Aug. 9, 2023

#98: Spirocerca Lupi: Unmasking The New Hidden Challenge for Australian Vets. With Professor Peter Irwin and Dr Gillian Tenni.

#98: Spirocerca Lupi: Unmasking The New Hidden Challenge for Australian Vets. With Professor Peter Irwin and Dr Gillian Tenni.
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Season 1

Vets of Australia, meet Spirocerca lupi, a parasite that's been flying under the radar for a while now in Northwest Queensland. But as you'll learn in this episode, is well worth adding to your DD list. To make the introductions we're joined by Professor Peter Irwin, an Emeritus Professor from Murdoch University with a career that spans several continents and almost four-decades. He's a registered specialist in canine medicine with a particular passion and extensive knowledge on anything and everything vector-borne disease.

Our second guest is Dr Gillian Tenni, a passionate GP vet and practice owner from Mount Isa, Australia. Dr Gillian holds an Honours in Parasitology and has a knack for spotting unusual infections in her patients, and with a track record of more than 300 diagnosed cases of Spirocerca lupi, she's our 'boots on the ground'. She's also teamed up with the University of Queensland for a research project on Spirocerca lupi.

Join us for the full Spirocerca story, from what it is (creepy), how it spreads (gross), what it does to our patients (scary!), what to look out for, diagnosis, some tips on treatment, and of course, prevention. Prof. Irwin's wisdom and Dr Tenni's hands-on stories provide us with some real insight on the fascinating parasite and the condition in causes.

This episode is supported by Elanco Australia. You can learn more about their range of products at elanco.com.au.

 

Topic list:

03:22 Spirocerca Lupi... yes, it's a thing in Australia.

06:52 How does Spirocerca Lupi spread?

09:41 What's the life cycle of the disease in a dog?

12:52 The clinical signs of a Spirocerca infected patient.

19:51 Dung beetles and where Spirocerca is most common in Australia.

22:14 More on the presentation of Spirocerca and the challenges of diagnosis.

34:20 Treatment.

38:10 Add-ons to the typical treatment plan.

41:08 Cross-reactivity in heartworm antigen tests of Spirocerca.

 

