Urinary and Endocrine SBAs Flashcards
(78 cards)
A 9-year-old neutered male Cairn Terrier weighing 15kg is diagnosed with pituitary-dependent hyperadrenocorticism (PDH). He has no other concurrent health issues.
Lead-in: According to the provided information, what is the recommended first-line treatment for this dog?
Options:
a) Surgical removal of the adrenal glands.
b) Administration of metyrapone.
c) Administration of trilostane.
d) Radiation therapy to the pituitary gland.
e) Dietary management with a low-protein diet.
Answer: c) Administration of trilostane.
Following the initiation of trilostane therapy for canine hyperadrenocorticism, a follow-up appointment is typically scheduled to assess the patient’s response.
Lead-in: According to the provided treatment and monitoring approach, when is the first ACTH stimulation test recommended after starting trilostane?
Options:
a) 3 days
b) 7 days
c) 10 days
d) 28 days
e) 12 weeks
Answer: c) 10 days
Explanation: The document “1 - Adrenal disease SDL.pdf” states that monitoring includes an ACTH stimulation test on day 10.
A rare type of functional adrenocortical tumour can lead to clinical signs related to hypokalaemia, such as muscle weakness and, in cats, ventroflexion of the neck.
Lead-in: Which hormone is primarily associated with this type of tumour?
Options:
a) Cortisol
b) ACTH
c) Aldosterone
d) Androstenedione
e) 17-hydroxyprogesterone (17-OP)
Answer: c) Aldosterone
Explanation: The document mentions that these mineralocorticoid-like tumours are associated with aldosterone.
A dog presents with clinical signs that could be confused with hyperadrenocorticism, including polyuria, polydipsia, and panting. An adrenal mass is noted on imaging, and the dog has persistent hyperglycaemia.
Lead-in: Which of the following adrenal tumours should be considered as a differential in this case?
Options:
a) Adrenal adenoma
b) Adrenal carcinoma
c) Phaechromocytoma
d) Cortisol-producing adrenal tumour
e) Mineralocorticoid-producing adrenal tumour
Answer: c) Phaechromocytoma
Explanation: The document highlights that phaechromocytoma can mimic hyperadrenocorticism and presents with similar signs, along with an adrenal mass and hyperglycaemia.
A 7-year-old spayed female Poodle has been receiving trilostane for pituitary-dependent hyperadrenocorticism for the past six months. While her initial clinical signs improved, they have recently started to recur. Her owner reports increased drinking and urination. An ACTH stimulation test reveals an inadequate suppression of cortisol levels.
Lead-in: Based on the information given above, the current treatment with trilostane is not optimally controlling the hyperadrenocorticism. Wwhat alternative medical treatment might be considered if trilostane is not sufficiently effective or tolerated?
Options:
a) Increasing the dose of trilostane significantly
b) Switching to a once-daily trilostane administration
c) Initiating treatment with ketoconazole
d) Initiating treatment with mitotane
e) Adding prednisolone to the treatment regimen
Answer: d) Initiating treatment with mitotane
Explanation: Mitotane is another medication that can be used to treat pituitary-dependent hyperadrenocorticism, often considered if trilostane is ineffective or not tolerated.
A 6-year-old male Domestic Shorthair cat presents with progressive muscle weakness and episodic ventroflexion of the neck. Bloodwork reveals marked hypokalaemia. An ACTH stimulation test does not show elevated cortisol levels. Further investigation reveals an adrenal mass.
Lead-in: Based on the information given above, you suspect a functional adrenocortical tumour that is not primarily producing cortisol. Which specific medication might be used to manage the clinical signs associated with this type of tumour in cats?
Options:
a) Trilostane
b) Metyrapone
c) Spironolactone
d) Fludrocortisone
e) Prednisolone
Answer: c) Spironolactone
A 10-year-old neutered male Labrador Retriever presents with a two-week history of polyuria, polydipsia, and polyphagia. On physical examination, he has mild cataracts. Which of the following is the most likely underlying pathophysiology for these clinical signs?
a) Decreased insulin production leading to increased cellular glucose uptake.
b) Increased glucagon secretion resulting in hyperglycaemia.
c) Insulin resistance causing impaired glucose utilisation and subsequent hyperglycaemia.
d) Increased renal tubular reabsorption of glucose.
e) Impaired glycogenolysis in the liver.
