard

“More cats have died of FIP tests than have died of the disease.” Dr Niels Pedersen

In most cases, FIP is fatal. An erroneous diagnosis of FIP can be tragically fatal: if an

inappropriate therapy is given or if guardians opt to euthanase their pet to avoid

suffering, thus the life of the pet is unnecessarily wasted.

In the first edition of my book for cat guardians, Feline Infectious Peritonitis and

Coronavirus, I made the statement that 80% of cats diagnosed with FIP turn out to

have some other – often treatable – disease. My statement was based on having had a

summer student telephone veterinary surgeons who had submitted samples to our

diagnostic laboratory at the University of Glasgow Veterinary School, backed up by

my personal experience of getting to the correct diagnosis in cases submitted to me

for second opinion. Various recent publications have enabled me to refine my 80%

figure considerably. While 80% remains true for non-effusive FIP, recent research

has shown that the probability that a cat really has effusive (wet) FIP varies with the

cat’s age and breed.

The probability that an effusion IS caused by FIP varies with the age and breed

of the cat: between 5% and 89% of cats with effusions suffer from some other

condition

Effusive FIP is much more easy to diagnose than non-effusive FIP. The legendary

Italian veterinary pathologist, Dr Saverio Paltrinieri, published a paper in which 79 of

110 cats with effusions (72%) were diagnosed as having wet FIP, in the other 31 cats,

the effusions were due to diseases other than FIP. Thus a correct diagnosis was more

likely to be obtained in effusive FIP compared with only around 20% (or less Jeffery et al,

2012) correct diagnoses of non-effusive FIP.

Recent research indicates that a positive FCoV RT-PCR test on an effusion is 100%

diagnostic of FIP. Doenges et al; Felten et al; Longstaff et al.

In 2013, Dr Soma and his colleagues

published results of FCoV RT-PCR tests on an enormous number of effusions sent to

his laboratory in Japan: these results showed that the percentage of effusions positive

by FCoV RT-PCR varied with the cat’s breed and age, see table 1. which I have

adapted from the graph published in Dr Soma’s paper. Up to the age of 4-5 years,

purebred cats were more likely to be positive than domestic cats, and after 6 years of

age the converse became true (possibly because the domestic cats have experienced

exposure to FCoV in a rescue or boarding cattery). The percentage of effusions

positive for FCoV decreased with the age of the cat: from 95% of 139 effusions from

pedigree cats up to one year old, to only 11 % of effusions from pedigree cats of 10

years of age or older.


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Table 1. Likelihood of effusive FIP according to age and breed Soma et al

Age (yrs) Pedigree cat Domestic cat

<1 95 79

1 70 42

2-3 53 41

4-5 60 33

6-7 20 21

8-9 23 34

≥ 10 11 14

In this table, the likelihood of a cat with an effusion having FIP is given: for

example, a pedigree cat under a year of age is 95% likely to have FIP, whereas a

domestic cat aged 6-7 years of age is only 21% likely to have FIP. From this

table, you can work out the probability of effusive FIP according to a cat’s age

and breed.

Obviously this table is NOT a substitute for sending a sample of effusion to a

reputable veterinary laboratory for a FCoV RT-PCR test.

If you want to, you can read a full blog I wrote on this subject at:

https://steemit.com/cats/@catvirus/diagnosing-feline-infectious-peritonitis-fip-diane-d-addie

If you do read it please give it an upvote!

Most cats infected with FCoV do not develop FIP

https://steemit.com/cats/@catvirus/diagnosing-feline-infectious-peritonitis-fip-diane-d-addie


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The cause of FIP is infection with feline coronavirus (FCoV). However, most FCoV

infections do not have any serious consequences: the majority of infected cats have

subclinical infection, or a bout of diarrhoea. A small percentage of cats mounts a

deleterious immune response to FCoV: clinical signs form a spectrum from very acute

severe infection with destruction of many blood vessels and leakage of plasma into

body cavities – this is known as effusive, or wet, FIP – and death within days to

weeks, to chronic or non-effusive FIP, which can last for months. (See my YouTube

animation https://youtu.be/6RyI2LI9R9Q ). In dry or non-effusive FIP the progress is

slower, the number of blood vessels damaged is fewer, and a chronic immune

response is a pyogranuloma formation as the body attempts to wall off the infection.

Non-effusive FIP is much more difficult to diagnose than effusive FIP.

The effusive FIP diagnosis algorithm, the step one questionnaire and

worksheet templates are in the Appendices. The FCoV awareness /

pedigree kitten poster is in a separate document. All are available for

download from www.catvirus.com

CASE HISTORY 1: MIRABELLE

Cat’s name ....... Mirabelle ............................................................... .............. ..............

Breed ......................................... Age..................Sex..........F............................... ….....

Other cats? .......................... Indoor/Outdoor .................................................... .............

How could this cat have gotten FCoV infection? ............................................... ...........

............................................................................................................................ ...........

How long ago might the cat have become infected? ......................................... .............

(if it was more than 18 months, this is unlikely to be FIP)

Recent stress? .................................................................................................. ..............

Clinical signs ...................................................................................................... ...........

..........................................................................................................................................

..........................................................................................................................................

Key message: Feline infectious peritonitis (FIP) is a disease predominantly

affecting young pedigree (purebred) kittens and cats.

However, any age of cat can be affected.

https://youtu.be/6RyI2LI9R9Q


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Step 1. Question 1. Where/how could your cat have caught FCoV? FIP can only develop in a cat who has been infected with feline coronavirus (FCoV) –

it cannot occur out of the blue. Go through the following questions to try to establish

whether or not your cat has had the chance to become infected.

Score through or circle the Yes or No

My cat is pedigree (purebred) Yes / No

I have more than 6 cats and they use litter trays Yes / No

My cat came from a rescue shelter Yes / No

My cat has been in a boarding cattery Yes / No

We recently obtained a new cat or kitten Yes / No

My cat has been to a cat show in the last year Yes / No

My cat has visited a stud cat in the last year Yes / No

A queen visited my stud cat in the last year Yes / No

If the answer is Yes to any of the questions above, then your cat has possibly had the

opportunity to become infected with FCoV. If you answered No to all of the

questions above, then FIP seems unlikely, but is not completely ruled out.

Step 1. Question 2. Has the cat experienced a stress in the last 18 months?

We only got the cat within the last year Yes / No

My cat has or had another illness recently Yes / No


We recently got a dog or puppy Yes / No

We recently had a baby or adopted a child Yes / No

We have 6 or more cats Yes / No

We have moved house in the last year Yes / No

We put the cat into a boarding cattery Yes / No

Somebody the cat loves has been away, or ill, or died Yes / No

The cat recently gave birth Yes / No

We took our cat to a cat show Yes / No

The cat was hospitalised at the veterinary surgery Yes / No

The cat has been on some other kind of journey Yes / No

The cat has been exposed to some other stress not listed here Yes / No

If the answer is yes to any of the questions above, then your cat has likely experienced

stress. If you answered No to all of the questions, try to think if your cat has

experienced a stress which I have not listed. If you answered no to all the questions in

step 1, FIP seems very unlikely: take your answers and the algorithm to your

veterinary surgeon and discuss the situation with him or her.

