Barney and possible cushings?

[b&b]

Hi
I'm looking for some advice as my 14yo mixed breed terrier is having a CCR & LDDS today.

He started to display a few cushings symptoms approx 6 weeks ago:
panting
drinking and peeing
exercise intolerance
distended tummy

We took him to our regular vet where they did some blood work, his liver values & cholesterol came back high so they put him on destolit, denamarin & a weeks course of antibiotics.
They started banding around the cushings / liver failure / diagnosis so we asked to be referred to a IMS.
We were referred last week and he had a x ray and ultrasound.
The ultrasound revealed one adrenal gland is enlarged. Again the IMS said that cushings was a possibilty and that he needs further tests to try and rule it out as it is so hard to diagnose.
So today he is back at his regular vets for further tests.
He has had some further bloodwork done which has revealed significant improvements in his liver values (i don't have copies yet but will ask for some later today)
His clinical signs have also improved with his drinking and peeing back to normal and no panting.
I'm trying not to get my hopes up as the vet said that the clinical signs can come and go and that we may have caught it really early.
What I'm trying to understand is that even if the 2 tests come back negative today he may still have cushings? Because of the enlarged adrenal gland?
What sort of treatment is advised in this instance - where he shows no clinical signs?
Would removal of the adrenal gland be appropriate.

Thanks in advance for any advice or questions I should be asking my vets.

[labblab]

Hello and welcome to you and Barney!

The majority of Cushing's cases in dogs result from pituitary tumors, and in those instances it would be very unusual for overt symptoms to come and go if the disease is left untreated. A much smaller percentage of dogs suffer from adrenal tumors, and there is one rare type -- the pheochromocytoma -- that is often associated with intermittent symptoms that result from "bursts" of hormone overproduction. This type of tumor can cause the more traditional types of Cushing's symptoms such as excessive thirst and urination. But the greatest short-term dangers stem from blood pressure spikes and heart/stroke risks resulting from overproduction of epinephrine.

Enlargement of one adrenal gland does suggest the possibility of a tumor. If so, I would have hoped that the ultrasound would have provided some detailed visualization of an actual mass or growth. Was the IMS unable to report anything other than just that there was gland enlargement? It may be the case that additional imaging may be required to better identify the adrenal abnormality. If an adrenal tumor is present, the only permanent cure is to remove the adrenal gland. However, this type of surgery is a very expensive and very serious undertaking.

It will be very interesting to see how today's tests turn out. But if your dog does suffer from a pheochromocytoma, I believe it is indeed possible that today's tests that measure overproduction of cortisol may turn out negative. That is because it may be the intermittent overproduction of a hormone other than cortisol that is the basis for Barney's observable symptoms.

Please do let us know how these tests turn out and we'll go from there. But once again, welcome to you both.

Marianne

[b&b]

Hi
Thanks for your reply, sorry for the massive post but please see his discharge notes below:
Presenting complaint

Barney presented for further evaluation of his 3-4 week history of lethargy, increased respiration rate,abdominal distension, exercise intolerance and suspected PUPD (increased thirst and urination). He had afew episodes of vomiting over the past few weeks. He previously had a grade I/VI left apical murmur identified and Barney had been evaluated by a cardiologist after two episodes over collapse over the last 2 years. No primary cardiac cause was identified on investigations and vaso-vagal syncope was suspected.

More recently at your veterinary hospital biochemistry identified an increase in liver enzymes. Urinalysis had previously revealed various urine specific gravity readings from dilute to concentrated urine. Barney was placed on Amoxycillin Clavulanic acid (7 day course), Denamarin and Destolit in the week prior to referral. Since initiating therapy his PUPD had resolved.

Physical
Physical examination revealed an alert dog in good body condition (body condition score 3/5, body weight 14.6Kg). He was panting on examination. Thoracic auscultation revealed the previously identified grade I/VI holosystolic left apical murmur but was otherwise unremarkable. His abdomen was larger than it had been previously. The remainder of his examination was unremarkable.

Haematology

Within normal limits.

Serum biochemistry

A mild increase in liver enzymes. His liver enzymes had reduced in comparison to last month.

PT and APTT

Within normal limits.

Urinalysis (including urine cortisol to creatinine ratio)

Pending.

Thoracic radiography

The cardiovascular structures and pulmonary parenchyma are normal. Marked osteophytosis is present along the caudal aspect of both glenoids representing shoulder osteoarthritis.

Abdominal sonography

The liver was diffusely mildly hyperehcoic with a 0.4 cm hypoechoic nodule in the ventral right liver. The hepatic changes were though to represent a diffuse hepatopathy with a single nodule; suspected vacuolar change (fatty change). The left adrenal gland was enlarged (1.7 cm thick); the enlargement may represent primary adrenal neoplasia (such as an adenocarcinoma) or hyperplasia. The right adrenal gland was mildly enlarged (1.0 cm thick). The remainder of the ultrasound was within normal limits, likely representing hyperplasia.

Cytology (needle samples)

Liver- pending

Diagnosis

 Open

 Possible hyperadrenocortcism (HAC)

Treatment

 To continue on the previously prescribed Destolit 150mg tablet once daily and Denamarin 225mg tablet once daily.

Next re-examination

7 days @ Penmellyn Veterinary Group

Low dose dexamethasone suppression test

A baseline cortisol level (plain or heparin tube early in the morning) needs to be obtained and subsequently a low-dose dexamethasone suppression test is performed with 0.015 mg/kg of dexamethasone IV. Blood samples have to be collected 3-4 hours and 8 hours after administration of dexamethasone. These should be submitted to an external lab e.g. TDDS.

