Diabetes insipidous?? or renal failure (7 months old)

Re: Diabetes insipidous?? or renal failure (7 months old)

Robin Grimmer — Wed, 30 Oct 2013 23:10:58 GMT

Reduction in creatinine may be caused by loss of muscle mass. Do a manual pcv, quick and cheap.

Re: Diabetes insipidous?? or renal failure (7 months old)

Holly Lee — Tue, 29 Oct 2013 22:29:50 GMT

Thanks again for further replies. Baseline cortisol was 77nmol/l - must admit would have been happier with it in the 100s in a dog with another illness but with very limited synacthen in the building until who knows when- I was reluctant to do the stimulation with the information I had. I had wondered about a deficiency of aldosterone only. However now that electrolytes are completely normal again on todays results (both Na and K exact middle of range), I'm less convinced of the liklihood of addisons. If was cortisol deficient only presumably would not get the marked PUPD?

Interestingly though the creatinine has reduced from 312 to 229 since first measurements were taken a few weeks ago, with no treatment.

No haematology at this stage unfortunately - was cutting a few corners to try and keep owner on board.. Perhaps that would be a good next step.

Thank you especially for confirmation on the SG with DI as this was my main worry that I was over-interpreting that in ruling out DI.

Re: Diabetes insipidous?? or renal failure (7 months old)

Robin Grimmer — Tue, 29 Oct 2013 20:27:59 GMT

If hypoadrenocorticism is definitely ruled out, then chronic renal failure probably due to congenital renal disease is the diagnosis. DI would give a much lower SG, which would show active dilution by the kidneys. Your SG is isosthenuric which is typical for renal failure. An ultrasound might be useful. Is there a non-regenerative anaemia?

Re: Diabetes insipidous?? or renal failure (7 months old)

Glenn Hodgson — Tue, 29 Oct 2013 20:12:47 GMT

Just read briefly. An unexpected high urea in a young dog. I would also be carefull re addisons prior to pasding an unfavourable prognosis.

Re: Diabetes insipidous?? or renal failure (7 months old)

John Flynn — Tue, 29 Oct 2013 19:48:42 GMT

[quote user="Holly Lee"]I was of the understanding that a baseline cortisol of >55nmol/l DID rule out addisons disease - anyone else any opinion on that?[/quote]

It certainly makes it very unlikely, though doesn't strictly rule it out. I've seen a case which had basal cortisol of 90 or so and was assumed not to have addisons, however did have persistent hyperkalaemia, and ACTH stim had minimal stimulation to about 150 or so - also not ruling out addison's... had undetecable levels of adlosterone pre- and post- ACTH and has been very happy on florinef ever since. I don't expect to see another patient like that though in my lifetime.

If patient appeared fully hydrated, then would not typically expect azoteamia with diabetes insipidus.

Re: Diabetes insipidous?? or renal failure (7 months old)

Martin Atkinson — Tue, 29 Oct 2013 17:45:24 GMT

[quote user="Holly Lee"]I was of the understanding that a baseline cortisol of >55nmol/l DID rule out addisons disease - anyone else any opinion on that?[/quote] I've seen a few Addisons which present with very subtle laboratory findings. You haven't given a value for baseline cortisol if it was borderline ~ 55 I would still not rule it out. A Na:K ratio of >27 should rule it out but my young Addisonian dog has to have an Na:K ratio of >30 for me to be happy it would not have a crisis. Also some are lacking glucocorticoids only and will give a normal electrolyte ratio but glucose should be low or low normal. Also you should have reverse stress leucogram. You are probably right but I think Addison's is under-diagnosed especially in young dogs and it is so easy to treat compared with the other options that I would want to be sure.

Re: Diabetes insipidous?? or renal failure (7 months old)

Rob Loxley — Tue, 29 Oct 2013 17:36:56 GMT

[quote user="Holly Lee"]I was of the understanding that a baseline cortisol of >55nmol/l DID rule out addisons disease - anyone else any opinion on that?[/quote]

Never say never but a decent basal cortisol makes Addison's very unlikely http://avmajournals.avma.org/doi/abs/10.2460/javma.231.3.413

Re: Diabetes insipidous?? or renal failure (7 months old)

Holly Lee — Tue, 29 Oct 2013 16:11:48 GMT

Thanks both for your replies,

Liver enzymes, bilirubin, protein levels etc were all normal on the initial bloods, not done bile acids - cost is an issue and no other signs of shunt clinically.

I was of the understanding that a baseline cortisol of >55nmol/l DID rule out addisons disease - anyone else any opinion on that?

No glucosuria, and UPC is normal as well which surprised me on assumption a congenital renal problem would be glomerular.

Was considering extending the course of antibiotics in case any renal infection but would not expect a pyelonephritis in such a well, non pyrexic dog. Planning to ultrasound kidneys with my limited skills, referral not really an option and I would struggle to justify a renal biopsy.

All further thoughts welcomed!

Re: Diabetes insipidous?? or renal failure (7 months old)

Martin Atkinson — Tue, 29 Oct 2013 15:04:46 GMT

Hepatic shunt, OK BUN should be low but have you done liver profile? You can't rule out Addisons on a baseline cortisol you need an ACTH stim test although if you can't get Synacthen that may be tricky, I've seen it in a pup this age. You haven't mentioned glucose, presume no glycosuria but have you tested urine - Fanconi syndrome? DI is rather over-diagnosed but very rare, you need a water deprivation test which is not for the faint hearted but again wouldn't expect raised BUN/Crea. Agreed renal ultrasound probably next then biopsy if you/they want to go that far.

Re: Diabetes insipidous?? or renal failure (7 months old)

Kirsten Simpson — Tue, 29 Oct 2013 14:24:17 GMT

From the history and bloods and the knowledge that there are some strains of Boxer around that carry hereditary Juvenile Renal Disease, i'd be happy with the diagnosis of CRF. DI is a disease of rule out iirc and with bloods like that, would not be higher up my list. Refer her for an ultrasound to scan her kidneys?