Carmel T. Mooney, MVB, Mphil, PhD, DECVIM-CA, MRCVS
University Veterinary Hospital, School of Agriculture, Food Science & Veterinary Medicine
Canine hyperadrenocorticism can be challenging to diagnose. Many of the clinical and clinicopathological abnormalities are shared by a variety of other disorders and of the numerous adrenal function tests recommended, no true gold standard exists. There is a wide variation in veterinary input, invasiveness, time and cost between the tests and each differs significantly with regard to diagnostic sensitivity, specificity and efficiency. Some of the tests are capable of differentiating the site of the lesion while others may be useful in monitoring the response to therapy. Interpretation of test results in individual patients requires knowledge of its characteristics and what it is assessing.
First Steps in Test Selection
Whatever test is chosen to investigate hyperadrenocorticism, it is important that it is being carried out in an animal likely to have the disorder and one in which concurrent confounding medications are not being used. This serves to increase the prevalence of the disorder in the population under test and will significantly positively influence the diagnostic performance of each test. Hyperadrenocorticism is a disease of middle-aged to older dogs of either sex. Small breed dogs appear predisposed to pituitary-dependent hyperadrenocorticism (PDH) while the likelihood of functional adrenal tumours (AT) increases particularly in larger dogs (>20 kg). Numerous clinical signs are possible but most commonly include polyuria/polydipsia, polyphagia, abdominal distension and a variety of dermatological abnormalities. Pathognomonic features, such as calcinosis cutis, are unusual and as likely in iatrogenic as in naturally occurring hyperadrenocorticism. Routine clinicopathological abnormalities include mild erythrocytosis, a stress leucogram, dilute urine, increased liver enzymes (with a disproportionate increase in alkaline phosphatase), hypercholesterolaemia, hypertriglyceridaemia and increased bile acids. Although these abnormalities are not specific for hyperadrenocorticism, almost all cushingoid dogs have at least one abnormality.
Adrenocorticotropic Hormone Response Test
The adrenocorticotropic hormone (ACTH) response test serves to demonstrate functional adrenal reserve following administration of a pharmacological dose of ACTH. It is generally used to screen for the presence of hyperadrenocorticism. It can distinguish between iatrogenic and spontaneous hyperadrenocorticism but does not reliably distinguish between PDH and functional AT. It is useful in the monitoring of adrenocorticolytic and trilostane therapy. Although cortisol is the main hormone measured, other precursors can be assayed for investigation of sex hormone imbalance and non-cortisol producing tumours.
The ACTH response test is a simple and quick procedure easily performed in the practice environment. The standard protocol is measurement of circulating cortisol concentration before and one hour after a single intramuscular or intravenous injection of synthetic ACTH (tetracosactrin, cosyntropin) at 250 μg/dog, although doses as low as 1.0 µg/kg can be used.
Dogs with hyperadrenocorticism theoretically have an exaggerated response to ACTH. The absolute post-ACTH cortisol concentration is most frequently used to assess the response during an ACTH stimulation test. Although values above the reference range are frequently cited as abnormal, most clinicians use a value that significantly exceeds this range, often between 600 and 650 nmol/l. Approximately 80% of dogs with PDH have an exaggerated cortisol response to ACTH while only approximately 60% of dogs with AT have such results. Despite the low sensitivity of this test, an advantage is that it is highly specific (approximately 0.9) and has a relatively high positive predictive value. The likelihood of an abnormal result in a non-cushingoid dog generally increases the more severely or chronically ill the animal is. Occasionally, dogs with AT have a subnormal cortisol response to exogenous ACTH.
In conclusion, an abnormal cortisol response in a dog with suspicious clinical and clinicopathological features is supportive of hyperadrenocorticism but provides no information on the site of the lesion. Although abnormal results can occur particularly in an animal known to have concurrent non-adrenal illness (e.g., unstable diabetes mellitus), a more common diagnostic dilemma is finding a reference range (or rarely subnormal) cortisol response in a highly suspicious case. Decreasing the post ACTH cortisol cut-off point (e.g., to approximately 500 nmol/l) for hyperadrenocorticism improves the test sensitivity with minimal effect on specificity and helps improve the diagnostic performance of this test. Alternatively, a more sensitive diagnostic test should be considered in these suspicious cases.
