Urinary and Endocrine SBAs Flashcards
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.
Scenario: A 50kg Great Dane presents with a one-week history of lethargy, inappetence, and vomiting. Blood tests reveal a markedly elevated creatinine of 8.0 mg/dL and a blood urea nitrogen (BUN) of 90 mg/dL. Urine specific gravity is 1.010.
Lead-in: Based on these findings, the dog is most likely suffering from:
Options:
a) Pre-renal azotaemia
b) Post-renal azotaemia
c) Intrinsic acute kidney injury
d) Chronic kidney disease, stage 2
e) Decompensated chronic kidney disease
Answer: c) Intrinsic acute kidney injury
Explanation: The acute onset of severe azotaemia (high creatinine and BUN) with inappropriately dilute urine (USG 1.010) indicates intrinsic damage to the kidneys, consistent with acute kidney injury (AKI). Pre-renal azotaemia is usually due to dehydration and would typically resolve with fluid therapy, and urine would be concentrated if the kidneys were functioning normally. Post-renal azotaemia is due to urinary obstruction, which is not suggested by the urine specific gravity alone. Stage 2 chronic kidney disease would typically have lower creatinine levels. Decompensated chronic kidney disease also presents with azotaemia but usually with a longer history and often smaller kidneys.
Scenario: A cat is diagnosed with pyelonephritis. Urine culture reveals a sensitive E. coli infection. The cat also has stage 2 chronic kidney disease.
Lead-in: Which of the following antibiotic choices would be most appropriate for this cat, considering its CKD status and the need to choose a renally excreted drug?
Options:
a) PO Enrofloxacin
b) IV Gentamicin
c) PO Amoxicillin-clavulanate
d) S/C Cefovecin
e) S/C Trimethoprim-sulfamethoxazole
Answer: c) Amoxicillin-clavulanate
Explanation: When treating urinary tract infections or pyelonephritis in patients with chronic kidney disease, it is important to choose renally excreted drugs. Amoxicillin-clavulanate is a suitable choice for E. coli and is primarily excreted by the kidneys. Enrofloxacin should be avoided in cats due to potential nephrotoxicity. Gentamicin is an aminoglycoside antibiotic that is nephrotoxic and should be avoided in CKD patients. Cefovecin is a third-generation cephalosporin, and while it can be used, amoxicillin-clavulanate is often a good first-line choice for E. coli. Trimethoprim-sulfamethoxazole can have adverse effects in CKD patients.
Scenario: A 12-year-old cat with known chronic kidney disease presents with anaemia (haematocrit 20%).
Lead-in: What is the underlying pathophysiology most likely contributing to this anaemia in a patient with CKD?
Options:
a) Increased red blood cell destruction due to uraemic toxins
b) Iron deficiency due to poor appetite
c) Reduced production of erythropoietin by the kidneys
d) Gastrointestinal blood loss from uraemic ulcers
e) Bone marrow suppression due to hyperparathyroidism
Answer: c) Reduced production of erythropoietin by the kidneys
Explanation: Chronic kidney disease leads to a decreased production of erythropoietin (EPO) by the kidneys. EPO is a hormone that stimulates red blood cell production in the bone marrow. Reduced EPO levels result in a non-regenerative anaemia, which is a common complication of CKD. While uraemic toxins can have various effects, reduced EPO production is the primary cause of anaemia in CKD. Iron deficiency can occur due to poor appetite, but it’s not the main reason. Gastrointestinal blood loss from uraemic ulcers can contribute but is not the primary mechanism. Hyperparathyroidism in CKD affects calcium and phosphorus homeostasis and bone remodelling, not directly red blood cell production.
Scenario: A 6-year-old female neutered Border Collie presents with a history of progressive weight loss and lethargy over the past three months. Blood tests reveal azotaemia and a urine protein:creatinine ratio (UPCR) of 4.0.
Lead-in: Based on the high UPCR, which of the following is the most likely underlying cause of the chronic kidney disease in this dog?
Options:
a) Polycystic kidney disease
b) Glomerular disease
c) Pyelonephritis
d) Nephrotoxic insult
e) Ureterolithiasis
Answer: b) Glomerular disease
Explanation: A UPCR > 3.5 in dogs with chronic kidney disease suggests a primary glomerular disease as the likely underlying cause. Glomerular diseases cause increased leakage of protein into the urine. Polycystic kidney disease is characterised by cysts. Pyelonephritis is an infection. Nephrotoxic insults can cause kidney damage, but a persistently high UPCR is more suggestive of glomerular disease. Ureterolithiasis causes post-renal azotaemia.
Scenario: A 4-year-old cat is diagnosed with acute kidney injury. Despite appropriate intravenous fluid therapy, the cat remains oliguric (urine output < 1 ml/kg/hour).
Lead-in: Which of the following medications might be considered to try and increase urine output in this cat, although evidence for improved outcomes in AKI is limited?
Options:
a) Enalapril
b) Furosemide
c) Mannitol
d) Benazepril
e) Spironolactone
Answer: b) Furosemide
Explanation: Loop diuretics like furosemide are sometimes used in oliguric acute kidney injury to try and promote urine output and prevent fluid overload, although evidence for improved outcomes is not strong. However, furosemide should be used cautiously in poorly hydrated patients as it can be nephrotoxic. Enalapril and benazepril are ACE inhibitors, which are generally avoided in acute kidney injury as they can reduce afferent renal blood flow. Mannitol can be used for osmotic diuresis but may also cause AKI itself. Spironolactone is an aldosterone antagonist and a potassium-sparing diuretic, not typically used in the acute management of oliguria in AKI.
Scenario: A dog presents with acute kidney injury secondary to suspected leptospirosis.
