Questions for the Neurologist
What do you do if you don’t have any history? ( I work in shelter med and get a lot of no history cases)
- Excellent Question! Short answer: You do your best! This situation makes it more challenging. Having worked with several shelters and rescue groups, I understand the struggle of this exact situation. In this scenario, I heavily rely on the breed of the animal and the location where the animal was found to develop differentials, then rank them based on likelihood and the extent to which I can address each differential. In some scenarios, I have also used an “unranked” differential list where I say, Okay, these are the most common differentials; it can be any of these. I think of it more as a “pool” of differentials rather than a ranked list. Then consider what diagnostics or therapies I can do to help me get the biggest bang for my buck. You may not be surprised to hear that even when the animals are owned and live with the family, sometimes the history is limited, and I end up using this “pool of differentials” approach.
Other than mentation changes/seizures, what are some common indicators that the neuro signs we are seeing in a Frencie/Doxie/small dog is NOT IVDD?
- Wonderful! A few things that have helped me include, most notably, when there is evidence of multiple locations being involved. MUO often presents as a multifocal presentation, so if you have proof that multiple locations of the cord are involved (for example, decreased reflexes in thoracic and pelvic limbs with no evidence of a lower motor neuron disease). Pain (or lack of) can be highly variable with both MUO and IVDD, surprisingly, so it isn’t a great indicator either way, but animals who are VERY painful in a focal area lean me towards disc and more diffuse pain towards MUO. Sometimes, it is a response to therapy that actually drives this when treating empirically. If I treat a paralyzed Frenchie with steroids and they get better, but then we start to wean and they slowly start getting worse again, that slow loss of therapy control often leans me towards MUO. The more dramatic the change, the more I can be convinced. Frenchies for sure are worse about getting myelitis without other signs (dachshunds at least have the dignity to sometimes show brainstem signs). Often, we don’t know until we start therapy and we start to see relapse that we can distinguish. Of course, IVDD can relapse, but short of pain like in a cervical disc situation, it usually isn’t as slow and insidious a relapse as the MUO tends to be. However, I wish it were as straightforward as this, but reality rarely matches expectations, and it can be more complicated than just – oh, they are slowly getting worse again. Ultimately, there is no “home run” (perhaps short of a multifocal presentation), but piecing together numerous context clues can raise suspicion. Most importantly, trust your gut! If the case feels “off” and not like a traditional dachshund, follow that instinct!
What do you look for in survey rads for discospondylitis?
- When looking for this, I am looking for two things primarily: 1.) Sclerosis/increased opacity of the end plate on either side of the vertebral body 2.) a lytic lesion or irregularity within the end plate. Often you have to compare both of these to the other disc spaces throughout the spine, especially the sclerosis, as I often think all end plates look a little brighter, but by comparing them to the others, you can get a sense of “normal” vertebral body endplates for that patient.
If a dog is deep pain negative and can’t afford surgery, does the risk of myelomalacia increase?
- It is simply the status of being deep pain negative that puts them at risk. I’m not aware of any studies examining whether there is an increased risk if they can’t get to surgery. Still looking at around a 10-15% chance, occurring within he first two weeks. One could theorize that maybe if there is a lesion and it continues to press on the cord more and more, but we don’t have any data to fully support it.
What kind of washout period do you like to use blw NSAIDS and steroids when NSAID are not working?.... ie dog dx'd at urgent care and not getting better...
- If I can get it, I’ll do a 3-5 day washout. If I need those steroids, ASAP for a ranging MUO, well. . . let’s just say I load them up on gastroprotectants and pray, and of course, talk to owners about the risks and pros and cons – note this is often due to concern for it being life-threatening. If it's cause, I think it is a cancer or other issue, and isn’t life-threatening, then I’ll shoot for the 5 days. I know of people who go up to 7 just to be safe.
What's your preferred test for degenerative myelopathy (ie embark, akc, etc)
- I personally send directly to Missouri, but have had many people go through the OFA website more recently.
What is your antibiotic of choice for empiric treatment of suspected otitis media and, if imaging not possible, how long do you continue for?
- Great question. If I can get info from a cytology, I might try that. Otherwise, I’ll often reach for Clavamox/Cephalexin or Cephalosporin in dogs and sometimes Clindamycin in cats for empirical therapy. If I really believe it is a deep infection, I’m going for around 6 weeks.
- Resources worth checking out: (should be open access)
o Cats: https://journals.sagepub.com/doi/10.1177/1098612X18764582
If no underlying condition found and you suspect microbleeds, how do you treat?
- Unfortunately, if no cause is identified (systemic disease, neoplasia, blood pressure), therapy is more nonspecific and symptomatic. Without identifying an underlying issue we aren’t sure how to prevent it or the best therapy. Continued monitoring for an underlying condition to develop is often my approach and may have a much more sentitive trigger finger when it comes to things like proteinuria or border line testing values than I normally would.