Low-Dose Dexamethasone Suppression Test
In healthy dogs, glucocorticoids exert negative feedback inhibition on ACTH secretion. A low dose of dexamethasone (0.01-0.015 mg/kg) administered intravenously to healthy dogs, causes inhibition of ACTH secretion and reduced plasma cortisol concentrations within 2 to 3 hours lasting up to 8 hours. In hyperadrenocorticism, the 8-hour cortisol value is not sufficiently suppressed and remains above approximately 30 to 40 nmol/l. The low-dose dexamethasone suppression (LDDS) test is considered extremely sensitive for hyperadrenocorticism. In approximately 95% of dogs with PDH and up to 100% of dogs with AT, cortisol suppression is inadequate. However, a small number of dogs with hyperadrenocorticism have suppressed values at 8 hours and suppressed or occasionally elevated (inverse results) values at 3 or 4 hours. However, the greatest problem with the test is that false-positive results frequently occur in dogs with non-adrenal disease with a reported specificity as low as low as 0.44. In general, the more severe the non-adrenal illness, the more likely that cortisol suppression is inadequate. On the other hand, the high negative predictive value of this test means that hyperadrenocorticism is unlikely if normal cortisol suppression occurs.
An additional value in performing a LDDS test is its ability to distinguish between PDH and AT in up to 60% of cases when circulating cortisol concentrations are measured at 3 or 4 and at 8 hours. Criteria that indicate a diagnosis of PDH include a decrease of circulating cortisol concentration to less than a laboratory reference value at 3 or 4 hours, less than 50% of the baseline value at 3 or 4 hours, or less than 50% of the baseline value at 8 hours. However, PDH cannot be ruled out if such suppression does not occur.
The LDDS test cannot be used to evaluate response to therapy for hyperadrenocorticism.
Urinary Cortisol:Creatinine Ratio
The determination of the cortisol (corticoid) : creatinine ratio (UCCR) in urine samples taken in the morning can be used in the investigation of hyperadrenocorticism in dogs. It is the least stressful of all the diagnostic tests as owners can obtain samples in the home environment. It is also extremely sensitive, with a reported range of 0.75 to 1.0. However, it lacks specificity with values as low as 0.21 especially if the animal is stressed or concurrent moderate to severe non-adrenal illness is present. Overall, its high negative predictive value suggests that hyperadrenocorticism is unlikely if the UCCR is within the reference range but that further investigation for hyperadrenocorticism is warranted if it is elevated.
Extremely elevated UCCR values occur almost exclusively in PDH. Suppression to greater than 50% of baseline following oral administration of three doses of dexamethasone (0.1 mg/kg) is similarly consistent with PDH. Overall, it is considered an inappropriate test for accurate monitoring of adrenocorticolytic therapy.
Measurement of 17α-Hydroxyprogesterone
Within the adrenal gland, 17-α-hydroxylase catalyses the conversion of pregnenolone to 17α-hydroxyprogesterone (17-OHP). It is ACTH responsive and 17-OHP is further metabolised by 21-hydroxylase and 11-β-hydroxylase to produce 11-deoxycortisol and cortisol, respectively.
Its measurement has proven useful in the investigation of dogs with AT that have a subnormal cortisol response to exogenous ACTH. In these individual (and rare) cases, the adrenal gland presumably retains the ability to respond to ACTH but cortisol production is not intact.
Recent research has suggested that measurement of 17-OHP is also useful particularly in dogs with clinical and clinicopathological signs suggestive of hyperadrenocorticism that do not exhibit classical results using traditional tests, although this is unusual. However, because of the overlap in test results between healthy and sick dogs and those with hyperadrenocorticism, it cannot be advocated as a routine screening test for hyperadrenocorticism.
A variety of other sex hormones can potentially be measured during an ACTH response test but the interindividual variation in results limits their value in investigating hyperadrenocorticism.
Plasma Adrenocorticotropic Hormone Concentration
Measurement of circulating ACTH concentration is an excellent test to discriminate between PDH and AT but has no role to play in the diagnosis of the condition. Dogs with PDH release large amounts of ACTH but dogs with AT have reduced ACTH output. In dogs, inappropriately elevated plasma ACTH concentrations are consistent with PDH while low values are consistent with AT. Meticulous sample handling procedures (cold collection and immediate freezing) are necessary to avoid degradation and falsely low values. Aprotinin has a profound preservative effect upon canine plasma ACTH and it may be possible to submit unfrozen plasma samples to which aprotinin has been added.
