Accuracy of ACTH test with liver and pancreas disease

[LaurieW]

Hello,

Can an ACTH test be thrown off by chronic liver disease and/or chronic pancreatitis?

I have an older Pomeranian type dog who was rescued from an exit ramp on a major metropolitan highway about 3 years ago. His name is Stewie and he is the best dog, and I am so lucky to have him in my life.

We have been battling chronic active hepatitis (chronic cholangitis/microvascular dysplasia via liver biopsy 2009) plus chronic pancreatitis. He had a short history ~ 4 months of diabetes in 2008/2009, thought to be from prednisone use. Seemed to resolve, then another episode of pancreatitis in Dec 2010. Back on insulin Dec 2010, everything going great until March 2010 when blood glucose is off the charts.

Having trouble regulating glucose. ALP is over 1500, GGT is also high, and cPLI is climbing back up into the high 400's.

Vet (IMS) suspects insulin resistance and/or cushings. She is reluctant to test for cushings right now, because of the other values. Wants to do another abdominal ultrasound to look at the adrenals. Several past ultrasounds have not indicated any abnormality, even when Stewie is very sick.

Have any of you had experience with an ultrasound helping to rule out, or rule in, cushings?

Patty from the K9Diabetes Forum suggested I post you about the liver, pancreas values and how they might affect the ACTH test.

Thank you,
Laurie and Stewie

[Harley PoMMom]

Most definitely, the ACTH stimulation test may be abnormal in dogs with non-adrenal illnesses.

If it were me, I would go with the ultrasound. I feel the ultrasound is one of the most useful diagnostic tools, especially considering it's non-invasive. There is no other tool that can provide so much info and an "inside look" so simply.

The U/S is used to evaluate the size and shape of the adrenals, and check for symmetry. If bilaterally normal-sized or large adrenals are visualized in a dog diagnosed as having Cushing's, this is considered strong evidence of Cushing's due to PDH. If one, large, irregular and/or invasive adrenal is visualized and the opposite is not seen, adrenal tumor may be suspected. If adrenal tumor is identified, it's an excellent screening test for hepatic or other organ metastasis, or invasion of the vena cava.

In addition, it evaluates the abdomen for any unexpected abnormalities urinary calculi, masses. It views the liver, gall bladder, etc; many Cushing's dogs have gall bladder sludge.

Not all ultrasounds are created equal. A good quality ultrasound/interpretation depends on a few things; the tool used, the technician performing it, and the physician interpreting it. There is a great difference in the quality of U/S machines. Is it a human grade (Phillips, GE, Siemens). My gen vet had an old (? brand) that just doesn't have the power to capture crisp, high-resolution images.

Some studies are technically difficult anyway, and that accompanies with a poorer quality tool, results in a poorer image. The technician: most will perform their own and therefore, it should those most experienced with capturing good windows and images. That would be a board certified radiologist or board certified Internal Med Spec. Likewise the one interpreting it should be the most experienced as well, and that's one of the 2 above.

Hope this helps.

Love and hugs,
Lori

[Squirt's Mom]

Hi Laurie,

Welcome to you and Stewie! :)

I agree with Lori. An ultrasound saved my Squirt's life by finding a tumor on her spleen. Once it was removed, her cortisol returned to normal and has remained that way. Her's is a good case of a non-adrenal illness (an illness not related to Cushing's in any way) causing positive results on tests - she was positive on the LDDS, HDDS, ACTH, and UTK panel. Pancreatitis, kidney or liver disease, and many other things can affect an ACTH.

Bless you for saving this little guy's life and giving him such a loving home. He is a lucky fellow!

Hugs,
Leslie and the gang

[lulusmom]

Hi Laurie and welcome to the forum.

Could you please do us a favor and post the abnormal values on any bloodwork and urinalysis? Please include the normal reference ranges. I would think that if you are battling chronic hepatitis and pancreatitis, the ALT would be seriously elevated as well as the ALK.

Given Stewie's multiple issues, all of which can transiently elevate cortisol, the usual diagnostic tests (UC:CR, ACTH Stimulation and LDDS) can yield false positive results. I therefore concur with Leslie and Lori that an ultrasound would be more appropriate. Aside from the difficulty in regulating the diabetes, is Stewie showing any other symptoms associated with cushing's?

Glynda

[LaurieW]

Thanks to all of you for the quick and extremely helpful responses--I will schedule the US first thing tomorrow!

Lori, I don't know what kind of machine it is. But it will be at a referral center and they have several board-certified radiologists who perform and interpret the test.

Glynda, no copy of the bloodwork yet but here are the abnormalities I wrote down:

ALP >1500 (normal is 23-212)

GGT was high, didn't write down the number as no one ever seems to pay much attention to this enzyme

cPLI 479 (normal is under 200, over 400 is consistent with pancreatitis)

Cholesterol 325 (92-324)

Platelets elevated but they usually are

Thyroid values "low normal"

Urinalysis was basically normal

His ALT was normal , but that can vary for him.

The ALP has been over 2600 in the past. My last IMS (who has left the practice) always had cushings in the back of his mind.

He has polyuria/polydypsia, poor hair coat, some hair missing, flaky skin, muscle wasting especially in the hindlegs. But all of these things, including his lab values, can also be associated with the other disease processes he has.

Re-visiting cushings again because his BG keeps climbing even with more insulin.

Thanks again--you all have very cute dogs:)
Laurie