Pupd dog with high ALKP but negative cushings tests

Re: Pupd dog with high ALKP but negative cushings tests

John Flynn — Thu, 26 Jun 2014 19:09:27 GMT

I'd be thinking either cholestatic liver disease or neoplasia more than cushings?

There's an 'old-fashioned' test for steroid-induced ALKP isoenzyme which is pretty cheap (£20ish) and could be requested from the lab on the sample already submitted (the fasted one pre dex/ACTH administration). Probably not much use, but if the level of ALKP that is the steroid-induced isoenzyme is very low and the high ALKP was your main reason for continuing to pursue a diagnosis of cushings, then it might help you change track?

Survey xrays not forgetting to look at the bones wouldn't do much harm, nor would abdominal ultrasound concentrating on liver area, but if owner not keen, then perhaps just monitor weight in a month?

Re: Pupd dog with high ALKP but negative cushings tests

Neil Wheadon — Thu, 26 Jun 2014 17:25:12 GMT

[quote user="Robin Grimmer"]Generally large dogs are more likely to have adrenal dependent Cushings[/quote]

Thanks Robin

I typed this the wrong way round and have corrected it

Neil

Re: Pupd dog with high ALKP but negative cushings tests

Robin Grimmer — Thu, 26 Jun 2014 17:18:31 GMT

Generally large dogs are more likely to have adrenal dependent Cushings, which can sometimes be tricky to diagnose. I would go for an abdominal ultrasound by someone who is good at it.

Re: Pupd dog with high ALKP but negative cushings tests

Neil Wheadon — Thu, 26 Jun 2014 17:04:06 GMT

A quiet 10 minutes so fishing about on the internet

This looks a well informed site http://www.newmanveterinary.com/Cushings.html

I was thinking, 11 year old Malamute, Cushings would be a rarer diagnosis, however the statistics here suggest that breed makes no difference for adrenal dependant as opposed to pituatory dependant being far less common in larger breeds

Cornell https://ahdc.vet.cornell.edu/sects/clinpath/modules/chem/alkphos.htm also has a few good ideas about increased ALKP

Hope these help

Neil

Re: Pupd dog with high ALKP but negative cushings tests

HollyK — Thu, 26 Jun 2014 16:09:19 GMT

Thank you both very much for your replies. The dog had no protein on his dipstick but i have not done a UPCR and we have not checked blood pressure. Out of interest does the 17-OH-progesterone test have a high incidence of false positives (ie. do i have to be really suspicious of cushings before running this test?!).

The owner is a human doctor and said in people with a high alkp she would be chasing metastatic neoplasia - is this something seen in dogs as it was not something i had particularly heard of?

Re: Pupd dog with high ALKP but negative cushings tests

Andrew Kent — Thu, 26 Jun 2014 10:49:02 GMT

Hi Holly,

If you think the dog's clinical signs are consistent with Cushing's then there may be some other things that you could look at. You could ask the lab to run 17-OH-Progesterone on your ACTH sample in case this is an atypical case. Equally an abdominal ultrasound might help to look at adrenal size, appearance of liver etc. Is the dog proteinuric or hypertensive?

Otherwise it is always a very difficult call as to whether we perform lots more investigations in a largely asymptomatic dog with raised ALP and we tend to decide depending on the owner. The other groups of causes you would be considering would be - cholestatic diseases (often has other accompanying bloods but not always), induction by drugs/hormones, increased osteoblastic activity (bone tumours etc). So other imaging - abdominal ultrasound +/- x-rays could be a good plan if owner wants.

Andy

Re: Pupd dog with high ALKP but negative cushings tests

Martin Atkinson — Thu, 26 Jun 2014 10:48:09 GMT

LDDS test is more reliable IME than ACTH stim test which is just as well currently! So it will be interesting to see the result, However I would perform some more specific liver tests like ALT, bile acids, CK and GGT +/- some imaging. I'd still put my money on Cushings here though.

First vet should be shot though.