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CRF, diabetes insipitus and psychogenic polydipsia

June 24th, 2009, 03:14 PM
Hello All,

In December of last year I told you of my cat who went in for a dental cleaning, tooth extraction and the biopsy of a lump. The cat was given an overdose of Metacam 0.4 mg/kg as opposed to 0.2 mg/kg but this was
discovered soon afterwards and she was put on an IV for 24 hours. Here is the original post:

Anyhow, here is a brief summary with a bit of additional information from January (this was good) and then finally the bad now.

Just prior to surgery a blood panel was done and her bun and creatinine
25.21 and 1.56 respectively (In SI terms 9 and 138 respectively). A week after the IV was withdrawn she was tested again and her bun was down to 22.41 and creatinine was up to 1.92 (normal range of the lab is from 0.57 - 2.00). In SI terms it was 170 on a scale going up to 177. I then heard something which has become a mantra with the vets there and that is normal is normal (which is not correct as high normal is indicative of something and there is indeed creatinine staging re renal disease). Urine Specific Gravity was at 1.035 which I was happy with, albeit not as concentrated as I would have liked.

Go forward a month to January and I had another panel done and this was good. Bun was 21 (SI unit 7.5 mmol/L) and creatinine was 1.40 (SI unit 124 umol/L). I assumed this event was behind me as these were great values.

A couple of weeks ago I started noticing her drinking more than normal. She eats almost exclusively canned - about 1 1/4 5.5 ounces a day with a little bit of added dry. But not much. Six months ago she was eating roughly 2-1 wet to dry. I measured her water intake and whilst varying I would put it at about 160 ccs a day. This still was quite a lot more than what she would drink before. I was getting really nervous now.

Last Friday I took her in for a complete geriatric panel (she is 11) and hopefully a urinalysis. Unfortunately, her bladder was empty and with her previous experience I did not want to leave her there for hours. I received the bloodwork Monday and with the glucose fructosamine test I specified in addition to standard glucose (through prior experience) and the T4 I ruled out diabetes mellitus and hyperthyroidism (what I was hoping for). However, and this was unfasted so bun could be elevated her creatinine was up again 1.92 (lab maximum is 2.0) (SI unit 170 with lab maximum of 177). Her Bun was 26.89 (SI unit 9.6 mmol/L max 13) with a maximum for the lab of 36.41. This is what it was essentially in the first few weeks after the overdose. But in December and January there was no polydipsia.

Clearly a urinalysis and USG needed to be done and I took a sample yesterday and ran it to the vet. They checked it there and the USG was 1.009 which shocked me. It was not the first pee of the day but somehow I don't see it getting much better. No infection was seen.

To me this was all related to the Metacam incident whereas the vet repeated the "normal is normal" with the high creatinine. She felt it might be due to diabetes insipidus (which is quite rare) or perhaps it was psychogenic (compulsive drinking) which I doubted very much as well. Just to add everything else was fine with no hypercalcemia, hypokalemia etc. She had by the way also lost 2 pounds since December but that could be diet (clutching at straws time) but she was still chubby at 12 pounds.

Anybody have any ideas on this? I will have another urinalysis done, either tomorrow or on Monday and try and make sure it is the first of the day but with the drinking I do not see it changing much.

All replies most appreciated.


June 24th, 2009, 05:28 PM
Here's some info on diagnosing causes of PU/PD that you might find useful:

Maybe a Desmopressin trial would help determine if Diabetes Insipidus is the culprit?

June 24th, 2009, 05:40 PM
Thanks very much. It is most appreciated.


June 24th, 2009, 09:42 PM
Any other symptoms aside from polydipsia/polyuria and weight loss?

Any value on the lab results that is out of normal range?

Has the vet mentioned normal/abnormal size/shape of the kidneys on physical exam?

Have you considered an ultrasound of the kidneys?

Aside from HyperT and Diabetes there are several other possibilites for polydipsia / low USG including:
Pyelonephritis ( aka bacterial infection of the kidneys - different from a UTI. With Pyelonephritis it is common for nothing to grow in a culture so an ultrasound is used for diagnosis.

Polycystic Kidney Disease ( different from CRF where cysts develop on the kidneys, diagnosis also via ultrasound.

Liver disease may also cause a low USG

What's the cats name?

June 24th, 2009, 11:55 PM
Hi Growler,

I will be seeing the vet probably on Monday for an exam (I saw just the vet tech as it was a rush) and may well add a Free T4 and a Desmopressin trial for D.I. although I know the latter is rare. The vet has an ultrasound there and that can be done even if it is just confirm the state of the kidneys.