Answer: c) Insulin resistance causing impaired glucose utilisation and subsequent hyperglycaemia.
Explanation: While absolute insulin deficiency is common in dogs, insulin resistance can also play a role. The clinical signs are consistent with hyperglycaemia exceeding the renal threshold for glucose reabsorption, leading to osmotic diuresis. Cataracts in dogs are a common complication of diabetes mellitus.
A newly diagnosed diabetic dog is started on twice-daily insulin injections. The owner is concerned about potential complications. Which of the following is the most common complication associated with insulin therapy in dogs?
a) Diabetic ketoacidosis
b) Hypoglycaemia
c) Hyperglycaemia
d) Urinary tract infection
e) Pancreatitis
Answer: b) Hypoglycaemia
Explanation: Hypoglycaemia is a significant risk with insulin therapy if the dose is too high, the dog misses a meal, or exercises excessively.
Which of the following insulin preparations is typically recommended for initial stabilisation of uncomplicated diabetes mellitus in dogs?
a) Insulin glargine
b) Protamine zinc insulin (PZI)
c) Neutral protamine Hagedorn (NPH) insulin
d) Insulin detemir
e) Rapid-acting insulin
Answer: c) Neutral protamine Hagedorn (NPH) insulin
Explanation: NPH insulin (Caninsulin) is a commonly used intermediate-acting insulin for dogs, typically administered twice daily.
Which of the following dietary recommendations is generally most appropriate for a dog with diabetes mellitus?
a) High carbohydrate, low fibre diet fed ad libitum.
b) Low carbohydrate, high protein diet fed once daily.
c) Consistent diet with consistent meal times, often high in fibre.
d) Palatable diet with variable composition to encourage eating.
e) Supplementation with high levels of simple sugars to maintain energy.
Answer: c) Consistent diet with consistent meal times, often high in fibre.
Explanation: Consistency in diet and feeding schedule is crucial for managing blood glucose levels in diabetic dogs. High-fibre diets can help slow glucose absorption.
Which of the following monitoring methods is considered the gold standard for assessing glycaemic control in diabetic dogs at home?
a) Urine glucose monitoring
b) Serial blood glucose measurements using a glucometer
c) Clinical signs reported by the owner
d) Fructosamine levels measured every 3 months
e) Glycated haemoglobin (HbA1c) levels
Answer: b) Serial blood glucose measurements using a glucometer
Explanation: While other methods are used, serial blood glucose measurements at home provide the most detailed information about daily glucose fluctuations.
A diabetic cat presents with plantigrade stance and hindlimb weakness. Which of the following is the most likely underlying cause?
a) Hypoglycaemia
b) Hyperglycaemia
c) Diabetic ketoacidosis
d) Diabetic neuropathy
e) Insulinoma
Answer: d) Diabetic neuropathy
Explanation: Diabetic neuropathy is a common complication in cats, characterised by nerve damage that can lead to muscle weakness and an abnormal stance.
What is the typical duration of action for protamine zinc insulin (PZI) in cats?
a) 4-6 hours
b) 8-12 hours
c) 12-18 hours
d) 18-24 hours
e) >24 hours
Answer: e) >24 hours
Explanation: PZI is a long-acting insulin often used in cats, with a duration of action that can exceed 24 hours in some individuals.
Scenario: A 5-year-old neutered male Miniature Poodle presents with a history of recent onset muscle tremors, facial rubbing, and seizures. On physical examination, his temperature is 38.2°C, heart rate is 90 bpm, and he exhibits marked hyperreflexia. Initial bloodwork reveals a total calcium concentration of 1.5 mmol/L (reference range: 2.2-3.0 mmol/L).
Lead-in: Which of the following is the most likely underlying cause for this dog’s hypocalcaemia?