Lead-in: Which antibiotic would be the most appropriate treatment?
Options:
a) Amoxicillin IV, followed by PO administration.
b) Oxytetracycline IM, followed by PO administration.
c) Enrofloxacin orally
d) Doxycycline orally
e) Gentamicin IV
d) Doxycycline orally
Scenario: A dog with acute kidney injury is not responding to conventional medical management. The creatinine levels remain high (IRIS AKI Grade IV), and the dog is oliguric and severely unwell. The owner is considering further treatment options.
Lead-in: Which of the following advanced treatment options might be discussed with the owner for a dog with severe, refractory acute kidney injury?
Options:
a) Peritoneal dialysis
b) Increased doses of loop diuretics
c) Administration of corticosteroids
d) Surgical removal of both kidneys
e) Oral activated charcoal
Answer: a) Peritoneal dialysis
Explanation: For severe acute kidney injury (IRIS AKI Grade IV or V) that is not responding to conventional management, renal replacement therapy (RRT) such as peritoneal dialysis or haemodialysis may be considered. These therapies help to remove waste products and excess fluid from the body when the kidneys are failing. Increasing doses of loop diuretics in anuric or severely oliguric patients is unlikely to be effective and can be harmful. Corticosteroids are not a standard treatment for most causes of AKI. Surgical removal of both kidneys would be a last resort in cases of severe renal neoplasia or untreatable conditions, not typically for AKI. Activated charcoal is used for certain types of toxin ingestion early in the course of AKI.
Scenario: A 5-year-old Burmese cat presents with a two-day history of anorexia, lethargy, and vomiting. On physical examination, the cat is moderately dehydrated, and the kidneys are palpably enlarged and painful. Initial bloodwork reveals a serum creatinine of 247 µmol/L and a urine specific gravity of 1.015.
Lead-in: Based on these findings and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this cat?
Options:
a) Grade I
b) Grade II
c) Grade III
d) Grade IV
e) Grade V
Answer: c) Grade III
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine between 141 and 442 µmol/L in cats with clinical signs consistent with AKI (anorexia, lethargy, vomiting, painful kidneys) and a urine specific gravity below 1.030 typically falls into Grade III. Grade I would have creatinine <140 µmol/L, Grade II between 141-221 µmol/L, Grade IV between 443-884 µmol/L, and Grade V >884 µmol/L.
Scenario: A 9-year-old Labrador Retriever presents for routine bloodwork as part of a senior health screen. The dog is clinically normal. The bloodwork reveals a serum creatinine of 133 µmol/L and an SDMA of 20 µg/dL. A urinalysis shows a urine specific gravity of 1.022.
Lead-in: According to the 2023 IRIS CKD staging guidelines, what is the most appropriate IRIS stage for this dog?
Options:
a) Stage 1
b) Stage 2
c) Stage 3
d) Stage 4
e) Cannot be determined based on this information alone.
Answer: a) Stage 1
Explanation: According to the 2023 IRIS CKD staging guidelines, a dog with a serum creatinine <140 µmol/L and an SDMA between 18-25 µg/dL is classified as Stage 1 CKD. The urine specific gravity of 1.022 is below the ideal for ruling out renal disease entirely but is not a primary criterion for staging in the absence of other findings. Since the SDMA is above 18 µg/dL, it supports a diagnosis of Stage 1 even with a creatinine in the normal range.
Scenario: A 13-year-old domestic shorthair cat with a history of weight loss and increased thirst presents for investigation of possible chronic kidney disease. Bloodwork reveals a serum creatinine of 283 µmol/L and an SDMA of 45 µg/dL. The cat is normotensive and the urine protein:creatinine ratio (UPCR) is 0.4.
Lead-in: Based on the 2023 IRIS CKD staging guidelines, what is the IRIS stage for this cat?
Options:
a) Stage 1
b) Stage 2
c) Stage 3
d) Stage 4
e) Cannot be determined without further information.
Answer: c) Stage 3
Explanation: According to the 2023 IRIS CKD staging guidelines, a cat with a serum creatinine between 246 and 442 µmol/L or an SDMA between 36 and 75 µg/dL is classified as Stage 3 CKD. The UPCR of 0.4 places this cat in the non-proteinuric to borderline proteinuric substage, and the blood pressure is within the normal range.
Scenario: A 7-year-old Boxer presents with a sudden onset of haematuria and oliguria following ingestion of an unknown substance. Bloodwork reveals a serum creatinine of 575 µmol/L and a urine specific gravity of 1.008.
Lead-in: Based on these findings and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this dog?
Options:
a) Grade I
b) Grade II
c) Grade III
d) Grade IV
e) Grade V
Answer: d) Grade IV
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine between 443 and 884 µmol/L in dogs with clinical signs of AKI (haematuria, oliguria) and a poorly concentrated urine specific gravity (1.008) falls into Grade IV.
Scenario: A 15-year-old mixed breed dog with known IRIS stage 4 chronic kidney disease presents with worsening lethargy and inappetence. Bloodwork reveals a serum creatinine of 839 µmol/L and an SDMA of 85 µg/dL.
Lead-in: According to the 2023 IRIS CKD staging guidelines, what is the current IRIS stage for this dog?
Options:
a) Stage 2
b) Stage 3
c) Stage 4
d) Stage 5
e) The stage remains the same (Stage 4).
Answer: c) Stage 4
Explanation: According to the 2023 IRIS CKD staging guidelines, a dog with a serum creatinine >442 µmol/L or an SDMA >75 µg/dL is classified as Stage 4 CKD. The presented values are consistent with this stage. There is no Stage 5 in the IRIS CKD staging.