- Here is a great open access paper, worth looking at underlying causes: https://onlinelibrary.wiley.com/doi/full/10.1111/jvim.14730
Your last slide said hemangiomas met to the brain, but did you mean hemangiosarcoma?
- I did mean hemangiosarcomas – not sure why it corrected to hemangioma. Thank you!
Has it been observed in cats or dogs if they can have transient ischemia attacks prior to a full ischemic attack(aka the acute stroke?)How do address this w/o?
- To my knowledge, there has not yet been a connection between TIAs and full strokes unless we can identify an underlying condition. Full disclosure . . . we are really just in the last couple of years appreciating TIAs in terms of figuring out why they occur and a lot more work is going to be required to really get a sense of them. Of course, because the animals are normal by the time they present, we don’t get a lot of them to go do a workup. That being said, I think a TIA is a great reason to look for possible etiologies of vascular events such as endocrine, cardiac, or neoplastic conditions! If we identify one of those, then there is a higher risk of a full stroke.
In a dog with seizures and eosinophilic meningoencephalitis, will you see eosinophilia?
- Interestingly, compared to other MUOs we may see a higher likelihood of seeing peripheral eosinophilia! In one paper, 9/11 dogs showed peripheral eosinophilia when eosinophilic meningitis was diagnosed. Paper: https://doi.org/10.1111/jsap.12837
What's your pred taper protocol for dogs on IVDD if they are responding to it?
- I typically do a 1-2 week course with tapering every 3 to 5 days.
Well-controlled hypothyroid dogs should not exhibit vestibular signs, correct? I had one that we think developed idiopathic geriatric
- They can, but not from hypothyroidism, theoretically. I would believe this case to be more likely associated with idiopathic (geriatric) vestibular disease than secondary to hypothyroidism if we are well-controlled.
Do you have a resource for the polyneuropathy caused by hepatocellular carcinoma?
- From the human literature primarily and from one report in a dog, however, that dog presented more with a multifocal myelopathy, so it was not a true polyneuropathy. This comes from my experience with two dogs in my career that had suspected polyneuropathy in the presence of HCC. One was resolved after intervention, and the other did not pursue any action due to severe financial constraints. I am waiting for a third to hopefully publish as a case series. In the human literature, there is a rare association between polyneuropathy and HCC. I anticipate it is an extremely rare occurrence in vet med as well (perhaps more so). What I don’t know is if there is an association with the hypoglycemia paraneoplastic syndrome that is more commonly presented, and if that is what leads to it or not, as both had low normal glucose; in the human papers, they were inflammatory demyelinating polyneuropathies. My hope is that in any future cases (which may take years and years to collect at the current rate I’m going), we can do electrodiagnostic and/or biopsies.
What type of GI dz causes fly biting
- Gastro-esophageal reflux is the #1 thing that has been diagnosed in the cases that I have worked up with internal medicine for flybitting. This is also what they identified in this article: https://pmc.ncbi.nlm.nih.gov/articles/PMC3500118/pdf/cvj_12_1279.pdf
Do we see channelopathies in Veterinary Medicine?
- We do but they are poorly described overall. In talking about 3 years ago with another neurologist who just recently retired and studied movement disorders, he was using both bromide and zonisamide to help with cases of presumptive channelopathies.
From what pharmacy do you prescribe IN midazalam and R diazepam?
- When I was in private practice, I had to prescribe these directly from my hospital. I had two little “seizure rescue packs” that we made up using the small 2 ml bottles. I did eventually get a local pharmacy to start carrying the 2ml bottles, but the pharmacist when to the same undergrad as me. Since most human products come in prefilled syringes, this has become even more complicated getting things from the human pharmacy. There is debate about sending these products home in syringes. Pre-lining the syngrines can help, as can keeping them in the dark. How long they are truly effective, however, I’m not sure anyone fully knows. In the human world, they often replace every 3 to 6 months.
I’ve heard of people supplementing coconut oil for seizure control. Do you have a dose for coconut oil you like to use, or do you not do this?
- This comes from the idea of medium-chain triglycerides. There is no brand I am fond of; however, the studies conducted with MCTs had a 12- to 15% composition in the diet. That would be A LOT of coconut oil. I’ve had a few owners try it, .but I’m not sure if it did anything, However, I do tell them to beware if they have a history of pancreatitis.
Do you go back down to normal prescribed dose after the cluster dose is done?
- I do! I will usually use the pulse therapy for 48 hours after the last seizure, then go back to normal dosing.
How do you choose which AED to start a patient on?
- Great question! It depends on what my goals are! I have put some examples below
o If Seizure control/efficacy is the top priority: Phenobarbital
o If Low side effects/safety is the top priority: Keppra
o If history of liver issues: Keppra or KBr (not cats)
o If the owner says they can’t give meds more than once a day, KBr in dogs or Zonisamide in cats.
o There are lots of other contextual factors that could in theory play a role.
