Addisons and Cushings?

Re: Addisons and Cushings?

Glenn Hodgson — Mon, 03 Mar 2014 21:27:28 GMT

Phone your vetoryl rep. They'll make sure you get your hands on some!

Re: Addisons and Cushings?

Glenn Hodgson — Mon, 03 Mar 2014 21:27:26 GMT

Phone your vetoryl rep. They'll make sure you get your hands on some!

Re: Addisons and Cushings?

Noweia — Mon, 03 Mar 2014 21:08:46 GMT

[quote user="Christopher Saul"]

Re the synacthen : it should now be available again.

[/quote]

We can't get it yet :(

Re: Addisons and Cushings?

Virginia Campbell — Mon, 03 Mar 2014 20:17:35 GMT

[quote user="Virginia Campbell"]if needed at all as you and John point out).[/quote]

Mark, sorry - not John! Sheesh.

Re: Addisons and Cushings?

Virginia Campbell — Mon, 03 Mar 2014 20:16:16 GMT

[quote user="Christopher Saul"]Addison's patients will be addisonian for ever. The condition occurs as a result of immune mediated attack on the adrenal cortices, which would be destroyed and therefore incapable of producing corticosteroids. These patients are insensitive to ACTH (and they will be producing lots of ACTH anyway) Hence a pituitary lesion would be incapable of inducing hyperadrenocorticism - pituitary dependent cushing's is impossible.[/quote]

Righto, hmm I should have worked that one out myself!

I was actually wrong about dosing of pred - going through the history, somebody else noticed that its haircoat was a bit thin 2.5 years ago and tapered its pred from 1mg sid to 0.5mg sid. The last lot of pred that went out had 1mg sid rather than half tab sid on by mistake. I'll check with the O what the dog is getting. Thanks for the info about the hydrocortisone. I've seen another long term Addisons patient that looks a bit Cushingoid lately, so might look into getting some in, as much for any new Addisonians that we diagnose as anything (if needed at all as you and John point out).

Re: Addisons and Cushings?

Christopher Saul — Mon, 03 Mar 2014 19:13:47 GMT

Hi Virginia

Addison's patients will be addisonian for ever. The condition occurs as a result of immune mediated attack on the adrenal cortices, which would be destroyed and therefore incapable of producing corticosteroids. These patients are insensitive to ACTH (and they will be producing lots of ACTH anyway) Hence a pituitary lesion would be incapable of inducing hyperadrenocorticism - pituitary dependent cushing's is impossible.

I guess it MIGHT be theoretically possible for a new adrenal tumour to develop, but I am not aware of any cases in the literature of a (functional at least) adrenal tumour ever developing in an addisonian patient.

So, oversupplementation/ iatrogenic cushing's is overwhelmingly more likely

hydrocortisone is a less potent glucocorticoid than prednisolone - around a quarter the potency of prednisolone - so it may be sensible to think about changing this wee dog onto hydrocortisone instead to more accurately titrate the glucocorticoid dose.

Fludrocortisone does have some glucocorticoid activity so she may not need any glucocorticoid on top of this at all of course (though many dogs do)

Re the synacthen : it should now be available again. However an ACTH stim will tell you nothing as

1) the prednisolone which the dog has been on will cross react with cortisol and make the test impossible to interpret.

2) ACTH stim is a test of adrenocortical reserve - and we know this dog has none (assuming the original diagnosis was correct).

Of course, there could be another reason altogether for the pot bellied appearance, and for this I would advise an abdominal ultrasound, but how much you want to pursue this depends upon finances etc - if they are limited and if dog and owner are happy................

hope this helps

Chris

Re: Addisons and Cushings?

Richard Carter — Mon, 03 Mar 2014 18:45:08 GMT

Continuous pred admin will cause iatrogenic HAC - you don't need to try confirm it.

The problem with doing any type of cortisol testing is that you will get the preds result back - when I last enquired at our lab how long the dog needed to be off any preds to test for genuine HAC, they recommended > 6 weeks.

Re: Addisons and Cushings?

Mark Holmes — Mon, 03 Mar 2014 18:35:06 GMT

I manage most if my Addison's dz dogs without additional pred, simply on florinef. I would be tempted to back off the pred and simply use florinef alone however there is an argument for leaving well alone. If the dog and owners are happy and the dog is 12 .....what's to be gained?