Immune mediated polyneuropathy

[KassieandArchie]

Hello, newbie here.

I have had a little look through the current chats and haven't spotted anything about immune mediated polyneuropathy. I understand it's quite unusual and each case varies significantly.

It would be great to hear anyone else's stories if you have a dog with this condition, my boy has just been diagnosed and we will be commencing with treatment next week.

The neurologist has recommended a course of steroids followed by an immunosuppressant. Is anyone else's dogs on similar treatment? Or seen results with an alternative treatment? The nerves affected with Archie are his cranial nerves which I believe is even more unusual.

I look forward to chatting with you!

Thanks, Kassie

[Jo CIMDA]

Hi Kassie and welcome

I am sorry Archie is unwell.  Polyneuropathy is such a broad  label and it can take form in many different ways. Has the vet narrowed it down to a specific diagnosis?  The most common immune mediated polyneuropathy  in dogs (and it isn't that common) is myasthenia gravis. 

What symptoms does Archie have?

Jo

[KassieandArchie]

Hi Jo,

Thank you for your message. The diagnosis was from a neurologist after an MRI and CSF tap. He didn't say there was a specific known syndrome for the symptoms Archie has. So we just have the diagnosis of 'immune mediated polyneuropathy affecting the cranial nerves'

The symptoms he has are a head tilt to the left, and paralysis of the left side of his face - doesn't blink his left eye and when he pants the left side of his mouth droops. The rest of his body is unaffected and his QoL is also unaffected so far, but we have been told that this could spread to other cranial nerves which could be fatal.

His muscles were also checked for function and they are normal (although atrophied temporal muscles) so I think that rules out MG

Thanks again, Kassie

[Jo CIMDA]

Hi Kassie

These obscure neurological diseases can be tricky to diagnose and also, one successful treatment regimen won't necessarily be as successful in another dog.  This, unfortunately,  is the vagueness of neurological disease in dogs.

I am very interested to know how Archie is being treated - dose of steroids and duration etc.   As this is a relatively rare disease, it also may help others out there who are having similar problems with their dogs.  If Archie is on an immunosuppressive dose of prednsiolone then a  giving Archie a gastroprotectant such as omeprazole would be prudent.

I do hope Archie will improve soon. 

Jo

[KassieandArchie]

Good afternoon

I thought I'd drop a quick update about Archies progress here.

Following the diagnosis of 'immune mediated cranial polyneuropathy' we found out that his CSF results came back showing Staph. This was thought to most likely be contamination (😒) but it's was decided to be too risky to ignore. We treated with antibiotics for 1 month with no improvement.

In Archies case, nerves V, VII and VIII are affected.

Following from this we decided to treat with prednisolone (25mg twice daily) for 1 month. We are now just over 3 weeks in and he has regained some motor function to his left eye. Sensory function is still limited but small wins!

We have been monitoring side effects and thankfully he hasn't had any gut issues so a gastroprotectant wasn't used. He has however had lots of other side effects but the progress has outweighed these so we have continued with the treatment.

Going forward, we aim to reduce his dose to 15mg twice daily for a month and monitor progress. We have the option of adding in other anti-cancer drugs but we have decided not to do that just yet.

We have also added some vague physio to help rebuild his temporal muscles - lots of chewing to Archies delight!

Archie remains in good spirits and ever unaware of his wonky face!

Of course, if anyone has any experience with this please do share! I'd love to hear about any other pups in a similar boat, or if anyone has any questions about his condition I'd be happy to help if I can at all.

Kassie

[Jo CIMDA]

Hi Kassie

Thank you for the update and the good news that prednisolone is having some positive effect.   It is lovely that Archie is not bothered by his 'wonky' face and that he is doing well in other ways.

I would give a gastroprotectant, such as omeprazole, even though he is not exhibiting any adverse gastrointestinal signs because this can build up and cause gastric ulceration later on, and this causes more problems.   Unless there is good reason not to give a gastroprotectant, then why not?