How many seizures is too many? Do you start a treatment for 1 single seizure? Ex: O who nonchalantly says on wellness exam pet had x1 within the last 6 months.
- For me, it’s 2 or more seizures within 3 months(ish). If it is within 6 months, it’s a gray zone. Anything more frequent is a fair trigger to start an AED. One seizure ever, then they get a “free pass,” as for me, it is how long until the next one. Meds aren’t going to do any better if the second one occurs 8 months later, but if it is 8 days later, then for sure. Now, if the seizures are prolonged, i.e, like the actual seizure activity is 2-3 minutes, that might lead me to pull the trigger on an anti-seizure medication. Cluster seizures, even if the first time, unless due to a known cause, will get started on an AED. Granted, many owners struggle with real timing, as in-the-moment time feels like forever. So getting them to videotape can be a great option!
What breeds are predisposed to lysosomal storage diseases?
- Great chart from JVIM 2022 in paper by Skelly and Franklin!
- https://doi.org/10.1111/j.1939-1676.2002.tb02344.x
Does Diplomyelia signs present immediately after birth or is it progressive?
- The reports are all over the place! I think a lot depends on what else is going on in terms of whether there are other congenital abnormalities. Often, these conditions have other issues, such as a meningocele, and we catch them early on. The literature supports this in the bovine species as it is often reported in calves. In one report, a dog didn’t present until they were 9, but had always had long-term bladder issues since 3 months of age, so clearly there were signs. Another presented at the age of 2 for a mass, but the history prior was unknown. Bladder signs tend to be commonly reported, but also some degree of atypical gait or weakness.
How quickly do you need to surgically correct exposure of meninges in newborns (for meningocele)?
- Most animals that we have seen are presented to us months after being born, which is shocking. We treated a dog at 2 months of age and a calf at 3 months of age. Granted, the sooner, the less likely secondary infection can creep in!
For steroid responsive meningitis arteritis (SRMA), how long is your typical course? Do you keep the animal immunosuppressed for life or do they recover within weeks?
- I usually do 6 - 12 months (often have transitioned them to some other immunosuppressant and off steroids or low dose of steroids by this point), then see if I can wean them off. If they relapse, then back on meds. Some sources recommend a minimum of 6 months for immunosuppression, and this would be the minimum I would be comfortable with.
Are there any concerns with speed of correction of sodium levels in an Addisonian patient being given DOCP? What are the major concerns with too high of a dosage of DOCP leading to hypernatremia? Are they the same concerns as hypernatremia due to a different cause?
- Great questions, and the answer is – it’s all about the time of how long they have been hyponatremic or hypernatremic and the severity. <110 and >180 are the most critical phases, but caution should still be exercised in patients not this severe! I have provided some resources below that delve further into these questions.
- One of the best discussions I have seen regarding hyponatremia was in this paper (written by the author of the primary ECC-ICU book!): https://onlinelibrary.wiley.com/doi/pdf/10.1111/vec.12881.
- Nice discussion on DOCP from a pharmacology perspective: https://todaysveterinarypractice.com/pharmacology/desoxycorticosterone-pivalate-for-dogs-with-addisons-disease/
- Critical Care Chapter on Sodium: Click Here
What do you recommend if the hypernatremia is above measurable levels on lab work? How do you calculate an appropriate correction of the electrolytes?
- Step 1 – see if we can identify if these changes are chronic or acute
- Step 2 – I usually call in a critical care friend due to the sensitive nature: https://www.criticalconsultsdvm.com/our-team
For hypothyroid vestibular, how long after resolution of clinical signs do you wean off Thyrosyn? How long of a “weaning course” do you recommend?
- I usually let them be normal for around a month, then wean them off over a week or so. I use this paper to help me make my decisions; they appear to withdraw them a little quicker, but if I see a relapse with a wean, then my answer is there. This paper suggests that you can test your thyroid around 1 week after stopping therapy. (should be open access) https://pmc.ncbi.nlm.nih.gov/articles/PMC5435074/
How do you clinically differentiate FCE from feline ischemic myelopathy when clients are unable to afford advanced diagnostics?
- I don’t think you can outside of, if it’s a cat, I’m going to assume FIM if it is more in the cervical region. Realistically, some FIMs are going to be due to FCE. They will both be treated the same way; FIM may warrant looking for other underlying causes.
Do spinal migrans of heartworm(s) present with progressive clinical signs?
- The ones reported tend to wax and wane over time, perhaps with some progression. They are fine, then experience a period of discomfort, then are okay, and then become painful again. They appear to become painful if the worm moves or if it is large and causes stretching of the structures in the neck, leading to acute pain signs.