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Quick spoiler alert, I'm going to give away one of the key takeaways from this episode.Now, as you'll hear, surprise Spyro Circa is a thing in Australia.Depending on where you are.I feel like we're in a bit of a habit on you talking about weird parasites that have made their way from a country of birth to Australia.
I just want to be clear that there is no link between my migration to Australia and the appearance of these exotic new diseases, just in case any rumors start appearing that I'm importing stuff just so I can get exciting new content for the podcast.It's not a bad idea, actually.Anyway, so in this episode we'll cover what the heck Spyrocirca is, what it does, how we'll spot it, and what to do about it.
And one of the things that you'll learn that we'll put right here at the front end is that it can be effectively prevented with something that you probably already have on your shelves.Advocate, Our Old Faithful Advocate is the only registered product for preventing Spyrocirca.Loopy, and the team at Ilanco Australia, the makers of Advocate, Credilio Plus, Cerrestro, Milbumax, NPTRA, and Galliprandt to name a few, are paying me for underlining that fact.
So consider that the sponsor's log done for this episode, and thank you Ilanco for your support.You can learn more about their range on their website at ilanco.com dot au okay.Now let's get to everything you need to know about this weird, very interesting, and a little bit scary condition.
Inspirosycalupi with Professor Peter Irwin and Doctor Gillian Tenney.Peter Irwin is an emeritus professor at Murdoch University with a career spanning nearly 40 years, working in many fields of veterinary science, including teaching many of you at uni.He's a registered specialist in canine medicine, with a particular passion and extensive knowledge on anything and everything Vector borne.
Basically, if you want to know anything about any disease that spends some part of its life cycle inside a bug of some description, he's your man.Doctor Gillian Tenney is a GP vet and practice owner from Mount Isa in Australia who keeps finding unusual infections in her patients and helping us to learn more about them.
Doctor Gillian has an honors in parasitology and is diagnosed over 300 cases of spiracerca loopy in her clinic.She's also involved in a research project about this with the University of Queensland.So she is the boots on the ground for us and she shares her wide experiences with this condition with us.
Please enjoy Professor Peter Irwin and Dr. Gillian Tenney and Spider Circa Loopy.Welcome to the Vet Vault and thank you so much for joining us.And we have Professor Peter Irwin, The Tick and other Bug man.We've had him before talking about aliosis, the vector borne diseases professional and we're going to talk about it.
A newbie to a lot of people.Not that new to me because of my South African background, but new to most of us.Spider circa Loopy.Now firstly, quick introduction, Jillian, just so listeners know internal, I get an idea where you're from and well, you're in Mount Isa.
A lot of people don't know where Mount Isa is in Australia, so vaguely roughly speaking, just so people can go, How far away is this stuff happening?From where I live?Where in Australia is Mount Isa?In Northwest.Queensland, inland from Townsville but closer to the NT, so OK so quite far in inland so far.
No long way to walk, long way to walk.OK, long way to walk for a tick that's infected with some weird sort of parasite.So, Jillian, I had no idea that Spyra Circa was a thing in Australia.Again, I went to uni and in South Africa and we had Spyra circa there relatively commonly and I can remember very little about the details.
I remember something about the growth in the Thorax somewhere and then they get weird things on their legs if they have it really badly.That's about the gist of my knowledge, but I had no idea that it was in Australia.Tell me what you're seeing in Mount Isa.You've picked it up in a few cases.
How many cases?It gives a bit of a rundown of what's happening where you are.Well I have to credit Doctor Lane Fulham for he was the first person to diagnose it in Mount Eiser and he said he diagnosed it first in the mid 90s so he picked it up in a pigging dog.
So the arena was bringing down beetles into his yard, collecting them I think to help with getting rid of the stools.And a few of his dogs were thick and died, so like decided to.Postmortem to find out what was going on and that's when he first diagnosed spirocerica.
He had heard of it and read about it, a few cases.I think in the NT it was still I think quite right there.And since then it's been on a radar and I started in 2014 and we would see maybe 3-4 cases every year of dogs with clinical signs.
And then I had one dog that developed neurological signs is really sick and and died.And then since then I decided to just endoscope dogs coming in to the clinic with the owner's permission for just routine surgeries.
And I found there are a lot more cases that I just I most cases actually I think are asymptomatic.Or the signs are mild and not something that the owners thought was abnormal, say just occasional vomiting.
So how many cases are we talking in, in a in a how long a period?How many cases have you diagnosed clinical or subclinical?Well, it's lost count because they've been a bit busy and it's I need to get on to that again.But I'll be over 300 cases that we see Mad eyes.