Ultrasonography is the most widely available useful imaging method for assessing dogs with hyperadrenocorticism. However, like endogenous ACTH measurement, abdominal ultrasonography is most valuable in distinguishing PDH from functional AT. As a screening test it has limitations because of the overlap in adrenal gland size between healthy and sick dogs and those with PDH, and because unilateral adrenal gland enlargement may represent incidental non-functioning adrenal tumours or those capable of producing other hormones. Co-existing PDH and AT has been described in a few cases of hyperadrenocorticism. In such cases, the results of the adrenal function tests and endogenous ACTH measurement are at variance with the ultrasonographic appearance of the adrenal glands.
Whilst hyperadrenocorticism is undoubtedly difficult to diagnosis, selecting appropriate cases significantly increases the diagnostic performance. It serves to minimise inappropriately diagnosing hyperadrenocorticism in dogs with non-adrenal illness and to have confidence to consider more diagnostic tests in animals highly suspicious of the disorder but with one negative test result.
If finances allow, the selection of a highly specific test with one of high sensitivity maximises diagnostic performance. In our clinic, the ACTH response test and low dose dexamethasone suppression test are recommended in all suspicious patients. The simultaneous measurement of 17-OHP during the ACTH response test is not considered routinely but is reserved for investigation of animals with suspicious clinical signs and a subnormal response to ACTH administration. Measurement of endogenous ACTH concentration and diagnostic imaging are most useful in distinguishing between PDH and AT.
1.Chapman PS, Mooney CT, et al. Evaluation of the basal and post-adrenocorticotropic hormone serum concentrations of 17-hydroxyprogesterone concentrations for the diagnosis of hyperadrenocorticism in dogs. Veterinary Record 2003; 153: 771-775.
2.Gould SM, Baines EA, et al. Use of endogenous ACTH concentration and adrenal ultrasonography to distinguish the cause of canine hyperadrenocorticism. Journal of Small Animal Practice 2001; 42: 113-121.
3.Herrtage ME. Canine hyperadrenocorticism. In: Mooney, CT and Peterson, ME. eds. Manual of Canine and Feline Endocrinology (third edition). BSAVA Publications, 2004; 150-171.
4.Kaplan AJ, Peterson ME, Kemppainen RJ. Effects of disease on the results of the diagnostic tests for use in detecting hyperadrenocorticism in dogs. Journal of the American Veterinary Medical Association 1995; 207: 445-451.
5.Norman EJ, Thompson H, Mooney CT. Dynamic adrenal function testing in eight dogs with hyperadrenocorticism associated with adrenocortical neoplasia. Veterinary Record 1999; 144: 551-554.
How do you read ACTH stimulation test results in dogs? ›
Test interpretation (dogs): Post-ACTH cortisol values >550 nmol/L usually indicate hyperadrenocorticism. Post-ACTH cortisol values of 470-550 nmol/L are equivocal. Post-ACTH cortisol values <470 nmol/L suggest normal adrenocortical function.How do you test for a hyperadrenocorticism in dogs? ›
Screening tests designed to diagnose hyperadrenocorticism include the corticotropin (adrenocorticotropic hormone; ACTH) stimulation test, low-dose dexamethasone suppression test, and the urinary cortisol:creatinine ratio.What is normal post ACTH cortisol dog? ›
In normal dogs, pre ACTH cortisol concentrations are usually between 20 and 250 nmol/l with post ACTH cortisol concentrations between 200 to 450 nmol/l.What is the reference range for ACTH in dogs? ›
|Dogs with Hypoadrenocorticism||Healthy Dogs|
|Baseline cortisol (μg/dL)||<0.2–2||0.6–12|
Cortisol level after ACTH stimulation should be higher than 18 to 20 mcg/dL or 497 to 552 nmol/L, depending on the dose of ACTH used. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens.