I will probably do another urinalysis and hopefully get the first am sample but I do not expect wonderfully different results. I will also have a urine culture on a cysto sample to rule out occult infections. I will also have her blood pressure checked over a 30 minute period.

All levels in the Geriatric Panel were otherwise normal. No indication of liver disease at all, Cushings etc. Even though the Bun and Creatinine are within normal range (high normal) the USG is the first to go. I am just wondering why with the same levels as in December last year there are clinical symptoms - polydipsia and polyuria - which were not present then. But, even though the vets I have here may disagree I think there is renal insufficiency.

Her name is Samantha but I first called her Sam when I did not know her sex. She was a kitty who from a very young age visited my garden apartment and who I fed for years on a daily basis until she trusted me enough and came inside to live.

June 25th, 2009, 12:12 AM
Yeah the problem there is the blood kidney numbers are normal but if you base soley on the USG you're looking at possible renal insufficiency.

A urine culture is a good idea just to be sure there is nothing hiding.

:2cents: I would also have the ultrasound done, if there is Pyelonephritis (bacterial infection of the kidneys) most likely nothing will show on the culture, but you can have a clear picture of the physical state of the kidneys.

Samantha is lucky to have found you :D Any chance we could get a pic or 2? :D

June 25th, 2009, 09:19 AM
Hi Growler and Sugarcatmom,

A bit of an update.

This is getting curious. Or perhaps I am really at clutching at straws time. In the last 24 hours there has been a change. Is it significant or just something transiently positive? I do not know.

I believe I mentioned that I was feeding the two cats Nature's Variety canned and I have been using this food in various flavours for about the last 4 months. I always look at the nutrient content and for nature's variety Prairie/Homestyle (they do not like the Instinct canned) the figures are pretty good. I have always chosen lower phosphorus canned food for my kitties and these are not bad at all at around 1% on a DM basis. Sodium was not that high either although higher than some foods at about 0.6% on a DM basis.

Well, I had run out of the Nature's Variety and with all the rushing on Tuesday I went to the closest pet store which normally has little super premium and I bought 4 cans of the new Hill's Culinary Creations canned. Carbs too high for a canned food but sodium I noticed (on checking was about 40% less than Nature's Variety.

Anyhow, Yesterday morning I continued my measuring of water consumption (having a control bowl as well for evaporation) and even though I cannot be exactly precise I do know who drinks from which bowls (3 of them). This morning checking water consumption I work out that Samantha must have drunk less than 100ccs of water in the 24 hour period. The litter box clumps are also markedly less than on some days.

This was all intriguing me and I decided that I would see if I could get a free catch sample this morning. I know it was not the first of the am (since midnight last night) but I managed to get one. A friend of mine has taken this to the vet now. All I am looking for at the moment is USG but what was somewhat heartening is that the colour was more yellow. I feel there is a good possibility that this is better than what I got on Tuesday - 1.009 - but I doubt it is at say 1.030. Just taking small baby steps now and perhaps this whole thing is just a red herring.

Edit: When I say "red herring" I really intend to say that all this reduced water consumption etc is a false hope on my part that matters are somehow materially improving.

June 25th, 2009, 11:53 AM
Well, that did not work out too well. I was just faxed the USG and it is essentially the same 1.011. Really disappointed as the colour looked a deeper yellow.

One thing I did not mention early is that I had emailed the vet yesterday as to whether we should do an E.R.D. Screen test, aka microalbuminuria. Seemingly the vet agrees and it will be done.

Here is what it is about:

June 25th, 2009, 01:17 PM
One thing I did not mention early is that I had emailed the vet yesterday as to whether we should do an E.R.D. Screen test, aka microalbuminuria. Seemingly the vet agrees and it will be done.

Good idea:thumbs up. Hope that gives you some more answers.

June 25th, 2009, 11:35 PM
USG concentration is a little better that's positive news anyways.

Good plan to have the microalbuminuria test done :goodvibes: for good results

June 29th, 2009, 04:20 PM
Matters are becoming a bit more confusing now. I have the results of the E.R.D Screentest/Microalbuminuria and it is negative which is a surprise. For a negative test the kidneys have to be undamaged (and this is sensitive all the way down to 25% damage).

June 29th, 2009, 11:59 PM
Having no indication of kidney disease is excellent news :thumbs up

I do feel the need to point this note on the ERD site though, just because Samantha's USG is really really low:
NOTE: Circumstances exist when the E.R.D.-HealthScreen® tests may be negative, yet the patient has underlying illness; such as the following:

A patient with end-stage renal disease may test negative for microalbuminuria.
The particular disease condition generally does not damage the nephron.
The disease condition has not led to detectable nephron damage at the time of testing with the E.R.D.-HealthScreen® tests.