Wow.OK, wow, so Peter and what what's the what's the official stats?Is it is Mount Isa the home of the spider circa?Or is it just that Mount Isa has a vet that's looking for it?Well, I I think, I think Mount Isa is probably the epicenter of Sparra circa in Australia, just to sort of go back with with a little bit of my background too.
I saw a case in the early 2000s, 2001, 2002, something like that of Murdoch over in Perth.And that case it come from Mount Isa.So you know, it's been in Mount Isa for a while, but it's not the only place in northern Australia that the parasite exists.
The very first report, I believe of Spira Circa in Australia was in northern NSW and then cases have been reported in other parts of Queensland, Bamaga, right up at the top of Cape York and a crossover in Cananarra, WA.Certainly, you know, Mount Isa cases have been diagnosed for quite a long time in Mount Isa.
As Julian says, it's.Really common.And the work that Gillian is doing in raising awareness and finding these cases is extraordinary.It's fantastic.OK.So give us the idiot's guide to spar a circle, Peter.What is it?What spreads it?
How do our patients get it?Yeah.Give us start at the very beginning.Well, I'll give you the idiot's guide, and then Gillian can fill in the gaps.OK, cool.So it's a nematode parasite.It's a it's a worm.Roundworm.That is associated with dung beetles, and it affects not only domestic dogs but actually some wild canids as well.
The dog becomes infected when it eats either the dung beetle or more commonly A paratenic host.And just to sort of remind everybody about their parastology, paratenic host is another animal which has eaten a dung beetle, so things like chokes, for example.
Rodents or reptiles, lizards and things that might have eaten a tongue beetle, the parasite.The infective larvae that were in the dung beetle then gets into those Paratanic coasts, but it doesn't go any further in them.Okay.So dogs, dogs can become infected from eating, as I say, either the beetle or any of those other organisms.
So red eats dung beetle.Dog eats red.Yeah, exactly.Or Chuck.Or whatever.It'll be interesting to know whether Gillian.Has any observations on this?Well, we could ask her, shall we now or Yeah.So what are you finding?
Are you getting a feeling for how it is getting into your patients up that way?The eating tartile isn't, so that would be the main.We have a lot of lizards here, so I suspect that that's one of the first things we ask.
And yeah, look, most often dogs that have an infection, yeah, lizard eaters.The tartar lizards.I have also diagnosed it in Labradors that like to eat their own stools, so that's another.So they must be just eating the dumbbell straight, but I think it's mostly getting lizards or sometimes.
Birds, I think from when I've spoken to clients, okay.So it'll be your.I'm expecting that you're seeing it more in your hunting kind of dogs, your terriers and the things that go out and see, well, that's moving.I'm gonna eat it.Sort of a dog cuz I don't picture my chilled poodle crust.
You won't eat anything if it's not cooked.You can actually get I can get inspired soca.I have definitely seen it in Little Yeah, that I always thought that, yeah, we mostly see it in terriers, but I have also seen it in massive great Danes, Mass bull massives that you think would be too slow to leave and capitalism.
But we do surprisingly see it.Little fluffy poodles and things too.But most commonly, anteriors and Stafford Chital tarries the ones that like to chase.So beat it back to you then.So dog eats infected Organism and then what happens?
What's the life cycle in the dog?Yep.So then it gets really interesting and the the larvae get into the gastric mucosa, into the stomach mucosa and then they migrate up the gastric arteries, up the walls of the gastric arteries to the aorta and their first, their first.
Goal, if you like, is to get to the aorta, and they do this, as I say, by migrating through the walls of the vessels to the aorta where they settle in for a little while for a few months.So it takes them.Various studies suggest different amounts of time, but relatively short time to get to the aorta, maybe a couple of weeks, something like that.
They're going upstream up.Yeah, well, they're in the wall of the vessel, so they're not fighting against the.So once they're in the aorta adjacent to the esophagus, they sit there for a while.They do quite a bit of damage to the aorta and we'll come back to that later.
And once they've been there a month or two, they then migrate on into the esophagus, which is adjacent of course, within the media stylum.Once they're in the esophagus, they complete their life stage.The males and the females have developed by then.
And the males and females do what males and females do.And then the females will produce eggs and they create nodules within the esophagus with a hole in it.And the female worms can be seen.And I think Julian has seen the female worms sort of sticking their posterior out through the hole, and they lay their eggs into the lumen of the esophagus.
So then they're swallowed by the dog.They make their way.Right the way through the intestine of the dog and out in the feces as embryonated eggs.So the female worms ladies embryonated eggs and out they go and then the life cycle is completed from the feces.
The dung beetles of course will go for all sorts of poo and they then get infected when they eat, ingest the embryonated eggs there.So they're spending their time either in the in the blood vessel walls and then they move across and then they're gonna live in the savageal wall as well.