Scenario: A 2-year-old cat is found collapsed and unresponsive. Initial bloodwork reveals a serum creatinine of 1326 µmol/L. Urine output cannot be assessed at this time.
Lead-in: Based on the serum creatinine alone and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this cat?
Options:
a) Grade II
b) Grade III
c) Grade IV
d) Grade V
e) Cannot be determined without urine specific gravity.
Answer: d) Grade V
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine >884 µmol/L in cats is classified as Grade V, regardless of urine specific gravity.
Scenario: A 10-year-old Beagle with a history of well-managed stage 2 chronic kidney disease presents for a recheck. Over the past month, the owner has noticed increased thirst and urination. Bloodwork now reveals a serum creatinine of 194 µmol/L (previously 159 µmol/L) and an SDMA of 30 µg/dL (previously 22 µg/dL).
Lead-in: According to the 2023 IRIS CKD staging guidelines, what is the current IRIS stage for this dog?
Options:
a) Stage 1
b) Stage 2
c) Stage 3
d) Stage 4
e) The stage remains the same (Stage 2).
Answer: c) Stage 3
Explanation: According to the 2023 IRIS CKD staging guidelines, a dog with a serum creatinine between 140 and 246 µmol/L or an SDMA between 26 and 50 µg/dL is classified as Stage 3 CKD. The current values for both creatinine and SDMA now fall into Stage 3, indicating progression of the disease.
Scenario: A 4-year-old Maine Coon cat presents with a history of lethargy and decreased appetite for three days. On physical examination, the cat is dehydrated. Bloodwork reveals a serum creatinine of 177 µmol/L and a urine specific gravity of 1.045.
Lead-in: Based on these findings and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this cat?
Options:
a) Grade I
b) Grade II
c) Grade III
d) Grade IV
e) This is likely pre-renal azotaemia, not true AKI.
Answer: b) Grade II
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine between 141 and 221 µmol/L in cats with clinical signs of AKI (lethargy, decreased appetite, dehydration) and a urine specific gravity >1.030 falls into Grade II. While pre-renal azotaemia can cause elevated creatinine, the presence of clinical signs and a creatinine in this range with a concentrated urine supports Grade II AKI.
Scenario: A 14-year-old Yorkshire Terrier with known IRIS stage 3 chronic kidney disease presents for a routine check. Bloodwork reveals a stable serum creatinine of 309 µmol/L and an SDMA of 55 µg/dL. The urine protein:creatinine ratio (UPCR) has increased from 0.2 to 0.6.
Lead-in: According to the 2023 IRIS CKD staging guidelines, what is the current classification for this dog, specifically regarding proteinuria?
Options:
a) Non-proteinuric
b) Borderline proteinuric
c) Proteinuric
d) Severely proteinuric
e) The proteinuria status remains unchanged.
Answer: c) Proteinuric
Explanation: According to the 2023 IRIS CKD substaging based on proteinuria, a UPCR between 0.5 and 1.0 in dogs is classified as proteinuric. The previous UPCR of 0.2 was non-proteinuric (<0.2 in cats, <0.3 in dogs). Therefore, the dog has progressed to the proteinuric substage.
Scenario: A 6-year-old domestic shorthair cat presents with a history of acute onset of vomiting and lethargy. Bloodwork shows a serum creatinine of 424 µmol/L and a urine specific gravity of 1.028.
Lead-in: Based on these findings and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this cat?
Options:
a) Grade I
b) Grade II
c) Grade III
d) Grade IV
e) Grade V
Answer: c) Grade III
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine between 221 and 442 µmol/L in cats with clinical signs of AKI (vomiting, lethargy) and a urine specific gravity between 1.026 and 1.030 falls into Grade III.
Scenario: An 8-year-old Golden Retriever presents with a history of progressive polyuria and polydipsia. Bloodwork reveals a serum creatinine of 221 µmol/L and an SDMA of 38 µg/dL. Urinalysis shows a urine specific gravity of 1.018.
Lead-in: According to the 2023 IRIS CKD staging guidelines, what is the IRIS stage for this dog?
Options:
a) Stage 1
b) Stage 2
c) Stage 3
d) Stage 4
e) Cannot be determined without further information.
Answer: c) Stage 3
Explanation: According to the 2023 IRIS CKD staging guidelines, a dog with a serum creatinine between 140 and 246 µmol/L or an SDMA between 26 and 50 µg/dL is classified as Stage 3 CKD. The urine specific gravity of 1.018 supports the presence of kidney dysfunction.
Scenario: A 3-year-old cat is presented after ingesting antifreeze (ethylene glycol). Initial bloodwork reveals a serum creatinine of 636 µmol/L.
Lead-in: Based on the serum creatinine alone and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this cat?
Options:
a) Grade II
b) Grade III
c) Grade IV
d) Grade V
e) Cannot be determined without urine specific gravity.
Answer: c) Grade IV
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine between 443 and 884 µmol/L in cats is classified as Grade IV, regardless of urine specific gravity.
Scenario: A 16-year-old cat with known IRIS stage 4 chronic kidney disease presents for a recheck. The owner reports that the cat is doing well and bloodwork reveals a stable serum creatinine of 530 µmol/L and an SDMA of 78 µg/dL. The systolic blood pressure is consistently above 170 mmHg despite treatment.
Lead-in: According to the 2023 IRIS CKD staging guidelines, what is the current classification for this cat, specifically regarding hypertension?
Options:
a) Normotensive
b) Prehypertensive
c) Stage 1 Hypertension
d) Stage 2 Hypertension
e) Stage 3 Hypertension
Answer: e) Stage 3 Hypertension
Explanation: According to the 2023 IRIS CKD substaging based on blood pressure, a systolic blood pressure consistently >160 mmHg is classified as Stage 3 Hypertension.
Scenario: A 7-year-old mixed breed dog presents with a history of vomiting and lethargy. Bloodwork reveals a serum creatinine of 265 µmol/L and a urine specific gravity of 1.012.
Lead-in: Based on these findings and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this dog?
Options:
a) Grade I
b) Grade II
c) Grade III
d) Grade IV
e) This is likely chronic kidney disease.
Answer: c) Grade III
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine between 221 and 442 µmol/L in dogs with clinical signs of AKI (vomiting, lethargy) and a urine specific gravity <1.020 falls into Grade III.
Scenario: A 5-year-old cat with no prior history of kidney disease presents with sudden onset of anuria. Bloodwork reveals a serum creatinine of 1061 µmol/L.
Lead-in: Based on the serum creatinine alone and the IRIS AKI grading, what is the most likely IRIS grade of acute kidney injury in this cat?
Options:
a) Grade II
b) Grade III
c) Grade IV
d) Grade V
e) Cannot be determined without urine specific gravity.
Answer: d) Grade V
Explanation: According to the IRIS AKI grading guidelines, a serum creatinine >884 µmol/L in cats is classified as Grade V, regardless of urine specific gravity or urine output. The anuria further supports severe kidney dysfunction.
Scenario: A 3-year-old female rabbit presents with a history of anorexia, lethargy, and hunched posture for 24 hours. On physical examination, the rabbit is dehydrated, and palpation of the abdomen reveals enlarged, firm kidneys. Bloodwork shows azotaemia.
Lead-in: Which of the following is the most likely differential diagnosis for the enlarged, firm kidneys in this rabbit?
Options:
a) Uterine adenocarcinoma
b) Encephalitozoon cuniculi infection
c) Calcium oxalate urolithiasis
d) Polycystic kidney disease
e) Hepatic lipidosis
Answer: d) Polycystic kidney disease
Explanation: Polycystic kidney disease is a known condition in rabbits, particularly certain breeds, and can lead to enlarged, firm kidneys and subsequent renal failure. Uterine adenocarcinoma is more likely to cause a palpable abdominal mass in the caudal abdomen. Encephalitozoon cuniculi can cause renal disease, but kidney enlargement is not a consistent finding. Calcium oxalate urolithiasis typically affects the ureters or bladder. Hepatic lipidosis is a liver condition and would not cause enlarged kidneys.
Scenario: A 5-year-old female guinea pig presents with a history of anorexia, weight loss, and a rough hair coat. Urinalysis reveals a high urine specific gravity and the presence of protein. Radiographs show no evidence of uroliths.
Lead-in: Which of the following conditions is a common cause of chronic renal disease with proteinuria in guinea pigs?
Options:
a) Amyloidosis
b) Cystitis
c) Hydronephrosis
d) Pyelonephritis
e) Uterine infection
Answer: a) Amyloidosis
Explanation: Amyloidosis is a well-recognised cause of chronic renal disease and proteinuria in guinea pigs. Cystitis is a bladder infection and would typically present with haematuria and dysuria. Hydronephrosis is the swelling of a kidney due to a build-up of urine and is usually caused by an obstruction. Pyelonephritis is a bacterial infection of the kidney, and while it can cause proteinuria, amyloidosis is a more common chronic cause. Uterine infections primarily affect the reproductive tract.
Scenario: A 7-year-old male ferret presents with a history of lethargy, inappetence, and increased thirst and urination. On physical examination, the ferret has poor body condition and pale mucous membranes. Bloodwork reveals azotaemia and anaemia.
Lead-in: Which of the following is a less common but possible cause of chronic renal disease in ferrets that should be considered?
Options:
a) Adrenal gland disease
b) Insulinoma
c) Lymphoma
d) Dental disease leading to secondary renal amyloidosis
e) Gastric ulceration
Answer: c) Lymphoma
Explanation: While adrenal gland disease and insulinoma are common endocrine diseases in ferrets, lymphoma can affect various organs, including the kidneys, leading to renal dysfunction. Dental disease can lead to secondary amyloidosis, but this is less common than lymphoma affecting the kidneys. Gastric ulceration would typically present with gastrointestinal signs.
Scenario: A 10-year-old female budgerigar presents with a history of lethargy, fluffed feathers, and polyuria. On physical examination, the bird is thin, and the vent area is soiled with urates.
Lead-in: Which of the following is a common cause of renal disease in older budgerigars?
Options:
a) Hypovitaminosis A
b) Gout (urate deposition)
c) Lead toxicity
d) Bacterial nephritis
e) Testicular neoplasia causing compression
Answer: b) Gout (urate deposition)
Explanation: Visceral and articular gout, caused by the deposition of urate crystals, is a common finding in older budgerigars with renal disease due to their limited ability to concentrate urine. Hypovitaminosis A typically causes squamous metaplasia. Lead toxicity can cause various signs, including neurological and gastrointestinal. Bacterial nephritis is possible but gout is more prevalent in older birds. Testicular neoplasia is a possibility in male birds.
Scenario: A 4-year-old Hermann’s tortoise presents with a history of lethargy and anorexia for several days. On physical examination, the tortoise is dehydrated, and the pre-femoral fossae appear sunken. Urinalysis reveals a high level of urates.
Lead-in: While dehydration is a common cause of increased urates in tortoise urine, which of the following underlying conditions should also be considered as a primary renal disease?
Options:
a) Metabolic bone disease
b) Hypovitaminosis D3
c) Renal tubular necrosis secondary to aminoglycoside use
d) Shell rot
e) Respiratory tract infection
Answer: c) Renal tubular necrosis secondary to aminoglycoside use
Explanation: Aminoglycoside antibiotics are nephrotoxic and can cause renal tubular necrosis in reptiles, leading to renal disease. Dehydration is a very common cause of increased urates in tortoise urine, but a history of medication or other risk factors for nephrotoxicity should prompt consideration of primary renal disease. Metabolic bone disease and hypovitaminosis D3 are related to calcium and vitamin D metabolism. Shell rot is a bacterial or fungal infection of the shell. Respiratory tract infections are common in tortoises but do not directly cause increased urates in urine due to primary renal disease.
Scenario: A 2-year-old male Syrian hamster presents with a history of chronic intermittent diarrhoea and weight loss. On physical examination, the hamster is thin and has a slightly rough hair coat. Bloodwork reveals mild azotaemia.
Lead-in: Which of the following conditions, although primarily affecting the gastrointestinal tract, can sometimes lead to secondary renal amyloidosis in hamsters?
Options:
a) Tyzzer’s disease
b) Wet tail (proliferative ileitis)
c) Dental malocclusion
d) Dermatophytosis
e) Barbering
Answer: b) Wet tail (proliferative ileitis)
Explanation: Chronic inflammation associated with conditions like wet tail (proliferative ileitis) in hamsters can sometimes lead to secondary amyloidosis affecting various organs, including the kidneys. Tyzzer’s disease is caused by Clostridium piliforme and can affect multiple organs, including the liver and intestines. Dental malocclusion can cause weight loss but not typically renal amyloidosis. Dermatophytosis is a skin fungal infection. Barbering is a behavioural issue.
Scenario: A 6-month-old female chinchilla presents with a history of anorexia, lethargy, and a hunched posture. On physical examination, the chinchilla is dehydrated and has a painful abdomen on palpation. Urinalysis reveals haematuria.
Lead-in: While urinary tract infections and urolithiasis are possible in chinchillas, which of the following less common conditions should be considered in a young animal with haematuria and signs of renal involvement?
Options:
a) Malocclusion leading to oral pain and inappetence
b) Heatstroke
c) Nephroblastoma
d) Fungal pneumonia
e) Giardiasis
Answer: c) Nephroblastoma
Explanation: Nephroblastoma is a type of kidney cancer that can occur in young animals, including chinchillas, and can present with signs of renal disease such as haematuria. Malocclusion causes dental problems. Heatstroke presents with hyperthermia. Fungal pneumonia affects the respiratory system. Giardiasis is an intestinal parasite causing diarrhoea.
Scenario: A 4-year-old bearded dragon presents with a history of lethargy and weakness. Bloodwork reveals hyperphosphataemia and hypocalcaemia. Radiographs show generalised decreased bone density.
Lead-in: While these findings are consistent with metabolic bone disease, which of the following can be a contributing factor or a differential diagnosis involving renal dysfunction in reptiles?
Options:
a) Hypervitaminosis D3
b) Primary hyperparathyroidism
c) Secondary nutritional hyperparathyroidism due to inadequate UVB lighting
d) Renal secondary hyperparathyroidism
e) Gout
Answer: d) Renal secondary hyperparathyroidism
Explanation: Chronic renal disease can lead to decreased production of active vitamin D and impaired phosphate excretion, resulting in hyperphosphataemia, hypocalcaemia, and secondary hyperparathyroidism of renal origin. While nutritional secondary hyperparathyroidism due to inadequate UVB lighting is a common cause of metabolic bone disease, renal disease can also contribute to or mimic these signs. Hypervitaminosis D3 leads to hypercalcaemia. Primary hyperparathyroidism is rare in reptiles. Gout involves urate deposition
Scenario: A 2-year-old African grey parrot presents with a history of polyuria and polydipsia. Bloodwork reveals elevated uric acid levels.
Lead-in: Which of the following is a common cause of renal disease leading to hyperuricaemia in birds?
Options:
a) Hypothyroidism
b) Adrenal insufficiency
c) Lead or zinc toxicity
d) Pancreatitis
e) Cardiomyopathy
Answer: c) Lead or zinc toxicity
Explanation: Heavy metal toxicities, particularly lead and zinc, are well-known causes of renal damage in birds, leading to impaired uric acid excretion and hyperuricaemia. Hypothyroidism and adrenal insufficiency are less common in birds and have different primary clinical signs. Pancreatitis primarily affects the digestive system. Cardiomyopathy affects the heart.
Scenario: A 6-year-old female rabbit presents with a history of straining to urinate and producing small amounts of urine. Radiographs reveal a radiopaque calculus in the bladder.
Lead-in: Which type of urolith is most common in rabbits and is often associated with high dietary calcium?
Options:
a) Struvite
b) Urate
c) Cystine
d) Calcium oxalate
e) Silica
Answer: d) Calcium oxalate
Explanation: Calcium oxalate uroliths are the most common type of bladder stones found in rabbits and are often associated with a diet high in calcium. Rabbits absorb almost all dietary calcium, and excess is excreted in the urine. Other types of uroliths are less common in rabbits compared to other species.
Scenario: A 10-year-old female spayed Labrador Retriever presents with a history of polyuria, polydipsia, and weight loss over the past few weeks. Today, she is lethargic and has been vomiting. On physical examination, she is dehydrated and has a fruity odour to her breath.
Lead-in: Which of the following diagnostic tests would be most crucial in confirming the suspected diagnosis?
Options:
a) Complete blood count
b) Serum biochemistry panel including electrolytes
c) Urinalysis including assessment for ketones
d) Abdominal radiography
e) Blood pressure measurement
Answer: c) Urinalysis including assessment for ketones
Explanation: The history and clinical signs (polyuria, polydipsia, weight loss, lethargy, vomiting, fruity breath) are highly suggestive of diabetic ketoacidosis (DKA). The presence of ketones in the urine is a key diagnostic criterion for DKA, indicating the body is breaking down fat for energy, leading to the production of ketone bodies. While a serum biochemistry panel will show hyperglycaemia and electrolyte derangements, and a CBC might show changes related to dehydration or infection, the presence of ketones in the urine is the most specific finding for DKA.
Scenario: A cat is diagnosed with diabetic ketoacidosis. Initial blood glucose is too high to read on a glucometer (>33.3 mmol/L).
Lead-in: Besides hyperglycaemia, which of the following would be an expected finding on urinalysis in this cat?
Options:
a) Glucosuria and haematuria
b) Proteinuria and isosthenuria
c) Glucosuria and ketonuria
d) Bilirubinuria and pyuria
e) Crystalluria and a high urine specific gravity
Answer: c) Glucosuria and ketonuria
Explanation: In diabetic ketoacidosis, the lack of effective insulin leads to hyperglycaemia, exceeding the renal threshold for glucose reabsorption, resulting in glucosuria. Additionally, the body’s shift to fat metabolism due to lack of glucose utilisation leads to the production of ketone bodies, which are also excreted in the urine (ketonuria). Haematuria, proteinuria, bilirubinuria, pyuria, and crystalluria are not primary expected findings in uncomplicated DKA.
Scenario: A male cat with a urethral obstruction has been successfully unblocked. Post-obstructive bloodwork reveals a potassium level of 5.8 mmol/L. The ECG shows no significant abnormalities.
Lead-in: Based on this potassium level and lack of ECG changes, which of the following immediate treatments for hyperkalaemia is indicated?
Options:
a) Intravenous calcium gluconate
b) Intravenous regular insulin and dextrose
c) Intravenous sodium bicarbonate
d) No immediate treatment for hyperkalaemia is required
e) Subcutaneous terbutaline
Answer: d) No immediate treatment for hyperkalaemia is required
Explanation: According to the provided guidelines for feline urethral obstruction, treatment for hyperkalaemia is indicated when potassium levels are >7-8 mmol/L or when ECG changes are apparent. A potassium level of 5.8 mmol/L without ECG changes is elevated but does not require immediate aggressive treatment. The cat should be monitored, and further bloodwork should be performed to assess trends.
Scenario: A cat with diabetic ketoacidosis is being treated with intravenous fluids and insulin. The blood glucose level is decreasing too rapidly.
Lead-in: According to the provided material on DKA, what is the recommended maximum rate of reduction for blood glucose in mmol/L per hour to avoid complications?
Options:
a) <1 mmol/L/hour
b) <2 mmol/L/hour
c) <3 mmol/L/hour
d) <4 mmol/L/hour
e) <5 mmol/L/hour
Answer: c) <3 mmol/L/hour
Explanation: The provided material on DKA states that rapid correction of hyperglycaemia can lead to cerebral oedema. Therefore, the maximum recommended rate of reduction for blood glucose is <3 mmol/L per hour. The insulin dose should be adjusted if the glucose is decreasing too quickly.
Scenario: A male cat has been diagnosed with a urethral obstruction due to a urethral plug. The obstruction has been relieved, and an indwelling urinary catheter has been placed.
Lead-in: According to the provided algorithm for blocked bladders, which of the following analgesics is recommended as a first-line treatment for pain in this cat?
Options:
a) Buprenorphine
b) Ketamine
c) Methadone
d) Meloxicam
e) Fentanyl
Answer: c) Methadone
Scenario: A cat with diabetic ketoacidosis is being treated with intravenous fluids, and the blood glucose has decreased to 12 mmol/L. The cat is still ketotic and has a mild metabolic acidosis.
Lead-in: According to the provided material on DKA, what is the next most appropriate step in the insulin therapy for this cat?
Options:
a) Discontinue insulin therapy until blood glucose increases.
b) Continue the previous rate of insulin infusion.
c) Decrease the rate of insulin infusion and start supplementing the fluids with dextrose.
d) Increase the rate of insulin infusion to resolve ketosis more quickly.
e) Switch to subcutaneous insulin injections.
Answer: c) Decrease the rate of insulin infusion and start supplementing the fluids with dextrose.
Explanation: Once the blood glucose drops below a certain threshold (typically around 11-14 mmol/L), continuing the initial insulin infusion rate can lead to hypoglycaemia. The provided material on DKA suggests decreasing the insulin infusion rate and adding dextrose to the intravenous fluids to maintain blood glucose in a safe range while allowing continued insulin action to resolve ketosis and acidosis. Discontinuing insulin would lead to a rebound in glucose and worsening ketosis. Increasing the rate risks hypoglycaemia. Switching to subcutaneous insulin is not appropriate until the patient is more stable and eating.
Scenario: A dog with diabetic ketoacidosis is receiving intravenous fluid therapy. Bloodwork reveals persistent hypokalaemia despite supplementation in the fluids.
Lead-in: According to the provided material on DKA, what is the most likely reason for this persistent hypokalaemia in a patient with DKA?
Options:
a) Inadequate potassium supplementation in the intravenous fluids.
b) Ongoing losses of potassium through diarrhoea.
c) Intracellular shift of potassium due to insulin therapy.
d) Increased renal excretion of potassium due to hyperglycaemia.
e) Concurrent hyperaldosteronism.
Answer: c) Intracellular shift of potassium due to insulin therapy.