What Abnormal Results Mean. A higher-than-normal level of ACTH may indicate: Adrenal glands not producing enough cortisol (Addison disease) Adrenal glands not producing enough hormones (congenital adrenal hyperplasia)What lab values indicate Cushing's disease in dogs? ›
In most dogs with Cushing's, cortisol production after injection of synthetic ACTH is much increased, and for the majority of cases a 1 hour cortisol value of greater than 550 - 600 nmol/l will be seen.What is the most common abnormality seen on a biochemistry panel in a dog with hyperadrenocorticism? ›
On the biochemistry panel, the most consistent finding is increased alkaline phosphatase (ALP) activity.How do you test for hyperadrenocorticism? ›
The low dose dexamethasone suppression test is a good test for diagnosing hyperadrenocorticism in most cases. It is relatively inexpensive to perform, and tests the response of the pituitary and adrenal glands to negative feedback inhibition.What level of cortisol is considered Cushing's? ›
The 24-hour urinary cortisol test measures the amount of cortisol being produced within the urine over the course of an entire day. Levels higher than 50-100 micrograms per day in an adult suggest the presence of Cushing's syndrome.
Do high cortisol indicate a dog has Cushings? ›
The urine cortisol/creatinine ratio is usually elevated with Cushing's disease. However, stress and other illnesses may also increase this ratio. While a high urine cortisol/creatinine ratio suggests Cushing's disease, it cannot confirm the diagnosis.What are the symptoms of too much ACTH? ›
- Upper body obesity.
- Round face.
- Increased fat around neck or a fatty hump between the shoulders.
- Thinning arms and legs.
- Fragile and thin skin.
- Stretch marks on abdomen, thighs, buttocks, arms, and breasts.
- Bone and muscle weakness.
- Severe fatigue.
A higher-than-normal level of ACTH may indicate: Adrenal glands not producing enough cortisol ( Addison disease ) Adrenal glands not producing enough hormones ( congenital adrenal hyperplasia ) One or more of the endocrine glands are overactive or have formed a tumor ( multiple endocrine neoplasia type I )Is ACTH high or low in Cushing's? ›
Cushing disease occurs when a benign tumor in the pituitary gland causes the pituitary gland to produce too much ACTH, the hormone responsible for cortisol production. Too much ACTH in the body causes the adrenal glands to produce cortisol in high levels.Does high ACTH mean high cortisol? ›
The pituitary secretes adrenocorticotropic hormone (ACTH), which travels to the adrenal glands and stimulates them to grow and produce cortisol. Too much ACTH can cause high levels of cortisol in the body and, in turn, Cushing syndrome.What lab values indicate adrenal insufficiency? ›
An increase of less than 9 mcg/dL is considered diagnostic of adrenal insufficiency.What is the gold standard test in evaluating cortisol deficiency? ›
The short corticotropin test (also called the adrenocorticotropic hormone [ACTH] stimulation test) administered with a 250 μg dose is considered the gold standard test to confirm a diagnosis of primary adrenal insufficiency (PAI).What does a high cortisol test mean? ›
A gland in your brain, called the pituitary gland, makes a hormone that tells your adrenal glands how much cortisol to make. If your cortisol levels are too high or too low, it may mean you have a disorder of your adrenal glands, a problem with your pituitary gland, or a tumor that makes cortisol.What is the normal range for ACTH levels? ›
Normal values — Plasma corticotropin (ACTH) concentrations are usually between 10 and 60 pg/mL (2.2 and 13.3 pmol/L) at 8 AM.What is the level of ACTH in Addison's disease? ›
ACTH levels often are elevated to higher than 250 pg/mL in patients with Addison disease.
What lab values change with Cushing's disease? ›
A plasma cortisol level exceeding 1.4 μg per L (40 nmol per L) is considered positive for Cushing's syndrome. This test is nearly 100 percent sensitive and specific for Cushing's syndrome.What is the best single test to confirm Cushing's syndrome? ›
24-hour urinary free-cortisol test
In this test, you will collect your urine over a 24-hour period. Your health care professional will send your urine sample to a lab to test cortisol levels. Higher than normal cortisol levels suggest Cushing's syndrome.
- The most common signs seen with hyperadrenocorticism include excessive urination, excessive drinking, increased appetite, hair. loss, muscle weakness, a “potbellied” appearance, panting, thin skin and lethargy. ...
- Cushing's Disease can only be diagnosed using blood tests.