Differential diagnosis What can I do to differentiate from FIP?

Conclusion: I believe/do not believe this cat has FIP because ........ ..............................

..........................................................................................................................................


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Treatment / next diagnostic action ..................................................................................

..........................................................................................................................................

Step 2: Effusive (“wet”) FIP - clinical signs

Key message for step 2, clinical signs:

CATS WITH FIP HAVE SOME ABNORMAL CLINICAL SIGNS

Cats with FIP are not simply fat or pregnant! In effusive FIP, there is an effusion!

Effusive FIP is the more acute condition than dry FIP: usually occurring within days

to weeks of FCoV infection and/or a stressful event in the cat’s life. FIP is an

immune-mediated vasculitis: in effusive FIP, many blood vessels are affected,

allowing fluid to leak out into the abdomen, thorax or pericardium. Thus the cat

presents with ascites or pleural and occasionally pericardial effusion. The ascitic cat

may appear to have put on weight, although ribs are usually more palpable. The cat

may still be bright and eating, though some are dull and anorexic. The temperature of

cats with FIP rarely exceeds 103oF (39

oC). A cat with a pleural effusion will present

with dyspnoea. Cats with a pericardial effusion will have muffled heart sounds.

The single most useful thing you can do next is to analyse the effusion.

Step 3: Effusive (“wet”) FIP - analysis of effusion

Drawing off the effusion is useful for 3 reasons:

it relieves some of the clinical signs for the cat, removing not just physical

fluid, but also virus and sources of inflammatory cytokines

it enables a far more accurate diagnosis than a blood sample

it allows you to place a needle for administering interferon omega or other

treatment directly to the site of the lesions

Paracentesis can often be performed in the conscious cat using only clipnosis

(applying clothes pegs or paper clips to the scruff of the neck). Pozza et al

Look at the effusion and smell it – if it stinks, you are dealing with a

bacterial infection, NOT FIP

FIP effusions vary in appearance: most are clear and straw-coloured and froth when

shaken (because of the high protein content). Some may be blood-tinged, or even

lipaemic, but cloudy, turbid, stinking purulent effusions point to a bacterial infection,

not FIP.

A negative Rivalta test is 93% NOT likely to be effusive FIP The Rivalta test is one of the simplest and most economic ways to rule out FIP (the

test has a high negative predictive value (NPV) of 93.4% for FIP), costing pennies to

perform and taking only a couple of minutes. To perform a Rivalta test, one drop of

8% acetic acid (ordinary clear/white vinegar) is added to 5 – 10 mls of still water

(which must be at room temperature) in a clear test tube and mixed thoroughly. A


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drop of effusion is carefully layered on top. If the effusion dissipates like a wisp of

smoke in air the Rivalta test is negative and the cat is 93% not likely to have FIP.Fischer

et al, 2012 If, however, the effusion hangs from the surface in a globule, then slowly

floats down like a jellyfish, the Rivalta test is positive. A positive Rivalta test means

that the cat is 58.4% likely to have FIP (i.e. only about 6 of 10 cats with a positive

Rivalta test do have FIP, the other 4 cats have some other condition). Positive

Rivalta’s test results may also be obtained in cats with bacterial peritonitis or

lymphoma. However it is usually easy to differentiate these effusions by macroscopic

examination, cytology and/or bacterial culture.

You can watch a video of positive and negative Rivalta tests on my YouTube channel

http://www.youtube.com/watch?v=XmOk2veunqA ; however please be aware that the video

was made before a more recent publication by Fischer et al,2012

and that in the film I

give percentages from a previous publication by Hartmann et al, 2003

of PPV of 86%

and NPV of 97% which were over optimistic. One problem with the Rivalta test is

that it is quite subjective: a blinded study showed that two independent investigators

gave quite different interpretations. Fischer et al, 2012

In addition, around 10% of Rivalta

tests cannot be conclusively designated as either positive or negative. Fischer et al, 2012

I

found that I needed to practise with quite a few effusions, and that the water that I

used considerably altered the results, curiously my own tap water (which is from a

mountain spring) gave better results than distilled water. Use water at room

temperature or even slightly warmed rather than from a fridge (cold water causes false

negative reactions). The test can work with old effusion samples which have been

stored in a fridge for some days but can give false negative results if the effusion has

been frozen.

Total protein in the effusion and albumin:globulin ratio (A:G)

The total protein concentration in the effusion of a cat with FIP is usually greater than

35 g/l and this usually consists of more globulin than albumin, pushing down the

albumin to globulin (A:G) ratio. The A:G of an effusion is one of the most useful tests

to perform in practice for a quick indicator of whether or not a cat may have FIP and

can be easily performed on an in-house biochemistry analyser machine. To calculate

the A:G ratio, divide the albumin by the globulin values. An A:G of < 0.4 indicates

FIP is quite likely; an A:G of >0.8 rules out FIP; A:G of between 0.4-0.8 is

inconclusive so consider other parameters.

At this stage, you will be able to rule out effusions due to cardiomyopathy which is a

major differential in the young cat: such effusions are transudates, and usually have

only a few grams of protein per litre, although when an effusion has been present for a

long time, it begins to irritate the serosae and can become an exudate.

Cytology

In effusive FIP, there are generally fewer than 3 x 10 9 nucleated cells per litre in the

effusion (i.e. the effusion is a modified transudate, although around 10% of FIP

effusions are more cellular). In FIP, the cells are predominantly neutrophils and

macrophages. In bacterial peritonitis and pleurisy, the white blood cell count in the

effusion is much higher and the cytologist will usually see bacteria (if bacteria are

intracellular, this indicates that they were not simply contamination of the sample).

http://www.youtube.com/watch?v=XmOk2veunqA


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Cytology of pleural effusions is useful for differentiation of thymic lymphosarcomas,

since the predominant cell is the lymphocyte and they often appear malignant: in FIP

effusions lymphocytes are uncommon.

CASE HISTORY: JESS

Cat’s name ............ Jess ............................................................. ........................... .......

Breed .............DSH..................... Age......12 years........Sex........Female neutered........

Other cats? ........No.................. Indoor/Outdoor ......................... ...........................

How could this cat have gotten FCoV infection? ……… ...............................................

..........................................................................................................................................

..........................................................................................................................................

Clinical signs ..................................................................................................................

..........................................................................................................................................

..........................................................................................................................................

How long ago might the cat have become infected? ......................................... ............


Recent stress? .................................................................................................. ..............

Test Blood Effusion Unknown/

Other

Comment on significance

Albumin 26

Globulin 22

Alb:glob

Bilirubin

AGP

FCoV

antibody titre

FCoV RT-

PCR

Hct

Lymphocytes 0.43 x 10 9/l 72% of the wbc in the

effusion were lymphocytes

Cytology NA

Other

NA = not applicable


Conclusion: I believe/do not believe this cat has FIP because . ………………….........

..........................................................................................................................................