So they're not luminal, they're sitting in the live in the in the connective tissue of the wall.Yes, yes, that's right.That's right.And I guess the pathology, which we'll talk about in a minute, but the the clinical signs of the pathology is all associated with either the migratory stages because sometimes like other parasites that could be aberrant migration and the larvae can go to all sorts of places that they don't intend to go.
Can lead to clinical science bit neurological or whatever or the sort of second group of clinical science mainly are associated with the esophageal lesions.OK, well, so Jillian, beyond when you scope dogs to go looking, so you're obviously scoping the esophagus and then you go, I can see nodules and I can see womb butts poking out into the intestinal tract.
What are you seeing them come in like clinically, what are we looking out for?So the main presentation is trouble swallowing in evidence and regurgitating, vomiting, sometimes coughing.So they're the main things.
We see other signs and what Peter said, our neurological signs have had a few dogs with neurological signs, hypersalivation, really drooling.Not all dogs have that, though.And and then some cases dogs will have parasis in their hind legs or sometimes a front leg.
And then other times I've had dogs just die on presentation from an aortic aneurysm.So that's they've had no signs whatsoever and they've come in and died not long after being in the clinic and then we found that they've.
Had a bleed and then when we've done the postmortem, found the nodules and their esophagus.Yeah, most of the time it's the difficulty.Swallowing, regurgitating.They're the main signs we see okay.So you've got a Mass Effect of some sort.
Is is it a physical Mass Effect or is it a stricture of the esophagus or or what's the pathology that you start seeing in the in the esophagus when you scope them?Is it physically just a big nodule full?Of yeah.It's mostly an A Mass Effect in the esophagus, but sometimes they will only have a small nodule that they'll be have quite marked clinical signs.
They must just cause a bit of esophagitis as well.But I think the nodules can become infected.Is that right, Peter?Yep, that's right, Joan.They're quite often surrounded by my pus and I don't know if you've done any postmortems on these or maybe when you cut into them or whatever, you know, you get this pus comes out of them.
So you know, histologically they're sort of pus filled nodule as well with lots of lymphocytes, lots of neutrophils, yes, So.So antibiotics might actually play a bit of a role in managing some of that local infection and the neuro signs that you talked about.
So hind limb or spinal or anything, again that's aberrant Laval migration where instead of going along the vessel wall, it gets to the spinal cord or so they can go anywhere.Yep, Yep, that's right.So they get into the spine, as you say, into the spinal cord, they cause hemorrhage, and then this is a sort of cervicothoracic myelopathy.
So I guess they look like a.Like a disc.Some other transsectional type lesion in the thoracic, usually in the thoracic spinal cord.Yeah, so off the hind legs.Front legs might may be fine I guess upper motor neuron type signs to the hind limbs, but but anyway, paresis and paralysis is Julian as Julian says.
The other thing that is perhaps useful diagnostically, I'd be interested to to know what Julian's experience with this is, but.But some of those larvae that are migrating on their way to the spine cause a periosteal reaction around the thoracic vertebrae mid thoracic to cordal thoracic vertebrae and you see those exostosis on the bones.
And you know, it's not a specific diagnosis, but again, in a dog we'll come to diagnosis in a minute and how difficult it can be sometimes.But that's something that is well reported in the literature.I've not actually seen that in any of relatively few cases I've treated here in Australia.
But Joy, is that something that you recognize if you take thoracic radiographs?Yeah, definitely.See, sometimes you can see the esophageal nodule in the X-ray, but often.You don't, but I on the X-ray I was finding a pattern with the ventral spondylitis.
So you could see those changes on the cordal thoracic vertebrae.I one of the young dogs I had a nine month old Labrador.She had neurological signs.Is really terrible vocalizing.We thought she had steroid responsive meningitis, arteritis for ages because she was responding to steroids, but we found that she had spira circa.
Unfortunately, she died.And then when we did it, I did a postmortem.You could see all those changes on the vertebrae, but also coming down onto the ribs I think as well.I've never seen it before.I remember back from South Africa, you get this weird thing.
It's called Mari's disease or something, where they get distal limb Bony changes to do with the intrathoracic mass.Yeah, well, I can't.Yeah, that's all I remember.What's the goal with that?What causes it and what does it look like clinically?Well, yeah, that's what you're describing is hypertrophic osteopathy.
Which is Mary's disease, as you correctly remember from your undergraduate days.And yeah, that's as you said, it's when there's a periosteal proliferation in the distal limbs, particularly the carpal bones, metacarpals, distal radius, ulna, and also to some extent in the hind legs get a lot of periostal reaction and lameness.
So it's painful.It's painful.And so lameness is a sign of that.It's associated with these lesions and the esophagus.And what we haven't talked about yet is the preponderance of these nodules to become cancerous.I'll talk about that in a minute.