Options:
a) Primary hyperparathyroidism
b) Vitamin D toxicity
c) Hypoalbuminaemia
d) Primary hypoparathyroidism
e) Chronic kidney disease
Answer: d) Primary hypoparathyroidism
Explanation: The clinical signs of muscle tremors, facial rubbing, and seizures, along with a very low total calcium concentration, are highly suggestive of primary hypoparathyroidism. This condition leads to decreased production of parathyroid hormone (PTH), which is essential for calcium regulation. While hypoalbuminaemia can lower total calcium, it typically does not cause such severe clinical signs or a calcium level this low. Primary hyperparathyroidism causes hypercalcaemia. Vitamin D toxicity also leads to hypercalcaemia. Chronic kidney disease can cause hypocalcaemia, but it is less likely to present with acute, severe neurological signs and such a low calcium level as the primary finding.
Scenario: A 6-year-old male neutered Labrador Retriever underwent a total thyroidectomy for thyroid carcinoma. Two days post-operatively, the dog is showing signs of restlessness, muscle twitching, and panting. His temperature is 38.5°C, and his heart rate is 110 bpm.
Lead-in: What is the most likely electrolyte abnormality causing these clinical signs?
Options:
a) Hyperkalaemia
b) Hyponatraemia
c) Hypocalcaemia
d) Hyperphosphataemia
e) Hypomagnesaemia
Answer: c) Hypocalcaemia
Explanation: Total thyroidectomy can lead to inadvertent removal or damage to the parathyroid glands, resulting in hypoparathyroidism and subsequent hypocalcaemia. The clinical signs of restlessness, muscle twitching, and panting are consistent with hypocalcaemia
Scenario: A 4-year-old spayed female Cavalier King Charles Spaniel presents with polyuria, polydipsia, and lethargy. Bloodwork reveals a total calcium concentration of 3.5 mmol/L (reference range: 2.2-2.8 mmol/L) and a low phosphorus level. Further investigation reveals an elevated parathyroid hormone-related peptide (PTH-rp).
Lead-in: What is the most likely underlying cause of this dog’s hypercalcaemia?
Options:
a) Primary hyperparathyroidism
b) Vitamin D toxicity
c) Humoral hypercalcaemia of malignancy
d) Granulomatous disease
e) Chronic kidney disease
Answer: c) Humoral hypercalcaemia of malignancy
Explanation: The presence of hypercalcaemia, low phosphorus, and elevated PTH-rp strongly suggests humoral hypercalcaemia of malignancy. PTH-rp is a substance secreted by certain tumours that mimics the effects of PTH, leading to increased calcium levels. Primary hyperparathyroidism would typically present with elevated PTH, not PTH-rp. Vitamin D toxicity causes increased calcium and phosphorus. Granulomatous diseases can cause hypercalcaemia due to increased production of calcitriol, but PTH-rp would not be elevated. Chronic kidney disease typically leads to hypocalcaemia.
Scenario: A 7-year-old male neutered Golden Retriever presents with a history of progressive muscle weakness and exercise intolerance. On physical examination, he has a stiff gait and palpable lymphadenomegaly. Bloodwork reveals a total calcium concentration of 3.3 mmol/L (reference range: 2.2-2.8 mmol/L).
Lead-in: Based on these findings, which diagnostic test would be most informative in determining the cause of the hypercalcaemia?
Options:
a) Measurement of ionised calcium
b) Parathyroid hormone (PTH) level
c) Lymph node cytology
d) Abdominal radiographs
e) Urine analysis
Answer: c) Lymph node cytology
Explanation: The combination of hypercalcaemia, muscle weakness, exercise intolerance, and lymphadenomegaly raises suspicion for lymphoma, which is a common cause of hypercalcaemia in dogs (page 38). Lymph node cytology would be the most direct way to investigate the lymphadenomegaly and potentially diagnose lymphoma. While ionised calcium might provide a more accurate calcium measurement, it won’t identify the underlying cause. PTH level would help rule out primary hyperparathyroidism but is less likely in this scenario. Abdominal radiographs might reveal enlarged lymph nodes but cytology is more specific. Urine analysis is unlikely to provide a definitive diagnosis for hypercalcaemia in this context.
Scenario: A 10-year-old West Highland White Terrier presents with a history of progressive lethargy, inappetence, and increased thirst and urination over the past six months. On physical examination, the dog has poor body condition, pale mucous membranes, and small, firm kidneys on palpation.
Lead-in: Based on the history and clinical findings, which of the following is the most likely diagnosis?
Options:
a) Acute kidney injury due to ethylene glycol toxicity
b) Chronic kidney disease, likely stage 3 or 4
c) Urinary tract infection with secondary pyelonephritis
d) Polycystic kidney disease
e) Amyloidosis causing nephrotic syndrome
Answer: b) Chronic kidney disease, likely stage 3 or 4
Explanation: The history of progressive signs over months, poor body condition, pale mucous membranes (suggesting non-regenerative anaemia), and small, firm kidneys are highly suggestive of chronic kidney disease (CKD). Stages 3 and 4 of CKD are characterised by moderate to severe azotaemia and clinical signs consistent with uraemia. Acute kidney injury typically presents with a sudden onset of signs. While ethylene glycol toxicity can cause acute kidney injury, the chronic history makes this less likely. Urinary tract infection and pyelonephritis can cause kidney damage, but the small, firm kidneys are more indicative of chronic disease. Polycystic kidney disease can cause enlarged, irregular kidneys. Amyloidosis can lead to nephrotic syndrome, which includes proteinuria and potentially oedema, and while it can be chronic, the small kidney size is less typical.
Scenario: A 6-year-old Persian cat is presented for a routine pre-breeding health check. The cat is clinically normal. As part of the screening, an abdominal ultrasound is performed, revealing multiple small, fluid-filled cysts in both kidneys.
Lead-in: What is the most likely underlying condition in this cat?
Options:
a) Chronic interstitial nephritis
b) Renal lymphoma
c) Polycystic kidney disease
d) Feline infectious peritonitis (FIP)
e) Pyelonephritis
Answer: c) Polycystic kidney disease
Explanation: The presence of multiple fluid-filled cysts in both kidneys of a Persian cat is highly suggestive of polycystic kidney disease (PKD), an autosomal dominant hereditary condition common in this breed. Screening is recommended in Persian cats before breeding due to the prevalence of this disease. Chronic interstitial nephritis is a common cause of CKD but doesn’t typically present with multiple distinct cysts on ultrasound. Renal lymphoma usually causes enlarged, irregular kidneys. FIP can cause various clinical signs and organ involvement, but the specific finding of multiple renal cysts is less typical. Pyelonephritis is a bacterial infection of the kidneys and may cause pelvic dilation on ultrasound but not usually multiple cysts throughout the parenchyma
Scenario: A 7-year-old Labrador Retriever is diagnosed with stage 2 chronic kidney disease based on stable creatinine and SDMA levels. The urine protein:creatinine ratio (UPCR) is 0.6.
Lead-in: Which of the following treatment options is most appropriate to manage the proteinuria in this dog?
Options:
a) Administer a calcium channel blocker such as amlodipine
b) Initiate treatment with an angiotensin receptor blocker (ARB) such as telmisartan
c) Prescribe a low-protein diet
d) Administer enteric phosphate binders such as aluminium hydroxide
e) Start treatment with a third-generation cephalosporin
Answer: b) Initiate treatment with an angiotensin receptor blocker (ARB) such as telmisartan
Explanation: For dogs with CKD and a UPCR > 0.5, treatment with a RAAS inhibitor (ACE inhibitor or ARB) and a clinical renal diet is recommended to manage proteinuria. Telmisartan is an angiotensin receptor blocker (ARB) and is a suitable choice. Amlodipine is used to treat hypertension. While a renal diet with restricted protein is beneficial for CKD, it is not the primary treatment for significant proteinuria. Phosphate binders are used to manage hyperphosphataemia. Antibiotics are indicated for bacterial infections.
Scenario: A 5-year-old Maine Coon cat with known stage 3 chronic kidney disease presents with a sudden onset of blindness. On examination, the cat is hypertensive with a systolic blood pressure of 190 mmHg.
Lead-in: What is the most appropriate first-line treatment to address the hypertension in this cat?