..........................................................................................................................................


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..........................................................................................................................................


..........................................................................................................................................

..........................................................................................................................................

FCoV antibody test

The presence of antibodies indicates only that the cat has been infected with

FCoV, the cause of FIP, not that the cat has FIP: bear in mind that the cat may be

sick with some non-FIP disease and co-incidentally infected with FCoV. Most cats

with FIP have extremely high antibody titres, but any FCoV antibody titre can occur

in cases of effusive FIP. Antibody titres of 0 are unusual in FIP cases and are usually

considered as indicating that the cat does not have FIP. (However, see below.)

An independent comparison of FCoV antibody tests showed that the best test was the

FCoV Immunocomb (Biogal, Israel). Addie et al, 2015

This test is ideal for the larger

veterinary hospital with its own small laboratory, the test kit comes complete and is

stored in the fridge. However, it does take around 45 minutes to perform. The best

rapid immunomigration (RIM) test was the F-Corona from Virbac. However,

sensitivity was a problem with some other commercially-available tests. False

positive results were rarer than false negative results and only came from some

laboratories using TGEV for immunofluorescence.

Don’t use effusions on RIM tests: doing so can give in false negative results

The Speed F-Corona (Virbac, France) and FASTest FIP (MegaCor, Austria) were the

best rapid immunomigration (RIM) tests for FCoV antibodies. Addie et al, 2015

Sensitivity

of RIM tests was sometimes adversely affected by using them with an effusion: we

showed that increasing amounts of virus in an effusion caused a decrease in antibody

signal, presumably by binding of the antibody in the sample with virus in the sample,

making it unavailable to bind with viral antigens in the test, causing a false negative

result. Meli et al

In such cats, where FIP is strongly suspected on clinical grounds,

despite negative FCoV serology, FIP can be confirmed by FCoV RNA detection (RT-

PCR), performed on a sample of the effusion (see step 4).

Step 4: Effusive (“wet”) FIP – sending the effusion to a veterinary

laboratory

Key message: a positive FCoV antibody test does NOT mean that a cat has FIP:

only that he or she has been exposed to FCoV infection

Key message: a positive FCoV RT-PCR test on an effusion is diagnostic of FIP.

However, a negative result does not rule out FIP: it depends on the sensitivity of the

RT-PCR test


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Since the advent of reverse-transcriptase polymerase chain reaction (RT-PCR) testing

becoming commercially available in many countries, diagnosis of effusive FIP has

become relatively straightforward: have FCoV RT-PCR tested on the effusion!

Unless the test has poor specificity (e.g. the primers for RT-PCR for a FCoV

messenger RNA RT-PCR Simons et al, 2005

also recognised some human DNA) then a

positive result will be confirmation that the cat has effusive FIP, Doenges et al; Felten et al;

Longstaff et al especially if a quantitative RT-PCR was used and a large amount of virus

detected. However, at time of writing, no paper has been published comparing the

sensitivities of the various different commercially available FCoV RT-PCR tests: thus

a negative test may not be able to rule out FIP. Since FCoV is an RNA virus, it is

highly subject to mutations, which mean that designing primers and probes for RT-

PCRs can be challenging: a conserved region of the genome should be chosen.

Veterinary surgeons should find out which RT-PCR their reference laboratory uses

and try to choose a test which has been published in peer-reviewed literature: a list of

laboratory tests this author trusts is given towards the end of these notes.

Sending an effusion to a veterinary laboratory for FCoV RT-PCR

Only a small amount of effusion is required for RT-PCR testing: 1ml in a plain tube

will certainly give enough for a laboratory to come up with a result. Although FCoV

is an RNA virus, and RNA is quite fragile, in fact when it is within a biological

sample, such as an effusion, or faeces, it is remarkably robust, and can be sent in

ordinary mail, without ice, without loss of a signal, for up to 3 weeks.

If using the University of Glasgow Veterinary Diagnostic Services laboratory it is

worth taking advantage of the amazing cytologists who also work there, and who can

often give you a diagnosis for samples which are negative, so include an air dried

smear of the effusion, and some effusion in an EDTA tube.


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EFFUSIVE FIP WORKSHOP

CASE HISTORY: DID THIS CAT CATCH FIP IN YOUR SURGERY?

You spay a young pedigree cat and when she comes back for her stitches out, you

notice that her abdomen is enlarged and feels fluidic.

1. Has she caught FIP while in your veterinary surgery????

2. List your explanations of what may have happened.

3. What steps are you now going to take to establish a diagnosis?

4. What steps will you take to ensure that this does not occur again?


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CASE HISTORY: DOES LISA HAVE FIP?

Steps 1 & 2: history and clinical signs

An email from Lisa’s guardian said this:

“Our nearly 5 year old Lisa (Russian Blue), the youngest

of our 4 cats, got diagnosed with wet FIP 2 weeks ago, on

Monday, 18 July 2016. She was in a very bad shape,

breathing heavily, but she improved the next day after

about 130ml fluid has been drained out from her chest.

She was put on antibiotics (Novoclad) straight away and

kept improving. A week later we started giving her

Prednisolone (1 a day) in addition to the antibiotics.

Yesterday, exactly two weeks later our vet was surprised

to see her going that well as usually the wet FIP cases die

in within a few days after diagnosis.

Lisa has been eating well all the time even when she was

very sick but now she has been playful again and alert and

appears to be her

normal self again. She has been breathing a bit faster than our other cats but this

could be due to the remaining fluid that her body is fighting to get rid of, the fluid was

not drained out completely. She sleeps on her side and seems pretty relaxed.

Our vet said the type of fluid pretty much indicates FIP. The Rivalta Test was

positive. The PCR test was not done as we thought we might not have 2 weeks left to

wait for the test result. Also, being told the test would give us only a 75% probability

we decided to start with the antibiotics instead and see how we go.”

Question 1. Has this cat had the opportunity to become infected with FCoV?

Answer …………………………………………………………………………………

Question 2: What is there in the HISTORY part of Rosana’s email which would rule

out, or rule in, a diagnosis of FIP?

Answer ………………………………………………………………………………..

…………………………………………………………………………………………

…………………………………………………………………………………………

Question 3: What is there in the CLINICAL SIGNS part of Rosana’s email which

would rule out, or rule in, a diagnosis of FIP?

Answer

…………………………………………………………………………………………..

………………………………………………………………………………………….

………………………………………………………………………………………….