But so they'll.I understand that they will occur with just the nodules, but certainly also when it's turned near plastic.Julian, do you see lame dogs as well?I haven't seen any dogs with that hypertracy cost you this ill the Mary's Mary's disease, but we do.
You see a lot of dogs with boring cancers, but I'm not sure if that is.Are you saying that the cancer, boring cancers and other cancers may be linked to this virus arc?Sorry.Is that what you?No, no, sorry, sorry for any confusion.No.The nodules in the esophagus, about 1/4 of them, at least according to the literature, about 1/4 of.
Dogs with nodules in the esophagus become cancerous, so they they turn into sarcomas, and a number of different types of sarcoma have have been reported.But it's just the presence of the lesion within the thoracic cavity that leads through mechanisms, I think that are probably not terribly well understood to these periosteal proliferations in the distal limbs.
So you know this you can see.Hypertrophic osteopathy and animals with lung cancer as well.Quite unrelated as well.I don't.I haven't really seen those brain changes in the limbs.I have seen a couple of, like you said, the cancers in the esophagus.
So these are all very frightening things that I feel like people are listening, going, oh shit, that's something I've got to keep an ear out for.But let's talk about dung beetles first.Do we have endemic dung beetles in Australia?And if so, where do we get them?Basically?Do I have to worry about them where we live it?
Was a wonderful story behind this.There are native dung beetles in Australia, but the native dung beetles evolved here to push away macropod.You know marsupial poo.That marsupial poo pushes.
And then, you know, a couple of 100 years ago cattle and horses arrived and then the native dung beetles are not capable of dealing with introduced species who so in the 1960s, and it's as recently as this, the 1960s, there was something called the Australian dung beetle project and this involved the importation of bringing in.
Of a whole range of species of dung beetle.Actually 43 different species of dung beetle.I can hardly believe that.But anyway, different different species and liberally sort of plastering them all over the Australian landscape.Not so much to deal with the aesthetics of lots of poo in the fields.
Because apparently you know, if you you go back and you read about how things were, you know, poo would pile up in in paddocks.And that wouldn't be very nice, but it was the associated fly problem.That really worried people.So CSIRO oversaw the importation of all these dung beetles.
Prior to that, there had never been a case of Sparrow, circular loopy.But within a few years of all this happening, the first case was was diagnosed.So I guess to answer your question, all the dung beetles were brought in and I guess it's assumed that some of those dung beetles probably from South Africa, other places you know, brought with them Sparrow, Circular, loopy.
So you brought the South Africans in to come and clean up all the shit, but then.But then they came with their own problem.Wow.OK.So are they widely distributed throughout the country or is it regional climatic or?Well, I understand now there are dung beetles everywhere in Australia in terms of cases of spira circa.
As we said earlier on, most of the cases have been reported from the northern parts of Australia.So tropics and subtropics.But but you know.As listeners, we'll appreciate from the discussion that we're having, this could be a really challenging diagnosis, whereas there may be some very specific aspects to it.
Like if you put a scope down and you see nodules, you know, there are not many things that cause nodules in the esophagus.But I would imagine there are cases of spiral sarcosis happening around the country that may go unrecognized.Yeah, sudden death and.
Yep, some death bleeding out like this.You know, the odd lame dog and then, you know, regurgitating and vomiting dogs.They're always a bit challenging, aren't they, in practice?And they might be put down to an idiopathic negroesophagus, You know, something like that, especially if they're not scoped.
I'd be really interested to hear your perspective on this.This too, Julie, and just the sort of the challenge of diagnosis and we could talk about some specific tests in a moment before Jillian tells us more about diagnosis, treatment and importantly prevention of Spira Circa.
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OK, back to Dr. Gillian.Yes, I think they can.I had one dog that I thought had a massive tumor in its lungs and it turned out to be Spiro.So I've had dogs that have, you know, it's definitely Spiro circle and the dogs had a foreign body or vice so.
So it's just really, yeah, hard because there are so many different signs and dogs can present differently.It can be challenging to diagnose, so let's talk about specifics.So we talk about.So hey, it sounds like it's gotta be on your radar because we're gonna confuse it for a bunch of things and look like something else.
And if it's not on your radar at all, you might just miss it as a diagnosis.Does that sound fair?Yeah.So GI sign Well, upper GI it's softer GL signs and.Some of the cases I've seen vomit as well.You know how we're always taught to differentiate regurgitation from vomiting, but I have seen dogs that really seem to be doing a bit of both with this.
So and then there's this hyper salivation and this weird salivary gland enlargement that is quite well reported.I actually probably see some of those cases as well.You know, with profuse salivation and discomfort on swallowing.
