NAVLE Canine Internal Medicine Questions and Answers — Questions and Answers
Question 1: A 7-year-old female spayed Standard Poodle presents with a history of waxing and waning lethargy, vomiting, and anorexia. On physical examination, she is quiet but responsive, with a heart rate of 60 bpm and weak femoral pulses. Bloodwork reveals hyponatremia, hyperkalemia, and azotemia. Which of the following is the most definitive diagnostic test for this dog's suspected condition?
- Endogenous ACTH concentration
- Low-dose dexamethasone suppression test
- Abdominal ultrasound
- ACTH stimulation test (Correct answer)
Correct answer: ACTH stimulation test
The clinical signs (lethargy, vomiting, anorexia), signalment (Standard Poodle), and classic electrolyte abnormalities (hyponatremia, hyperkalemia) are highly suggestive of hypoadrenocorticism (Addison's disease). The definitive diagnosis of hypoadrenocorticism is made by performing an ACTH stimulation test, which will show a low resting cortisol and a negligible response to ACTH administration.
Question 2: Which of the following is a primary therapeutic goal in the management of a dog with chronic kidney disease (CKD) and proteinuria?
- Increasing dietary protein to counteract losses
- Administering loop diuretics to increase GFR
- Controlling systemic hypertension and reducing phosphorus intake (Correct answer)
- Supplementing with high doses of Vitamin D to manage secondary hyperparathyroidism
Correct answer: Controlling systemic hypertension and reducing phosphorus intake
Management of canine CKD focuses on slowing disease progression and improving quality of life. Key goals include controlling systemic hypertension, which can exacerbate kidney damage, and reducing dietary phosphorus intake to manage renal secondary hyperparathyroidism. Protein restriction (not increase) is often indicated, and while diuretics have a role in specific situations, they don't increase GFR. Vitamin D supplementation must be done cautiously to avoid hypercalcemia.
Question 3: A 5-year-old Cocker Spaniel presents with acute lethargy, pale mucous membranes, and icterus. A complete blood count reveals a severe regenerative anemia (HCT 15%) with marked spherocytosis and autoagglutination. Which of the following is the most likely diagnosis?
- Zinc toxicity
- Immune-Mediated Hemolytic Anemia (IMHA) (Correct answer)
- Babesiosis
- Von Willebrand's disease
Correct answer: Immune-Mediated Hemolytic Anemia (IMHA)
The combination of severe regenerative anemia, spherocytosis, and autoagglutination is pathognomonic for Immune-Mediated Hemolytic Anemia (IMHA). Spherocytes are red blood cells that have lost their biconcave shape due to partial phagocytosis, a hallmark of extravascular hemolysis in IMHA. Autoagglutination is the macroscopic clumping of red blood cells due to antibody coating. While other conditions can cause anemia, this specific combination of findings points strongly to an immune-mediated process.
Question 4: A 10-year-old Miniature Schnauzer with a history of hyperlipidemia presents with acute onset of vomiting, anorexia, and cranial abdominal pain. Physical examination reveals a 'praying posture.' Laboratory findings include neutrophilia, elevated amylase, and markedly elevated lipase. Which of the following is the most appropriate initial treatment?
- Immediate exploratory laparotomy
- High-fat, high-protein diet to stimulate appetite
- Broad-spectrum antibiotics and oral corticosteroids
- Aggressive intravenous fluid therapy, analgesia, and antiemetics (Correct answer)
Correct answer: Aggressive intravenous fluid therapy, analgesia, and antiemetics
The signalment, history, and clinical signs are classic for acute pancreatitis. The cornerstone of treatment is supportive care, which includes aggressive intravenous fluid therapy to correct dehydration and maintain pancreatic perfusion, potent analgesia to manage pain, and antiemetics to control vomiting. A low-fat diet is indicated once the patient can tolerate oral intake, and surgery is not typically the first-line treatment unless complications like an abscess or obstruction are present.
Question 5: A 4-year-old Soft Coated Wheaten Terrier is presented for chronic small bowel diarrhea, significant weight loss, and peripheral edema. Bloodwork reveals severe panhypoproteinemia (both albumin and globulin are low). Which of the following conditions is the most likely underlying cause?
- Exocrine pancreatic insufficiency (EPI)
- Protein-losing nephropathy
- Chronic hepatitis
- Protein-losing enteropathy (PLE) (Correct answer)
Correct answer: Protein-losing enteropathy (PLE)
The combination of chronic diarrhea, weight loss, and panhypoproteinemia (low albumin and globulin) is characteristic of a protein-losing enteropathy (PLE). In PLE, proteins are lost through the gastrointestinal tract. While protein-losing nephropathy and chronic hepatitis cause hypoalbuminemia, globulins are typically normal or elevated. EPI causes weight loss and diarrhea but does not typically cause significant protein loss. Soft Coated Wheaten Terriers are also predisposed to PLE.
Question 6: Which of the following is considered the most effective method for long-term monitoring of glycemic control in a diabetic dog, reflecting average blood glucose over the preceding 2-3 months?
- Urine glucose strips
- Serial blood glucose curve
- Fructosamine concentration
- Glycosylated hemoglobin (HbA1c) concentration (Correct answer)
Correct answer: Glycosylated hemoglobin (HbA1c) concentration
Glycosylated hemoglobin (HbA1c) is formed by the irreversible binding of glucose to hemoglobin within red blood cells. Its concentration reflects the average blood glucose level over the lifespan of the erythrocyte (approximately 2-3 months in dogs), making it an excellent tool for assessing long-term glycemic control and less susceptible to short-term fluctuations from stress or diet. Fructosamine reflects control over the preceding 2-3 weeks. Glucose curves and urine strips only provide a snapshot of glucose levels at a specific point in time.
NAVLE Canine Internal Medicine Questions and Answers
A 7-year-old female spayed Standard Poodle presents with a history of waxing and waning lethargy, vomiting, and anorexia.
On physical examination, she is quiet but responsive, with a heart rate of 60 bpm and weak femoral pulses.
Bloodwork reveals hyponatremia, hyperkalemia, and azotemia.
Which of the following is the most definitive diagnostic test for this dog's suspected condition?