4 weeks @ CAVE VETERINARY SPECIALISTS

Discussion

Hyperadrenocorticism is a possibility given Barney’s clinical presentation combined with the imaging findings. The pending urine testing should provide us with further information. As you are aware, a diagnosis of hyperadrenocorticism is challenging due to the variability in clinical signs and diagnostic testing. There is no perfect diagnostic test and repeated testing / use of different tests is often needed.

Screening tests (will detect most cases of hyperadrenocorticism ie are very sensitive, but false positives possible with other illness); these tests include urine cortisol to creatinine ratio (UC;Cr) and Low dose dexamethasone suppression test (LDDST). The UC:Cr test is very sensitive i.e. almost all dogs with hyperadrenocorticism will have an abnormal value. It is important to bear in mind that it is very non-specific – in one study 76% of dogs with non-adrenal illnesses of various sorts had a raised UC:Cr. A positive LDDS test in conjunction with compatible clinical signs is strongly supportive of a diagnosis of HAC.

Another possibility for Barney is that he had an infectious focus which has responded to the previously prescribed antibiotics (ie: urinary tract infection). It is also possible that the cessation of his PUPD is an
incidental finding coinciding with therapy. If an infectious focus has subsequently resolved we would expect his clinical signs to resolve completely.

Diet and Exercise:

As previously

Results:

We expect the laboratory results to return in 3-5 working days, and we will call you to discuss them. Please call us if you have not heard from us by 10 days following discharge. Once we have the results, we can discuss whether any further treatment is required, and when we would recommend further check-ups.

[labblab]

He previously had a grade I/VI left apical murmur identified and Barney had been evaluated by a cardiologist after two episodes over collapse over the last 2 years. No primary cardiac cause was identified on investigations and vaso-vagal syncope was suspected.

Thanks so much for all this additional info and I will be looking through it more closely later today. This comment really caught my eye, though, because unexplained collapse has been reported to us by other owners here whose dogs suffered from pheos. Again, this is an intermittent problem because the abnormal hormone release can occur in bursts that avoid detection at other times. When you talk to the vet, I'd encourage you to ask about the possibility of a pheochromocytoma given the intermittent symptom profile and Barney's history of unexplained collapse.

Marianne

[labblab]

Here, take a look at this info...

Clinical signs associated with pheochromocytoma are often vague and intermittent, and may mimic more common disorders such as hyperadrenocortisism, diabetes mellitus, hepatic or renal disease, or other neoplasms. Clinical signs frequently observed include weakness, collapse, lethargy, anorexia, vomiting, panting, weight loss, anxiety, restlessness, polyuria, polydipsia, diarrhea, abdominal distention, hind limb edema, epistaxis, seizures or acute blindness. The clinical signs are generally associated with catecholamine excess and systemic hypertension. Elevation of blood pressure induced by sudden release of catecholamines can precipitate acute congestive heart failure, pulmonary edema, myocardial infarction, ventricular fibrillation and cerebral hemorrhage. Nonfunctional tumors can also produce clinical signs by their space occupying nature.

Pheochromocytomas occasionally result in secondary conditions including invasion and thrombosis of the caudal vena cava, aortic thromboembolism, spontaneous rupture of the tumor, paresis secondary to spinal cord compression, arrhythmias, cardiac hyper-trophy, arteriolar sclerosis, systemic hyper-tension, or hyperadrenocortisism. About 15-38% of pheochromocytomas invade the caudal vena cava, causing clinical signs of ascites, hind limb edema, or distention of the caudal epigastric veins. Ultrasound and Doppler imaging can be used to identify obstruction of the caudal vena cava. Aortic thrombo-embolism is fairly uncommon in dogs, and occurs due to endothelial damage, vascular stasis, and hypercoagulable states. Rarely, pheochromocytomas may rupture spon-taneously and cause retroperitoneal hemorrhage or periumbilical ecchymoses (Cullen's sign). Systemic hypertension occurs in 43-70% of canine patients with pheo-chromocytoma, and concurrent hyperadreno-cortism has been found in 12% of reported cases.

[b&b]

So..I've spoken to the IMS today.
Barneys' CCR & LDDS both came back indicating that cushings is not likely.
His clinical signs have resolved. They said it could be a incidental adrenal mass but they would like to perform a metanephrines?(sp) blood test with a ultrasound in 8 weeks, would you agree?
Thanks in advance
Bonnie

[labblab]

That sounds like a good game plan to me, as it sounds as though the IMS is actually considering the possibility of an adrenal pheochromocytoma. I believe the blood test they are talking about is designed to test for the abnormal release of certain hormones by a pheo. Here's a link to a description of the blood test as it relates to humans; I'm guessing the canine test is comparable.

https://labtestsonline.org/understan...rine/tab/test/

Please do let us know how things progress, including whether or Barney's symptoms recur again.

Marianne

[b&b]

Are there any threads on the forum where the dog has pheos?
Bonnie

[labblab]

Yes, even though the condition is rare, we have had several dogs here with pheos. If you click on the "Search" button in the menu at the top of every page, and then type in "pheochromocytoma," you'll find a listing of threads within which it is mentioned. But in the meantime, here are a couple of threads to get you started.

http://www.k9cushings.com/forum/showthread.php?t=4242

http://www.k9cushings.com/forum/showthread.php?t=6578

Marianne

[b&b]

Barney had a follow up ultrasound at the IMS yesterday. Because he has been symptom free for the last 8 weeks they didn't do the pheo blood test or any cushings tests.
The ultrasound showed the adrenal mass is unchanged.
She thinks it is likely that it is jsut an incidental finding & has recommended another ultrasound in 6 months or to go back sooner if he displays any cushings symptoms.