Concurrent DM and Cushings?

RE: Concurrent DM and Cushings?

Martin Atkinson — Tue, 01 Nov 2016 17:22:38 GMT

The problem with your suggested approach Julian is that no-one has yet diagnosed HAC in the OP's dog. The high ALP could be due to the persistent hyperglycaemia and you may get a false stress picture giving an artificially high and equivocal ACTH stim test. Plus there is disagreement in the ranks over the value of a LDDS test. So you need to treat the DM first. Then if symptoms suspicious of HAC persist or the DM is refractory to treatment go looking again.

RE: Concurrent DM and Cushings?

Julian Earl — Tue, 01 Nov 2016 16:37:43 GMT

A key question is which to focus the treatment on? My belief had been the Cushings first as long as keto-sacidosis is not a threat. But because steroids induce insulin resistance it is necessary to deal with that first. Any other views on this please? However; my endocrine emergenciesCPD- notes from Dick White referrals say always treat the diabetes first including underlying diseases such as concurrent diseasespancreatitis/dental disease etc., etc.

RE: Concurrent DM and Cushings?

Martin Atkinson — Tue, 01 Nov 2016 14:01:07 GMT

[quote user="Aine Seavers"]yet to see it in a Siamese ever.[/quote]I have seen at least one Siamese and 2 Burmese that I recall.

[quote user="Aine Seavers"]surprised the canned fish theory has been disproved [/quote]Haven't said it's disproved just it's not proven.

[quote user="Aine Seavers"]The grooming also an issue for cats whose owners smoke and risk of other cancers-there were a few papers showing analysing hair and nicotine levels that didnt bode well for future health in dogs/cat [/quote]This was mentioned as well. I've seen several cases of feline asthma related to smoking, cancer is a bit more difficult to relate.

RE: Concurrent DM and Cushings?

Aine Seavers — Mon, 31 Oct 2016 21:52:32 GMT

yet to see it in a Siamese ever. Do see a 100% correlation b/n cats on tinned fish cat food and the disease so am surprised the canned fish theory has been disproved as its been the one constant in every cat that has had hypert4 here. The grooming also an issue for cats whose owners smoke and risk of other cancers-there were a few papers showing analysing hair and nicotine levels that didnt bode well for future health in dogs/cat but esp given the grooming habits of the cats.

RE: Concurrent DM and Cushings?

Martin Atkinson — Mon, 31 Oct 2016 13:57:17 GMT

[quote user="Anthony Dennison"]There was a meta-analysis I read for one of my case reports that said the use of flea and worming treatments if looking at the date in a certain way could be considered goitrogenic, but this was put down to if the cat was being well looked after they were more likely to seek veterinary attention.[/quote]The meta-analysis of the statistics in David's team's survey was weighted so that it compensated for factors that could skew the results like age, posh owners, veterinary attention, diet etc and that is how it came to the conclusion that it was 12 times less likely for purebred cats to have hyperthyroidism. It is then conjecture that the pigment and halogenic contaminants in the environment combine to form goitrogenic compounds in-vivo as they have in-vitro but it is an interesting theory.

RE: Concurrent DM and Cushings?

Emily Rainbow — Mon, 31 Oct 2016 13:40:16 GMT

Interesting comment in this weeks vet times comparing disease in hong kong I think. a comment that hyperthyroidism isn't very common compared to here and that the author suggested it was down to these goitrogenic compounds.

RE: Concurrent DM and Cushings?

Anthony Dennison — Mon, 31 Oct 2016 12:09:40 GMT

[quote user="Bob Russell"]

I assume that the suggestion that high tuna diets may contribute to hyperthyroid levels has now been disproved?

It seemed to be a popular suggestion a few years ago.

[/quote]

Not the tuna per se, but there are certain goitrogenic chemicals from canning. Some from the tins themselves, some as by-products from the canning process/sealing, if I remember rightly.

There was a meta-analysis I read for one of my case reports that said the use of flea and worming treatments if looking at the date in a certain way could be considered goitrogenic, but this was put down to if the cat was being well looked after they were more likely to seek veterinary attention.

RE: Concurrent DM and Cushings?

Martin Atkinson — Fri, 28 Oct 2016 14:53:33 GMT

[quote user="Bob Russell"]I assume that the suggestion that high tuna diets may contribute to hyperthyroid levels has now been disproved?[/quote]Unless that was one of he moments I had a loss of attention span (difficult because David Church is such an interesting and involving speaker) nothing was said about specific foods, more their sourcing as to whether it is contaminated by goitrogenic chemicals but looking as the container especially plastics and all the stuff around the house, especially fire retardants as Scarlett suggested. It may be that tuna has come from fish which have been exposed to a potential goitrogen and it is carried down the food chain.

RE: Concurrent DM and Cushings?

Luca Poddighe — Fri, 28 Oct 2016 13:17:16 GMT

For what I've understood more than the food itself the problem seemed to be focused in the cans, but as well a lot of other stuff present in our household including dust.