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Step 3: In-house effusion results - we don’t have any, but the following results

were obtained from VetPath Laboratory

Step 4: External Laboratory Results

Vet Path Lab Services: CYTOLOGY: PLEURAL FLUID The sample consisted of 2mL of pale yellow, slightly cloudy, slightly viscous fluid. Cell count: 7.52 x 10^9/L Protein: 48 g/L SG: 1.032 Rivalta: positive Cytological preparations show a moderately cellular and fairly well preserved preparation on a stippled, eosinophilic, proteinaceous background which contains small numbers of erythrocytes. Nucleated cells consist predominantly of non-degenerate neutrophils. There are lesser numbers of large macrophages and occasional small lymphocytes. The macrophages occasionally demonstrate recent erythrophagia, and there is also phagocytosis of degenerate cellular/nuclear material. No overtly malignant cells or infectious agents are identified. Cytological preparations from the right thoracic fluid are very similar, although a slightly greater percentage of macrophages is present. Protein concentrations, and nucleated cell count are similar to those encountered for the left thorax. Neutrophils: 88 % Lymphocytes: 2 % Macrophages: 10 % Eosinophils: 0 % Gram Stain: no bacteria seen INTERPRETATION: Exudate COMMENT: This fluid is classified as an exudate, and the positive Rivalta test indicates an underlying inflammatory aetiology. The cell count is lower than would typically be associated with pyothorax, however, an atypical bacterial infection such as Mycobacteria may be associated with a relatively low cell count. Other considerations include FIP, and an underlying necrotic/ischaemic process as may be encountered with neoplastic disease, or a diaphragmatic hernia.

FCoV antibody titre: 1:2560

Toxo IgG 1:256

Toxoplasma IgM: < 1:16

FIV: Negative University of Sydney report on examination of the pleural fluid: Direct Immunofluorescence Report

Several cell preparations (cytospins) were made from the fluid submitted. A protein level of 55 g/L was measured on the fluid. Using a fluorescin labelled antibody against Feline Coronavirus (types I and II), immunofluorescence was performed to identify the presence of the virus within macrophages seen in the fluid. This was NEGATIVE for feline coronavirus infected macrophages in the fluid.


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19 July 2016 haematology and biochemisty from VetPath Laboratory


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12 August 2016


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CASE HISTORY:

DOES OLIVER HAVE FIP?

Cat’s name ............... Oliver ............................................................ .........................

Breed ......................................... Age......9m............Sex.......Male

neutered....................................

Other cats? .......................... Indoor/Outdoor ......Single cat

household............................................

How could this cat have gotten FCoV infection? ............................................... ...........

............................................................................................................................ .............

How long ago might the cat have become infected? ........................................ ..............


Recent stress? .................................................................................................. ...............

Clinical signs ...... Presentation: dyspnoea ...................................................................

Respiratory rate: 72 bpm (tachypnoeic) ..........................................................................

Auscultation: respiratory sounds reduced ......................................................................

Mucous membranes: pale ………………………………………………………...........

..........................................................................................................................................

..........................................................................................................................................


Other


Albumin 22

Globulin 75

Alb:glob

Bilirubin

AGP 1900

FCoV

antibody titre

>1280

FCoV RT-

PCR

Not

advised

Positive

Hct

Lymphocytes

Cytology NA

Other

NA = not applicable


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Conclusion: I believe/do not believe this cat has FIP because ........................................

..........................................................................................................................................

Treatment / next diagnostic action ................................................... ..............................

..........................................................................................................................................

NON-EFFUSIVE FIP

Step 1: Non-effusive (“dry”) FIP – history

Step 1 is pretty much the same as for effusive FIP, except that the incubation time

from becoming infected with FCoV, and even from the stressor, may be much longer

– many weeks, even months.

Step 2: Non-effusive (“dry”) FIP – clinical signs

Non-effusive FIP is the more chronic of the two forms of FIP, incubating months to

even years after the initial FCoV infection and the triggering stress. The dry FIP cat

loses weight gradually, is chronically or intermittently pyrexic (up to 103oF / 39

oC),

and becomes dull and anorexic. Most cats with dry FIP also have palpably enlarged

mesenteric lymph nodes and intraocular lesions, although the latter may be quite

subtle and require a thorough examination to detect.

If you understand that FIP is an immune-mediated vasculitis it becomes easier to

understand how it is able to manifest with so many varied clinical signs. Any blood

vessel to any organ can be affected and the clinical signs will result from the impaired

Key message: 80% of cats diagnosed with non-effusive FIP turn out

to have some other condition

Key message: cats with non-effusive FIP are not clinically well!

Cats with non-effusive FIP do NOT have a normal temperature, normal appetite, they are

not bright and responsive. Too many healthy cats with positive FCoV antibody or RT-

PCR tests have been erroneously diagnosed as having dry FIP and euthanased.


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blood supply and the developing granulomata in that organ. In non-effusive FIP,

fewer blood vessels are affected and the immune response is more chronic, leading to

larger pyogranulomata, which may even be mistaken for tumours. Clinical signs

depend on which organs are involved, examples include:

liver infiltration leading to jaundice

meninges/hydrocephalus leading to neurological signs (ataxia, nystagmus,

seizures, loss of reflexes); pyogranulomata around a nerve/ spinal column

leading to neurological signs

eyes: uveitis, aqueous flare, vitreous flare, retinal vessel cuffing, corneal

precipitates, haemorrhage into anterior or posterior chambers

mesenteric lymph node enlargement

pyogranulomata on the kidneys, leading to renomegaly

a colonic form of non-effusive FIP is recognised presenting with large

intestinal diarrhoea or constipation

Step 3: Non-effusive (“dry”) FIP – haematology and blood biochemistry

Haematology

In non-effusive FIP there is often lymphopenia; a mild non-regenerative anaemia with

a haematocrit of 30% or less (becoming severe as the FIP progresses); sometimes a

neutrophilia with a shift to the left. Unfortunately these haematological changes are

common to a vast array of chronic diseases in the cat, not just FIP. Haematology

examination is especially useful in differentiating FIP from feline infectious anaemia

infection where the anaemia is regenerative and there may be haemotropic

Mycoplasma spp organisms on the erythrocytes visible in a blood smear. Other

indicators of infectious anaemia as the diagnosis, rather than FIP, are an enlarged

spleen, extremely high temperatures (104-5oF, 40oC) cycling at 7-10 days, and a

response to doxycycline treatment.

Hypergammaglobulinaemia resulting in low albumin:globulin ratio (A:G) ratio

In FIP the globulin concentration in serum or plasma is raised to over 45g/l.

Consequently the A:G is usually lowered. An A:G of < 0.4 indicates FIP is quite

likely, provided that globulins are raised. However, remember than a low albumin

(e.g. in liver disease) can also artificially lower the A:G, so normal globulin likely

rules out FIP even if the A:G is low.

An A:G of >0.8 rules out FIP. A:G of between 0.4-0.8 is inconclusive, so consider

other parameters.

Bilirubin levels are often raised, although other liver parameters may be normal.

Rising bilirubin levels are a poor prognostic sign.Tsai et al

Key message: a negative FCoV antibody test is useful in ruling out FIP.

(Provided the test is sensitive enough.)


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20

A negative FCoV antibody test, provided the test is a good quality test with good

sensitivity, rules out non-effusive FIP (see FCoV antibody test section above). FCoV

antibody titres in dry FIP are usually extremely high.

Note: many healthy cats and cats with diseases other than FIP have FCoV

antibodies. The presence of FCoV antibodies alone is NOT diagnostic of FIP, if the

other parameters of the profile do not indicate a diagnosis of FIP.