The increased appetite is a direct result of elevated levels of cortisol, which stimulate appetite. Lethargy (drowsiness or lack of activity) and a poor hair coat are also common in pets with hyperadrenocorticism. "Many dogs with Cushing's disease develop a bloated or pot-bellied appearance."What is the best test for Cushings in dogs? ›
Low-Dose Dexamethasone-Suppression Test (LDDST) measuring Cortisol. This is the preferred test for the initial diagnosis of Cushing's syndrome.How accurate is the ACTH stimulation test in dogs? ›
For dogs suspected of having hypoadrenocorticism, the ACTH‐stimulated cortisol concentrations in response to both doses of ACTH were equivalent (90% confidence interval [CI], 80.5‐97.2%; P = . 04).What is ACTH test for Cushing's disease in dogs? ›
An ACTH stimulation test takes 1 hour to perform: a blood sample is taken, a small amount of synthetic ACTH hormone is injected and another blood sample is taken 1 hour later. Cortisol levels are obtained and if the second cortisol is elevated Cushing's Disease is diagnosed.What is a good cortisol creatinine ratio for dogs? ›
UCCR. The median UCCR was 0.65 × 10−6 (0.33‐1.22 × 10−6), 10.28 × 10−6 (2.46‐78.65 × 10−6), and 3.38 × 10−6 (1.11‐17.32 × 10−6) in dogs with HA, dogs with DMHA and healthy dogs, respectively. The median UCCR was significantly lower (P < .What is the gold standard test for Cushing's? ›
Bilateral Inferior Petrosal Sinus Sampling
This is the "gold standard" test for distinguishing between Cushing's disease and an ectopic source of ACTH. The procedure involves placement of sampling catheters in the inferior petrosal sinuses that drain the pituitary.
Three first-line diagnostic tests are currently used to screen for CS: measurement of free cortisol in 24-hour urine (UFC), cortisol suppressibility by low doses of dexamethasone (DST), and assessment of cortisol circadian rhythm using late-night serum and/or salivary cortisol.
What are the 4 underlying causes of Cushing's syndrome? ›
- A pituitary gland tumor (pituitary adenoma). ...
- An ACTH -secreting tumor. ...
- A primary adrenal gland disease. ...
- Familial Cushing syndrome.
Some of these symptoms, such as drinking and urinating excessively, mimic other diseases such as diabetes, kidney disease, urinary tract infections, etc.How do dogs with Cushings behave? ›
Aggression, increased pursuance of food and water, exercise intolerance, lethargy, and difficulty moving around in their day-to-day environments (navigating stairs, going up onto elevated surfaces, etc.) are some of the behavior changes commonly seen in dogs afflicted by Cushing's disease.What dog breeds are more prone to Cushings? ›
The overuse of steroids causes some cases of Cushing's. Female dogs are more prone to adrenal tumors than male dogs, and poodles, dachshunds, and Boston terriers are diagnosed with Cushing's more than other dog breeds.What organ is affected by ACTH? ›
Corticotropin-releasing hormone (CRH) is released from the hypothalamus, which stimulates the anterior pituitary to release adrenocorticotropic hormone (ACTH). ACTH then acts on its target organ, the adrenal cortex.What muscle is weak in Cushing's syndrome? ›
Muscle loss and weakness — Prolonged Cushing's syndrome causes the muscles of the shoulder and thighs/hips to become weaker. Some individuals notice that it becomes more difficult to get out of a chair or climb stairs because of the upper leg weakness.What is the treatment for Hyperadrenalism? ›
Treatment of hyperadrenalism will vary depending on which hormone is creating the problem as well as its underlying cause and the severity of the symptoms. Some patients respond well to medications that slow the hormone production, while others may surgery to remove one of the adrenal glands.Does anxiety increase ACTH? ›
In response to stress, cerebral cortex signaling stimulates the hypothalamus to release corticotropin-releasing hormone (CRH). In turn, CRH stimulates the pituitary gland to produce and release adrenocorticotropic hormone (ACTH) into the blood.Does stress cause high ACTH? ›
Stress also stimulates adrenocorticotropic hormone production and the resulting increase in cortisol levels. If there are any issues with your hypothalamus, pituitary gland or adrenal glands, it can affect the balance of hormones involved in this process, including ACTH.What does a low ACTH test mean? ›
A decline in the concentration of ACTH in the blood leads to a reduction in the secretion of adrenal hormones, resulting in adrenal insufficiency (hypoadrenalism). Adrenal insufficiency leads to weight loss, lack of appetite (anorexia), weakness, nausea, vomiting, and low blood pressure (hypotension).
