Hyperthyroidism

[DeltaCharlie]

Turning to the DOL Brain Trust here as we have a bit of a medical mystery. I don't have all the blood results so will ask my friend for them if need be, the dog isn't one of mine.

Background:

11 year neutered male border collie who has always been about 15kg. Struggled on and off to keep weight on him, pretty much his whole life, but it has been pretty stable for the last few years. About Nov of last year he got really thin again almost overnight. Required about 3x as much food (raw diet) each day just to stop the weight loss but no real weight gain. He was down to 12.8kg. Due to issues with his toes he doesn't free run, rarely goes for walks and pretty much lazes around the house. So no chance of burning off 3x as much food through exercise. I suspect muscle loss from 12months of reduced activity has contributed somewhat to the lower kg, but you could easily feel spine, hips, all the ribs etc.

Around the same time his thirst increased remarkably and he was drinking and urinating often. He has never coped well with warmer weather so at first it was put down to the heat. Urine was concentrated appropriately. He had started to breath much heavier but no coughing, which was also put down to heat initially.

During January he went to the beach, was carried over the sand and allowed to swim, then carried back to the car. Unfortunately this was enough to aggravate the toes and he ended up with hot spots on his feet from licking, and later hot spots up the leg.

He has never been a dog that has loved other dogs in his space, but he had become increasingly grumpy even with familiar dogs.

Medical Stuff:

In January he went in to his previous vet on a visit to Canberra as the symptoms were getting worse and my friend was concerned about the water intake and possible kidney issues. Vet detected a rather loud heart murmur (that hadn't been there a few months earlier) and his heart rate was higher (120, so in normal ranges but particularly high for this dog). She took bloods to run a biochemisty panel and to check for something cardio (not 100% sure what that test was). She also gave some dimethyl phthlate to stop the licking of his feet.

The biggest problem that showed in the blood work was that he had a t4 level of 145! (normal range is 21-51). Kidneys were fine, liver was a little abnormal though. To ensure that it wasn't an anomaly she had the regular vet do an inhouse test for t4 (range 1-4) and he came back as >8. Thyroid glands were palpated but nothing could be felt.

Given that hyperthyroidism is so rare in dogs to begin with, most cases seem to be due to cancer or nodules on the thyroid gland. So he was referred to the ARH in Sydney for an ultrasound of his thyroid gland. Nothing abnormal showed up on ultrasound or chest x-rays.

He also had an echo done to check his heart murmur. They discovered that his mitral valve was inflammed and that is where the leak was. Apparently this is not what they were expecting though. They were looking for similar issues to what hyperthyroid cats get but he was completely different, so the specialist questioned whether it was even related to the high thyroid or a completely different issue. He had no fever so they didn't think it was worth trying to grow any cultures to look for a cause for the inflammed valve at that point in time, instead they asked for a CBC, biochemisty, urinalysis to be done at the regular vet. They are also going to try to grow something from the urine. Those results should start coming through today. If infection is indicated he will go onto antibiotics to try and reduce the inflammation in his heart.

Where to from here?

The vet is questioning something environmental as the trigger. There are 2 younger dogs with hypothyroidism so she finds it a little odd that there are 3 in the same household with thyroid issues (although a further 2 dogs have tested as perfectly normal thyroid). The thyroxine supplement is kept in the fridge so he has no access to it and he rarely interacts with the other 2 dogs so highly doubt he has been supplementing himself. They did share a toileting area so he has been removed from that area entirely in case he has been getting thyroxine through urine/faeces of the other 2. He isn't one to eat poo, but if he stepped in some he is a fastidious cleaner. Highly unlikely as he would need to be doing a lot of it and regularly to reach those levels but easy enough to toilet him elsewhere and remove the opportunity altogether. He very rarely leaves the property.

It is a rental house so not 100% sure of any chemicals used previously, moved in in May. The owner said he used neem oil and a bit of derris dust near the fruit trees (which are nowhere near the dog area). Some of the other dogs would have much higher access to these areas but they are all fine. Inside the house no chemicals are used on cupboards etc as this dog likes to lick doors and floors.

After communications with Jean Dodds she has recommended removing all raw, red meat from his diet and retesting in 4-6 weeks. The specialist had also suggested a diet change to a commercial food with no added kelp or iodine supplements, so a bit of research has been done into that and taste of the wild will be trialed, along with chicken/turkey mince.

He has been taken off the dimethyl phthlate and will look into some bitter apple to deter him from licking his toes.

There is also a scintigraphy that can be done to check for any abnormal tissue in the neck region, but the specialist didn't think it was worth doing at this point in time.

Ideas?