RE: Concurrent DM and Cushings?

Bob Russell — Fri, 28 Oct 2016 13:08:01 GMT

I assume that the suggestion that high tuna diets may contribute to hyperthyroid levels has now been disproved?

It seemed to be a popular suggestion a few years ago.

RE: Concurrent DM and Cushings?

Martin Atkinson — Fri, 28 Oct 2016 10:51:22 GMT

[quote user="Scarlett Creasey"]When speaking about hyperthyroidism "goitregens" gets brought up as the term for substances thought to damage the thyroid and progress to hyperthyroidism. Some of the suggested goitregens are things like fire retardant coatings and additives to commercial pet foods. Not really any work done of these however....[/quote]Thanks for your input Scarlett, students are always nearer the cutting edge that us dinovets! Goitrogens was a word I was searching for. We did have a discussion on the presence of halogenated compounds being ubiquitous in our modern environment and it raises concerns as to our welfare let alone the cat's. It also clear that one reason cats are more vulnerable to environmental contamination than dogs, or indeed us, is because of their grooming habits - we may be OK unless we start licking ourselves instead of bathing!

RE: Concurrent DM and Cushings?

Scarlett Creasey — Fri, 28 Oct 2016 10:43:45 GMT

David Church is a wonderful lecturer, we have just finished the Endocrine strand with him at RVC.

The study he shared with us was this one (open access)

Feline Acromegaly: An Underdiagnosed Endocrinopathy? http://onlinelibrary.wiley.com/doi/10.1111/j.1939-1676.2007.tb03041.x/abstract

And they are working to publish more research that supports 25-30% of diabetic cats having hypersomatotropism. Pituitary masses can be removed (although obviously referral and CT and expensive+++) but if confirmed it might be a viable option for some clients if the cat is young and otherwise healthy?

When speaking about hyperthyroidism "goitregens" gets brought up as the term for substances thought to damage the thyroid and progress to hyperthyroidism. Some of the suggested goitregens are things like fire retardant coatings and additives to commercial pet foods. Not really any work done of these however....

RE: Concurrent DM and Cushings?

Martin Atkinson — Fri, 28 Oct 2016 10:18:21 GMT

Luca may be enlightening me or his explanation was lost in translation!

The poorly controlled diabetic cat was not showing phenotypical signs of acromegaly and indeed was losing weight which was the curve ball that threw us off the scent and sent us on the mystery tour. Apparently 25% of diabetic cats probably suffer from pituitary somatotrophism and yet most do not show the phenotypical symptoms. Indeed it may even be the the increased growth hormone production that induces the diabetes in the first place and this is so common that David suggested we should take a blood sample at the outset of treating all diabetic cats and store the frozen plasma for future use because when they become very hyperglycaemic the IGF-1 test may become less reliable.

Furthermore a lot of cats have pituitary somatotrophism without becoming diabetic and it was speculated that some cats which are chronically overweight may have this condition and it may be worth checking before purely blaming the owner for over-feeding them.

Luca is almost right in that David's research has shown that purebred cats are 12x less likely to become diabetic than moggies and speculated that it was related to breeding to genetically select cat coat colour for colour dilution (most pedigree cats don't have dark coats). It is speculated that it is the combination of the melanin pigment and halogen compounds in the environment combine to form a thyroid hormone analogue which can lead a reactive change in the cat's thyroid glands. My understanding of this is a bit sketchy at this point as my brain was in overload mode so I may be talking rubbish and will await the PDF of David's notes arriving before taking any further questions on this!

RE: Concurrent DM and Cushings?

Luca Poddighe — Fri, 28 Oct 2016 08:51:42 GMT

The talk was about medical mysteries one of the two cases presented was an apparent Diabetic cat been under a reasonable control for a couple of years and eventually slipped out of control. The final diagnose was a pituitary masses autonomously increting Somatotropin, since he was presenting the phenotypical changes we don't speak of acromegaly. At this point David expressed a theory that associates Halogenate compounds to both acromegaly and hyperthyroidism; He mentioned as well that in his opinion very little pure breed cats get treated for hyperthyroidism in proportion with moggies and he said he depends from the genes that regulate the black colour (undiluted) in the coat and that at the same time would regulate the sensitivity to Halogen compounds.

Now I will do the same question that David has asked us: do you see many pure breed hyperT cats? Let's get here some statistics...

P.S. I hope this will enlighten, but I fear it may cast some shadows...

RE: Concurrent DM and Cushings?

Noweia — Thu, 27 Oct 2016 22:28:25 GMT

[quote user="Martin Atkinson"]Should we enlighten the rest of the forum on what we learned of let them wonder and wish they were there?![/quote]

Enlighten please! Coat colour?

RE: Concurrent DM and Cushings?

Andrew Kent — Thu, 27 Oct 2016 20:21:39 GMT

[quote user="Martin Atkinson"]

[quote user="Andrew Kent"]Yep ACTH stim never as useful in cats as they have a very variable response to stimulation so the sensitivity is only ever reported to be 30-50% with this test.[/quote]I would still use LDDST as my test of choice for HAC even in dogs.