So you know, here's a picture of a dog with esophageal disease, yes, but in addition to that then it has to be on a differential diagnosis list for as you said, sudden death, you know, leading into the chest.The main differential would be rodenticide toxicity or something like that, Lamenesses and then these neuro signs.
So dogs with paresis hindlin paresis paraparesis.And or paraplegia, OK.Would you agree with that as a a summary?Yes, definitely.I've had dogs that a dog went to a specialist because it was paralyzed in its back leg and it was put down to a blood clot from its heart.
And then it wasn't until, I think a couple of months later, it came back, it was vomiting and just scraped that dog and it had spiracy occur and that, yeah, so it was.Probably.Maybe a blood clot from I'm not sure if the parasite can cause blood clots, but once we started trading this virus, circus is it the dog improved.
Like you said, it can cause such a wide variety of clinical signs and lots of different presentations.So do we have an easy test like a PCR or Eliza or something?Or do you have to literally scope them to go see the nodules there?
No simple test.I'll start off and then you can set the record straight.So I guess there are probably 3 main modalities for diagnosis.One is imaging, imaging the thorax.And we've talked a little bit about the fact that you might see radio opacity suggesting a lesion of the esophagus.
But you know, sometimes it's difficult to differentiate that from a lung lesion.We talked about the Spondylosis on the thoracic vertebrae.So there may be some clues from a thoracic radiographs CT If you have a CT in the backroom, then there's the fecal testing.
Remember these female parasites, female worms are spitting out eggs, embryonated eggs.The good thing about this is that the eggs are very distinctive.I don't think there's really any other.Parasite eggs that look like them, they they're sort of, I think they described them as being bullet shaped and you can see the little lava inside them, the embryonated lava inside them.
So that's the good thing.The bad thing is, of course the females don't shed the eggs all the time and so it's intermittent and so any given fecal exam on a on any given day might not reveal them.So that's the second thing.And then?Probably the best diagnostic test is what Gillian's doing and that's to scope them.
But of course in the real world you happen to be in Mount Isa and have an interest.You know you're not going to be scoping your patients.But in terms of, you know, a visual hit and diagnosis, endoscopy is the way to go.We might talk about the heart worm test in a minute, Gillian, if you like, but do you want to have any further comments on what I've just said?
No, I I'm just found it easier to end scope them.But like yeah like you said I found it hard in the past to diagnose cases on a fecal float.I think you need a special medium and also like you said they're not shedding all of the time.
It's a much easier for us to diagnose and by endoscope.OK, so if you think it's by a circle you scoping them, How about the aberrant 1?So let's say I've got a neuros case and now I've got another parasite.
I've got to rule it out for my for my gme case or my steroid responsive.Would it ever be a case where it's not actually in the esophagus yet?So it's gone up the blood vessels and now it's in the nervous system somewhere, but it's not going to be there to see when I scope it.
What do you think about that, Julie?I mean, theoretically of course, as lava can be causing spinal cord lesions before other larvae have got to the esophagus.I get the impression from reading and talking to people with these cases is that usually there are already some esophageal nodules when some of these other things occur, and certainly.
The cancerous type changes, they occur later, I think dogs with acute aortic aneurysm and lead to death.You know, they might not have any nodules, but yeah, I'm interested to hear what Julian says in terms of chronology.Yeah, I'm not sure about that either.
The dogs that have had neurological signs that I've and just scraped that I suspect do as far as I could have had nodules and they've been quite large nodules.So it's been clear cut, but it's I guess it's possible.But I should say that also I've found far more dogs have no signs whatsoever.
So we have found out most of their cases the dogs were are asymptomatic too.So they have, they don't really have signs.We're picking them up just when they are having routine surgeries at the clinic just with the owner's permission, we're endoscoping cases.
So some dogs will have.Massive nodules and no signs at all.Wow.So that's that's a reflection of your unique situation there, isn't it really, Gillian, I mean it's it's very instructive.But you know, one assumes that all those dogs that are asymptomatic when you have spaying them or something in a year or two or whatever might go on to develop science or do you think there really is a?
There are a lot of subclinical cases that never do advance to all this exciting pathology we're talking about.I think a lot of dogs don't progress.That's just my opinion.A lot of clients do like us to do the routine screening.So we do do them at six months or whenever they're D sex.
And I've had quite a few cases that have been negative on that skin.And then they've they've come back a year later unwell and we've scraped them and they've got the clear nodules.So there's certainly dogs that are unwell.But a lot of the cases that I've seen are older dogs and the nodules, they've got quite a few nodules and then some scarring where you can see there was a nodule, but that's cleared up and then there's a new modules formed somewhere else and they haven't during signs of whether or not it's the iron is that have not noticed.