What has your vet said about doing the Desmopressin trial to test for Diabetes Insipidus that SCM suggested?

Has Samantha been treated with any steroids, either corticosteroids or anabolic steroids such as Prednisone, Prednisolone, Hydrocortisone, Depo-Medrol, Dexamethasone (aka Azium or Voren), Stanozolol (Winstrol-V) and Nandrolone (DecaDurabolin) etc?

Is it really hot where you are? Is the air in your home very dry?

Just wondering of the environment is playing a role in the increase in drinking instead of a health issue since so far everything is pointing to Samantha being perfectly healthy. :shrug:

June 30th, 2009, 09:40 AM
Hi Growler,

I have really been scratching my head as to what the cause is. She has not received any prednisolone or any other medication for over 2 years. My apartment is air conditioned and with my water consumption tests (using a control bowl) the air is not overly dry by the evaporation rate. I do know that the ERD Screen coming back negative will rule out a few other possible disease states but not all.

I will probably do a consultation with the Cornell Feline Health Center in Ithaca NY - very reasonable - US$55 per call and there I would speak to a specialist after forwarding on all the blood work and tests.

I will probably only do further testing next week when I get a handle on what exactly I am going to test for. Free T4 and a Desmopressin trial are quite probable. I cannot, however, get it out of my mind, that my one vet in Vancouver - now retired - never encountered a single case of diabetes insipidus and the vet in Montreal also has not seen one. Clinically Sam seems fine so I feel I do not, at the present moment, have a lot of pressure on me to throw a barrage of tests at her.

I will not, however, just leave it as it is.

July 8th, 2009, 06:20 PM
Hi All,

Over the weekend I spent an enormous amount of time researching her situation in Pubmed etc and I have come to the conclusion that Samantha is in the position of renal insufficiency. I spent a lot of time digging around with the ERD Screentest/Microalbuminuria by Heska.

The upshot is I believe that they are not being completely truthful on their website. I quote from the client section:


A negative test is reassuring because it indicates your pet has no current damage to the kidneys."

That seems great but in checking essentially many diseases of the kidney are noted for proteinuria/microalbuminuria but not all. Quite a few are not. I phoned Heska and I asked if this was 100% correct because I had peer-reviewed studies that indicated otherwise. The individual I spoke to was hedging a bit and I said "I am just quoting what is on your website." I pointed out the few exceptions they do note on their site but what I pointed out was the fact that several kidney diseases are not noted for the release of any microalbumin or other proteins. I advised them to change their website but they have not.

So tomorrow is a physical exam with another panel or perhaps just bun, creatinine, phosphorus and potassium. All those so far are within normal but I want to see if things are deteriorating or not. I am going to do it fasted as I do note that creatinine can increase by up to 50% if a cooked meat meal has been ingested within the last 4 hours. Since here great test in January was 124 for creatinine and it was fasted I want to properly stage this.

I will see if a cysto sample can be done for a urine culture to be done (microscopic examination of a dilute sample will not show bacteria) and I will have her blood pressure checked.

I will also stick her on Omega 3s which while shown to be reno protective in dogs nothing much has been done with cats. Depending on how her kidneys feel and her thyroid I might have an X-ray or ultrasound done.

July 10th, 2009, 08:22 PM
As I mentioned I would do, I did an update - a geriatric panel and also was hoping to get a cysto sample for a culture. No luck with the cysto sample but her geriatric panel came back and not good. Things have deteriorated quickly. Bun has jumped to 13.2 from 9.6 SI units (US is now 36.97 from 26.89) and creatinine has jumped from 170 to 224 (US from 1.92 to 2.53). I even did a 12 hour fasted sample as I have seen in peer-review studies that creatinine can increase by up to 50% if a cooked meat meal is ingested within 4 hours.

I was hoping to do a Free T4 but they messed up there but, whatever, her T4 level is 45 on a scale of 11-46. She is probably hyperthyroidic I fancy if I did a Free T4 but in a way that is being probably a bit reno protective (but bringing with it other problems) because if she were on Tapazol her Creatine and Bun would really go up.

USG is 1.010, like the 2 other readings. Lymphocytes are just below normal so perhaps there is some infection there but I don't know without a urine culture. I also wanted to do blood pressure which I know is often a huge factor and he brushed it off (the vet owner)

And all of this is I am sure due to the Metacam overdose.