[/quote]

Agreed - as I said above LDDST is preferred in the majority of cases of HAC but it does have a lower specificity than the ACTH stim so higher chance of false positives. So when we have a known concurrent disease there is good logic to going for ACTH stim (in dogs this is).

The real plus of the LDDST is that in both forms of HAC the sensitivity is very high so a negative result makes the disease unlikely, ACTH stim has very poor sensitivity in adrenal dependent disease so misses a lot of cases.

Andy

RE: Concurrent DM and Cushings?

Martin Atkinson — Thu, 27 Oct 2016 15:09:15 GMT

[quote user="Emily Rainbow"]

Don't know how to quote you Martin... I was there too last night and wondered who it would turn out to be that mentioned this site! Really good evening I thought! Lots to ponder!

[/quote]Yup, I took the LDDS test out of its context. You might have heard me say to David that there was a thread on Vetsurgeon.org regarding that but I seemed to recall at the time it was for a cat not a dog.

It was certainly one of the better nights. David is a wonderful speaker and the stuff at the end about the predisposing factors for feline hyperthyroidism, both environmental and genetic/coat colour dependent was fascinating. I will certainly also be looking for acromegaly a lot more now.

Incidentally Luca was there as well. Should we enlighten the rest of the forum on what we learned of let them wonder and wish they were there?!

RE: Concurrent DM and Cushings?

Emily Rainbow — Thu, 27 Oct 2016 14:43:43 GMT

Don't know how to quote you Martin... I was there too last night and wondered who it would turn out to be that mentioned this site! Really good evening I thought! Lots to ponder!

RE: Concurrent DM and Cushings?

Ashlea — Thu, 27 Oct 2016 09:58:06 GMT

Thank you all, we'll concentrate on the diabetes for now and see what happens.

RE: Concurrent DM and Cushings?

Martin Atkinson — Thu, 27 Oct 2016 09:32:41 GMT

RE: Concurrent DM and Cushings?

Andrew Kent — Thu, 27 Oct 2016 09:00:07 GMT

[quote user="Martin Atkinson"][quote user="Andrew Kent"]If you do need to test in the future unfortunately ACTH is probably preferable as it has a higher specificity than the LDDST so slightly lower chance of false positives. LDDST is preferred for less complex cases due to the higher sensitivity.[/quote]I don't know how this applies to dogs but I went to a BSAVA meeting with David Church as the speaker last night and one of the cases we discussed was a a cat with refractory DM. His opinion on the tests for HAC was the opposite on the relative value of the tests and that LDDST was preferable especially in this scenario. His only caveat was to advise reducing the dose of insulin by 50% on the day you elect to do the test to reduce the risk of a misleading result.[/quote]

Yep ACTH stim never as useful in cats as they have a very variable response to stimulation so the sensitivity is only ever reported to be 30-50% with this test. Nobody really knows the specificities of the different tests as there are relatively few cases tested.

RE: Concurrent DM and Cushings?

Martin Atkinson — Thu, 27 Oct 2016 08:49:46 GMT

[quote user="Andrew Kent"]If you do need to test in the future unfortunately ACTH is probably preferable as it has a higher specificity than the LDDST so slightly lower chance of false positives. LDDST is preferred for less complex cases due to the higher sensitivity.[/quote]I don't know how this applies to dogs but I went to a BSAVA meeting with David Church as the speaker last night and one of the cases we discussed was a a cat with refractory DM. His opinion on the tests for HAC was the opposite on the relative value of the tests and that LDDST was preferable especially in this scenario. His only caveat was to advise reducing the dose of insulin by 50% on the day you elect to do the test to reduce the risk of a misleading result.

However it is not surprising that the liver enzymes are raised in a previously untreated diabetic so as suggested it may be best to attempt control of the DM first.

RE: Concurrent DM and Cushings?

Andrew Kent — Wed, 26 Oct 2016 15:48:16 GMT

Hi Ashlea,

Almost impossible to make an assessment of urine concentration in the presence of glucosuria - this creates an osmotic diuresis which will often cause very low USG's but at the same time the presence of glucose can artificially elevate USG so all together pretty meaningless.

The high ALP could be consistent with hyperadrenocorticism but could equally be due to vacuolar hepatic change due to the diabetes.

I tend to set about treating the diabetes first and only really look for concurrent disease if that doesn't go according to plan.

If you do need to test in the future unfortunately ACTH is probably preferable as it has a higher specificity than the LDDST so slightly lower chance of false positives. LDDST is preferred for less complex cases due to the higher sensitivity.

Andy

RE: Concurrent DM and Cushings?

Rob Loxley — Wed, 26 Oct 2016 13:50:24 GMT

I would expect a LDDST (and probably an ACTH stim) to be positive in an uncontrolled diabetic dog, cushing's or not. I'd get on and start treating the diabetes and park thoughts of cushing's unless the diabetes isn't coming under control and we're looking for a cause of resistance