I don't think they all progress to have some of the severe signs I have seen in other cases so.Am I right in saying that you're also involved in a research project on this?Is that?One of the other reasons why you would scope them again later when they're asymptomatic.
Oh yes, sorry.So we are because I was I had a spade of dogs a couple of years ago.We might have had five or six dogs just die within a short period of each other and they would all diagnosed have spiraser and it had me a bit worried and and then I contacted.
The University of Queensland, so we are doing a study with them and I think the plan is to send blood away so that hopefully a blood test may be able to be developed that will help in the diagnosis.So that would acacance that would be good for those cases.
If there is an esophageal nodial present but the immature stages causing a problem then that would be picked up that way.Or if the dog's too unwell to be and just scoped.Or any tires.I'm trying to figure out what to take away from this as a clinician because I've never seen it in Australia, but maybe I've missed it.
I'm not going to be scoping.Is it regional?Is it because there's obviously a hot spot there, like working in Brisbane or in Perth or something like that, you're not going to start scoping looking for a disease that you've never really seen before?I I I think you should actually.
You reckon I?Think that's the way to to pick them up.But, but I'm speaking with a sort of research.Yeah.You know not not a very practical you know the the one that worries me most almost because I go yeah, if you come to me with upper GI signs at I'm going to X-ray you and there's the next step we'll probably scope you.
So you're going to find it if that's the if it's the main presenting thing.The Nero's 1 freaks me out because you go, all right let's send off the PCR.And our Elias is for Neo and Toxo and WADA WADA, we do all of that.Would you see parasites on a CSF tap if you're tapping them or not necessarily?
No, no, I think you wouldn't see the parasites, but you'd see inflammation.So, so these dogs have inflammatory final disease and then you go, yeah, it's got to see.Generally, well, no.It's generally eosinophilic.So you know over here on the East Coast of Australia, you know, we always think of and just stronger as the cause of eosinophilic meningitis or Meningo.
And kefalomyelitis.But so this is another differential.It's eosinophilic.It's a parasite, so that's the next question then.So that's diagnosing the sick one in terms of preventing it.So if it's a worm, do your standard antialmantics kill it before it starts migrating to all of these nasty places?
Yeah.OK.Well, I'll start off that that answer and maybe Julian can follow.So most routine antiwormers really have very limited efficacy at.Preventing this, the drug that has been shown to be most efficacious is an avomectin.
So moxidactin and the drug or the preparation that is actually now registered in Australia to prevent spiracycular loopy, is advocate.Okay, okay.So they previously bad the Alanko product and the early work was done in South Africa and in Europe at South Africa and Reunion Island of all places.
And then more recently it's got a registration claim to prevent Sparrow circuit.So dogs or pups put onto advocate from a young age, it's very, very efficacious of preventing it.Has much better activity than something like normalizing, for example.
OK, Jillian, what are you guys recommending to your clients?Do you get tick paralysis?Did you get paralysis ticking round Isa?No, we don't have paralysis ticks at here which is excellent just thankfully we yes we recommend advocate for prevention and I we haven't seen as many cases recently and I think it is all down to using advocate now because that's we recommend.
Puppies come in for their vaccinations, so they start off on that.But for dogs that also do have the esophageal nodules, we use advocate as treatment.So you see advocate as a puppy to prevent the parasite, but then the treatment also is advocate.
Once a week for 12 weeks and then we repeat the end of scrape at 12 weeks and if the nodule has resolved then they go on to the monthly prevention.We did use Ivanectin in the past but it was a bit difficult for in it, so we used it or they we prescribed it orally but it was harder for.
Trainers to use and yeah, that we recommend to The Advocate.So that's a lot easier for clients to use as well, and safer I think.Yeah, I mean, I guess strictly, I mean all of this is off label, but as you say, there's a lot of data to support advocates in that way once a week for 12 weeks spot on.
So you know the monthly dose every week for 12 weeks to treat A.Treat this is for treatment.Yeah, we used to use Ivermectin.There are risks associated with that as well of course.And then Doramectin, which is Dektomax, isn't it.Doramectin has been used.
It's a large animal product and some of the papers that have been published would suggest that Doramectin in in advanced cases or cases with significant esophageal disease.The Doramectin may may be better than advocate but but in general the recommendation is Advocate.
And then, Jillian, do you, if the lesions are still there, do you just keep going with the advocate?Yeah, I've had a few cases where I've had to continue a little bit longer, maybe another month or two.Sometimes it can be a bit tricky because they look resolved, but then there is some scar tissue and it's hard to really tell, but generally you do.