Explanation: While inadequate supplementation and losses can contribute to hypokalaemia, insulin therapy promotes the intracellular uptake of glucose and potassium via the Na+/K+-ATPase pump. This shift of potassium from the extracellular to the intracellular space is a common cause of hypokalaemia or persistent hypokalaemia during DKA treatment, even with supplementation. Hyperglycaemia can initially lead to osmotic diuresis and potassium loss, but during treatment with insulin, the intracellular shift becomes more significant. Concurrent hyperaldosteronism is less likely in this acute setting.
Scenario: A 6-year-old female neutered West Highland White Terrier presents with a history of intermittent haematuria for the past month. Urine culture was negative.
Lead-in: Based on the breed predisposition and clinical sign, which of the following conditions is a strong differential diagnosis?
Options:
a) Bacterial cystitis
b) Calcium oxalate urolithiasis
c) Transitional cell carcinoma of the bladder
d) Struvite urolithiasis
e) Glomerulonephritis
Answer: c) Transitional cell carcinoma of the bladder
Explanation: West Highland White Terriers have a known predisposition for transitional cell carcinoma (TCC) of the bladder. Intermittent haematuria with a negative urine culture is a common presentation for TCC. While calcium oxalate and struvite urolithiasis can cause haematuria, breed predisposition makes TCC more likely. Bacterial cystitis would typically have a positive urine culture. Glomerulonephritis usually presents with proteinuria.
Scenario: A cat with chronic kidney disease (CKD) is being considered for anaesthesia for a dental procedure. Bloodwork reveals a creatinine of 300 µmol/L (IRIS Stage 3).
Lead-in: According to the principles of anaesthesia for renal disease, which of the following is the most important consideration for this patient during the anaesthetic period?
Options:
a) Avoiding premedications
b) Maintaining adequate hydration and renal perfusion
c) Using only alpha-2 adrenergic agonists for sedation
d) Ensuring a very light plane of anaesthesia
e) Avoiding the use of volatile anaesthetic agents
Answer: b) Maintaining adequate hydration and renal perfusion
Explanation: Patients with renal disease have reduced ability to compensate for hypotensive episodes that can occur during anaesthesia. Maintaining adequate hydration with intravenous fluids and ensuring good renal perfusion are crucial to prevent further kidney damage. While careful drug selection and monitoring of anaesthetic depth are important, preserving renal function is paramount.
Scenario: A dog presents with haematuria, stranguria, and pollakiuria. Initial urinalysis reveals numerous red blood cells and white blood cells, but no bacteria.
Lead-in: According to the approach to haematuria and dysuria, what is the next most appropriate diagnostic step?
Options:
a) Prescribe antibiotics based on clinical signs.
b) Perform abdominal radiography to look for uroliths.
c) Perform urine culture and sensitivity.
d) Perform a coagulation profile.
e) Start treatment for idiopathic cystitis.
Answer: c) Perform urine culture and sensitivity.
Explanation: Even though no bacteria were seen on initial urinalysis, a urine culture and sensitivity test is essential to rule out a bacterial urinary tract infection, especially with the presence of white blood cells. Radiography is useful for detecting radiopaque uroliths, and a coagulation profile might be indicated if there’s concern for a bleeding disorder, but ruling out infection is a primary step. Empiric antibiotic treatment without culture is not best practice, and idiopathic cystitis is a diagnosis of exclusion.
Scenario: A cat with a history of calcium oxalate urolithiasis is being managed with a prescription diet.
Lead-in: According to the nutritional support for feline lower urinary tract disease, what is a key goal of the diet in preventing recurrence of this type of urolith?
Options:
a) To acidify the urine.
b) To increase the concentration of magnesium and phosphorus in the urine.
c) To promote a high urine specific gravity.
d) To promote a urine pH that is not excessively alkaline.
e) To restrict water intake to increase urine concentration of inhibitors.
Answer: d) To promote a urine pH that is not excessively alkaline.
Explanation: Calcium oxalate stones form more readily in acidic to neutral urine. While alkalinising diets are used for some urolith types, for calcium oxalate, the goal is to avoid excessive alkalinity which can paradoxically increase the risk in some cases. Maintaining adequate hydration to lower urine specific gravity is also crucial.
Scenario: A dog has undergone a cystotomy for removal of multiple bladder stones. Analysis of the stones reveals they are struvite.
Lead-in: According to the information on urolithiasis, what is the most likely underlying cause for the formation of struvite uroliths in dogs?
Options:
a) A diet high in calcium.
b) A genetic predisposition to urate metabolism.
c) Urinary tract infection with urease-producing bacteria.
d) A metabolic defect leading to cystine excretion.
e) Consumption of silica-rich soil.
Answer: c) Urinary tract infection with urease-producing bacteria.
Explanation: In dogs, struvite uroliths are most commonly associated with urinary tract infections caused by bacteria that produce the enzyme urease. Urease breaks down urea in the urine, leading to an increase in ammonia and an alkaline urine pH, which favours the precipitation of magnesium ammonium phosphate (struvite).
Scenario: A cat with chronic kidney disease (IRIS Stage 4) is anorexic and losing weight.
Lead-in: According to the nutritional support guidelines for CKD, which of the following dietary modifications is most important for managing this cat’s condition?
Options:
a) Increasing protein intake to prevent muscle wasting.
b) Restricting sodium intake to prevent hypertension.
c) Restricting phosphorus intake to slow the progression of CKD.
d) Supplementing with calcium to prevent renal secondary hyperparathyroidism.
e) Feeding a highly acidic diet to prevent urolithiasis.
Answer: c) Restricting phosphorus intake to slow the progression of CKD.
Explanation: Dietary phosphorus restriction is a cornerstone of nutritional management for cats with IRIS Stage 3 and 4 CKD. High phosphorus levels can exacerbate renal secondary hyperparathyroidism and are thought to contribute to the progression of kidney disease. While other modifications like palatable, calorie-dense food and potentially protein restriction are also important, phosphorus restriction has a strong evidence base for slowing CKD progression.
