NAVLE Canine Internal Medicine 5 — Questions and Answers
Question 1: A 6-year-old Miniature Poodle has chronic small bowel diarrhea. Serum TLI is 2.0 µg/L (normal >2.5 µg/L). What is the most likely diagnosis?
- Inflammatory bowel disease
- Exocrine pancreatic insufficiency (Correct answer)
- Lymphangiectasia
- Intestinal lymphoma
Correct answer: Exocrine pancreatic insufficiency
A serum TLI below 2.5 µg/L is diagnostic for exocrine pancreatic insufficiency, reflecting markedly reduced pancreatic enzyme secretion.
Question 2: A 9-year-old Labrador Retriever is diagnosed with stage 3 chronic kidney disease (IRIS). Serum phosphorus is 6.8 mg/dL. Which intervention is most important to slow CKD progression?
- Phosphate restriction and phosphate binders (Correct answer)
- Increased protein supplementation
- Sodium restriction alone
- IV fluid diuresis three times weekly
Correct answer: Phosphate restriction and phosphate binders
Phosphate restriction through diet and phosphate binders reduces renal mineralization and is one of the most evidence-based strategies to slow CKD progression.
Question 3: A 4-year-old Labrador Retriever presents with acute respiratory distress after ingesting rat poison 2 days ago. PT and aPTT are severely prolonged; patient has pleural hemorrhage. Which rodenticide is most likely responsible?
- Bromethalin
- Zinc phosphide
- Brodifacoum (second-generation anticoagulant) (Correct answer)
- Strychnine
Correct answer: Brodifacoum (second-generation anticoagulant)
Second-generation anticoagulant rodenticides like brodifacoum inhibit vitamin K epoxide reductase, causing prolonged coagulopathy and hemorrhage 1–5 days post-ingestion.
Question 4: A 5-year-old Poodle presents with acute collapse, pale mucous membranes, and distended abdomen. Ultrasound reveals a large hepatic mass with free abdominal fluid. Which tumor is most commonly associated with hemoabdomen in dogs?
- Hepatocellular carcinoma
- Hemangiosarcoma (Correct answer)
- Mast cell tumor
- Lymphoma
Correct answer: Hemangiosarcoma
Hemangiosarcoma of the spleen or liver is the most common cause of spontaneous hemoabdomen in dogs due to its highly vascular and fragile nature.
Question 5: A 7-year-old intact female Boxer presents with polyuria, polydipsia, and a serum sodium of 157 mEq/L. She is not pregnant. Endogenous ACTH stimulation test is normal. Which diagnosis is most consistent with these findings?
- Hyperadrenocorticism
- Diabetes insipidus
- Diestrus-associated acromegaly or progesterone-induced GH excess (Correct answer)
- Primary hyperaldosteronism
Correct answer: Diestrus-associated acromegaly or progesterone-induced GH excess
Progesterone during diestrus stimulates mammary GH secretion in intact females, causing insulin resistance, PU/PD, and hypernatremia (acromegaly-like syndrome).
Question 6: A 5-year-old Great Dane presents with sudden gastric dilation. Radiographs confirm gastric dilatation-volvulus (GDV). After stabilization and surgery, which procedure should be performed concurrently to prevent recurrence?
- Esophageal banding
- Gastropexy (Correct answer)
- Splenectomy in all cases
- Pyloromyotomy
Correct answer: Gastropexy
Gastropexy permanently affixes the stomach to the body wall and reduces GDV recurrence from ~70–80% to less than 5%.
Question 7: An 11-year-old Cocker Spaniel with mitral valve disease is now in CHF (NYHA functional class III). Which combination of drugs is considered standard of care per the ACVIM 2019 consensus guidelines for dogs with CHF?
- Furosemide + atenolol + digoxin
- Furosemide + pimobendan + enalapril (Correct answer)
- Pimobendan + digoxin + spironolactone
- Amlodipine + furosemide + atenolol
Correct answer: Furosemide + pimobendan + enalapril
The ACVIM 2019 consensus recommends furosemide, pimobendan, and an ACE inhibitor as the core triple therapy for dogs in CHF due to myxomatous mitral valve disease.
NAVLE Canine Internal Medicine 5
A 6-year-old Miniature Poodle has chronic small bowel diarrhea.
Serum TLI is 2.0 µg/L (normal >2.5 µg/L).
What is the most likely diagnosis?