What organs does Cushing's disease affect? ›
Cushing disease is a condition in which the pituitary gland releases too much adrenocorticotropic hormone (ACTH). The pituitary gland is an organ of the endocrine system.How do you read cortisol stimulation results? ›
A negative (normal) result occurs if the cortisol level is stimulated to greater than 500 to 600 nmol/L.  A positive (abnormal or subnormal) result can be from primary or central AI and can be further evaluated by ACTH levels. ACTH level is expected to be high with primary and low with central AI.What is the normal range for ACTH and cortisol? ›
Normal ranges for ACTH are fairly broad and like cortisol levels are time-dependent. They also vary from assay to assay. A typical normal range for an 8AM sample using the new assays is 10 to 50 picograms per milliliter (pg/ml); levels are usually less than 20 pg/ml at 4 PM and less than 5-10 pg/ml at midnight.What is ACTH to cortisol ratio for Cushings? ›
Conclusion: An ACTH/cortisol ratio >2.5 would be beneficial to diagnose CD together with other diagnostic tests. It is a simple test with no additional cost. Higher ratios might be related with larger, invasive, and atypical adenoma and also might be helpful to predict recurrence.What is a normal response to Cosyntropin stimulation test? ›
What are normal results for an ACTH stimulation test? Under normal circumstances, your cortisol levels should increase after synthetic ACTH stimulation. In a normal result, your cortisol level after ACTH stimulation should be higher than 12.6 micrograms per deciliter (mcg/dL).What cortisol levels indicate Cushing's in dogs? ›
In most dogs with Cushing's, cortisol production after injection of synthetic ACTH is much increased, and for the majority of cases a 1 hour cortisol value of greater than 550 - 600 nmol/l will be seen.What is the normal range for a canine PT value? ›
Normal PT in dogs is less than 22 seconds, but this can vary from laboratory to laboratory. Values greater than 22 seconds indicate a potential bleeding disorder. The most common cause of a prolonged PT is poisoning with an anticoagulant rodenticide.What lab values are elevated with Cushing's disease in dogs? ›
The urine cortisol/creatinine ratio is usually elevated with Cushing's disease. However, stress and other illnesses may also increase this ratio. While a high urine cortisol/creatinine ratio suggests Cushing's disease, it cannot confirm the diagnosis.What does normal ACTH and high cortisol mean? ›
ACTH-independent refers to normal ACTH levels accompanied by high cortisol levels. Either overactive adrenal glands or an adrenal tumor secreting cortisol may cause this condition.What is the cutoff for ACTH stimulation test? ›
We recommend a threshold of 14.6 μg/dL for the level of cortisol at 60 minutes after ACTH stimulation for the Abbott assay. In comparison with the historical threshold of 18 μg/dL, the application of the new cutoff may significantly decrease false-positive results due to ACTH stimulation testing.
What lab value is elevated in Cushing's? ›
The 24-hour urinary cortisol test measures the amount of cortisol being produced within the urine over the course of an entire day. Levels higher than 50-100 micrograms per day in an adult suggest the presence of Cushing's syndrome.What are the neurological signs of Cushing's in dogs? ›
About 20% of dogs with PDH eventually develop an expanding pituitary tumor, clinical signs include lethargy, behaviour changes, nervousness, anorexia, weight loss, circling, ataxia, disorientation, head pressing, seizures, stupor.What is the best test for Cushing's disease in dogs? ›
Low-Dose Dexamethasone-Suppression Test (LDDST) measuring Cortisol. This is the preferred test for the initial diagnosis of Cushing's syndrome.What does high PCT mean in dogs? ›
In dogs with sepsis, PCT concentrations at hospital admissions are predictive of organ dysfunction and septic shock. Serial procalcitonin monitoring may offer valuable prognostic information in canine sepsis, wherein early decreases in PCT concentrations are associated with survival.What does elevated PCT mean in a dog? ›
A high level of plasma proteins in the blood is caused by hyperproteinemia, which can be a sign of many illnesses, both mild and serious, such as infection, dehydration, and lymphocytic leukemia.What is a high platelet count in dogs? ›
If your dog has thrombocytosis it means he has too many platelets circulating in his bloodstream. This can lead to altered blood flow and even clot formation within the bloodstream where it should not be.What mimics Cushing's disease in dogs? ›
Some of these symptoms, such as drinking and urinating excessively, mimic other diseases such as diabetes, kidney disease, urinary tract infections, etc.