NAVLE General Practice 5 — Questions and Answers
Question 1: A 3-year-old Labrador Retriever ingested approximately 6 mg/kg of acetaminophen 2 hours ago. It is asymptomatic. What is the most appropriate treatment?
- N-acetylcysteine and supportive care (Correct answer)
- Induced emesis only
- Activated charcoal alone
- Vitamin K1 administration
Correct answer: N-acetylcysteine and supportive care
N-acetylcysteine replenishes glutathione stores and is the antidote for acetaminophen toxicity; it should be combined with supportive care even in an asymptomatic patient presenting within 4 hours of ingestion.
Question 2: A 6-year-old indoor-outdoor cat presents with a 2 cm subcutaneous mass over the interscapular region that appeared 3 months after vaccination. Histopathology shows a high-grade spindle cell tumor with inflammation at the periphery. The diagnosis is:
- Feline injection-site sarcoma (FISS) (Correct answer)
- Mast cell tumor
- Fibrosarcoma unrelated to injection
- Lipoma with atypical features
Correct answer: Feline injection-site sarcoma (FISS)
Feline injection-site sarcoma is an aggressive high-grade spindle cell tumor arising at vaccination or injection sites, characterized by peripheral inflammation and a high recurrence rate after excision.
Question 3: An alpaca presents with progressive weight loss, bottle jaw, and anemia. Fecal flotation reveals strongyle-type eggs. Which anthelmintic class is most commonly used as first-line therapy in camelids with suspected Haemonchus?
- Benzimidazoles (e.g., fenbendazole)
- Macrocyclic lactones (e.g., ivermectin) (Correct answer)
- Imidazothiazoles (e.g., levamisole)
- Salicylanilides (e.g., closantel)
Correct answer: Macrocyclic lactones (e.g., ivermectin)
Macrocyclic lactones such as ivermectin are commonly used first-line in camelids for Haemonchus contortus, though resistance monitoring via fecal egg count reduction tests is recommended.
Question 4: A 5-year-old dog presents with peracute collapse, pale mucous membranes, and abdominal distension. FAST ultrasound reveals free abdominal fluid and a splenic mass. PCV is 18%. Which statement is most accurate regarding the splenic mass?
- Approximately 50% of splenic masses in dogs are malignant (hemangiosarcoma) (Correct answer)
- Most splenic masses in dogs are benign hematomas
- Fine needle aspirate is diagnostic in the majority of splenic masses
- Splenectomy is contraindicated until coagulopathy is corrected
Correct answer: Approximately 50% of splenic masses in dogs are malignant (hemangiosarcoma)
In dogs with splenic masses and hemoabdomen, approximately 50% are hemangiosarcoma (malignant), 25% are other malignancies, and only 25% are benign nodular hyperplasia or hematoma.
Question 5: A 10-day-old foal presents with hypopyon, corneal vascularization, and joint effusion in the right tarsus. The most likely underlying cause is:
- Failure of passive transfer leading to septicemia (Correct answer)
- Rhodococcus equi pneumonia
- Neonatal isoerythrolysis
- Herpesvirus-1 ocular infection
Correct answer: Failure of passive transfer leading to septicemia
Septicemia secondary to failure of passive transfer is the leading cause of uveitis and septic arthritis in neonatal foals, as bacteria seed synovial and ocular tissues hematogenously.
Question 6: A dog is diagnosed with immune-mediated hemolytic anemia (IMHA). Which finding on the CBC is most specific for confirming immune-mediated destruction?
- Spherocytosis on blood smear (Correct answer)
- Macrocytosis and polychromasia
- Neutrophilia with a left shift
- Thrombocytopenia
Correct answer: Spherocytosis on blood smear
Spherocytes, which lack the normal biconcave shape due to partial phagocytosis of antibody-coated membrane by macrophages, are the most specific morphologic finding for IMHA.
Question 7: A poultry flock develops acute respiratory distress, cyanosis of the comb and wattles, and hemorrhagic tracheitis with 40% mortality over 5 days. Which disease is most consistent with these findings?
- Infectious laryngotracheitis (ILT) (Correct answer)
- Newcastle disease (velogenic form)
- Avian influenza (HPAI)
- Infectious bronchitis
Correct answer: Infectious laryngotracheitis (ILT)
Infectious laryngotracheitis, caused by Gallid alphaherpesvirus 1, presents with severe hemorrhagic tracheitis, bloody mucus, gasping, and high mortality in affected flocks.
NAVLE General Practice 5
A 3-year-old Labrador Retriever ingested approximately 6 mg/kg of acetaminophen 2 hours ago.
It is asymptomatic.
What is the most appropriate treatment?