For those cases, you do see a significant improvement within the 12 weeks and the nodule has cleared up.There may be just a bit of like an.I don't know if it's scar tissue from the periculum, but generally yes, 12 weeks is all they usually require.
Do you add anything else into this treatment plan?I mean, do you do you use an antimicrobial in any way?This is a leading question, but I I just wondered if you.You do.I do, yes.So for dogs that show clinical signs and sometimes there's quite a lot of bleeding from the the nodule.
So I'll often put them on amoxicillin, clavulanic acid.And then I'll also find a lot of the dogs are really that are really unwell, don't want to eat, they're gagging, they're really uncomfortable.So sometimes I also put them on Prednisolone as well.And I find that they respond quite quickly to steroids and I think must Bridget, help reduce the inflammation in their esophagus and and sometimes I'll put them on carafate as well.
These are the dogs that are really unwell and sometimes I need to be in hospital for a few days and not eating.But yes, I do use an antimicrobial and steroids often in symptomatic cases.Yeah, who might choose to cut this bit out?But just two other.
Comments.First of all, just interestingly, the the spirocycle loopy worm.They've now shown this, a symbiont bacterium associated with, you know, the whole story, with heartworm of course, and treating with doxycycline as part of of the heartworm treatment protocol.
And the doxycycline kills this, the symbiont, which further weakens and kills the heartworm.Well, as I say, this particular bacterium, it's not fall back yet it's a different.Bacterium that is associated with spiral circa and I'm looking out for studies or hoping somebody's going to look into this as to whether advocate with an antibiotic perhaps might be even more effective.
Why would I cut that out?Well, I don't know.Responsible antibiotic use?You will, possibly, but the other thing was this weird thing about the salivary gland abnormalities and being phenobarbital.Responsive and I have used Fina Barber for some of these cases in the past to try and control the excess salivation and the discomfort and all that type of thing.
And I wondered if you'd been down that tricky pathway as well or not.Julia.Oh.I have it, but I do recall the previous owner of the clinic when I remember him using if they developed for treating hyper salivation as well and I haven't used it myself so.
I don't see that many cases of dogs with saliva gland pathology, but every now and again we do see some.Yeah, I think that in its own right can be very distressing for the dog and very distressing for the owners.And so it is something to consider and there's published literature about its efficacy, which varies greatly from dog to dog.
But nevertheless, it's something to have in the Armory, so there's nothing like with heart to him, where you have to be careful how fast you kill the parasite, or where they suddenly are going to shade into the aorta and cause a thrombus or something.You just kill the buggers.Get rid of them.
Just perhaps while we're talking about half worm, this is another just important thing about sparous circa and that is the cross reactivity in the heartworm antigen tests of sparous circa.So in the studies that have been done up to 1/4.
Of heartworm positive cases as far as circa and not heartworm.So if you live in a heartworm endemic area and you routinely are using heartworm antigen test, then this is just something else to bear in mind.
And Julie and I would be very interested to know if you have a take on this from your perspective.Yeah, I I definitely have seen cases, but it's hard because we also do see heart worm here as well.But when we do get a positive heart worm like antigen test, we always look for the micro flare as well just to be sure.
And then if that's negative then I do recommend and scoping them.But it also becomes challenging when a dog has both heart worm and spar a circa in terms of treatment.I'm still a bit stuck with the prevention strategy if you are in a paralysis tick area in Australia because then you want to be on a nasoxazolin or something specific, but that's not going to do anything for your spiracerca basically just confirmed about concern about MiTo.
Yeah, well, some of the asoxazolins also have no novomycin in them, for example.But, but novomycin's not a particularly good preventative for Spiracerca, so you'd need to.You'd need to use the two I think.So if you if it's if we start seeing those sort of cases, then then you've got to have both all go region dependent.
Go here which might which is my biggest risk, the tick or the spiner circle.OK, that's fascinating and a little bit scary.Interesting, but good to know about.Are we missing anything Peter?Have I missed anything important in my ignorance?Well, we seem to have covered a lot of ground.
No, I think from my perspective, we've talked about all the.Important clinical diagnostic and sort of preventative therapeutic aspects, yeah.Jillian, am I missing anything?No, I don't think so.I think Peter did that.Very good job of explaining everything in this.
You bloody hope so.That's.What you paid me for, Jillian.Thank you so, so much for for making the time and for your ongoing curiosity and finding these cool things and being happy to share with us.I really appreciate your time.
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Professor Peter Irwin

Dr Gillian Tenni