I am quite appalled at how often a diagnosis of FIP is made on the basis of a high

FCoV antibody titre alone with absolutely NO other supporting evidence for such a

diagnosis.

On CSF analysis, the presence of FCoV antibodies is possibly more useful for

diagnosing neurological FIP than is the detection of viral RNA by RT-PCR since the

latter is sometimes positive in non-FIP cases.

Step 4: specialised laboratory tests

Alpha one acid glycoprotein

Alpha one acid glycoprotein (AGP) is an acute phase protein which has been shown

to be very useful in distinguishing FIP from other clinically similar conditions. Cats

with non-effusive FIP tend to have lower AGP levels than cats with effusive FIP, but

it is still at least twice normal (normal is up to 500 μg/ml). However, AGP rises in any

infectious or inflammatory condition, and also after surgery.

In non-infectious liver disease and neoplasia, which are the most common conditions

mistaken for non-effusive FIP, AGP is usually normal.

Pathology and histopathology on the deceased cat

Histopathology is generally regarded as the gold standard of FIP diagnosis:

histopathologists look for a perivascular pyogranuloma. In non-effusive FIP there

tends to be fewer (but often larger) lesions than in effusive FIP and often a full

exploratory laparotomy or post mortem is required to find the lesions. Grossly, FIP

lesions can be indistinguishable from tumours, necessitating histopathology to

differentiate. Some cats only have lesions in the brain, spinal cord or eye which

necessitates special instruments to access.

Sending an eye for histopathology: for light microscopy: Davidson's solution or

Bouin's solution are the routine fixatives used for the eye. Either of these provides

adequate preservation of tissues and should be used for all globes. Formalin should

not be used on globes if this can be avoided because it does not provide adequate

Key message: positive FCoV serology is NOT DIAGNOSTIC OF FIP


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21

preservation of the retina in particular. It should be limited to adnexal tissue. www.vetmed.ucdavis.edu/courses/vet_eyes/eye_path/epath_overview_index.html

Sending the entire body to the laboratory is more likely to result in diagnosis

than sending organ samples

Cave et al 2002

reported that sending an entire deceased kitten to the pathology

laboratory at Glasgow Veterinary School was more likely to result in a diagnosis than

simply sending samples of organs.

Biopsy /Trucut/ Punch biopsy / Fine needle aspirate

FIP can be successfully diagnosed by observing lesions typical of FIP in smear

preparations of FNAs or Tru-cut biopsies of the liver or kidney, although there was a

problem that many of the samples were inadequate (the cytology ruined) which meant

sensitivity was relatively low. Giordano et al, 2005

However, I have an ethical problem with

putting a cat who may be doing through such an invasive procedure.

FCoV can be detected in a fine needle aspirate of the mesenteric lymph node Kwok

et al, manuscript in preparation It is wise, if you are taking fine needle aspirates or biopsies for

FIP diagnosis to divide your samples into two and put one into 0.25ml saline, not

formaldehyde, so that FCoV RT-qPCR can be performed if histopathology doesn’t

give you an answer. Store the FNA in the fridge or freezer if you do not want to do

FCoV RT-PCR on it immediately: FCoV RNA will remain detectable for many weeks

there. Addie personal observation

Detection of virus by immunohistochemistry: can get false positives

Immunohistochemistry (IHC) is used to demonstrate the presence of virus in the

lesions of FIP, it has been considered the absolute gold standard in FIP diagnosis,

although I believe it will be surpassed by RT-PCR tests. It can be a useful

confirmatory test in cases in which the histologic findings are not typical of FIP.

However, it is essential that the correct controls are in place (i.e., that a non-FCoV

antibody is used as a control on every organ section being examined, since feline

tissue is sticky and will often non-specifically bind irrelevant antibody, for example

the conjugated antibody being used to detect the antibody detecting the coronavirus).

Lack of these controls will result in false positive diagnoses of FIP and a large chain

of veterinary laboratories has been known to give false positive diagnoses of FIP

using this technique.

RT-PCR for detection of FCoV RNA

Reverse transcriptase polymerase chain reaction (RT-PCR) detects the RNA of the

FCoV: i.e. is a test which detects presence of actual virus. Quantitative RT-PCR

(RT-qPCR) allows the amount of virus in the sample may be measured. Confusion

can arise because quantitative RT-PCR is sometimes referred to as “real time” which

may also be shortened to RT. In the early days it was referred to as Taqman PCR after

the first quantitative PCR machine. RT-PCR of faecal samples is useful in control of

FCoV infection in households of healthy cats and RT-PCR is useful in FIP diagnosis

on organs of cats in biopsy or post mortem specimens.


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In non-effusive FIP, detection of large amounts of virus in a fine needle aspirate of a

mesenteric lymph node is highly indicative of FIP Kwok et al, manuscript in preparation.

Blood samples are usually negative, so testing them is not useful. Detection of FCoV

RNA in the faeces is not diagnostic of FIP, since around 33% of healthy seropositive

cats, or animals with non-FIP illness, are also positive.

CSF

Detecting FCoV in the CSF of cats is not diagnostic of FIP: healthy cats and cats with

non-FIP conditions are occasionally positive (detecting FCoV antibody in the CSF

may be more useful).

Key message: DO NOT get FCoV RT-PCR tests on blood: they are a waste of

time and resources


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CASE HISTORY: DOES ZENA HAVE FIP?

Cat’s name ...........Zena................................................................ ..................................

Breed .....Maine Coon............. Age...9m..........Sex....................... ..................................

Other cats? ...1 - Buffy.........Indoor/Outdoor .................................... .............................

Recent stress? ................................................................................. ................................

Clinical signs .........Keratic precipitates............................................. ...........................

..........................................................................................................................................

..........................................................................................................................................

Test Blood Effusion Normal

range


Albumin 23 g/l NA 26-36 g/l

Globulin 91g/l NA 27-45 g/l

Alb:glob 0.25 NA

Bilirubin

AGP 1400

microg/ml

up to 500

µg/ml

FCoV

antibody titre

>1280

FCoV RT-

PCR

Hct 31.7 30-45

Lymphocytes

Cytology NA

Other

NA = not applicable


Conclusion: I believe/do not believe this cat has FIP because ........ ............. ............. ..

..........................................................................................................................................

.......................................................................... ............. .................................................

Treatment/next diagnostic action ...................................................................................

.........................................................................................................................................

..........................................................................................................................................

What is Zena’s prognosis? ..............................................................................................

..........................................................................................................................................


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CASE HISTORY: DOES BUFFY HAVE FIP?

Cat’s name ........Buffy...................................................................... ..............................

Breed ..........Maine Coon........... Age.......1 yr......Sex....................... ............................

Other cats? ...Zena...........Indoor/Outdoor .................................... .................................

Recent stress? ................................................................................. ................................

Clinical signs ........In contact with Zena. Eyes OK. ......................... .............................

..........................................................................................................................................

..........................................................................................................................................