Options:
a) Intravenous administration of furosemide
b) Oral administration of benazepril
c) Oral administration of amlodipine
d) Subcutaneous administration of erythropoietin
e) Dietary management with a sodium-restricted diet
Answer: c) Oral administration of amlodipine
Explanation: In cats with hypertension, especially with evidence of end-organ damage such as acute blindness due to retinal detachment, a calcium channel blocker like amlodipine is the first-line treatment. The aim is to rapidly reduce blood pressure to below 150 mmHg, which is crucial in cases with severe ocular or CNS signs. Furosemide is a loop diuretic and not the primary choice for managing hypertension. Benazepril is an ACE inhibitor, which is less effective than amlodipine for lowering blood pressure in cats unless proteinuria is also present. Erythropoietin is used to treat non-regenerative anaemia associated with CKD. While sodium restriction is part of the dietary management of CKD, it is not sufficient to treat severe hypertension acutely.
Scenario: A 9-year-old domestic shorthair cat with stage 4 chronic kidney disease is anorexic and vomiting. Blood tests reveal azotaemia and hyperkalaemia (potassium = 6.8 mmol/L).
Lead-in: Which of the following is the most appropriate immediate treatment to address the hyperkalaemia?
Options:
a) Intravenous fluids with potassium supplementation
b) Oral administration of aluminium hydroxide
c) Intravenous administration of calcium gluconate
d) Subcutaneous administration of erythropoietin
e) Oral administration of mirtazapine
Answer: c) Intravenous administration of calcium gluconate
Explanation: Hyperkalaemia can be life-threatening, especially in patients with acute or chronic kidney disease. Calcium gluconate does not lower potassium levels but protects the heart from the effects of hyperkalaemia by increasing the threshold potential of cardiac myocytes. Intravenous fluids are important for dehydration but should be potassium-free in this case. Aluminium hydroxide is a phosphate binder. Erythropoietin treats anaemia. Mirtazapine is an appetite stimulant. While other treatments like glucose and insulin or bicarbonate can help lower potassium, calcium gluconate provides immediate cardioprotection.
Scenario: A 4-year-old male neutered domestic shorthair cat presents with a history of anorexia, lethargy, and vomiting for 24 hours. On physical examination, the cat is dehydrated and has a painful, enlarged bladder on palpation.
Lead-in: What is the most likely underlying cause of this cat’s condition?
Options:
a) Acute kidney injury due to lily toxicity
b) Urethral obstruction leading to post-renal azotaemia
c) Pyelonephritis
d) Chronic kidney disease exacerbation
e) Ureterolithiasis
Answer: b) Urethral obstruction leading to post-renal azotaemia
Explanation: The acute onset of anorexia, lethargy, and vomiting, along with dehydration and a painful, enlarged bladder in a male cat, strongly suggests a urethral obstruction. This leads to a build-up of toxins and back pressure on the kidneys, resulting in post-renal azotaemia. Lily toxicity causes intrinsic acute kidney injury, but bladder distension is not a typical finding. Pyelonephritis is a bacterial infection and may cause renal pain, but a distended bladder is less likely. Chronic kidney disease exacerbations usually have a longer history. Ureterolithiasis (stones in the ureters) can cause post-renal azotaemia but typically doesn’t result in a palpably enlarged bladder unless both ureters are obstructed, which is less common than urethral obstruction in male cats.
Scenario: A 2-year-old Basenji presents with a history of increased thirst and urination since puppyhood. Blood tests reveal normal serum creatinine and urea, but urinalysis shows glucosuria despite normoglycaemia.
Lead-in: What is the most likely underlying condition in this breed with these findings?
Options:
a) Diabetes mellitus
b) Chronic kidney disease, stage 1
c) Fanconi’s syndrome
d) Primary hyperparathyroidism
e) Central diabetes insipidus
Answer: c) Fanconi’s syndrome
Explanation: The combination of increased thirst and urination, normal serum creatinine and urea, and glucosuria despite normal blood glucose levels in a young Basenji is highly suggestive of Fanconi’s syndrome. This is a disease of the proximal renal tubules where there is reduced resorption of glucose, electrolytes, and other solutes, leading to their loss in the urine. It can be hereditary in Basenjis. Diabetes mellitus would typically present with hyperglycaemia. Stage 1 CKD might not show glucosuria. Primary hyperparathyroidism can cause increased thirst and urination and potentially kidney damage, but glucosuria is not a typical finding. Central diabetes insipidus causes polyuria and polydipsia but not glucosuria.