Immune Mediated Neutropenia

[DAEllis]

Hi My name is Denise and my border collie Mist 3 years old has been diagnosed with IMN two months ago
Her neutrophils were not even registering on her blood tests she had after
Becoming lethargic and having raised temperature
Two
Months ago
She has had scans of major organs all
Okay and was started on Prednisidone for two weeks
30mg x1 a day
Blood tests after two weeks showed little or no improvement so she was given Mycophenolate
0.8 ml X2 a day and is
on amoxicillin broad spectrum antibiotic she has been on these
Now for two months her neutrophils have gone from not registering to 0.3
In two months
Vet Is suggesting a bone marrow aspiration to assess if there are blood cell precursors/immature cells or whether there is a cancer of the bone marrow/scar tissue/dead tissue instead The benefit of the procedure is that we may get a better understanding of her disease and how likely is to respond to treatment, although as discussed previously, it is unlikely that it will change our treatment options. She has also just developed  mild IMT in her last blood test results I am
So unsure what to do can anyone help and how long in reality should we keep her on the steroids should
We change do they need to be higher ? Should she have the bone marrow aspiration
Mist is coping okay at moment is thirsty and hungry and putting on weight but nothing else apart from obviously not wanting to play but manages to walk out in garden all the time
I see we should keep her away from other dog
Areas and we have been told she cannot have her vaccinations due in  July she has had them for the past three years is there anything else we could use instead for her vaccinations and wormer etc also
We were told by vet she could
Wear her Serocco flea and tick collar but I am unsure now ?
Any help
And advice would be appreciated Thankyou 🙏Denise

[Jo CIMDA]

Hi Denise and welcome

I am sorry your Mist has IMN. 

IMN is an uncommon immune mediated disease but I have known dogs to be successfully treated with a good immunosuppressive drug protocol. How much does Mist weigh?  She should be on 1mg/kg/12 hours prednisolone.  Mycophenolate is a very good combination drug to use alongside prednisolone therapy but the mainstay of treatment is usually prednisolone.  A dog cant stay on high doses of prednisolone for a long time.  The aim is to give enough pred that will significantly suppress the immune system (usually for about 3-4 weeks) and then reduce by 25% over a period of months in the hope that the immune system is stable and no longer targeting the neutrophils. Too much pred will cause severe side effects - too little will not suppress the immune system enough to achieve remission. The addition of a second immunosuppressive drug will add to immunosuppression and will likely allow the preds to be reduced sooner.  Below is the best immunosuppressive drug protocol that I have come across and it can confidently be used as a guide.   

Example: Reduction Protocol for prednisolone:
Clinical Immunology of the Dog & Cat , 2nd Edition,  by Michael J Day
Professor Michael DayBSc, BVMS(Hons), PhD, DSc, DiplECVP, FASM, FRCPath, FRCVS 

Professor of Veterinary Pathology, University of Bristol, UK and WSAVA - Chairman of Scientific Advisory Committee.
This example is based on a dog receiving an induction dose of 1.0mg/kg/q 12hrs (q = every)
Dose                           Duration (based on clinical effect)
1.0mg/kg/q 12h                          10-28 days
0.75mg/kg/q 12h                       10-28 days
0.5mg/kg/q 12h                         10-28 days
0.25mg/kg/q 12h                        10-28 days
0.25mg/kg/q 24h                        10-28 days
0.25-0.5mg/kg EOD                    at least 21 days
0.25-0.5 mg/kg every third day      at least 21 days

Every reduction is made after consideration to improvement of clinical signs, blood results and side effects of the drugs.
Prednisolone:  "Doses above 2.2mg/kg/day do not give more immunosuppression but do cause more side effects. Many internists believe that prednisolone doses should not exceed 80mg per day, regardless of the dog's weight."  Plumb's Veterinary Drug Handbook Eight Edition.


These are excellent links:

https://www.dvm360.com/view/it-immune-mediated-neutropenia
https://www.dvm360.com/view/immune-mediated-neutropenia-proceedings


Low neutrophils can also be due to cyclic neutropenia in grey collies.  Is Mist a grey or paler border collie?  This is a genetic disease but it is not an immune mediated disease and therefore it is treated differently.  This is a good link.

https://pubmed.ncbi.nlm.nih.gov/16610934/

The feature of cyclic neutropenia is, as the name suggests, the neutrophils fluctuate and can dramatically drop every 10-12 days  leaving the dog vulnerable to infections.  I am not sure if there is a genetic test for border collies who may have cyclic neutropenia.  There is one for smooth and rough collies. There are cases of border collies with cyclic Neutropenia referenced.

To have a bone marrow biopsy, Mist would have to be off of preds for at least 14 days. These tests are not always conclusive especially if the dog has been on steroids.  I don't know about the withdrawal time for mycophenolate.   Whether the withdrawal of immunosuppressive treatment would cause a relapse of IMN is unknown but it is very possible.   Sometimes, an immune mediated disease is assumed based on clinical signs and  blood results and treated accordingly - this is not uncommon because it is not always possible to obtain a definitive diagnosis. So, if Mist is not a grey collie then it is unlikely that she has cyclic neutropenia  and therefore diagnosis of  IMN is most likely and immunosuppressive treatment is the most obvious route - which it sounds like your vet has taken.

If a dog has been vaccinated as an adult then it is most likely that it will be immune for life to the core diseases in the UK.  The other
non-core diseases (leptospriosis etc...) don't have to be given and should be avoided in a dog with a genetic predisposition to autoimmunity,  along with regular preventative treatment such as flea and worming preparations as these have a potential to trigger AI diseases in predisposed dogs.  Please check out the WSAVA vaccination guidelines for guidance.   When I asked Prof Brian Catchpole, at a seminar held at the  Royal Veterinary college, if a dog with an IM disease should ever be vaccinated again, or spot on treatments used his reply was  -  NO! A dog who has had an immune mediated disease should never be vaccinated again and all treatments, especially if they are just preventative ones, should be avoided. Vaccination and some drugs/treatments are potential triggers for IM disease.  No one can tell you whether to vaccinate Mist in future but do the research and be happy with your decision.   If you see fleas or worms (presuming you pick-up after her, then treat accordingly.  You can have a faecal test done to check for worms. 

Mist should be on a gastroprotectant such as Omeprazole, to protect her tummy from excess acid and as IMN has not been confirmed, and she may be vulnerable to infections, perhaps antibiotics should be considered.

I hope the above helps.

Jo