Test Blood Effusion Normal

range


Albumin 38 g/l NA 26-36 g/l

Globulin 32 g/l NA 27-45 g/l

Alb:glob NA

Bilirubin

AGP 280µg/ml up to 500

FCoV

antibody titre

>1280

FCoV RT-

PCR

Hct 48.3 30-45

Lymphocytes

Cytology NA

Other

NA = not applicable


Conclusion: I believe/do not believe this cat has FIP because ....... ................................

..........................................................................................................................................

..........................................................................................................................................

Treatment/next diagnostic action ..................................................... ..............................

..........................................................................................................................................

What is Buffy’s prognosis? .............................................................. ..............................

What follow up tests might you do?.................................................. .............................

....................................................................................................................................


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CASE HISTORY: DOES TOMMY HAVE FIP?

For each aspect of the FIP diagnosis algorithm,

please put:

a tick ( ) for any result consistent with

FIP

a cross (X) for any result against a

diagnosis of FIP

and if you are not sure, or it’s ambiguous,

a question mark (?)

At the end of working through the algorithm, you

should have a preponderance of either ticks or

crosses.

Step 1: has Tommy had an opportunity to become infected with FCoV?

Tommy is a MN DSH of unknown age who came from a 28 cat rescue fosterer in 2006

along with one other cat. He is now in a 3 cat household in a rural area with

indoor/outdoor access. The third cat (DSH) was obtained in 2007 from a farm. The

cats have not been to a boarding cattery. He was presented in 2009 with the clinical

signs seen in the photograph below.

Is there anything else you noticed about Tommy’s history which could point the way

towards his diagnosis?

_____________________________________________________________________

_____________________________________________________________________

Step 2: Tommy’s clinical signs


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In the photograph above you can see Tommy’s main presenting signs, and below are

his clinical notes for any signs you can’t readily obtain from the photo:

T. 38.9

Appetite variable

Mesenteric lymph nodes not enlarged

Mucous membranes did not appear icteric

1. Are you thinking effusive or non-effusive FIP? ___________________________

2. Are his eyes normal? Describe what you see ______________________________

_____________________________________________________________________

_____________________________________________________________________

Step 3: In-house blood results

These are photos of the in-house blood results for you to extract the relevant

information from:


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Cat’s name .................. Tommy ...................................................... .............. ..............

Breed ......................................... Age.......old...........Sex............MN............................. .

Other cats? .......................... Indoor/Outdoor ................................................................

How could this cat have gotten FCoV infection? .........................................................

........................................................................................................................................

Clinical signs .................................................................................................................

..........................................................................................................................................

..........................................................................................................................................

How long ago might the cat have become infected? ......................................................


Recent stress? .................................................................................................................


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Other


Albumin

Globulin

Alb:glob

Bilirubin

AGP

FCoV

antibody titre

FCoV RT-

PCR

Hct

Lymphocytes

Cytology NA

Other

NA = not applicable


Conclusion: I believe/do not believe this cat has FIP because ........ ...............................

..........................................................................................................................................

..........................................................................................................................................


..........................................................................................................................................


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CASE HISTORY: DOES BASIL HAVE FIP?

Cat’s name .............. Basil ............................................................ ............................

Breed ......................................... Age..................Sex..........MN....................................

Other cats? .......................... Indoor/Outdoor ...............................................................

How could this cat have gotten FCoV infection? .......... Basil’s history was that he

was in contact with 4 other cats who have died of FIP. ..............................................

.......................................................................................................................................

Clinical signs .... He presented with jaundice. ...............................................................

..........................................................................................................................................

How long ago might the cat have become infected? ......................................................


Recent stress? ..................................................................................................................

Test Blood

5/1/04

Effusion Unknown/

Other


Albumin 24

Globulin 61

Alb:glob

Bilirubin

AGP 2600

FCoV

antibody titre

640

FCoV RT-

PCR

Not

advised

No

effusion

Hct 28.2

Lymphocytes 0.29

Cytology NA

Other

NA = not applicable


Conclusion: I believe/do not believe this cat has FIP because .......................................

..........................................................................................................................................

..........................................................................................................................................

Treatment / next diagnostic action ................................................... ..............................

..........................................................................................................................................


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Recommended suppliers of FCoV antibody tests

To obtain a FCoV Immunocomb kit contact Len Small: [email protected]

To obtain F-Corona Speed tests contact your Virbac representative.

Recommended laboratories for getting a FCoV RT-PCR test

France, Spain: Scanelis Laboratory: http://www.scanelis.com

Portugal: FACULDADE DE MEDICINA VETERINÁRIA, LABORATÓRIO

DE VIROLOGIA E IMUNOLOGIA, Avenida da Universidade Técnica, Polo

Universitário da Ajuda, Alto da Ajuda

http://hospital.fmv.utl.pt/index.php/microbiologia

UK: Veterinary Diagnostic Services, University of Glasgow Veterinary School (we

receive samples from all over the world):

http://www.gla.ac.uk/schools/vet/cad/submitasample/

References

Addie D.D., Jarrett O. 1992 A study of naturally occurring feline coronavirus infection in

kittens. Vet. Rec. 130 133-137

Addie D.D., Toth S., Murray G.D., Jarrett O. 1995 The risk of feline infectious peritonitis in

cats naturally infected with feline coronavirus. Am. J. Vet. Res. 56 4 429-434

Addie D, Belak S, Boucrat-Baralon C, Egberink H, Frymus T, Gruffydd-Jones T, Hartmann

K, Hosie MJ, Marsilio F, Lloret A, Lutz H, Pennisi MG, Radford AD, Thiry E, Truyen U,

Horzinek MC. 2009 Feline infectious peritonitis. ABCD guidelines on prevention and

management. J Feline Med Surg. 11 (7) 594-604.

Addie DD, McDonald M, Audhuy S, Burr P, Hollins J, Kovacic R, Lutz H, Luxton Z, Mazar S,

Meli M. 2012 Quarantine protects Falkland Islands (Malvinas) Cats from Feline Coronavirus

Infection. J Feline Med Surg 14 2 171-176

Addie DD, le Poder S, Burr P, Decaro N, Graham E, Hofmann-Lehmann R, Jarrett O,

McDonald M, Meli ML. 2015 Utility of feline coronavirus antibody tests J Feline Med Surg

17(2):152-62

Cave TA, Thompson H, Reid SWJ, Hodgson DR, Addie DD. 2002 Kitten mortality in the

United Kingdom: a retrospective analysis of 274 histopathological examinations (1986-2000).

Vet Rec 151: 497-501

Cohen TM, Blois S, Vince AR. 2016 Fatal extraintestinal toxoplasmosis in a young male cat

with enlarged mesenteric lymph nodes. Can Vet J 57, 5: 483-486

http://www.scanelis.com/

http://hospital.fmv.utl.pt/index.php/microbiologia

http://www.gla.ac.uk/schools/vet/cad/submitasample/


www.catvirus.com

31

Doenges SJ, Weber K, Dorsch R, Fux R, Fischer A, Matiasek LA, Matiasek K, Hartmann K

2015 Detection of feline coronavirus in cerebrospinal fluid for diagnosis of feline infectious

peritonitis in cats with and without neurological signs. J Feline Med Surg.