The vets are all at a bit of a loss at this point in time. Not only is it rare to see hyperthyroidism in dogs, its even rarer to have no obvious cause. The main questions we need to find answers for:

What chemicals are linked to thyroid dysfunction? We have been doing a lot of research on everything that can be found in the house but nothing is coming up as definitive. The problem is that all the dogs would have the same exposure to most of these, so surely all would have issues? The main ones used are:

- aerogard (timeframe fits as it wasn't really used until about Sept/Oct, Canberra didn't have a mozzie problem)

- Aqium hand sanitizer (was used previously but not in the quantities it is now)

- dimethyl phthlate (has been stopped as of this week)

- teflon is used for cooking, but always has been and I would expect other dogs to have the same issues (and the 2 with hypothyroidism are never in the kitchen area of the house, in fact 1 hates being inside full stop). So that doesn't really fit.

What bacteria/viruses could affect the heart? I know there is a lab in the UK that can test for more viruses than we can in Aus, but no idea where to start.

Is there anything that we could be missing? His diet is the same as numerous other dogs in the pack who are showing no issues, he spends less time outside and doesn't venture as far as they do, and rarely leaves the property unlike the others. There are 3 dogs older than him and 1 only a little younger so not an age or period of exposure issue either.

What other tests could we look at running? No expense will be spared with this dog (who unfortunately is not insured), but we don't know where to go from here. He is an otherwise happy, healthy dog. He is full of energy, his coat looks great, and other than the increased panting (from the heart issue) and extreme weight loss appears to be perfectly fine.

Any suggestions or similar cases would be greatly appreciated :)

[Andrea]

Hi there, you haven't mentioned when was he (they) were last vaccinated?? vaccinosis??

[DeltaCharlie]

Hasn't been vaccinated in many years, all the dogs are titred instead. Not sure of exact dates for this dog, the younger ones with the hypothyroidism have only ever had puppy shots and were titred at the same time as the thyroid panels were done.

[Erny]

A couple of things first spring to mind in giving you some ideas/tips -:

A further test you could run that might give you some more insight is a hair-DNA test. I run mine through Ross Wilson at Coburg Health and Nutrition here in Victoria. Not all or many people believe in them but I have found it helped me. The good thing is that you can arrange this simply by sending a hair sample in by post. You don't have to say what your dog's symptoms are. The only thing I do though is to let them know what medications my dog might have been on at the time (if any). This makes the result report very interesting as the symptoms of what they suggest can indicate to you as to whether you can place your faith in it. I hope that makes sense. I was skeptical at the beginning so that is the way I approached it.

The second thing I thought of (this, in response to your "what other chemicals" question) is the possibility of lawn fertiliser. Mercury (for one thing, not necessarily the only) can be found in some fertilisers. Our dogs walk and roll in it and then lick themselves. A quick and easy way of ingesting mercury (and other contaminants)!! In fact, google around for information regarding heavy metal toxicity. If that is a possibility, the hair-DNA test should help to identify too.

Your dogs likes to lick walls and floors? Is it an old home and what type of paint has been used?

Blood tests can be done for heavy metal toxins and if these haven't been run, it is something I would ask for. But blood tests are only 'sensitive' to a certain extent and if they come back as negative I don't believe that doesn't mean there isn't a certain level of toxicity there. So I'd still be inclined to run the hair-DNA text as well.

For your dog's skin care (including feet) in the meanwhile that you're working through all this, have you tried wash/rinsing with Calendula Tea? This won't cure the other issues but it may help to sooth your dog's skin symptoms whilst your investigations continue.

I'm glad you've contacted Dr Jean Dodds - that's one base I would have suggested be covered, if you hadn't already.

Sorry - I'm flicking back to the OP to check on info as I type, which means my post is a bit all over the shop. Is there a possibility that the 3 dogs with thyroid issues are related in lineage? This question as an 'out-there off-chance'.

Good luck with your searching to find out what is going on with your dog. He's in good hands by the sounds and your friend and yourself are being super thorough.

Edited February 27, 2015 by Erny

[DeltaCharlie]

A couple of things first spring to mind in giving you some ideas/tips -:

A further test you could run that might give you some more insight is a hair-DNA test. I run mine through Ross Wilson at Coburg Health and Nutrition here in Victoria. Not all or many people believe in them but I have found it helped me. The good thing is that you can arrange this simply by sending a hair sample in by post. You don't have to say what your dog's symptoms are. The only thing I do though is to let them know what medications my dog might have been on at the time (if any). This makes the result report very interesting as the symptoms of what they suggest can indicate to you as to whether you can place your faith in it. I hope that makes sense. I was skeptical at the beginning so that is the way I approached it.

I had already considered this actually, as I was going to be asking for a collection kit for one of the other dogs so thought we could do both at the same time. This was the lab suggested to me, apparently they do animals too. I just wasn't sure what to be looking for with him.

Interclinical

The second thing I thought of (this, in response to your "what other chemicals" question) is the possibility of lawn fertiliser. Mercury (for one thing, not necessarily the only) can be found in some fertilisers. Our dogs walk and roll in it and then lick themselves. A quick and easy way of ingesting mercury (and other contaminants)!!

