Experience with Diabetes insipidus or psycogenic polydipsia?

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Anthony Todd — Wed, 07 May 2014 23:53:44 GMT

http://en.wikipedia.org/wiki/Psychogenic_polydipsia

May be of interest [condition in people]

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Andrew Kent — Wed, 07 May 2014 19:51:06 GMT

A bile acid stimulation test would sound like a good idea to look for liver dysfunction as I don't think thats been done? Otherwise I would look again for a pyogenic focus with imaging and repeat cysto if all other possibilities have been ruled out.

Andy

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Stigen — Wed, 07 May 2014 19:34:57 GMT

[quote user="Neil Wheadon"]

In over 20 years, I've only been convinced of Diabetes Insipidus in one case.

Can you expand on the history here. There seems to be only one SG test at 1.012 where Insipideus is classically <1.005, have you done more than one urine SG? I'd also make sure that the dog is drinking as much as the owner says, so would ask them to measure the amount drunk in a day. (I admit you may have already done this but it's not in this post) Even doing a very simple at home water deprivation test would help by asking the owner to collect a sample when the dog urinates and then without water, then looking for an increasing SG.

I have though seen a lot of cases where the SG was really low and I'm talking 1.003. However all have 'self cured' over a period of a few months and Anthony's suggestions of reducing drinking for pleasure may help.

I know this is all pretty low tech but I think DI is very rare and time will heal the vast majority

Neil

[/quote]

The sg has been 10012 , 1008 and 1005 , I have asked her to measure exact water intake over the next 24 hours.. I guess it is unlikely to be DI , but I`m running out of differentials. I think I will ask the lady to do what Anthony suggested, to boil it and serve it lukewarm.I don`t entirely understand why that would make it less palatable,but interesting to try.

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Stigen — Wed, 07 May 2014 19:06:28 GMT

[quote user="Andrew Kent"]

I would echo Neil's thoughts on this that urine specific gravity is key to this - how many times has this been measured and what kind of figures have you seen? I tend to hospitalise these dogs and measure their 24 hours water intake and a USG on every sample to see if they can ever concentrate - if they can you rule out DI.

In this case with a USG of 1.012 I would consider central DI very unlikely.

Andy

[/quote]

It `s been measured 3 times at 1005,1008 and 1012. I have asked her to measure the water intake over 24 hours unrestricted. She says that the dog is so desperate for water that it runs towards every puddle of water when they are out walking, and the dog drinks a whole half litre water bottle that she has brought...which should be enough water for 24 hours for a dog that size...
If I rule out DI I`m not left with a whole lot of differentials....but I might test the ACTH just to make sure it is`nt some weird form of Addisons.

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Andrew Kent — Wed, 07 May 2014 18:42:21 GMT

In this case with a USG of 1.012 I would consider central DI very unlikely.

Andy

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Neil Wheadon — Wed, 07 May 2014 18:08:58 GMT

In over 20 years, I've only been convinced of Diabetes Insipidus in one case.

I know this is all pretty low tech but I think DI is very rare and time will heal the vast majority

Neil

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Martin Atkinson — Wed, 07 May 2014 17:59:12 GMT

[quote user="Stigen"]The basal cortisol level was quite low, but the stimulation was acceptable, and the clinical sign and age of onset is atypical for Addison. I[/quote] Don't you believe it, I am currently treating a dog with Addisons that started at 6 months, even the RVC wouldn't believe it when it ended up there as an emergency OOH over a weekend but I was proved right. Things that suggest it besides your low cortisol levels are ureamia, relatively high eosinophil count and low sodium. Against your post ACTH cortisol of >55 and the Na:K ratio is 33 which should rule it out but my case showed symptoms if its Na:K ratio fell below 30. I would closely monitor your Na:K ratio. Desmopressin response is no substitute for a water deprivation test but it may buy you some time. IME you don't need to deprive for 24 hours in most cases you just need consecutive urine samples that show increased USG. That said the USG of 1.012 probably rules out DI which is so rare as to be virtually excluded anyway. Meanwhile keep treating for UTI.

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Anthony Todd — Wed, 07 May 2014 16:58:12 GMT

[quote user="Stigen"]Any thoughts or experiences on this ?[/quote]

First thing I used to do was give only boiled water, luke warm too which seems to taste not so nice and compare consumption. Sometimes the change is dramatic!

Make sure the dog is not getting it from other sources.

If no change then there's a problem, if it reduces intake significantly then it's psychogenic and it's boiled or restricted water from then on.

Re: Experience with Diabetes insipidus or psycogenic polydipsia?

Bob Russell — Wed, 07 May 2014 16:22:07 GMT

Diabetes Insipidus tend to pee almost pure water and drink buckets in my experience. Never convincingly diagnosed psychogenic polyD. DI has generally turned out to be secondary to Cushings.

We had an elderly Newfoundland that was drinking one end and peeing the other at the same time. Improved with control of the Cushings. Does not seem a good match to your case.