Scenario: A dog is undergoing anaesthesia for a nephrectomy due to renal neoplasia.
Lead-in: According to the principles of anaesthesia for renal disease, what is a critical aspect of intraoperative monitoring for this patient?
Options:
a) Monitoring blood glucose levels every 15 minutes.
b) Continuous electrocardiogram (ECG) and blood pressure monitoring.
c) Monitoring end-tidal carbon dioxide (ETCO2) only.
d) Monitoring body temperature every 30 minutes.
e) Palpating peripheral pulses every 10 minutes.
Answer: b) Continuous electrocardiogram (ECG) and blood pressure monitoring.
Explanation: Continuous monitoring of ECG and blood pressure is essential during anaesthesia, especially in patients with underlying conditions like renal disease or those undergoing major surgery such as a nephrectomy. This allows for early detection and management of cardiovascular instability and ensures adequate perfusion to the remaining kidney.
What is the medical term for producing small amounts of urine?
Oliguria
Scenario: A dog with known urate urolithiasis is being managed medically.
Lead-in: According to the information on urolithiasis, which of the following dietary modifications is recommended for the prevention of urate stones?
Options:
a) A diet high in purines.
b) A diet that promotes acidic urine.
c) A high moisture, alkalinising diet.
d) A diet restricted in magnesium and ammonium.
e) Supplementation with vitamin C.
Answer: c) A high moisture, alkalinising diet.
Explanation: Urate stones form more readily in acidic urine. Therefore, a high moisture diet that promotes alkaline urine is recommended to increase urine volume and the solubility of urate. Some dogs may also require medication like allopurinol to reduce uric acid production.
Scenario: A cat is undergoing anaesthesia for a renal biopsy.
Lead-in: What is a major prerequisite before performing a renal biopsy or nephrectomy?
Options:
a) The patient must be polyuric.
b) The patient must be normotensive.
c) Normal function of the contralateral kidney is a prerequisite for performing nephrectomy (and strongly recommended for biopsy).
d) The patient must have a urine specific gravity >1.030.
e) The patient must have a normal platelet count.
Answer: c) Normal function of the contralateral kidney is a prerequisite for performing nephrectomy (and strongly recommended for biopsy).
Explanation: It is crucial to ensure that the remaining kidney has adequate function before performing a nephrectomy. While not an absolute contraindication for biopsy, it is a very important consideration to minimise the risk of causing acute renal failure if the biopsied kidney has significant underlying disease.
Scenario: A dog with a history of recurrent calcium oxalate urolithiasis is being managed with dietary therapy.
Lead-in: What urine specific gravity is generally aimed for in dogs to help prevent recurrence of calcium oxalate stones?
Options:
a) <1.010
b) <1.020
c) <1.030
d) <1.040
e) <1.050
Answer: b) <1.020
Explanation: Maintaining a low urine specific gravity (<1.020 in dogs) is recommended for the prevention of calcium oxalate uroliths as it indicates more dilute urine, reducing the supersaturation of calcium and oxalate.
Scenario: A dog has a urethral obstruction due to a calculus lodged in the urethra.
Lead-in: What is a surgical procedure that might be necessary to relieve this obstruction if retrograde flushing is unsuccessful?
Options:
a) Cystotomy
b) Nephrotomy
c) Ureterotomy
d) Urethrostomy
e) Pyelolithotomy
Answer: d) Urethrostomy
Explanation: If a urethral obstruction in a male dog cannot be relieved by retrograde flushing, a urethrostomy, which creates a permanent opening in the urethra proximal to the obstruction, may be necessary to allow urination.
Scenario: A dog with a bladder mass is undergoing staging for urinary tract neoplasia.
Lead-in: What is the most common site for metastasis of bladder tumours in dogs?
Options:
a) Liver
b) Spleen
c) Lungs
d) Brain
e) Bone marrow
Answer: c) Lungs
Explanation: Urinary tract tumours, particularly transitional cell carcinoma, in dogs commonly metastasise to the lungs. Therefore, thoracic radiographs are an important part of the staging process.
Scenario: A cat with feline idiopathic cystitis (FIC) is experiencing recurrent episodes of lower urinary tract signs.
Lead-in: What is a key recommendation to help manage FIC?
Options:
a) Feeding a diet high in dry matter to promote urine concentration.
b) Restricting water intake to reduce bladder distension.
c) Encouraging increased water consumption, ideally with canned food.
d) Supplementing with high levels of magnesium to reduce crystal formation.
e) Feeding a highly acidic diet to prevent all types of uroliths.
Answer: c) Encouraging increased water consumption, ideally with canned food.
Explanation: Increasing water intake is a crucial aspect of managing FIC as it helps to dilute the urine, potentially reducing the concentration of irritants in the bladder. Feeding canned food, which has a higher moisture content than dry food, is an effective way to increase water consumption in cats.
Scenario: A cat is undergoing surgery for removal of a ureteral obstruction due to a urolith.
Lead-in: What is a potential surgical option for managing recurrent ureteral obstructions that may be considered if standard ureterotomy is not feasible?
Options:
a) Cystotomy
b) Nephrectomy
c) Urethrostomy
d) Subcutaneous ureteral bypass system (SUBS)
e) Pyelotomy
Answer: d) Subcutaneous ureteral bypass system (SUBS)
Explanation: The subcutaneous ureteral bypass system (SUBS) is a surgical alternative for managing ureteral obstructions, particularly in cases of recurrent obstruction or when traditional surgical repair is not possible. It involves placing a shunt from the renal pelvis to the bladder, bypassing the ureter.