No lawn fertilisers used, have confirmed with the owner too. The grass grows out of control as it is without helping it along :) Generally any form of fertiliser is avoided because of the dogs, they love to munch on long grass etc so not worth it.

For your dog's skin care (including feet) in the meanwhile that you're working through all this, have you tried wash/rinsing with Calendula Tea? This won't cure the other issues but it may help to sooth your dog's skin symptoms whilst your investigations continue.

I've used it before for a dog with allergies and hot spots, but I wasn't sure if this would help as it is an actual injury that has caused it. The ligaments in his foot have collapsed so the toes rub together when he walks, hence no long walks etc. The only way to stop the rubbing completely would be to amputate a toe but that is a little drastic at this point in time. Until they flared up with the swim (the water softened the skin too much and it opened up again) it had been fine for quite some time. I suspect he is licking out of habit now, he is a little obsessive like that...

[Erny]

Ok, so I'd go ahead with the hair-DNA test AND I'd ask for thorough blood test to rule out (or in) heavy metal toxins.

(Don't want to be a scare mongerer, but fertiliser contaminants can remain in the soil for a long, long period of time - beyond current owner?? So whilst it is maybe unlikely to be an issue, bare it in mind.)

I'm no Vet so I can only give you what I've learnt through personal experience.

The Calendula Tea would only help the skin damage itself, not the cause of it.

Edited February 27, 2015 by Erny

[brightstar123]

I would speculate that diet could be the underlying cause in this case.

http://www.ncbi.nlm.nih.gov/pubmed/22931400

Have you been feeding any whole/large parts of raw carcasses that could contain thyroid tissue?

Sometimes in humans concurrent infection (like of the heart valve, for example) can cause a 'thyroid storm' or severe acute thyrotoxicosis.

For example, here's a case in a person where a thyroid storm was triggered by H1N1 infection:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2883193/

Obviously not a dog but I have heard of a similar case where the dog was clinically quite well and a severe skin infection triggered a thyroid storm (underlying cause was thyroid cancer). What are your dog's teeth like? Has he had a recent dental? Was the skin infection quite severe? Any other recent wounds? All these things can lead to infection/inflammation of the lining of the heart and valves, as I'm sure the cardiologist at ARH explained.

The endocarditis (inflamed heart valve) may be unrelated or perhaps it could have triggered the thyrotoxicosis, it's hard to know. Either way, I would change the diet (as you have), monitor clinical signs and retest T4 after several weeks.

[DeltaCharlie]

Initial results have come back indicating an infection of some sort (they are not sure what yet) so he is starting on some broad spectrum antibiotics. They have also indicated neutropenia (low WBC) but the lab is unsure as to whether he is not making enough or is using too much. Either way, another indicator that something underlying is going on. So far nothing has grown on the cultures but wouldn't expect that yet regardless, it was only started today.

His teeth are not great and never have been. He doesn't do well with bones so gets less than all the others, only 1 a week, occassionally 2. He is in need of a dental but too risky with his heart the way it is at the moment.

The skin infection was pretty mild, the toes had rubbed together and opened up the skin between but it was being cleaned daily and he wore his splint to keep off the toes until the wound closed up. He was licking at where the vet wrap had held the splint on, which led to a few small hot spots. They were cleaned too and once the DMP was used the whole thing closed up and its looking pretty good now. Its definitely possible that an infection could have got in as it was an open wound, although the symptoms started about 2 months beforehand. The initial issue with his foot happened about 12 months ago, could an infection have got in then and lay dormant until some sort of stress allowed to resurface? A new puppy was added to the pack in early Nov (he is sensitive to changes like that, especially puppies as he hates them) so it would have been a possible time of stress.

It is entirely possible that the meat he consumed contained thyroid tissue as it is not a human grade meat. One of the main reasons we have taken him off it. He did best on beef (he has always had a sensitive gut and doesn't tolerate many foods) so I would not be surprised if that contributed to the issue.

[brightstar123]

Thyroid storm can be triggered by both physical and mental stresses, such as infection, injury, surgery, poorly controlled diabetes, pregnancy or labor etc. It is certainly possible stress from the new pup could have contributed if that really bothered him - did this coincide time-wise?

Good to hear about the antibiotics, the neutropenia is a bit of a worry. Antithyroid meds (or several other meds like phenobarb) can cause severe neutropenia but I assume he hasn't been started on those. Obviously, the most likely cause is infection (bacterial sepsis would make sense as a cause of the endocarditis), hopefully the culture results will be helpful. I'm sure the specialists at ARH are on top of everything :)

[DeltaCharlie]

A bit of an update but nothing really to add.

Urine cultures haven't managed to grow anything so they are looking at doing blood cultures. To do that he needs more blood drawn so will need to be taken back off the antibiotics for a few days beforehand. The vet is waiting to confirm with the specialist centre before that is done though, so at the moment he is still on the antibiotics to hopefully kill off anything that may be in there.