Doenges SJ, Weber K, Dorsch R, Fux R, Hartmann K. 2016 Comparison of real-time reverse

transcriptase polymerase chain reaction of peripheral blood mononuclear cells, serum and

cell-free body cavity effusion for the diagnosis of feline infectious peritonitis. J Feline Med

Surg. [Epub ahead of print]

Felten S, Weider K, Doenges S, Gruendl S, Matiasek K, Hermanns W, Mueller E, Matiasek

L, Fischer A, Weber K, Hirschberger J, Wess G, Hartmann K. 2015 Detection of feline

coronavirus spike gene mutations as a tool to diagnose feline infectious peritonitis. J Feline

Med Surg. [Epub ahead of print]

Fischer Y, Sauter-Louis C, Hartmann K. 2012 Diagnostic accuracy of the Rivalta test

for feline infectious peritonitis. Vet Clin Pathol. 41(4):558-67.

Giordano A, Spagnolo V, Colombo A, Paltrinieri S. 2004 Changes in some acute phase

protein and immunoglobulin concentrations in cats affected by feline infectious peritonitis

(FIP) or exposed to feline coronavirus infection. Veterinary Journal 167 1 38-44

Giordano A, Paltrinieri S, Bertazzolo W, Milesi E, Parodi M. 2005 Sensitivity of Tru-cut and

fine-needle aspiration biopsies of liver and kidney for diagnosis of feline infectious

peritonitis. Veterinary Clinical Pathology. 34 4 368-374

Giori L, Giordano A, Giudice C, Grieco V, Paltrinieri S. 2011 Performances of different

diagnostic tests for feline infectious peritonitis in challenging clinical cases. J Small Anim

Pract. 52(3):152-7.

Hartmann K, Binder C, Hirschberger J, Cole D, Reinacher M, Schroo S, Frost J, Egberink H,

Lutz H, Hermanns W. 2003 Comparison of different tests to diagnose feline infectious

peritonitis. J Vet Intern Med. 17(6): 781-790.

Hartmann K, Addie D, Belák S, Boucraut-Baralon C, Egberink H, Frymus T, Gruffydd-Jones

T, Hosie MJ, Lloret A, Lutz H, Marsilio F, Möstl K, Pennisi MG, Radford AD, Thiry E,

Truyen U, Horzinek MC. 2013 Toxoplasma gondii infection in cats: ABCD guidelines on

prevention and management. J Feline Med Surg. 15(7):631-7

Ishida T, Shibanai A, Tanaka S, Uchida K, Mochizuki M. Use of recombinant feline

interferon and glucocorticoid in the treatment of feline infectious peritonitis. J Feline Med

Surg. 2004; 6(2):107-109.

Jeffery U, Deitz K, Hostetter S. 2012 Positive predictive value of albumin: globulin ratio

for feline infectious peritonitis in a mid-western referral hospital population. J Feline Med

Surg. 14(12):903-5.

Korman RM, Cerón JJ, Knowles TG, Barker EN, Eckersall PD, Tasker S. 2012 Acute phase

response to Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' infection

in FIV-infected and non-FIV-infected cats. Vet J. 193(2):433-8

Legendre AM, Bartges JW. Effect of Polyprenyl Immunostimulant on the survival times of

three cats with the dry form of feline infectious peritonitis. J Feline Med Surg 2009; 11 624-

626.

http://www.ncbi.nlm.nih.gov/pubmed/25736448


http://www.ncbi.nlm.nih.gov/pubmed/?term=Doenges%20SJ%5BAuthor%5D&cauthor=true&cauthor_uid=26787293

http://www.ncbi.nlm.nih.gov/pubmed/?term=Weber%20K%5BAuthor%5D&cauthor=true&cauthor_uid=26787293

http://www.ncbi.nlm.nih.gov/pubmed/?term=Dorsch%20R%5BAuthor%5D&cauthor=true&cauthor_uid=26787293

http://www.ncbi.nlm.nih.gov/pubmed/?term=Fux%20R%5BAuthor%5D&cauthor=true&cauthor_uid=26787293

http://www.ncbi.nlm.nih.gov/pubmed/?term=Hartmann%20K%5BAuthor%5D&cauthor=true&cauthor_uid=26787293

















www.catvirus.com

32

Longstaff L, Porter E, Crossley VJ, Hayhow SE, Helps CR, Tasker S. 2016 Feline

coronavirus quantitative reverse transcriptase polymerase chain reaction on effusion samples

in cats with and without feline infectious peritonitis JFMS in press

Meli ML, Burr P, Decaro N, Graham E, Jarrett O, Lutz H, McDonald M, Addie DD. 2013

Samples with high virus loads cause a trend toward lower signal in feline coronavirus

antibody tests. J Feline Med Surg 15 4 295 – 299

Paltrinieri S, Parodi MC, Cammarata G. 1999 In vivo diagnosis of feline infectious peritonitis

by comparison of protein content, cytology, and direct immunofluorescence test on peritoneal

and pleural effusions. J Vet Diagn Invest. 11(4):358-61.

Porter E, Tasker S, Day MJ, Harley R, Kipar A, Siddell SG, Helps CR. 2014 Amino acid

changes in the spike protein of feline coronavirus correlate with systemic spread of virus from

the intestine and not with feline infectious peritonitis. Vet Res. 45:49.

Pozza ME, Stella JL, Chappuis-Gagnon AC, Wagner SO, Buffington CA. 2008 Pinch-

induced behavioral inhibition ('clipnosis') in domestic cats. J Feline Med Surg. 10(1):82-7.

Riemer F, Kuehner KA, Ritz S, Sauter-Louis C, Hartmann K 2015 Clinical and laboratory

features of cats with feline infectious peritonitis - a retrospective study of 231 confirmed

cases (2000-2010). J Feline Med Surg.

Ritz S, Egberink H, Hartmann K. Effect of feline interferon-omega on the survival time and

quality of life of cats with feline infectious peritonitis. J Vet Intern Med. 2007; 21(6):1193-

7.

Rohrer C, Suter PF, Lutz H. 1993. The diagnosis of feline infectious peritonitis (FIP): a

retrospective and prospective study. Kleinterpraxis 38 6 379-389

Simons FA, Vennema H, Rofina JE, Pol JM, Horzinek MC, Rottier PJ, Egberink HF. 2005 A

mRNA PCR for the diagnosis of feline infectious peritonitis. J Virol Methods. 124(1-2):111-

6.

Soma T, Wada M, Taharaguchi S, Tajima T. 2013 Detection of ascitic feline coronavirus

RNA from cats with clinically suspected feline infectious peritonitis. J Vet Med Sci.

75(10):1389-92.

Tsai HY, Chueh LL, Lin CN, Su BL. 2011 Clinicopathological findings and disease staging

of feline infectious peritonitis: 51 cases from 2003 to 2009 in Taiwan. J Feline Med Surg.

13(2):74-80.













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Feline Infectious Peritonitis (FIP) diagnosis worksheet

Dr Diane D. Addie

www.catvirus.com

Cat’s name ....................................................................................... ...............................