When I was having her blood etc done 2 weeks I looked through her file. It was all loose sheets, all over the place, nothing punched in order to properly collate the pages. Included with her file was the bloodwork of another dog or cat. How about that? I will give her some good Omega 3s next week - DVM 3Vs as I know it is reno-protective in dogs but there is little on cats. Sub-Qs not at the moment as she does not appear dehydrated. Phosphorus is fine being on the low end of normal.

The problem is that living in Montreal now as opposed to Vancouver and after going into a couple of other vet practices here I don't have the first clue about where else to go. I had in Alf Burt and Anne Irwin and various specialists at the Critical Care Group in Vancouver (now called the Canada West Veterinary Specialists and Critical Care Hospital) wonderful care.

And this vet practice is one of the pre-eminent English ones in Montreal - I am not going to mention names. As I said to one of the employees, a culture of sloppiness pervades the practice in so many areas I have noticed.

July 11th, 2009, 12:40 AM
I would say you definately are looking at renal insufficieny now, being fasted both the bun & cre should have dropped from the level they are currently under normal fed conditions, so you are likely actually looking at numbers that are a little higher than this last test. (When my CRF cat was recently hospitalized due to food allergy, what little she had eaten the day before & that morning had been vomited back up - esentially like she hadn't eaten- & when they tested her before any meds/fluids were given her numbers were dropping into normal range & when completely normal after several hours on IV fluids) So basically Samantha's "actual" properly-fed numbers will be slightly higher than a fasted test.

With a T4 of 45 I would say she is also either on the verge of HyperT (most likely though) or you caught a high in the number since the values do fluctuate throughout the day. HyperT can also mask the symptoms of CRF and once treatment is started for HyperT the CRF becomes more apparent

As for the blood pressure - many vets won't do it because they feel the test is not acurate enough for a stressed cat with possible health issues including possible low blood flow due to kidney issues, and since it's only one test they have no history to base it on :shrug: I've had blood pressure taken on a very stressed badly constipated CRF cat in a "white coat syndrome" conventional vets office (as opposed to her calm homeopath's office) and her blood pressure came back normal @ 120. The BP was repeated a couple of months later during this last hopitalization under similar stressed conditions this time an allergic reaction & it was also normal 120.

Metacam is very likely to be the cause as CRF is a potential risk to develop due to prolonged exposure, diabetes is as well.

The staff @ Canada West is great aren't they :D I had to take my :rip: dog there several years ago.

July 12th, 2009, 01:26 PM
Hi Growler,

Thanks very much for replying. Clearly the very high normal T4 is a complicating feature here. By the way, a T4 was also done some 2 weeks ago and it was lower - 37 on the scale of 11-46. What is so upsetting is that I had pointed out initially that I think there may be a hyperthryoidic issue at work as well. When I brought her in on Thursday I repeated my concerns about hyperthyroidism. I then asked for a Free T4 and I do see when looking at Idexx's website that there is no "standard" Free T4 as in canines.

The only test for this is the following:

"Free T4 Equilibrium Dialysis Radioimmunoassay" which takes a week for results as it is sent out. The other 2 Free T4s for dogs are all same day. The odd thing with this practice is that both the vet owner and the other vet assumed that there was a simple request to Idexx for a switch from a Total T4 to a Free T4. It would appear that neither has of late ordered a Free t4. Despite

I will be consulting with Cornell Feline Health Center this week - from previous experience I get to consult with a board certified internist and they spend a fair bit of time with you. I will also be contacting the St Hyacinthe veterinary teaching hospital and from there I hope to get pointed to a referring hospital with an internist.

Clinically, Samantha seems no different thank heavens but if the current trajectory continues she will shortly be a Stage 2 as opposed to a Stage 2.

July 14th, 2009, 12:43 AM
I think a high end normal T4 in a senior cat is all you really need to diagnose HyperT. As mentioned here on Idexx Snap T4 Test ( site page:

Feline hyperthyroidism—Experts agree that a diagnosis can be made from a single high T4 result. Because euthyroid sick patients have suppressed T4 and T3 concentrations, concomitant hyperthyroidism should be considered in any middle- to old-aged cat with a nonthyroidal illness and a high-normal T4 level, especially if clinical signs are present.

Any questions about HyperT let me know I've dealt with that too.

Re CRF Stages: One thing about the stages, as well as all blood/urine values - they do fluctuate all the time. So in 1 test it may look like Stage 3 but the next test 3 months later it's Stage 2. The key is not to focus so much on the numbers but how Samantha is feeling. Is she her happy purry normal self or does she seem depressed, not wanting to eat, hiding etc.

If you haven't already have a look through this site: loads of not only medical info but real person experiences living w/CRF cats

Good luck with the consults :goodvibes: