Dogs II Flashcards
What condition that is common in the breed of dog shown might predispose them to what you see in the photograph?
- Congenital hypertension
- von Willbrand’s Disease
- Dilated Cardiomyopathy
- Hemophilia B
Answer: von Willbrand’s Disease
Explanation
The correct answer is von Willebrand’s disease.
Hopefully, you were able to identify this image as a Doberman Pinscher with epistaxis, and you recalled that von Willebrand’s disease is common in this breed. This is a condition that results in poor primary hemostasis (formation of a platelet plug) due to a loss of von Willebrand’s factor, which is critical for allowing platelets to adhere to sites of hemorrhage.
Dilated cardiomyopathy is also common to Dobermans but results in conduction abnormalities, heart failure, and sudden death rather than epistaxis. Hemophilia B and hypertension can cause epistaxis but are not known to be a problem in the Doberman breed.
A 5-year old male castrated Chihuahua mix presents with a 2 day history of limping in the hind limbs. The owner reports that he is usually very active and now he seems very hesitant to jump on and off of the couch. On physical exam, the patient appears to be slightly weak in the hind, reminiscent of a drunken gait. There are no conscious proprioceptive deficits. The patellar and gastrocnemius reflexes are normal. There is resistance noted when turning the neck to the left and pain elicited on deep neck palpation. Mentation is appropriate and the cranial nerves are intact. The owners have financial concerns and can only afford limited treatment and diagnostics. In light of these constraints, what is the best treatment option?
- Tramadol and acepromazine with strict rest
- Non-steroidal anti-inflammatory therapy and strict rest
- Intravenous dexamethasone sodium phosphate at 6 hour intervals for 36 hours and strict rest
- Immunosuppressive doses of prednisone with
strict rest
Answer: Non-steroidal anti-inflammatory therapy and strict rest
Explanation
The most recent literature shows that 50% of dogs with clinical signs of intervertebral disc disease will improve with medical management alone. Medical management involves restricted activity and anti-inflammatory therapy.
Prednisone, methyl-prednisolone sodium succinate, and non-steroidal anti-inflammatories are commonly used.
Prednisone, if used, should be prescribed at an anti-inflammatory dose and not
immunosuppressive. Dexamethasone sodium phosphate has only been shown to increase the likelihood of side effects and complications such as urinary tract infection and is therefore not recommended.
A 2.5-year old miniature Schnauzer presents for further evaluation as a result of stranguria. Abdominal ultrasound identified uroliths and the dog was taken to surgery for a cystotomy. Stone analysis revealed urate stones. You call the owners to inform them of the results and recommend which diagnostic test?
- Low dose dexamethasone suppression test
- Creatine kinase levels
- ACTH stimulation test
- Pre- and post-prandial bile acids test
Answer: Pre- and post-prandial bile acids test
Explanation
Urate stones in a small breed dog are usually secondary to a portosystemic shunt until proven otherwise. A portosystemic shunt results in blood from the abdomen being shunted away from the liver and into the main circulation. If shunted, the liver does not have an opportunity to detoxify the blood, which among other toxins, is very high in ammonia. The excess ammonia is excreted via the kidneys. High levels of ammonia can result in formation of ammonium biurate crystals and ultimately stones.
An ACTH stimulation test is used to help diagnose hypoadrenocorticism and hyperadrenocorticism. A low dose dexamethasone test is used to help diagnose hyperadrenocorticism. Creatine kinase levels are evaluated when there is a suspected myopathy.
***PowerLecture: Portosystemic Shunts
What changes are seen on electroretinogram (ERG) with sudderaceuired retinal degeneration syndrome (SARDS) in dogs?
- Decreased ERG amplitude (weakened response
- Normal ERG amplitude
- Flat-line ERG (no response)
- Increased ERG amplitude (exaggerated
response)
Answer: Flat-line ERG (no response)
Explanation
The correct answer is flat-line ERG. By definition, an animal with SARDS has a flat-line ERG from day 1 of onset of the condition
A dog presents with a nonspecific history of slightly decreased appetite, lethargy, and odd behavior. A leukogram shows the following values:
WBC 22,385 cells/uL (5,000-14,000 cells/uL) band neutrophils 100 cells/uL (0-450 cells/uL)
segmented neutrophils 20,432 cells/uL (2,900-12,000 cells/uL)
lymphocytes 382 cells/uL (400-2,900 cells/uL) monocytes 1552 cells/uL (100-1,400 cells/uL)
eosinophils 9 cells/uL (0-1,300 cells/uL)
basophils 5 cells/uL (0-140 cells/uL)
What is your interpretation of the leukogram?
- Normal
- Left shift
- Stress leukogram
- Infection
- Degenerative left shift
Answer: Stress leukogram
Explanation
The correct answer is stress leukogram. You can see the classic mild neutrophilia along with lymphopenia and monocytosis. Although there are bands present in the blood work, this is a normal amount according to reference levels provided and is thereby not considered a left shift.
A 6-month old Labrador Retriever presents for failure to thrive and stranguria. Abdominal ultrasound shows a small liver and stones in the urinary bladder. Abdominal radiographs show no visible stones. How can this be explained?
- The dog has calcium oxalate stones.
- The dog has struvite stones.
- An artifact from the ultrasound was perceived as stones. There are really no stones in the bladder.
- The dog has urate stones in its bladder.
Answer: The dog has urate stones in its bladder.
Explanation
The correct answer is the dog has urate stones. The dog is described as having a portosystemic shunt which is often accompanied by urate stones in the bladder. Urate stones (and cysteine stones) are radiolucent, so they can’t be detected by radiography. Remember “I can’t C U”: (“C” is for cysteine, and “U” is for urate).
***PowerPage: Urolithiasis
Two 9-year old female spayed Labrador retrievers presented for their next chemotherapy treatments. Both were diagnosed with multicentric lymphoma and have been receiving the CHOP protocol. One received doxorubicin (Adriamycin) and one received vincristine (Oncovin) today. Your technician informs you that both unfortunately had extravasations occur and wants to know what she should do. Which drug is a worse vesicant and what should be done to the injection site?
- Doxorubicin. Cold compress to contain the spread of drug
- Vincristine. Cold compress to contain the spread of drug
- Doxorubicin. Warm compress to disperse the drug
- Vincristine. Warm compress to disperse the drug
Answer: Doxorubicin. Cold compress to contain the spread of drug
Explanation
Intravenous chemotherapy drugs can cause severe tissue necrosis (doxorubicin) or irritation (vincristine) if extravasation occurs. Treatment for both should begin immediately. In both cases, the catheter should be left in place and as much of the drug should be aspirated as possible. Treatment for doxorubicin extravasation involves cold compressing the site to promote vasoconstriction, however perivascular necrosis may still occur and may progress days to weeks later. In severe cases involving doxorubicin, debridement or limb amputation may be needed.
Vincristine extravasation should be treated with warm compresses to disperse the drug and enhance systemic absorption.
Extravasation should be prevented through patient restraint training, use of catheters that have been placed on the first stick, and careful monitoring during administration. The peripheral veins should be avoided for blood draws if possible on all patients receiving chemotherapy.
A 5-year old female Golden Retriever presents for lethargy, dark runny stool, and dehydration. Bloodwork from yesterday showed markedly elevated plasma endogenous ACTH levels, K+ = 6.2 (3.9-5.1 mEq/L), Na+= 135 (142-152 mEq/L), BUN = 62 mg/dl (8-28 mg/dl). Long-term maintenance therapy for this patient should most likely include:
- Mineralocorticoid, glucocorticoid, and NaCl supplementation
- IV fluids and daily doses of IV dexamethasone sodium phosphate
- Mineralocorticoid supplementation alone
- Supplementation with physiologic doses of prednisone
Answer: Mineralocorticoid, glucocorticoid, and NaCl supplementation
Explanation
The correct answer is mineralocorticoid, glucocorticoid, and NaCl supplementation. This dog has hypoadrenocorticism which is usually a deficiency in both glucocorticoids and mineralocorticoids. Elevated endogenous plasma ACTH concentrations with hypoadrenocorticism means the disease is due to primary adrenocortical insufficiency and failure to produce both types of corticosteroids (as opposed to secondary adrenocortical insufficiency, when the pituitary does not produce sufficient ACTH). Maintenance treatment of this disease includes supplementation with mineralocorticoids (e.g. Fludrocortisone acetate), glucocorticoids (e.g. Prednisone), and sodium chloride in the diet. IV fluids and dexamethasone sodium phosphate is used in an acute crisis.
***PowerPage: Hypoadrenocorticism (Addison’s Disease)
The five-year old female Doberman Pincher in the photo below whelped 8 puppies 4 weeks ago. She presents to you dehydrated and lethargic with temperature of 104.9 F (40.5 C). Her left inguinal mammary gland is hard, painful, hot, and reddish purple as seen in the image. What is the most likely diagnosis?
- Mastitis
- Pyometra
- Mammary carcinoma
- Gynecomastia
- Hypocalcemia
Answer: Mastitis
Explanation
With the recent history of whelping, fever, and a firm, red, painful mammary gland, the most likely diagnosis is mastitis. The puppies should be removed and weaned and warm compresses applied to the gland to promote draining. Antibiotics that penetrate the barrier between the bloodstream and mammary gland should be considered such as trimethoprim-sulfa, clindamycin, and cephalosporins.
An 8-year old female Chow Chow presents to you for difficulty eating. On oral exam, you see a 3 cm mass in the caudal maxilla. You are unable to obtain a fine needle aspirate because of the mass’s location but you detect an enlarged mandibular lymph node and aspirate it. A representative field from the aspirate is shown in the image below. In addition to surgery (+/- radiation), which of the following is an APPROVED treatment option for this disease that you would mention to the owner?
- Mitoxantrone
- Doxorubicin
- Palladia
- ONCEPT vaccine
- Vincristine
Answer: ONCEPT vaccine
Explanation
The image shows a lymph node with metastatic melanoma (the large cell with black melanin pigment). The ONCEPT vaccine, also commonly referred to as the “melanoma vaccine” was given a conditional product license in 2007 and was USDA approved in 2010 as a therapeutic vaccine for cancer treatment.
Palladia is a receptor tyrosine kinase inhibitor approved for use in mast cell tumors in dogs. Doxorubicin, vincristine and mitoxantrone are human chemotherapy drugs commonly used off-label in veterinary oncology but not routinely for melanoma.
***PowerPage: Oral Melanoma
A 5-month old Yorkshire Terrier presents for failure to thrive and ataxia of 2 days duration. A chemistry panel shows a bilirubin of 0.9 mg/dL (0-0.3 mg/dl), BUN of 5.2 mg/dL (8-28 mg/d). Which of the following is most likely in this dog?
- Multiple intra-hepatic portosystemic shunts
- End stage liver disease due to fibrosis
- Multiple extra-hepatic portosystemic shunts
- A single intra-hepatic portosystemic shunt
- A single extra-hepatic portosystemic shunt
Answer: A single extra-hepatic portosystemic shunt
Explanation
The correct answer is a single extra-hepatic portosystemic shunt. Toy breed dogs, particularly Yorkshire Terriers, are predisposed to congenital, single, extra-hepatic portosystemic shunts. Larger breed dogs with congenital liver shunts tend to develop intrahepatic shunts. Acquired shunts in older animals are almost always extrahepatic.
***PowerPage: Portosystemic Shunt
***PowerLecture: Portosystemic Shunts
and weaknes. You perform intial boodwork and find that her blood pH is 7.6 (735-745) and her potassium is 1.8 mmol/L (3.4-4.9 mmol/L). She weighs 12 kg. You immediately start her on intravenous fluids supplemented with potassium. What is the maximum rate of intravenous potassium that would be considered safe to administer to this dog?
- 12 mEq/hr
- 18 mEq/hr
- 3 mEq/hr
- 24 mEq/hr
- 6 mEq/hr
Answer: 6 mEq/hr
Explanation
The maximum safe rate of potassium infusion is 0.5 mEq/kg/hr. As this dog weighs 12 kg, the maximum is 6 mEq/hr. This is one of those rates that you need to know. Administering potassium more rapidly than this can result in fatal arrhythmias.
A 10-year old Shih Tzu presents for collapse. A diagnostic work up shows a mass on the right kidney, which was subsequently removed and biopsied as renal carcinoma. Which one of the following can be associated with renal carcinoma?
- Hyperadrenocorticism
- Polycythemia
- Hypercalcemia
- Thrombocytopathy
- Hyperestrogenism
Answer: Polycythemia
Explanation
Renal carcinomas have been associated with erythropoietin secretion, causing elevations in hematocrit as a paraneoplastic syndrome.
Hypercalcemia is associated with anal sac adenocarcinomas, lymphomas and other tumors.
Thrombocytopathy can be seen with hemangiosarcoma and multiple myeloma.
Hyperestrogenism can be seen with Sertoli cell tumors.
Hyperadrenocorticism is caused by functional adrenal or pituitary tumors.
A 2-year old male castrated Bull Mastiff with a history of travel in the west coast presents to your clinic for a chronic cough and a recent development of lameness of his right hind limb. On physical exam you notice a draining lesion over the lame region of the right hind limb. You perform chest radiographs and see a diffuse bronchointerstitial pattern which is nodular in some regions. You also identify hilar lymphadenopathy. You suspect that you know what you are dealing with and perform a broncho-alveolar lavage for cytology. Just as you suspected, you see spherules.
What is your diagnosis?
- Aspergillosis
- Cryptococcus
- Histoplasmosis
- Coccidioidomycosis
- Blastomycosis
Answer: Cccidioidomycosis
Explanation
The correct answer is Coccidioidomycosis. The travel history and clinical signs are consistent with this answer.
Additionally, finding spherules on cytology is pathognomonic for Coccidioidomycosis. Prolonged antifungal treatment will be necessary. Fluconazole is the treatment of choice. Ketoconazole and itraconazole are good choices. With blastomycosis you see broad based budding of the yeast. With Cryptococcus neoformans you will see narrow-based budding.
A 5 year old male intact dog is brought into your clinic by his owner who states that he bit a neighbor child in the face yesterday. He wants the dog immediately euthanized and wants to bury the dog on his ranch property. He said he had all his shots as a puppy. What is the best course of action?
- Have the owner sign a euthanasia form and euthanize the dog; because this is an owned pet and not a stray, quarantine is not required.
- Collect a blood sample from the dog to submit to the laboratory for rabies testing prior to euthanasia.
- Have the owner sign the euthanasia form and euthanize the dog, but keep the body in case the dog needs to be tested for rabies.
- Notify your local public health authority and quarantine for 10 days.
Answer Notify your local public health authority and quarantine for 10 days.
Explanation
Potential rabies exposure constitutes a significant public health concern. Because we know this animal bit someone, it is important to ascertain what the state law is where you practice.
Per the CDC and the 2016 Rabies Guidelines:
If a healthy animal, regardless of rabies vaccination status bites a human, it should be quarantined for 10 days.
Do not vaccinate. Report to local health department sign of illness. Euthanize and submit for testing if symptoms develop that are suggestive of rabies.
***PowerPage: Rabies
What is the most common tumor of the oral cavity in the dog, as seen in the photo?
- Melanoma
- Lymphoma
- Fibrosarcoma
- Acanthomatous epulis
Answer: Melanoma
Explanation
The correct answer is melanoma. Melanoma comprises about 1/3 of all oral tumors in dogs. Many oral melanomas may be amelanotic, as the one in the photograph appears to be. The second most common tumor is squamous cell carcinoma followed by fibrosarcoma and acanthomatous epulis.
***PowerPage: Oral Melanoma
***PowerLecture: Oral Tumors
How would you evaluate whether or not the mandibular branch of cranial nerve V (trigeminal nerve) is functionally intact in a dog?
- Look for symmetry and tone of the muscles of mastication
- Trigeminofacial reflex
- Deviation of the nose to one side
- Drooping of the upper lip on one side
Answer: Look for symmetry and tone of the muscles of mastication
Explanation
The correct answer is look for symmetry and tone of the muscles of mastication. The mandibular branch of CN V carries sensory and motor function to the muscles of mastication. If the mandibular branch was not functional, there would initially be decreased tone in the muscles of mastication. After a long period of time, contracture of the muscles would cause an increased tone. The trigeminofacial reflex tests the maxillary branch of CN V (sensory afferent) and CN VII (facial nerve). Deviation of the nose to one side occurs with facial nerve paralysis. The nose deviates away from the lesion when the problem is acute due to lack of muscle tone on that side. The nose deviates toward the side of the lesion when the problem is chronic due to contracture of the muscles on the affected side. Drooping of the upper lip on one side would also be due to a lesion of the facial nerve.
How would you evaluate whether or not the mandibular branch of cranial nerve V (trigeminal nerve) is functionally intact in a dog?
- Look for symmetry and tone of the muscles of mastication
- Trigeminofacial reflex
- Deviation of the nose to one side
- Drooping of the upper lip on one side
Answer: Look for symmetry and tone of the muscles of mastication
Explanation
The correct answer is look for symmetry and tone of the muscles of mastication. The mandibular branch of CN V carries sensory and motor function to the muscles of mastication. If the mandibular branch was not functional, there would initially be decreased tone in the muscles of mastication. After a long period of time, contracture of the muscles would cause an increased tone. The trigeminofacial reflex tests the maxillary branch of CN V (sensory afferent) and CN VII (facial nerve). Deviation of the nose to one side occurs with facial nerve paralysis. The nose deviates away from the lesion when the problem is acute due to lack of muscle tone on that side. The nose deviates toward the side of the lesion when the problem is chronic due to contracture of the muscles on the affected side. Drooping of the upper lip on one side would also be due to a lesion of the facial nerve.
A 5-month old male intact Doberman presents for forelimb lameness of 2 days duration. You localize the pain to the carpus on physical exam and take the following radiograph. What is your diagnosis?
- Septic arthritis
- Panosteitis
- Hypertrophic osteopathy
- Hypertrophic osteodystrophy
Answer: Hypertrophic osteodystrophy
Explanation
The radiograph shows the classic signs of hypertrophic osteodystrophy. There is a double physeal line in the metaphysis and areas of bony proliferation. The metaphyses are flared as well.
Panosteitis has a patchy trabecular pattern.
Hypertrophic osteopathy is a disease of older animals generally associated with metastatic disease. The main radiographic finding is periosteal reaction around the metacarpals, tarsals and digits. More than one limb is usually affected and if seen, further diagnostics to look for a primary site of neoplasia is warranted.
Soft tissue swelling and joint effusion are seen with septic arthritis and bony changes can be seen with chronic disease.
You are seeing a dog that you suspect has iatrogenic Cushing’s disease from high-dose prednisone administration. What would you expect on blood samples submitted for ACTH and cortisol levels submitted to a commercial lab?
- ACTH high, cortisol high
- ACTH low, cortisol high
- ACTH low, cortisol low
- ACTH high, cortisol low
Answer: ACTH low, cortisol high
Explanation
The correct answer is ACTH low, cortisol high.
Prednisone is a synthetic corticosteroid that cross reacts with assays measuring endogenous cortisollevels, Causing an artficialy elevated cortisol measurement on blood tests. The feedback mechanism on the pituitary gland inhibits ACTH production, making it low.
Which is a reasonable plan for the treatment of bacterial pneumonia in a dog?
- Systemic antibiotics, bronchodilators, corticosteroids, oxygen therapy
- Systemic antibiotics, cough suppressants, coupage, oxygen therapy
- Oxygen therapy, diuretics, bronchodilators, and systemic antibiotics
- Coupage, systemic antibiotics, oxygen therapy, and nebulization
Answer: Coupage, systemic antibiotics, oxygen therapy, and nebulization
Explanation
The correct answer is coupage, systemic antibiotics, oxygen therapy, and nebulization. All of the choices include systemic antibiotics and oxygen therapy, which are absolutely indicated. Coupage and nebulization are also helpful adjuncts. Coupage may mechanically jar secretions and stimulate cough and can be performed for 5-10 minutes several times daily. Nebulization is to maintain airway hydration. It is not always necessary but is appropriate. Cough suppressants are contraindicated as are corticosteroids since they both interfere with normal defenses. Diuretics are contraindicated as well as they decrease airway hydration.
Bronchodilators are controversial but are not a mainstay of therapy for pneumonia unless bronchoconstriction is present.
Attached are x-rays of a 4-year old 63 pound German Shepherd mix. She presented yesterday with toe touching mixed with non-weight bearing continuing for the past 5 days. She was therapeutically started on Tramadol, Previcox and acepromazine as this pet is very active and hard to keep still. On the basis of the signalment and radiographic findings. What clinical exam finding would you expect to find and on which limb?
- This patient is expected to have bone pain on palpation of the distal femur on the right hind limb
- This patient is expected to have cranial drawer on the left hind limb
- This patient is expected to have tibial thrust on the right hind limb
- This patient is expected to have patellar luxation of the left hind limb
Answer: This patient is expected to have cranial drawer on the left hind limb
Explanation
Based on the radiographic finding of marked stifle effusion of the left stifle noted by the displacement of the infrapatellar fat pad (cloudy area as compared to right stifle) this patient likely has a cranial cruciate ligament rupture. The history and signalment help you to arrive at this top differential.
Other differentials such as immune mediated polyarthritis or joint infection would be ruled out after a thorough orthopedic exam. During this exam one can expect to find tibial thrust, cranial drawer, and pain on extension of the stifle.
Cranial cruciate ligament injuries are the most common orthopedic problem seen in dogs and should be a high differential for any large breed, active dog, with an acute history of lameness. Patellar luxation is relatively uncommon in large breed dogs and would be a very low differential. The right stifle radiograph has no effusion associated with the joint but does show some boney changes that are likely incidental, perhaps from prior trauma, at the distal aspect of the patella.
A 6-year old Schipperke presents with a 1-month history of progressive weakness and decreased appetite. The owner reports the dog is slightly polyuric and polydipsic. Your physical exam is unremarkable except that the dog seems subdued and a bit uncomfortable. You perform bloodwork which shows the following results:
Hematocrit - 28% (Normal 36%-50%)
White Blood Cell Count - 16,000/ul (Normal 7,000-17,000/ul)
Thrombocytes - 324,000/ul (Normal 200,000-900,000/ul)
Calcium - 13.2 mg/dl (Normal 8-11 mg/dl)
Phosphorus - 2.9 mg/dl (Normal 2.4-4.9 mg/dl)
Total Bilirubin - 0.1 mg/dl (Normal 0.06-0.61 mg/dl)
Total Protein - 7.2 g/dl (Normal 5.5-7.3 g/dl)
Albumin - 2.3 g/dl (Normal 2.2-4.2 g/dl)
Globulins - 4.9 g/dl (Normal 2.6-4.5 g/dl)
Alkaline Phosphatase - 45 IU/l (Normal 10-80 IU/l)
Aspartate Aminotransferase - 8 IU/l (Normal 0-20 IU/l)
Alanine Aminotransferase - 17 IU/l (Normal 3-33 IU/l)
Gamma-Glutamyl Transferase - 2 IU/l (Normal 1.3-12 IU/l)
Blood Urea Nitrogen - 17 mg/dl (Normal 10-22 mg/dl)
Creatinine - 1.4 mg/dl (Normal 0.5-2.2 mg/dl)
Glucose - 96 mg/dl (Normal 60-125 mg/dl)
Cholesterol - 180 mg/dl (Normal 125-250 mg/dl)
You perform whole-body radiographs which are shown below. Which of the following choices are two tests that will help you confirm the most likely diagnosis?
- Echocardiogram, heartworm antigen test
- Urinalysis, renal biopsy
- Bone marrow biopsy, serum electrophoresis
- Ultrasound of neck, measure serum parathyroid hormone
- ACTH stimulation test, dexamethasone suppression test
Answer: Bone marrow biopsy, serum electrophoresis
Explanation
This dog has signs and bloodwork findings that are consistent with but not specific for multiple myeloma. The hypercalcemia and hyperglobulinemia are both mild and are consistent with this diagnosis but would not be sufficient alone to jump to that conclusion. The key finding in these case is the radiographic evidence of multiple punctate lucencies including in the body of L4, several of the thoracic dorsal spinous processes, the left ilium, and the right and left humeral diaphyses. These lesions are strongly suggestive of multiple myeloma; however, definitive diagnosis of multiple myeloma requires satisfying at least two of the following criteria:
- Monoclonal gammopathy
- Radiographic evidence of osteolytic bone lesions (satisfied in this case)
- > 5% neoplastic cells or >10-20% plasma cells in the bone marrow
- Immunoglobulin light chain proteinuria (Bence-Jones proteinuria)
Therefore, the best answer in this question is to perform serum electrophoresis to assess monoclonal gammopathy and a bone marrow biopsy to look for neoplastic infiltration of plasma cells.
Annotations:
Yellow circles: Some of the multifocal lytic lesions affecting the vertebrae and pevlis have been circled.
Zinc toxicity from ingestion of pennies minted after 1983 can cause which of the following?
- Hemolysis
- Muscle spasms
- Thrombocytopenia
- Coagulopathy
Answer: Hemolysis
Explanation
The correct answer is hemolysis. Zinc causes a Heinz body anemia and hemolysis.
You have just diagnosed your first case of nephrogenic diabetes insipidus, with a little help from the internist in your practice. The owner would like to discuss treatment options. Which of the following is a treatment option for primary nephrogenic diabetes insipidus in a dog?
- Hydrochlorothiazide
- Salting the food
- DDAVP
- Insulin
Answer: Hydrochlorothiazide
Explanation
The correct answer is hydrochlorothiazide. Hydrochlorothiazide is a thiazide diuretic that paradoxically reduces urine output in patients with diabetes insipidus. Hydrochlorothiazide and AVOIDING excess salt intake are palliative measures that reduce urine output by reducing plasma sodium concentration, which reduces stimulation to the thirst center and water intake. This leads to a reduction in extracellular fluid volume and a decreased glomerular filtration rate.
DDAVP is a synthetic antidiuretic hormone (ADH) used for treating central diabetes insipidus. With nephrogenic diabetes insipidus, there is an adequate amount of ADH, but the ADH receptors in the kidneys do not function properly. Diabetes mellitus requires insulin because it causes elevated blood sugar levels. Nephrogenic diabetes is due to a problem in the kidneys, and is not treated with insulin.
You suspect Coccidioidomycosis in your canine patient. Demonstration of which of these in a sample from a bronchoalveolar lavage would confirm your suspicions?
- Small yeast with a very large clear capsule
- Broad-based budding yeast
- Small round intracellular yeast
- Spherule
- Branching fungal hyphae
Answer: Spherule
Explanation
The correct answer is spherule. The diagnostic stage of Coccidioides immitis is the spherule. This is a 20-200 micrometer round, double-walled structure containing many endospores. As a reminder, the broad-based budding yeast is Blastomyces. The small yeast with large capsule is Cryptococcus, and the branching fungal hypha is Aspergillus. The small intracellular yeast is Histoplasma.
A 1-year-old female Golden Retriever “Stella” presents with bilateral exophthalmos that has taken place over the past 2 days. T= 102.2, HR 140, RR 30. Lab work is unremarkable. She does not seem painful, and no swelling around the eyes is evident. Pupillary light response is normal in both eyes and there is minimal resistance to retropulsion of the globes. The masticatory muscles do not appear to be affected and there is no difficulty opening the mouth. Stella is apparently healthy other than the exophthalmos. What condition do you suspect?
- Orbital neoplasia
- Extraocular polymyositis
- Lymphoma
- Retrobulbar abscess
Answer: Extraocular polymyositis
Explanation
The answer is extraocular polymyositis. Extraocular polymyositis is a condition seen primarily in young Goldens and they present with the signs above. It is kind of similar to masticatory muscle myositis in that it occurs due to an autoimmune reaction against muscle antigens. It is treated with prednisone +/- azathioprine. The condition can be differentiated from these other conditions because orbital neoplasia and retrobulbar abscesses are usually unilateral. Abscesses are usually accompanied by more systemic signs. Orbital neoplasia is usually more slowly progressive and seen in older animals. Lymphoma could present in a similar fashion but is less likely in such a young dog with no other signs.
A 4 year old female spayed German Shorthaired Pointer presents with the complaint of exercise intolerance and lethargy. Thoracic radiographs are taken and are shown below. What therapy is appropriate for the most likely diagnosis?
- Enalapril
- Sucralfate
- Inhaled fluticasone
- Pyridostigmine
- Rimadyl
Answer: Pyridostigmine
Explanation
The correct answer is pyridostigmine. The important thing to do in this case is to both read the question carefully and view the radiograph in concert with each other. This dog has signs and findings that are most consistent with myasthenia gravis and resultant megaesophagus. Accordingly, pyridostigmine, which is an acetylcholinesterase inhibitor (anticholinesterase), is the best answer choice. If you chose sucralfate because you saw the megaesophagus and thought the dog must have esophagitis, your thinking was accurate but you ignored the dog’s clinical signs of weakness. If this dog had presented for regurgitation, that would have been a more appropriate course of action. Acquired myasthenia gravis can also be treated with systemic corticosteroids to decrease immune attack of acetylcholine receptors, but inhaled fluticasone would not do the trick. Enalapril and NSAIDs are not indicated in this patient.
Annotations:
Orange lines: Outline of the gas dilated esophagus
Yellow circles: Areas of alveolar pattern consistent with aspiration pneumonia.
Radiographs provided by Adrien Hespel, DVM, MS, DACVR and University of Tennessee College of Veterinary Medicine
What type of urinary stone is likely to form in an animal being treated with too much allopurinol?
- Struvite
- Calcium oxalate
- Xanthine
- Cysteine
- Urate
Answer: Xanthine
Explanation
The correct answer is xanthine stones. Allopurinol is used in the treatment of urate stone forming Dalmatians. It acts by inhibiting the enzyme, xanthine oxidase, which metabolizes xanthine. The idea is that by stopping the purine metabolism pathway at this point, uric acid will not be formed in high quantities. However, if given at too high of a dose, xanthine will accumulate to levels where xanthine stones will form.
A 2-year-old Collie bitch presents for estrus evaluation. The owner reports that about 4 days ago, she noticed vulvar swelling and there has been mild to moderate hemorrhagic vaginal discharge. The bitch has not been exposed to males yet to assess her receptivity. You perform vaginal cytology and a representative field is shown below. What should you tell the owner?
- The dog appears to be in proestrus
- The dog appears to be metestrus
- The dog appears to be in diestrus
- The dog appears to be in estrus
- The dog appears to be anestrus
Answer: The dog appears to be in proestrus
Explanation
The timing of the dog’s clinical presentation and vaginal cytology findings are most consistent with proestrus.
Proestrus is characterized by <90% cornified cells. The cytology here is predominantly parabasal and intermediate cells; it is common for early proestrus to be characterized by these cells and gradually transition until nearly 100% of the cells are cornified by estrus. It is also common to see bloody vaginal discharge and very few or no red blood cells on the vaginal smear.
***PowerLecture: Estrous Cycle Part 1
An 8 year old, 5kg, female spayed West Highland Terrier has presented to your hospital with a history of right hind limb lameness. Previously she had a left extracapsular repair performed on her left stifle. The owners note that she was playing with their new dog and then yelped and has now been limping without major improvement for the past 3 weeks. She is also Addisonian. She receives an injection every 28 days (owners can’t remember medication name) and she is also on 1.25 mg of prednisone once per day. On examination there is tibial thrust and cranial drawer elicited on the right hind limb. The owners have consented to surgical repair this afternoon. What is the best method of dealing with her Addison’s disease given that she is going to have surgery?
- Give a dose of flucortisone (Florinef) prior to surgery and monitor electrolytes perioperatively
- Give a dose of dexamethasone SP that is equivalent to 1mg/kg of prednisone prior to surgery followed by a dose of dexamethasone SP that is equivalent to 0.5mg/kg of prednisone the following day
- Beginning the day of surgery wean the patient off of prednisone until the patient is two weeks out from surgery
- Give a dose of dexamethasone SP that is approximately 5 times the physiologic dose of prednisone before surgery followed by twice the regular dose of prednisone the following day
Answer: Give a dose of dexamethasone SP that is approximately 5 times the physiologic dose of prednisone before surgery followed by twice the regular dose of prednisone the following day
Explanation
Patients with Addison’s disease have hypoadrenocorticism. This means that the patient is not producing an adequate amount of glucocorticoids. During times of stress Addisonian patients require additional amounts of glucocorticoids or else they are at risk of going into a crisis. The exact amount of additional glucocorticoid to administer is not known but it is generally accepted that patients should receive 2-10 times a physiologic dose of prednisone. The physiologic dose of prednisone is considered by many to be 0.1 mg/kg/day but there is some variation depending on the source. Therefore the best answer is to give a dose of dexamethasone that is approximately 5 times the physiologic dose of prednisone followed by twice the regular dose of prednisone the following day.
The patient is likely receiving deoxycorticosterone pivalate (Percorten) which is given at approximately 25-28 day intervals and is a means of providing the necessary mineralocorticoids. An alternative treatment for mineralocorticoid replacement is fludrocortisone acetate (Florinef).
This medication needs to be administered daily.
Weaning the patient off of prednisone is contraindicated and will result in an Addisonian crisis as the patient is unable to produce its own cortisol.
What is the prognosis for a dog with spinal trauma that has no deep pain for greater than 24 hours?
- Guarded with surgical repair of the lesion
- Guarded with strict cage rest and high dose corticosteroid treatment
- Good with surgical repair of the lesion
- Fair with strict cage rest and high dose corticosteroid treatment
- Poor with surgical repair of the lesion
Answer: Poor with surgical repair of the lesion
Explanation
The correct answer is poor. The lack of deep pain with spinal cord trauma is a poor prognostic indicator, and even with surgical intervention at this point, there is less than a 5% chance of a return to function.
A 7-year-old mixed breed dog presents for re-evaluation of demodicosis and severe flea allergic dermatitis. The dog’s skin is doing much better since being on Ivermectin, and you plan to continue treatment. The owner is very concerned about the area around the tail base, as the patient has been extremely pruritic in that region. You suspect flea allergy dermatitis and ask the owner if she is still using flea medications. The owner explains that she stopped the flea medication when Ivermectin was started. You ask about the other animals in the household, and the owner replies that the rabbit and cat have no clinical signs. The owner also states that the cat and rabbit continue to sleep with the dog despite his skin condition. Which flea medication would be a good choice for this patient?
- Atoxalaner
- Spinosad
- Permethrin
- Lufenuron
- Pyriproxyfen
Answer: Atoxalaner
Explanation
From the list of medications Afoxalaner (Nexgard) is the best choice. This flea medication contains an adulticide; whereas, pyriproxyfen and Lufenuron are only insect growth regulators. Spinosad should never be used with extra-label doses of Ivermectin and is probably why this client discontinued flea medications in the first place.
Permethin is an excellent flea medication, as it is a repellent and adulticide, but it is toxic to cats. Fipronil is toxic to rabbits.
***PowerPage: Flea Allergy Dermatitis
A 1-year-old male neutered Chihuahua presents for a 3 month history of intermittent limping and non-weight bearing on the left hind limb. On physical exam, it is difficult to determine the source of pain as the patient seems to try to bite on any manipulation of the left hind limb. The patient was sedated and these radiographs were obtained. What is your diagnosis and treatment?
- Left hip dysplasia. Perform femoral head and neck ostectomy or total hip replacement
- Left hip septic arthritis. Perform joint culture and begin appropriate antibiotic therapy
- Avascular necrosis of the femoral head. Perform femoral head and neck ostectomy or total hip replacement
- Left patellar luxation. Perform trochlear wedge recession with tibial tuberosity transposition
Answer: Avascular necrosis of the femoral head. Perform femoral head and neck ostectomy or total hip replacement
Explanation
Based on the breed and age of the patient, avascular necrosis of the femoral head should immediately be the top differential. This condition is also known as Legg-Calves-Perthes disease and results in a collapse or fragmentation of the femoral epiphysis (as seen on the radiographs) because of a disruption in blood flow. The cause of blood flow interruption is unknown. The condition occurs in young small-breed dogs prior to closure of the capital femoral physis. The condition can be seen bilaterally in 10-17% of patients. Dogs are usually 6-7 months of age when they first start showing clinical signs but the age may range from 3-13 months. Treatment with a femoral head and neck ostectomy (FHO) generally yields excellent results. Alternatively, if owners demand perfect biomechanics, a total hip replacement may be considered, but most veterinarians tend to recommend an FHO.
Radiographs will typically show a shortening of the femoral neck as well as osteochondrosis with chronicity, as appreciated in this patient. Note the significant muscle atrophy of the patient’s left limb as compared to the right. Patellar luxation should always be a differential in any small breed dog and this should be ruled out via palpation since the patient may not necessarily be luxated at the time the radiograph was taken. The patient’s patellas are in a normal position in this radiograph.
Septic arthritis of the femoral head is an uncommon condition which is more often seen in large-breed dogs with a history of degenerative joint disease of the hips. They present with acute lameness, severe hip pain, and are usually febrile. Radiographs usually show degenerative joint disease along with potentially lytic areas associated with the femoral head. Neoplasia should also be considered in these cases.
Small-breed dogs are less likely to have hip dysplasia as compared to large-breed dogs and should be kept as a lower differential.
Radiographs provided by Adrien Hespel, DVM, MS, DACVR and University of Tennessee College of Veterinary Medicine
You perform a routine fecal flotation on a 1-year old Fox Terrier at a wellness examination and find the eggs shown in the image below (image taken at 40X, scale not shown but organisms are approximately 70 um). Select the answer which appropriately shows the clinical signs that would be expected in dogs infested with the organism and in humans that acquire zoonotic infection from dogs.
- Dogs: Anemia
Humans: Cutaneous larval migrans - Dogs: Liver failure
Humans: Visceral larva migrans - Dogs: Diarrhea
Humans: Anemia - Dogs: Diarrhea
Humans: Ocular larva migrans - Dogs: Diarrhea
Humans: Liver failure - Dogs: Cutaneous larva migrans
Humans: Anemia
Answer: Dogs: Anemia / Humans: Cutaneous larval migrans
Explanation
This is a case of hookworms (Ancylostoma caninum). The eggs are recognizable by their thin-walled appearance with 2-8 cells that are passed.
Hookworms penetrate through the skin in young pups and migrate to the lungs where they are coughed up and swallowed and mature in the small intestine. There, the worms suck blood and cause bleeding ulcers; up to 0.1 ml of blood per worm can be lost per day.
Aberrant migration under the skin of infected people results in cutaneous larva migrans.
Visceral and ocular larva migrans in people are usually due to Toxocara (roundworms).
A 4-year old male castrated Basenji presents for polyuria, polydipsia, and weight loss. Blood work shows P=2.5 (2.9-5.3 mg/dl), K= 3.1 (3.9-5.1 mEq/L), total CO2= 12 (17-25 mmol/L). The remainder of the blood work is within normal limits. Urinalysis shows 3+ glucose. Which of the following is your most likely differential diagnosis?
- Pyelonephritis
- Diabetes mellitus
- Pyometra
- Fanconi syndrome
Answer: Fanconi syndrome
Explanation
The correct answer is Fanconi syndrome. Fanconi syndrome is an inherited disease in Basenjis. The disease involves renal tubular defects causing an abnormal loss of electrolytes and solutes leading to hypophosphatemia, hypokalemia, and metabolic acidosis. DM is less likely because serum glucose is normal.
The lab abnormalities present in this dog are not consistent with pyelonephritis. Pyometra is not a viable choice as the signalment describes a male.
A 7-year old female spayed Cocker Spaniel presents for an inflamed and buphthalmic left eye. She has a history of bilateral cataracts but can still see relatively well. Intraocular pressures were taken and the left eye was found to be high, while the right eye was within normal limits. What is the most likely cause for the increased intraocular pressure in the left eye?
- A retrobulbar mass
- Increased production of aqueous due to inflammation
- Sequela of the cataracts
- Inherited glaucoma
Answer: Inherited glaucoma
Explanation
The correct answer is inherited glaucoma. Cocker Spaniels are predisposed to developing eye problems such as cataracts, distichiasis, retinal abnormalities, and primary glaucoma.
Even though only the left eye currently has increased intraocular pressures, the right eye should be treated as well because it will likely develop glaucoma in the future.
A 9 year old female spayed mixed breed dog presents for regurgitation of food after meals and exercise intolerance. Thoracic radiographs showed megaesophagus. What is the treatment for the most likely disease that the dog is presenting for?
- Fluoroquinolone antibiotics, nebulization, and coupage
- Calcium gluconate
- L-asparaginase and prednisone
- Cholinesterase inhibitors
Answer: Cholinesterase inhibitors
Explanation
The correct answer is cholinesterase inhibitors. The dog has Myasthenia Gravis, which is caused by antibody-mediated destruction of acetylcholine receptors. Cholinesterase inhibitors decrease the break down of acetylcholine, making more acetylcholine available to bind to the remaining acetylcholine receptors.
Myasthenia Gravis can be caused by immune mediated disease (related to hypothyroidism), paraneoplastic syndrome (associated with thymoma), and can be familial in certain breeds (Newfoundland and Great Dane).
Which of the following is not typically a cause of chronic renal failure in small animals?
- Polycystic kidney disease
- Amyloidosis
- Leptospirosis
- Familial nephropathy
Answer: Leptospirosis
Explanation
The correct answer is leptospirosis. Leptospirosis typically manifests as acute renal failure.
A 2-year old female spayed mixed breed dog presents in acute oliguric renal failure. The dog has a history of drinking ethylene glycol two days ago. What step should be taken next?
- Start treating the dog with activated charcoal orally and tell the owner the dog has a guarded prognosis.
- Start treating the dog with ethanol IV and give a guarded to poor prognosis to the owner.
- Start treating the dog with 4-Methylpyrazole IV and give a guarded to poor prognosis to the owner.
- Tell the owner the dog has a guarded to poor prognosis and may need hemodialysis
Answer: Tell the owner the dog has a guarded to poor prognosis and may need hemodialysis
Explanation
The correct answer is tell the owner the dog has a guarded to poor prognosis and may need hemodialysis.
4-MP and ethanol act by preventing alcohol dehydrogenase from converting ethylene glycol to its toxic metabolites.
In animals where oliguric renal failure has already begun, most of the ethylene glycol will already have been metabolized, so there is no benefit to giving ethanol or 4-MP. Activated charcoal should only be given if the ethylene glycol was ingested within 2 hours.
***PowerPage: Toxins in the Garage (ethylene glycol, household cleaners)
You are examining the eyes of a dog with all the signs of Horner’s syndrome. After instilling topical hydroxyamphetamine, there is no change. You then instill topical phenylephrine and in 5 minutes, the eye returns to normal. What can you conclude about this dog’s Horner’s?
- He has a pre-ganglionic lesion
- The Horner’s has only been present for less than 24 hours
- He has a post-ganglionic lesion
- The Horner’s is idiopathic in origin
- The Horner’s has been present for a long time
Answer: He has a post-ganglionic lesion
Explanation
The answer is that he has a post-ganglionic lesion. Hydroxyamphetamine acts by encouraging release of norepinephrine (NE) from the postsynaptic neuron. If there is a pre-ganglionic lesion, NE will still be released by the postsynaptic neuron and signs will resolve. If there is a post-ganglionic lesion, there will be no NE to release.
Also, with a post-ganglionic lesion, denervation hypersensitivity to NE occurs. As a result, adding phenylephrine topically can cause a rapid response. With pre-ganglionic lesions, the response usually takes greater than 20 minutes.
A 4-year old Dachshund presents for biting and chewing the nails of all four paws. The owner explains that the behavior started this summer, but the patient seems to be generally itchy every summer since he was one year old. Please refer to the picture for the physical examination findings. Based on the history and physical examination, which of the following is your most likely diagnosis?
- Trauma
- Malassezia infection
- Neoplasia
- Symmetrical lupoid onychodystrophy
- Sarcoptes scabiei
Answer: Malassezia infection
Explanation
Malassezia infection of the claws often produces a red-brown discoloration. Other clues that this is more likely Malassezia include biting at the nails (sign of pruritus), multiple claws are infected, and the dog has other symptoms of allergy (pruritus in summer months), which could be this patient’s underlying disease. Trauma and neoplasia are less likely since multiple claws are infected, and these typically are not pruritic unless there is a secondary bacterial component. Symmetrical lupoid onychodystrophy results in severe splitting and deformation of the nails. Sarcoptes does not discolor the nails.
A 4-year old female Brittany Spaniel presents for further evaluation of suspected dystocia. Her gestation length is approximately 60 days and the owners note that she has been extremely restless, panting, and vomited once in the past 8 hours. On vaginal examination, there is no obviously obstructed puppy. Radiographs of the dog show no evidence of fetal gas or alteration in spatial relationship between the fetal bones. What is the best treatment for this dog?
- Perform a Caesarian section
- Continue to monitor carefully without disturbing her and have the dog return in 24 hours if she has not delivered the puppies
- Administer intramuscular dexamethasone sodium phosphate
- Administer intramuscular oxytocin
Answer: Continue to monitor carefully without disturbing her and have the dog return in 24 hours if she has not delivered the puppies
Explanation
Based on the history and clinical examination findings, this dog has presented in stage 1 of labor.
This stage is typically 6-12 hours of length and can persist for up to 36 hours. In this stage, it is expected for the dog to exhibit panting, trembling, nesting behavior, and restlessness. Occasionally dogs will also vomit. At this point, there is sub-clinical uterine contraction and dilation of the cervix. Stage 2 will also last approximately 6-12 hours (and persist up to 36hr) and is characterized by abdominal straining which coincides with uterine contraction. Puppy delivery occurs during Stage 2 at an interval of 30-60min (up to 4 hours).
Stage 3 involves the expulsion of fetal membranes as well as involution of the uterus. Fetal membranes are usually passed 5-15 minutes after birth of a pup before another puppy can be delivered from the same horn.
Thick greenish discharge (lochia) is seen in all stages of labor and may persist for up to three weeks. Complete uterine involution and endometrial recovery occurs in approximately 3 months.
In an animal with pleural effusion, which radiographic view will give you the best view of the heart?
- Dorsoventral
- Left lateral
- Right lateral
- Ventrodorsal
Answer: Ventrodorsal
Explanation
The correct answer is ventrodorsal. Pleural effusion obscures the heart completely on a dorsoventral radiograph and at least partially on lateral radiographs. Ventrodorsal positioning usually moves the pleural fluid away from the heart and allows for a radiographic view of the heart to be obtained. Of course, in dyspneic animals, it may not be wise to position them ventrodorsally.
A 3-year old male castrated Labrador Retriever presents for severe hemorrhagic enteritis, lethargy, and anorexia. The dog has a history of going fishing with the owner about one week before the onset of the clinical signs. The physical exam reveals generalized
lymphadenopathy. Which of the following is the most likely etiologic agent causing these clinical signs?
- Paragonimus kellicotti
- Nanophyetus salmincola
- Neorickettsia helminthoeca
- Salmonid fish
Answer: Neorickettsia helminthoeca
Explanation
The correct answer is Neorickettsia helminthoeca.
This dog most likely has salmon poisoning disease.
The etiologic agent of the disease is the rickettsia, Neorickettsia helminthoeca, which is vectored by the intestinal fluke, Nanophyetus salmincola. Dogs get the disease by eating salmonid fish infected with the cercaria of the fluke, which harbor the rickettsia. Clinical signs along with finding fluke eggs in the feces of the dog is usually enough to make the diagnosis. Paragonimus kellicotti is a lung fluke of the dog.
Administration of which of the following would not adversely affect the results of an ACTH stimulation test?
- Dexamethasone
- Prednisone
- Prednisolone
- Cortisone
- Flucortisone acetate
Answer: Dexamethasone
Explanation
The correct answer is dexamethasone.
Administration of dexamethasone or desoxycorticosterone acetate (DOCA) prior to
ACTH stimulation test does not confound the test results. Administration of prednisone, cortisone, prednisolone, and flucortisone acetate would show false elevations in test results.
A 10 year-old male neutered German Shepherd presents for a slowly progressive weakness in the hind limbs. He has conscious proprioception deficits in both rear limbs, and the dorsal nail surfaces are worn. His front limbs are normal, the hind limbs are hyper-reflexive, and he is able to hold his urine and feces until let outside. Based on the breed and clinical signs, what is your most likely diagnosis?
- Degenerative myelopathy
- Intervertebral disc disease in C7-2 spinal segment
- Fibrocartilaginous embolism
- Lyme disease
- Hip dysplasia
Answer: Degenerative myelopathy
Explanation
According to this patient’s clinical signs there is a lesion from T3-L3, evidenced by the upper motor neuron signs in the hind limbs and no clinical signs in the front limbs. Because of the progressive nature of the disease, you can rule out a fibrocartilaginous embolism. Hip dysplasia can be difficult to differentiate from degenerative myelopathy in some patients, but the reflexes should not be affected with degenerative joint disease. Lyme disease would likely be acutely painful and/or recurrent in nature.
You are seeing a dog that you suspect has iatrogenic Cushing’s disease from high-dose prednisone administration. What would you expect on blood samples submitted for ACTH and cortisol levels submitted to a commercial lab?
- ACTH high, cortisol high
- ACTH high, cortisol low
- ACTH low, cortisol low
- ACTH low, cortisol high
Answer: ACTH low, cortisol high
Explanation
The correct answer is ACTH low, cortisol high. Prednisone is a synthetic corticosteroid that cross reacts with assays measuring endogenous cortisol levels, causing an artificially elevated cortisol measurement on blood tests. The feedback mechanism on the pituitary gland inhibits ACTH production, making it low.
A 4-year old female spayed mixed breed dog presents for dysuria. Urinalysis shows a pH of 9.0 and numerous cocci and crystals in the sediment. The dog is otherwise normal and healthy. Which crystal type is most likely present?
- Struvite
- Cysteine
- Calcium oxalate
- Urate
Answer: Struvita
Explanation
The correct answer is struvite. Struvite or magnesium ammonium phosphate crystals form in alkaline urine, whereas most other crystal types form in acidic urine. The cocci present are urease positive bacteria that cleave urea to ammonia causing the urine pH to rise and making the environment more favorable for struvite crystals to form. Cysteine crystals form as a result of a genetic defect of the renal tubules, and are almost exclusively seen only in males. Urate crystals only form in Dalmatians (due to a genetic defect in urate metabolism) and animals with portosystemic shunts or liver dysfunction. Urates are less likely in this patient, since it is not a Dalmatian and shows no signs of liver disease.
What is the method of choice for diagnosing rabies?
- Gross pathologic lesions
- Direct fluorescent antibody test
- Immunohistochemistry
- Visualization of Negri bodies
- RT-PCR
Answer: Direct fluorescent antibody test
Explanation
The correct answer is direct fluorescent antibody test. There are no gross pathologic lesions associated with rabies. A diagnostic microscopic lesion is the visualization of Negri bodies. Most commonly they occur in the hippocampus in carnivores and Purkinje cells in herbivores. However, these are only seen 50% of the time.
Immunohistochemistry allows strain differentiation and the ability to differentiate vaccine vs. wild-type. RT-PCR has been used on autolyzed brain tissue that is difficult to evaluate with fluorescent antibodies, but this is not the test of choice at this time. Direct FA is the current preferred method of diagnosis; it is both rapid and sensitive. Usually impressions of the medulla, cerebellum, and hippocampus are performed.
Which of the following medications used for urinary incontinence in dogs is a weak alpha agonist?
- Phenylpropanolamine
- Propranolol
- Diethylstilbesterol
- Testosterone
Answer: Phenylpropanolamine
Explanation
The correct answer is phenylpropanolamine. This medication increases urethral sphincter tone and helps prevent incontinence. Diethylstilbesterol and testosterone have been used for incontinence, but both are hormones. Propranolol is a beta blocker used for certain types of heart disease.
Which of the following medications used for urinary incontinence in dogs is a weak alpha agonist?
- Phenylpropanolamine
- Propranolol
- Diethylstilbesterol
- Testosterone
Answer: Phenylpropanolamine
Explanation
The correct answer is phenylpropanolamine. This medication increases urethral sphincter tone and helps prevent incontinence. Diethylstilbesterol and testosterone have been used for incontinence, but both are hormones. Propranolol is a beta blocker used for certain types of heart disease.
A 3-year old male castrated Akita presents for a femoral fracture. Which fracture repair method is not an option?
- Typell external fixator
- Type I external fixator
- Intramedullary pin with cerclage wires
- Bone plate
Answer: Typell external fixator
Explanation
The correct answer is Type Il external fixator. A type I external fixator can be placed from the lateral aspect of the femur, but the medial aspect of the femur can not be approached for a type ll external fixator due to the bone being directly adjacent to the trunk of the animal.
Which of these is not a proper treatment for glaucoma (primary or secondary) in a dog?
- IV mannitol
- Oral methazolamide (carbonic anhydrase inhibitor)
- Topical latanoprost (prostaglandin analog)
- Topical mannitol
- Topical dorzolamide (carbonic anhydrase inhibitor)
Answer: Topical mannitol
Explanation
The answer is topical mannitol. Carbonic anhydrase inhibitors act by decreasing aqueous production which is partially dependent on the conversion of carbon dioxide to bicarbonate. It can be used topically or systemically.
Latanoprost (Xalatan) is a prostaglandin analog frequently used topically in the treatment of glaucoma. IV mannitol works to decrease IOP through its properties as an osmotic attractant. It is not used topically.
A 6-year old male castrated Dachshund presented for further evaluation after an acute onset of a “drunken gait”. On physical examination, hind limb ataxia is confirmed as well as decreased motor on both hind limbs (worse on the right), conscious proprioceptive deficits, and hyper-reflexive patellar reflex on the right. The forelimbs appear to be unaffected. Where is the lesion localized?
- C1-C5 myelopathy
- C1-T2 myelopathy
- T11-13 myelopathy
- T3-L3 myelopathy
- L4-S3 myelopathy
Answer: T3-L3 myelopathy
Explanation
This signalment and clinical signs are consistent with interverebral disc disease (disc herniation).
Dachshunds are the most common breed to develop IVDD. The clinical signs described in this case are not complete but do give you enough information to determine that upper motor neuron signs are present (hyper-reflexive). This immediately eliminates the possibility of having a caudal spinal cord injury as those result in lower motor neuron signs (hypo-reflexia). Deficits of the forelimbs are usually associated with neck lesions. A Schiff-Sherington posture is one exception in which the forelimbs are affected but the lesion is not in the neck.
Although it is very common for lesions to be between T11-13 such a specific location is not defined by the neurologic exam findings provided. The neurological exam description is not very specific and the localization is T3-L3.
Which of the following clinical signs may be seen with discoid lupus erythematosus (DLE) in dogs?
- Symmetrical truncal alopecia
- Hyperpigmentation of the ventral abdomen
- Swollen, painful joints
- Depigmentation of the nasal planum
Answer: Depigmentation of the nasal planum
Explanation
The correct answer is depigmentation of the nasal planum. Clinical signs consistent with DLE include depigmentation, erythema, scaling, and loss of the “cobblestone” appearance of the nasal planum. Alopecia, crusting, scaling, and ulcerations can also be seen on the face, muzzle, lips, pinnae, and periorbitally.
Truncal alopecia would be more common with endocrine disease, such as hypothyroidism or Cushing’s disease.
Discoid lupus is the cutaneous form, and the joints are not affected like they are with systemic lupus erythematosus (SLE).
Which of the following clinical signs may be seen with discoid lupus erythematosus (DLE) in dogs?
- Symmetrical truncal alopecia
- Hyperpigmentation of the ventral abdomen
- Swollen, painful joints
- Depigmentation of the nasal planum
Answer: Depigmentation of the nasal planum
Explanation
The correct answer is depigmentation of the nasal planum. Clinical signs consistent with DLE include depigmentation, erythema, scaling, and loss of the “cobblestone” appearance of the nasal planum. Alopecia, crusting, scaling, and ulcerations can also be seen on the face, muzzle, lips, pinnae, and periorbitally.
Truncal alopecia would be more common with endocrine disease, such as hypothyroidism or Cushing’s disease.
Discoid lupus is the cutaneous form, and the joints are not affected like they are with systemic lupus erythematosus (SLE).
You are assisting the ophthalmologist with an eye exam during your internship rotation and examining a 5-year-old German Shepherd who has recently been lethargic and seems to be having difficulty seeing, especially at night. On dilated fundic examination, you note gray areas in the fundus, and the retina appears blurry. You also note a small area of hemorrhage in the left eye. You help perform an electroretinogram (ERG) which showed impaired cone function. Eye tests are as follows:
Fluorescein stain: Negative Tonometry: 8 OS, 12 OD
Schirmer Tear Test: 20mm < 60 sec. OU
Which diagnosis would fit with this dog’s clinical signs and exam?
- Chorioretinitis
- Keratoconjunctivitis sicca
- Optic nerve hypoplasia
- Glaucoma
Answer: Chorioretinitis
Explanation
Chorioretinitis (posterior retinitis) refers to inflammation of the choroid and retina. Signs of ongoing or acute chorioretinitis in dogs are poorly defined gray spots throughout the fundus, retinal separation, and retinal hemorrhage. Active disease, such as in this dog, is typically caused by systemic disease. Full labwork and infectious disease testing should be submitted.
The list of potential causes for chorioretinitis is fairly long:
Parasites
Fungal infections
Bacterial infection (e.g., Rickettsia)
Viral infections (e.g., canine distemper virus, rabies virus, and herpes virus, which is rare and usually seen in newborn puppies)
Algal infections (water plant-based infection, typically from plants growing in stagnant water)
Protozoal infection
Autoimmune disease
Genetic predisposition
Metabolic
Cancer
Generalized infection, such as blood poisoning or bacteria in the blood Toxicity (e.g., antifreeze poisoning, or adverse reaction to medications)
Physical trauma
Idiopathic
Chorioretinitis can lead to glaucoma as a complication, but this dog has below normal intraocular pressures at this time (suggestive of inflammation in the anterior portion of the eye).
Optic nerve hypoplasia is a genetic condition where the optic nerve never fully develops and causes vision loss or blindness. This dog’s tear test is normal, ruling out KCS.
Which statement about hypertrophic osteodystrophy (HOD), as shown in the image below, is true in dogs?
- HOD occurs commonly in small breed dogs
- HOD is unlikely to recur after one episode has resolved
- The treatment of choice for HOD is surgical
- HOD usually occurs in dogs older than 7 years of age
- HOD can be extremely painful, causing lameness in dogs
Answer: HOD can be extremely painful, causing lameness in dogs
Explanation
The correct answer is HOD can be extremely painful, causing lameness in dogs. HOD usually occurs in young, large breed dogs. It can recur after an episode resolves, and treatment usually involves analgesia and supportive care. Surgery is not a treatment option.
Radiographically, this condition appears as a line of lucency where the bone has been destroyed, typically parallel to the growth plates of the affected bones. This is sometimes referred to as a “double physis” sign.
A 1-year old female spayed Doberman Pinscher has presented after being hit by a car. Initial chest radiographs show mild contusions, and the patient appears to be otherwise stable. A right mid-shaft long oblique femoral fracture has been identified. Routine pre-operative blood work is unremarkable. A buccal mucosal bleeding test (BMBT) is elevated at 6 minutes. What will you administer prior to surgery?
- Desmopressin acetate
- 1,25 dihydrocholecalciferol
- Whole blood transfusion
- Vitamin K
Answer: Desmopressin acetate
Explanation
The correct answer is desmopressin acetate (DDAVP). Administration of desmopressin results in release of von Willebrand factor, which will help this patient with clotting. Given this dog’s breed and elevated BMBT there is a very strong likelihood she is afflicted with von Willebrand’s disease. In Dobermans this results in an inability to form a clot. This can be life threatening if the dog is taken to surgery.
A whole blood transfusion does not provide an adequate source of von Willebrand factor but may be necessary if the patient’s bleeding cannot be controlled despite appropriate pre-operative measures. 1,25 dihydrocholecalciferol is the active form of vitamin D which aids intestinal resorption of calcium.
The BMBT does not assess factors 2, 7, 9, or 10 and therefore vitamin K is not indicated.
A dog presents to your clinic for coughing and fever a week after going hunting. You work the dog up, perform bronchoscopy and remove a plant awn from the lungs. What bacterial infection is this dog predisposed to?
- Staphylococcus pseudointermedius
- Actinomyces
- Nocardia
- Staphylococcus aureus
- Pasteurella multocida
Answer: Actinomyces
Explanation
The correct answer is Actinomyces. This is a filamentous, branching, gram positive bacteria that is a normal inhabitant of the mouth and oropharynx. It is commonly associated with grass awn migration. These are usually contaminated in the oropharynx and then migrate through the body from the respiratory or GI tracts. Many times it takes months to years to make a diagnosis. Nocardia is a ubiquitous soil saprophyte found everywhere and is usually introduced via the respiratory tract.
Which of the fungal infections is considered contagious, either to other animals or to man (zoonotic)?
- Cryptococcosis
- Aspergillosis
- Blastomycosis
- Sporotrichosis
- Coccidioidomycosis
Answer: Sporotrichosis
Explanation
The correct answer is Sporotrichosis. All of these fungal diseases can infect both animals and people. However, they are not considered contagious (not to be confused with infectious) with the exception of Sporothrix. This is because they are mainly acquired from the environment, and transmission from animal to animal is rare.
Sporothrix, especially in cats, is a high risk to veterinarians and care should be taken to limit contact with exudates and lesions in cats.
Aspergillus is generally considered a ubiquitous fungus that causes infection due to host factors such as immunosucceptibility or certain breed predilections. Cryptococcus is also not a contagious disease (do NOT confuse this with cryptosporidium, which is very contagious and zoonotic as several of my colleagues can attest to profusely). Cryptococcus infection occurs from inhalation of the yeast from the environment, frequently avian habitats, as it survives ideally in pigeon droppings. Essentially, histoplasma, blastomyces, and Coccidioides are also all environmental diseases as well and not considered contagious.
Incidentally, there is a true story of a pathologist who did acquire Coccidioides from an animal that was having a necropsy. It is likely that the fungus reverted to the mycelial phase and produced infectious arthroconidia at the low temperatures achieved in the dead animal. This is also a risk when changing bandages for the same reason.
These fungi are also potentially infectious when they are being grown on culture plates. So even though they are not technically contagious (at least in terms of how the board examiners view them), there are still risks.
What is the approximate resting energy requirement for a 25 kg dog?
- 500 kcal/day
- 800 kcal/day
- 2100 kcal/day
- 1400 kcal/day
Answer: 800 kcal/day
Explanation
The correct answer is 800 kcal/day. There are many formulas for calculating RER and they all should work out to be pretty close to this. The formula used here is body weight (kg) to the 0.75 power times 70. (70 * BW^0.75).
Another formula that has been recommended for this calculation is (30 * BW + 70). Note that the results will be different compared to the (70 * BW^0.75) formula but they both should get you close enough to the correct answer.
You will have access to an “on screen” calculator during the exam if necessary, but may want to remember multiple ways to do a calculation should there not be access to a “power” (^) function.
ChatGPT:
The approximate resting energy requirement (RER) for a 25 kg dog can be calculated using the formula:

Alternatively, a commonly used simplified formula is:

For a 25 kg dog:

Thus, the correct answer is 800 kcal/day.
A 9-year old female spayed Chihuahua presents to you with the skin abnormality shown below. She has similar lesions all over the rest of her body. A superficial and deep skin scraping show many moving “cigar shaped” mites. Which of these products is the only FDA approved for treatment of this disease?
- Lime Sulfur
- Amitraz (Mitaban)
- Chlorhexadine
- Milbemycin (Interceptor)
- Ivermectin (Ivomec)
Answer: Amitraz (Mitaban)
Explanation
The correct answer is amitraz (Mitaban). This is a case of generalized demodicosis which can occur in older dogs as well as young dogs. It is caused by the commensal mite, Demodex canis, and is often secondary to an underlying disease or immunosuppression. There are several treatment options (and you should probably know them all) but the only FDA-approved treatment is Amitraz (Mitaban). Ivermectin and milbemycin are also used to treat this condition in part because it is difficult to obtain Mitaban. Mitaban is used as dip and should be administered in a hospital, which is time consuming when there are other treatment options that can be similarly effective although used “off-label”. Mitaban should be used cautiously in animals with skin lesions since more systemic absorption of Mitaban will occur which increases the likelihood of toxic affects.
A 10-year-old male Pomeranian presents to you with a 3-month history of wheezing and marked respiratory distress. The owner reports that he has been coughing sporadically as if trying to clear his throat of a hairball. The owner is a regular smoker. On your examination, the dog displays moderate expiratory difficulty. You submit blood work and take radiographs including inspiratory and expiratory lateral projections of the dog, which are shown below. Which of the following are commonly used to treat the likely condition?
- Surgical repair of the defect
- Butorphanol and theophylline
- Meloxicam and fluconazole
- Amoxicillin, nebulization, and coupage
- Furosemide and prednisone
Answer: Butorphanol and theophylline
Explanation
The radiographs show dynamic collapse of the intrathoracic trachea, carina, and mainstem bronchi. There is a marked redundant tracheal membrane in the cervical region. The left atrium may be slightly enlarged but there is no evidence of left heart failure. Based on these findings, you should suspect that tracheal collapse is the cause of the dog’s clinical signs.
Treatment options include bronchodilators (i.e. theophylline, terbutaline), cough suppressants (hydrocodone, butorphanol), weight loss, and corticosteroids to control inflammation. In severely affected dogs, sedation may be necessary to break the cough cycle. Dogs should be kept away from smoke and environmental pollution.
About 70% of dogs respond to medical management. Those that don’t are sometimes treated with stents or tracheal rings, but neither repairs the underlying cartilaginous defect.
Furosemide is not an appropriate treatment as there is no evidence of heart failure. Nebulization and coupage are used to treat pneumonia, which is also not present in this case.
Annotations:
Red is the tracheal diameter, much more narrowed on the Right lat
Green is a redundant tracheal membrane visible on the left lateral
Yellow are primary bronchi for the right cranial lung lobe (left lateral), and cranial subsegment of the left cranial lung lobe (right lateral). Notice the large difference in diameter. Tracheomalacia, bronchomalacia and redundant tracheal membrane.
Blue: there is significant narrowing of the tracheal bifurcation on the right lateral compared to left. Indicative of dynamic airway collapse.
Radiographs provided by Adrien Hespel, DVM, MS, DACVR and University of Tennessee College of Veterinary Medicine
A 12-year-old mixed breed female spayed dog presents with a several-month history of lethargy, hair loss, and greasy skin. The patient’s face, feet, and tail are not clinically affected and she is mildly pruritic. This photomicrograph shows the results of impression cytology obtained from the patient. What is the most likely name of the organism pictured?
- Staphylococcus hyicus
- Malassezia pachydermatis
- Staphylococcus pseudintermedius (Staphylococcus intermedius)
- Malassezia globosa
Answer: Staphylococcus pseudintermedius (Staphylococcus intermedius)
Explanation
Intracytoplasmic cocci from a dog’s skin are most likely Staphylococcus pseudintermedius (formerly called Staphylococcus intermedius), which is the species host-adapted to canines. Staphylococcus hyicus is host-adapted to pigs, so is less likely to be isolated from a dog. Malassezia (yeast) organisms are much larger than cocci and are not observed within the cytoplasm of neutrophils.
You perform thoracocentesis on a dog with pleural effusion. The fluid is an opaque pink color and has a protein content of 2.5 g/dl. There are 3,000 cells/uL. You suspect that it is chyle. What is the test of choice to definitively classify this fluid?
- Triglyceride concentration of the fluid compared to serum
- Culture and sensitivity of the fluid
- Thoracic radiographs
- Glucose concentration of the fluid compared
to serum - Differential cell count on the fluid
Answer: Triglyceride concentration of the fluid compared to serum
Explanation
The correct answer is triglyceride concentration of the fluid compared to serum. The fluid described is most consistent with a chylous effusion. The best way to definitively classify chyle is finding an elevated triglyceride level compared to serum. If you chose differential cell count, this is also a good answer because most chylous effusions are composed primarily of lymphocytes, unlike other effusions. However, with prolonged loss of lymphocytes, chronic chylous effusions may be composed primarily of neutrophils, which may lead you to believe it is an exudate. Radiographs and culture and sensitivity may be appropriate tests but will not help you classify the fluid.
Glucose concentration of the fluid is not useful in this instance. It is sometimes used to diagnose pyothorax as glucose concentrations are typically <
10 mg/dl.
An 11-year old male castrated Border Collie presents in lateral recumbency. The owners noticed he had been limping on his right front leg for the past three days. He has free access to the backyard, but did not come back to the house this morning for breakfast and the owners found him outside laterally recumbent. On physical exam, he has extensor rigidity of all four legs with extension of his head and neck (as seen in the image). His lips and ears are contracted and pulled back. There is a wound between digits 2 and 3 on the right forelimb with a draining tract. Which of the following should be discussed with the owner?
- Tetanus antitoxin can cause anaphylaxis.
- Removal of the tick will help reverse clinical signs.
- Tetanus antitoxin will help to reverse the clinical signs.
- Confirmatory diagnosis involves finding the exotoxin from Clostidium botulinum in serum, feces, vomit, or food samples.
Answer: Tetanus antitoxin can cause anaphylaxis.
Explanation
The facial contraction and smirk is a characteristic sign of tetanus. Tetanus is caused by the neurotoxin produced by Clostridium tetani. This bacteria enters the body through a wound and begins producing tetanospasmin, a potent neurotoxin that blocks GABA release at the motor end plate and causes sustained muscle contraction.
Treatment involves wound debridement, sedation, antibiotics, and minimizing external stimuli as these animals are hyperesthetic. Tetanus antitoxin is given after an initial test dose to monitor for anaphylaxis. Antitoxin prevents further toxin binding but does not affect already bound toxin so it helps decrease progression of clinical signs but will not reverse the signs present.
Tick paralysis starts with hind limb weakness which progresses to a stiff forelimb gait and flaccid paralysis.
Patients will improve quickly after removal of the tick. Clostridium botulinum causes botulism which is characterized by lower motor neuron paresis/paralysis starting in the pelvic limbs and progressing to quadriplegia. There is decreased muscle tone in all limbs.
What is the most appropriate medical treatment for transitional cell carcinoma at the trigone of the bladder, as depicted in the photo?
- Piroxicam and carboplatin chemotherapy
- Clavamox and furosemide
- Prednisone and vinblastine or lomustine chemotherapy
- Prednisone and combination chemotherapy with cyclophosphamide, vincristine, and doxorubicin
- Carprofen and combination chemotherapy with cyclophosphamide, vincristine, and doxorubicin
Answer: Piroxicam and carboplatin chemotherapy
Explanation
Transitional cell carcinoma of the bladder in dogs can be palliatively managed with non-steroidal anti-inflammatory drugs such as piroxicam. Progression-free interval and survival can be extended with the addition of chemotherapy. The most commonly used agents are carboplatin, cisplatin, and mitoxantrone. Although cisplatin is effective against TCC, it has increased nephrotoxicity with piroxicam and is less commonly used these days in the author’s experience. Secondary infections can be treated with appropriate antibiotics.
This dog has been on chronic steroid therapy and has now developed this lesion seen in the photograph. Biopsy results of the skin show a broad based budding organism. What is your diagnosis?
- Coccidioidomycosis
- Cryptococcosis
- Blastomycosis
- Aspergillosis
Answer: Blastomycosis
Explanation
The correct answer is blastomycosis. Finding a broad-based budding organism is specific to blastomycosis. This dog is likely to have a travel history to the Ohio River valley. Being on chronic steroids resulted in
immunosuppression and acquiring subsequent infection.
A 10-year old female German Shepherd presents to you with a mass on the 3rd digit of the left hind foot that has been present for 3 weeks and growing. On physical exam, the mass is dark red and the skin is hairless. You perform a fine needle aspirate and evaluate it cytologically. A representative field from the aspirate is shown in the image below. What is the most likely diagnosis?
- Fibrosarcoma
- Mast cell tumor
- Lymphoma
- Squamous cell carcinoma
- Melanoma
Answer: Melanoma
Explanation
The cytology shows cells with large nuclei, stippled chromatin with prominent and sometimes multiple nucleoli (labeled with 1). A few cells (labeled with a 2) have dark green/black melanin granules.
Melanoma is an important differential for a nail bed tumor. At this site, they are frequently malignant and the local lymph node should be palpated and aspirated. Additional staging (thoracic radiographs and abdominal ultrasound) should also be considered. If there is no evidence of metastasis, the affected digit should be amputated.
You are a practicing veterinarian in sunny California when a 5-year old female spayed Doberman arrives at your clinic with anorexia, lethargy, depression, and weight loss. On physical exam you notice several nodular and draining skin lesions. There is lymphadenopathy, and you detect a cough. Further examination reveals uveitis. You question the owner and he mentions that he and his dog are originally from the Ohio River valley. You perform cytology on fine needle aspirates that you obtained from the skin nodules and enlarged lymph nodes. What organism do you expect to find?
- Cryptococcus neoformans
- Histoplasma capsulatum
- Blastomyces dermatitidis
- Sporothrix schencki
- Streptococcus
Answer: Blastomyces dermatitidis
Explanation
The correct answer is Blastomyces dermatitidis. You can come to this diagnosis by thinking about the clinical findings and travel history, which are both characteristic for blastomycosis. On cytology you can expect to see a 5-20 micrometer diameter thick, refractile, double-contoured cell wall, and broad-based budding organism. Transmission is a result of spores inhaled from the environment which form yeast in the lungs and then disseminate through the blood and lymphatics. Itraconazole is usually the drug of choice for uncomplicated disease.
Histoplasmosis usually occurs in the Ohio, Mississippi, and Missouri river valleys, but skin and ocular lesions occur uncommonly. Usually, you will see Gl involvement, especially large bowel.
Usually, with histoplasmosis you will see large numbers of small round bodies with a basophilic center in mononuclear phagovtes from vour sample.
You are examining the eyes of a 4-year old German Shepherd. You see corneal melanosis and vascularization along the lateral aspect of the limbus. Both eyes show similar lesions. A Schirmer tear test is normal, and fluorescein dye is negative for stain uptake. What is the most likely diagnosis?
- Keratoconjunctivitis sicca
- Trauma
- Ocular lymphoma
- Chronic superficial keratitis
Answer: Chronic superficial keratitis
Explanation
The answer is chronic superficial keratitis, sometimes referred to as pannus. It is a condition seen mainly in German Shepherd and shepherd crosses and is due to UV light exposure. It is believed that the UV light alters corneal proteins leading to an immune reaction. It is treated with topical steroids and cyclosporine, and animals often require lifelong therapy. KCS is not the correct choice because of the normal tear test. Lymphoma in the eye should cause changes in the uvea or retina but rarely the cornea.
This patient is having a gastric resection performed as a result of gastric necrosis. The patient had gastric dilatation and volvulus (GDV). Which of the following gastropexy techniques can result in an inadvertent incision into the stomach if the animal requires surgery later in life?
- Endoscopically-assisted gastropexy
- Belt Loop gastropexy
- Incisional gastropexy
- Incorporating gastropexy
- Circumcostal gastropexy
Answer: Incorporating gastropexy
Explanation
The correct answer is incorporating gastropexy. This technique is easy and rapid to perform. It involves making an incision through the seromuscular layer of the stomach and then suturing it to the linea alba as you are closing your incision. As a result, if one ever goes back into the abdomen, there is a risk of cutting into the stomach since it will be adhered to the linea alba. For this reason, some surgeons will advise against this procedure. A circumcostal gastropexy involves wrapping a section of the seromuscular layer of the stomach around a rib and then suturing it back onto the stomach. An incisional gastropexy involves making an incision onto the abdominal wall and the seromuscular layer of the stomach, and then suturing them together so the stomach ends up sutured up against the body wall. A belt loop gastropexy involves making two parallel incisions into the abdominal wall musculature and then passing a section of seromuscular layer of the stomach through one incision, out the other, and then suturing it back onto the stomach. An endoscopically-assisted gastropexy is a method of performing a fast and relatively easy prophylactic gastropexy.
A 5-year old male neutered Pembroke Welsh Corgi presents to you with a complaint of mild lethargy and reluctance to play for about one week’s duration. On your exam, the dog is quiet but alert and responsive. T-102.3 F (39.1 C), HR-112 bpm, RR-24 bpm. You note decreased weight bearing on the left pelvic limb and swelling of the stifle. You elect to perform radiographs of the left stifle which confirm the presence of effusion but no significant bony changes are appreciated. A complete blood count and biochemistry show the following:
Hematocrit -38% (Normal 36%-50%)
White Blood Cell Count - 12,500/ul (Normal 7,000-17,000/ul)
Thrombocytes - 322,000/ul (Normal 200,000-900,000/ul)
Calcium - 10.2 mg/dl (Normal 8-11 mg/dl)
Phosphorus - 3.2 mg/dl (Normal 2.4-4.9 mg/dl)
Total Protein - 6.8 g/dl (Normal 5.5-7.3 g/dl)
Alkaline Phosphatase -33 IU/ (Normal 10-80 IU/l)
Alanine Aminotransferase - 14 IU/I (Normal 3-33 IU/l)
Blood Urea Nitrogen - 32 mg/dl (Normal 10-22 mg/d)
Creatinine - 1.4 mg/dl (Normal 0.5-2.2 mg/dl)
Glucose - 95 md/gl (Normal 60-125 mg/dl)
You sedate the dog to perform arthrocentesis of the left stifle and withdraw 1.0 ml of cloudy fluid. You view the fluid cytologically and a representative field is shown in the image below. What additional diagnostic test is most important?
- Culture of the fluid
- Arthroscopy
- Echocardiogram
- Urinalysis
- Total protein of the fluid
Explanation
This is a description of septic arthritis based primarily on the cytologic findings of neutrophils and bacteria in the joint fluid cytology. Note that the bacteria are within the neutrophils (intracellular bacteria) which assures that this is not contamination on your slide. There is no other likely explanation for such a finding. The dog’s clinical presentation of nonspecific signs and mild lameness or decreased weight bearing is consistent with this diagnosis. There may be a history of trauma to the affected joint that allowed for entry of bacteria, but such an instance is not always identified. The bloodwork is within normal limits. Occasionally, systemic signs of inflammation or infection may be present with septic arthritis but if the infection is contained within the joint, it is common for bloodwork to be unremarkable.
All of the answer choices might be reasonable recommendations but the most important diagnostic test is to culture the joint fluid to determine the etiologic agent and its antibiotic susceptibility as this will most directly impact your choice of therapy. The treatment of choice for septic arthritis is a prolonged (at least one month) course of an appropriate antibiotic. In some cases, drainage/lavage of the joint or surgery may be necessary.
Total protein of the joint fluid can be helpful to classify it and monitor changes with treatment.
Urinalysis or echocardiogram might be indicated if you were suspicious that the septic joint was the result of hematogenous spread of bacteria from another site such as a subclinical urinary tract infection or valvular endocarditis. Arthroscopy might be useful to better examine and to flush the joint.
The image below is from an aspirate taken through the soft palate from a mass in the nose of an 8-year old male neutered Rhodesian Ridgeback dog. Choose the correct cell type of origin AND classification.
- Mesenchymal origin; sarcoma
- Mesenchymal origin; round cell tumor
- Mesenchymal origin; carcinoma
- Epithelial origin; carcinoma
- Epithelial origin; sarcoma
- Leukocyte origin; round cell tumor
Answer: Epithelial origin; carcinoma
Explanation
This is a nasal adenocarcinoma. The classification scheme for tumors by cell of origin and cytologic description is:
Carcinoma- These tumors come from epithelial cells including cells of glandular tissues such as salivary glands, mammary glands, and cells lining most tissues including squamous cells or transitional cells. The cytologic appearance is that of COHESIVE CLUSTERS of cells. Here, you can see some of the tight cellular junctions in the cluster which is typical. Cells are often polygonal in shape.
Sarcoma- These tumors come from mesenchymal cells and are named by the specific cell type such as fibroblasts (fibrosarcoma) and osteoblasts (osteosarcoma). Cytologically, they tend to appear as isolated spindle-shaped cells with elongated cytoplasm and often oval nuclei.
Round cell tumors- There are 5 round cell tumors and most but not all come from blood cells. They are lymphoma, mast cell tumors, plasma cell tumors, histiocytic tumors, and transmissible venereal tumors.
Remember, these are also sometimes also referred to as sarcomas (i.e. lymphosarcoma or histiocytic sarcoma).
Cytologically, they appear usually as large populations of cells that are not in defined clusters. The cells have a round shape, often with unique identifiable features such as the purple granules in mast cell tumors.
***PowerLecture: Nasal Tumors
Which of the following is the best way to find Giardia canis trophozoites?
- Direct fecal smear
- Baermann technique
- Fecal flotation
- Fecal sedimentation
Answer: Direct fecal smear
Explanation
Giardia trophozoites and cysts are typically found on a direct fecal smear. Giardia cysts can be found on fecal flotation also. The organism can also be detected by FA and ELISA.
The Baermann technique is a method of recovering larvae from fecal material and is most commonly used when looking for nematode parasites, most often lungworm.
Here is an image of a Giardia trophozoite:
A 12-year old English Bulldog presents with anorexia and severe, generalized pain. What is the best description of the lesions in this radiograph?
- Polyostotic, non-aggressive
- Monostotic, non-aggressive
- Polyostotic, aggressive
- Monostotic, aggressive
Answer: Polyostotic, aggressive
Explanation
There are multiple lytic lesions in the cervical and thoracic vertebrae, especially visible in C2 and in the spinous processes of the T1-T8. There are also lytic lesions in the proximal humerus of one leg and in the bones of the skull.
A 2-year old female spayed Spaniel-cross presents to you with sneezing and ocular discharge. On examination, the dog appears systemically healthy with normal vital parameters. You are suspicious of a viral upper respiratory tract infection with possible secondary bacterial infection and prescribe a 2-week course of cephalexin. 10 days later, the dog returns to your clinic with a fever and severe cutaneous ulcerations as shown in the image which the owner says began just 3 days ago. Skin biopsy confirms coagulative necrosis of the epidermis with mixed inflammation in the dermis and epidermis. Which of the following should you tell the owner?
- You are most concerned about development of a drug-resistant and aggressive form of Streptococcus and the dog should be quarantined with additional antibiotics prescribed pending cultures
- You are most concerned that the dog actually had an aspergillus infection which was not susceptible to cephalexin and she now has systemic aspergillosis; the dog should be hospitalized and started on antifungals
- You are most concerned that the dog actually had nasal lymphoma originally which has now disseminated systemically including to the skin; she should be fully staged and treated for lymphoma
- You are most concerned about a severe and potentially life-threatening cutaneous drug reaction and the dog should be hospitalized for supportive care and testing
Answer: You are most concerned about a severe and potentially life-threatening cutaneous drug reaction and the dog should be hospitalized for supportive care and testing
Explanation
The history and clinical appearance are very concerning for toxic epidermal necrolysis which is usually associated with an adverse reaction to a drug. In severe cases such as the dog shown in this image, there is concern for extensive loss of fluids, electrolytes, and colloids as well as secondary bacterial infection of the skin.
Concurrent medications should be withdrawn and aggressive supportive care, analgesia, and use of a different antibiotic protocol are indicated. The prognosis is guarded depending on response to removal of a suspected inciting cause.
The other possibilities listed in this question are less consistent with the cutaneous lesions shown and the very rapid onset and progression as well as the histopathologic findings.
A 5 year old, male neutered, West Highland White Terrier presents for the skin lesions seen in the picture below. He has a history of lethargy and poor appetite. The lesions partially responded to antibiotics initially, but then began to progress again. You take a biopsy of the skin which shows cutaneous blastomycosis. What is the next most important diagnostic test?
- Blastomyces antigen test
- Abdominal radiographs
- Deep skin scraping
- Blastomyces antibody titer
- Thoracic radiographs
Answer: Thoracic radiographs
Explanation
Blastomycosis is caused by a dimorphic fungus and generally occurs in the Missouri, Mississippi, Tennessee, and Ohio river valleys. Pulmonary involvement occurs in the majority of cases, so thoracic radiographs are an important step to staging the patient. Other organs that can be affected include the lymph nodes, eyes, bones, central nervous system, and urinary tract.
Abdominal radiographs are not very sensitive to detect involvement with internal organs. Abdominal ultrasound, if available, would be preferred over abdominal radiographs.
Antibody tests are neither sensitive nor specific and are not very useful once a diagnosis is already made.
A four-year old Labrador Retriever presents with an aural hematoma of the right ear. Given the cytological findings from an ear swab as seen in this image, which one of the following ear cleaning combinations will you not send home with your patient?
- Thiabendazole, neomycin, and dexamethasone
- mometasone, gentamicin, clotrimazole
- Gentamicin, betamethasone valerate, and clotrimazole
- Neomycin, bacitracin, and polymyxin B
Answer: Neomycin, bacitracin, and polymyxin B
Explanation
This patient has a high number of malassezia yeast visualized on cytology. This organism can be responsible for perpetuating otitis externa. It is not unusual to see yeast in the ear canal of a dog; however, yeast numbers of greater than 5 per high powered field can be considered abnormal.
Other clinical signs of otitis externa may include ear pain, pruritis, aural discharge, bad odor, and neurologic
signs.
Effective treatments for uncomplicated otitis externa typically contain an antifungal, antibiotic, and an anti-inflammatory. Since this dog primarily has a yeast infection it is imperative that the ear medication prescribed has an anti-fungal. The answer choices provided are commonly known as triple antibiotic ointment (neomycin, bacitracin, and polymyxin B), Tresaderm (thiabendazole, neomycin, and dexamethasone), Mometamax (mometasone, gentamicin, clotrimazole), and Otomax (gentamicin, betamethasone valerate, and clotrimazole).
Note that the triple antibiotic ointment does not contain an anti-fungal.
Additionally, the ears should be cleaned before applying the ear medication. Many ear cleaners contain antifungals too (Triz Ultra + Ketoconazole), which may enhance treatment response.
Based on the direction of this dog’s head tilt, where would you localize the lesion to if he has a paradoxical vestibular syndrome?
- Left cerebellum
- Left cranial nerve VIII (vestibulocochlear nerve)
- Right cerebellum
- Right cranial nerve VIII (vestibulocochlear nerve)
- Left cerebral hemisphere
Answer: Right cerebellum
Explanation
The correct answer is the right cerebellum. This dog has a left head tilt by definition because his left ear is closer to the ground. The key to answering this question is seeing the left head tilt and reading that the question asks about PARADOXICAL vestibular disease.
Vestibular disease can be peripheral or central, and central vestibular disease can be classic in appearance or paradoxical. Peripheral vestibular disease is due to a lesion in the inner ear or vestibular portion of cranial nerve VIII. Classic central vestibular disease is due to a lesion in the brainstem or cerebellum. Signs with peripheral and classic central vestibular disease include head tilt, falling, and circling to the same side as the lesion with nystagmus with fast phase to the opposite side.
With paradoxical vestibular disease, the lesion is in certain regions of the cerebellum (flocculonodular lobe) or caudal cerebellar peduncle and produces signs to the opposite sides from which is seen with peripheral and classic central disease.
A 4-year-old male castrated Beagle presented with an acute onset of being down in the hind end.
On neurological examination, the patient’s cranial nerves are intact. He has bilateral hind limb conscious proprioceptive deficits and no motor function in either hind limb. There are normo-reflexive gastrocnemius reflexes and normal to hyper-reflexive patellar reflexes bilaterally. The thoracic limbs are neurologically normal. Superficial and deep pain responses are present. A myelogram shows the lesion in the photo below. You discuss treatment options with the owner and she declines surgery. Which of the following is the most important aspect of medical management of the likely condition?
- Exercise and physical therapy
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Muscle relaxants
- If the owner declines surgery, euthanasia is the only humane alternative
- Strict cage rest
Answer: Strict cage rest
Explanation
By far, the most likely diagnosis is intervertebral disc disease (IVDD) based on the history and myelogram showing a collapsed intervertebral space at T12-13 and an extradural compressive lesion originating from the same site. IVDD can be managed by surgical decompression or non-surgically. The most important aspect of non-surgical management of IVDD is STRICT cage rest, usually for a full 8 weeks.
Exercise should be avoided during the period of cage rest. Steroids, analgesics, and/or muscle relaxants may be useful additions to the management of these dogs.
Inguinal hernias occur more commonly in male dogs. They can be congenital or acquired. In order to understand the pathophysiology of these hernias, a clear understanding of anatomy is necessary. This patient sustained a severe inguinal hernia after being hit by a car. Which of the following is NOT a component of the internal inguinal ring?
- Inguinal ligament
- Rectus abdominis
- External abdominal oblique
- Internal abdominal oblique
Answer: External abdominal oblique
Explanation
The external abdominal oblique is a component of the external inguinal ring. All others make up the internal inguinal ring. The rectus abdominis makes up the medial border. The inguinal ligament makes up the lateral and caudal border. Finally, the internal abdominal oblique makes up the cranial border.
Which of the following is a common finding on a complete blood count in a dog with a ruptured splenic hemangiosarcoma?
- Schistocytes
- Eosinophilia
- Neutropenia
- Thrombocytosis
- Heinz body anemia
Answer: Schistocytes
Explanation
Schistocytes are fragmented red blood cells that are mechanically broken up due to the irregular vessels and fibrin strands they pass through in hemangiosarcoma patients. Other typical findings on a CBC in a patient with hemangiosarcoma are thrombocytopenia, anemia (although not with Heinz bodies), and leukocytosis.
An owner brings her 4-year old female Labrador
Retriever to your clinic because she believes she might be pregnant. She does not remember when the dog’s last heat cycle was. The dog’s abdomen appears fairly distended and you take a lateral abdominal radiograph which is shown below. What would be the earliest time you would expect to be able to see fetal skeletons on abdominal radiographs in the dog?
- 43 days gestation
- 53 days gestation
- 23 days gestation
- 33 days gestation
Answer: 43 days gestation
Explanation
The correct answer is 43 days gestation. The fetal skeleton ossifies at 42-45 days in the dog and 35-39 in the cat.
In the dog, a mineralized fetus can usually be seen around 42-46 days. The scapula, humerus, and femur can be made out around 46-51 days.
The ribs can be seen at 52-59 days. Teeth and toes can be seen at 58-63 days.
For the PowerLecture’” on this topic, view
Estrous Cycle Part 3 (5:52)