Breed ......................................... Age..................Sex....................... ............... ...............

Other cats? .........................Indoor/Outdoor .................................... ............... ...............

Recent stress? ................................................................................ ............... .................

Clinical signs ...................................................................................................................

..........................................................................................................................................

.......................................................................... ............... ............... ............... ...............


Other


Albumin

Globulin

Alb:glob

Bilirubin

AGP

FCoV

antibody titre

FCoV RT-

PCR

Not

advised

Hct

Lymphocytes

Cytology NA

Other

NA = not applicable


Conclusion: I believe/do not believe this cat has FIP because ........ ............... ...............

..........................................................................................................................................

..........................................................................................................................................

..........................................................................................................................................

34

FIP diagnostic flowchart Step 1 for the cat’s guardian to complete

Download the FIP diagnosis algorithm from www.catvirus.com to take to your veterinary surgeon.

You can help your vet by filling in this questionnaire first and giving it to him or her. The tables are

only step 1 of the FIP diagnosis algorithm and are designed simply to save time in the veterinary

surgery and to help you to give your veterinarian history relevant to make a correct diagnosis.

Step 1. Question 1. Where/how could your cat have caught FCoV?

FIP can only develop in a cat who has been infected with feline coronavirus (FCoV) – it cannot

occur out of the blue. Go through the following questions to try to establish whether or not your cat

has had the chance to become infected.

Score through or circle the Yes or No

My cat is pedigree (purebred) Yes / No

I have more than 6 cats and they use litter trays Yes / No

My cat came from a rescue shelter Yes / No

My cat has been in a boarding cattery Yes / No


My cat has been to a cat show in the last year Yes / No

My cat has visited a stud cat in the last year Yes / No

A queen visited my stud cat in the last year Yes / No

If the answer is Yes to any of the questions above, then your cat has possibly had the opportunity to

become infected with FCoV.1 If you answered No to all of the questions above, then FIP seems

unlikely, but is not completely ruled out.

Step 1. Question 2. Has the cat experienced a stress in the last 18 months?

We only got the cat within the last year Yes / No

My cat has or had another illness recently Yes / No


We recently got a dog or puppy Yes / No

We recently had a baby or adopted a child Yes / No

We have 6 or more cats Yes / No

We have moved house in the last year Yes / No

We put the cat into a boarding cattery Yes / No

Somebody the cat loves has been away, or ill, or died Yes / No

The cat recently gave birth Yes / No

We took our cat to a cat show Yes / No

The cat was hospitalised at the veterinary surgery Yes / No

The cat has been on some other kind of journey Yes / No

The cat has been exposed to some other stress not listed here Yes / No

If the answer is yes to any of the questions above, then your cat has likely experienced stress. If

you answered No to all of the questions, try to think if your cat has experienced a stress which I

have not listed. If you answered no to all the questions in step 1, FIP seems very unlikely: take

your answers and the algorithm to your veterinary surgeon and discuss the situation with him or her.

1 If you said Yes to one of the possible sources of FCoV infection that does not necessarily mean that your cat became infected from

that source – there is often more than one possible source for becoming infected.


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Protocol for treating effusive FIP

Dose

Glucocorticoids:

Dexamethasone

1 mg/kg intrathoracic or intraperitoneal injection sid up to 7d, (stop if

effusion disappears sooner) AND:

Prednisolone

sliding dose:

(Anti-inflammatory

dose.)

2 mg/kg/day for 10-14 days, reducing to

1mg/kg/day for 10-14 days, then

0.5 mg/kg/day for 10-14 days, then


0.25 mg/kg/e.o.d. …… and so on

ceasing after complete remission of clinical signs and return to normal of

AGP and globulins

If, at any point, the cat’s condition regresses, go back to the previous dose.

Virbagen Omega:

(Virbac)

1 million units/kg into the abdominal or thoracic cavity after draining the

fluid, e.o.d reducing to once weekly if remission occurs. Subcutaneous

injections can be given instead if preferred, but interferons act locally and

every effort should be made to get the treatment as close to the site of

infection as possible.

***


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Protocol for treating non-effusive FIP

Key message: BE ABSOLUTELY CERTAIN THE CAT HAS FIP BEFORE EMBARKING

UPON TREATMENT

In some ways this is a more important message in non-effusive FIP than in effusive FIP, since to

immunosuppress cats with lookalike infectious conditions such as toxoplasmosis or leishmania

would be catastrophic.

Dose

Corticosteroids

Prednisolone sliding

dose:

(Immunosuppressive

dose)

2-4 mg/kg/day for 10-14 days, reducing to

1-2 mg/kg/day for 10-14 days, then



0.25 mg/kg/e.o.d. …… and so on

ceasing after complete remission of clinical signs

If, at any point, the cat’s condition regresses, go back to the previous dose.

For FIP-related uveitis, topical corticosteroids may also be used.

Recombinant feline

interferon omega

(Virbagen Omega,

Virbac)

100,000 U per cat orally s.i.d until AGP, globulins, bilirubin, Hct,

lymphocyte count and clinical signs return to normal.

Diluting Virbagen Omega (IFN Ω):

Virbagen Omega comes in vials of 10 million units. It is reconstituted with

1ml of diluent. To get 100,000 Units/ml, use a 1ml syringe and put 0.1 ml

IFN Ω into 5 mls of water or saline: teach the guardian to give 0.5 ml of

this per day by mouth. (Store it in the fridge (where it will last up to 3

wks). Divide the remaining IFN into 9 x 0.1ml aliquots and freeze until

needed: these syringes will last up to 6 months in the freezer. One 10MU

vial will treat a dry FIP cat for almost 3 months.

Polyprenyl Immunostimulant

Polyprenyl Immunostimulant (Sass & Sass, Inc, Oak Ridge, TN 37830, USA) is a mixture of

phosphorylated, linear isoprenols which upregulates biosynthesis of Th-1 cytokine mRNAs. It was

used successfully in three cats with non-effusive FIP, with survival times of 14 months, over 26 and

27 months, but had no beneficial effect on cats with effusive FIP. Legendre & Bartges, 2009

However,

Legendre presented at AAHA that 22% of 58 cats with FIP were alive at 6 months, and only 5% at

one year. The dose of 3mg/kg orally is given three times a week until cure or death. I await a report

of a controlled clinical trial with interest and suspend judgement until there is more evidence.

Concurrent corticosteroids are not advised.

One needs permission from the VMD to import it into the UK and it can be purchased from the

Vetimmune website. For the latest on PPI availability in Europe and further information on FIP

treatment visit the FIP treatment page of my catvirus website.

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EFFUSIVE FIP DIAGNOSIS ALGORITHM


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NON-EFFUSIVE FIP DIAGNOSIS ALGORITHM


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FCOV ENTERITIS DIAGNOSIS ALGORITHM


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Documents

Dr Soma’s probability of wet FIP table 3 workbook and FIP... · In the first edition of my book for cat guardians, Feline Infectious Peritonitis and Coronavirus, I made the statement