I have not had a dog with polyneuropathy but I have had a dog that has had masticatory myositis affecting the muscles of the face, including those that affect chewing,  and temporal muscles, so I somewhat understand what Archie is experiencing. I presume the oesophageal muscles controlling his swallowing are not affected.  Now he has started on the prednisolone, and you have seen improvement, I am hoping that it will get no worse (because it is now under control)  but it will gradually get better.

Watch the adverse effect of prednsiolone, and reduce if necessary, even if it means introducing another immunosuppressive drug such as leflunomide or mycophenolate mofetil.

I look forward to the next update.

All the best
Jo

[KassieandArchie]

Hi Jo

Thanks for the response, it's nice(?) to hear someone else who has experienced similar problems, although not nice all the same!

So we are 2 weeks in to Archies reduced dose (15mg 2X daily) if prednisolone and he is pretty much back to his old self -side effects wise -which is amazing! It really shows that he must have been feeling pants on the higher dose.

His face has not changed, still limited sensory function, and motor function to his mouth. Maybe this will take time?

With the nerves that were shown to be affected on the MRI, I'm not sure if his swallowing is affected. He does seem to swallow more than normal but it isn't causing him any issues so hopefully that won't progress.

We still have two more dose reductions (each course is a month) before we reassess and decide which medication to go for - I'm not sure what our options are yet.

Will keep you updated!

Thanks again

Kassie

[Jo CIMDA]

Hi Kassie

It is quite amazing how quickly the body responds to a lower dose of preds. 

They key to success  is to gauge it by the clinical signs and be flexible as to when the next reduction is needed.   It is all about tailoring the protocol to the individual.  When the dose of preds is tolerable it is often better to reduce more gradually and taper off over a longer period of time, but the clinical signs of disease and side effects of the drug dictate.

Archie's face may not change but he doesn't know any difference and as long as he is a happy and healthy boy it doesn't matter.

It is going in the right direction.

Jo

[KassieandArchie]

Hi Jo

Another update. We dropped his second dose of prednisolone (15mg 2X daily) a week early as he was really suffering with side effects. He went down to 15mg 1X daily. This was great because he is nearly side effects free and back to his old energetic self, however we have relapsed with the progress in his face. I have been told that if a relapse occurs we are unlikely to get any improvement again. We will continue to wean off the steroids but I'm not sure what our next move will be.

Swings and roundabouts. Always.

Thanks, Kassie

[Jo CIMDA]

Hi Kassie

If Archie is not taking another immunosuppressive drug alongside prednisolone then I would ask your vet to seriously consider introducing one asap.  The 'combination' drug needs to be one that doesn't have a long lead-in time and can take effect within a few days.  Mycophenolate Mofetil and Leflunomide might be a consideration, another one which may take a few more days to kick in is cyclosporine.  I believe this is essential if remission is to be achieved.    Take a look at this link:

https://www.dvm360.com/view/immunosuppressive-drugs-beyond-glucocorticoids

I believe  you can get Archie back to where he was before and by using a combination drug you will achieve greater immunosuppression and you will be able to lower the preds quicker.  He responded to the drugs first time, so there is a good chance that he will respond this time.

You have to tailor the pred drug protocol  to the individual, and you have to respond to the clinical signs of the adverse effects however, 50% reduction, unless it is absolutely necessary, is not the best way to go.  A much slower reduction of 25% or even less, if you can, seems to lessen the side effects but continues to control the disease process.  Relapses are not uncommon, and in many ways can be expected, but you just raise the dose of drug to where it was before (or higher)  and control of the disease continues.  In Archie's case you probably had no choice but to lower the preds by 50% but because he hasn't got a back-up drug, he started to relapse.   This makes sense.

I do hope your vet will listen to you and introduce another immunosuppressive drug now.  What do you have to lose?

Jo

[KassieandArchie]

Hi Jo

Thanks so much for the info. So great to hear we have options!

The vet did offer mycophenolate but we decided not to add it at that point because I was a bit worried about the potential side effects of bone marrow problems and the need for frequent blood tests - especially during lockdown this seemed risky. I have a consult scheduled for tomorrow so will definitely see if it is worth adding at this point to get some of that function back.

It's great to see Archie back and happy but it has seemed like a toss between QoL and function! Maybe we can get both!

Will keep you posted!