Medium Confidence Level NAVLE Questions

Dog with major bleeding needing a blood transfusion. You have several units of blood available from different donors. Which of these are used in the major crossmatch for blood products to be transfused to a dog?

A. Donor red blood cells, recipient plasma

B. Donor red blood cells, donor plasma

C. Recipient red blood cells, donor plasma

D. Recipient red blood cells, recipient plasma

A. Donor red blood cells, recipient plasma

• In a major crossmatch, you are looking to see if the factors in the plasma of the recipient are going to react to the donated red blood cells.

• A minor crossmatch involves recipient red blood cells and donor plasma

A 10 year old female spayed German shepherd dog presents for collapse and difficulty breathing. Your physical exam shows pale mucous membranes, a fluid wave in the abdomen, and a splenic mass. Aspiration of the abdominal fluid shows hemorrhagic effusion that does not clot. Which of the following is commonly found with your presumed diagnosis?

A. Factor VIII deficiency

B. Hypercalcemia

C. Von Willebrand's disease

D. Tumor lysis syndrome

E. Disseminated intravascular coagulation

E. Disseminated intravascular coagulation

• The presumed diagnosis based on the given signalment, physical findings, and diagnostics is splenic hemangiosarcoma, which is often associated with DIC.

Which of these are used in the minor cross match for blood products when looking for a compatible blood donor for a dog?

A. Recipient red blood cells, recipient plasma

B. Recipient red blood cells, donor plasma

C. Donor red blood cells, donor plasma

D. Donor red blood cells, recipient plasma

B. Recipient red blood cells, donor plasma

• In a minor crossmatch, you are looking to see if the factors in the plasma of the donor are going to react to the recipient's red blood cells.

A 10-year old mixed breed dog presents for a 1-month history of anorexia, lethargy, and inappetance. Physical exam reveals pale mucous membranes and a mild tachycardia. The

CBC shows:
MCV 50 fl (66-77 fl)
MCH 12 pg (21-26 pg)
MCHC 25 %g/dl (32-36.3 %g/dl)
HCT 22% (35-57%)
reticulocyte 40,000/ul (<80,000/ul)

What is the most likely diagnosis for this dog?

A. Babesiosis

B. Congenital portosystemic shunt

C. Iron deficiency

D. Anemia of chronic disease

E. Mycoplasma felis infection

C. Iron deficiency

• CBC shows a microcytic, hypochromic, non-regenerative anemia.

• Reticulocyte counts under 60,000/ul are typically considered non-regenerative in most labs. This is consistent with chronic iron deficiency. This most common reason for chronic blood loss is gastrointestinal tract disease such as an ulcer or cancerous lesion.

An adult intact male mixed breed stray dog presents for lethargy and inappetance. The physical exam reveals pale and icteric mucous membranes, and a fever of 103.5F (39.7 C). The dog has a PCV of 22% (35-57%), total protein of 4.9 (5.4-7.5 g/dl). The urinalysis shows hemoglobinuria. A blood smear shows pyriform-shaped structures inside the red blood cells. What is the most likely diagnosis?

A. Babesia infection

B. Acetaminophen toxicity

C. A primary immune-mediated hemolytic anemia

D. A Leukocytozoon infection

E. Ingestion of large amounts of onions

A. Babesia infection

• The pyriform structures in the RBCs reveal the diagnosis. Leukocytozoon only occurs in birds.

A 5-year-old medium sized, spayed female mixed breed dog presents for lethargy, decreased appetite, and shifting leg lameness. On physical exam, you note a mild generalized lymphadenopathy and 103.7°F temperature. On orthopedic exam, no overt lameness is noted when trotted out. However, you detect pain on palpation and manipulation of the right carpus and left hock. Upon questioning the owner further, the dog accompanied the owner on a camping trip a few weeks ago. The owner removed six ticks from the dog. He has also seen tapeworm segments in her bedding since returning. You submit blood and urine for a minimum database as well as additional testing to confirm your suspicions. While you await your results, which antibiotic would be the most appropriate to prescribe?

A. Cefpodoxime

B. Clindamycin

C. Doxycycline

D. Amoxicillin

E. Trimethoprim/sulfamethoxazole

F. Cephalexin

C. Doxycycline

• Dog is most likely suffering from a tick-borne disease. Doxycycline is the treatment of choice for most tick-borne diseases, therefore it would be the most appropriate choice. Since confirmatory titer testing can take up to a few weeks for results, it is appropriate to start empirical therapy while awaiting results.

Von Willebrand's Disease (vWD) is a bleeding disorder in which von Willebrand factor is affected. It may be present in decreased amounts, function abnormally, or not be present at all. A certain breed of dog is highly predisposed to having this disease. It is important to be aware of this condition as surgery in such a patient can result in non-stop bleeding. Which breed is most commonly affected by this condition?

A. Standard Poodle

B. Doberman Pinscher

C. Saint Bernard

D. German Shepherd

E. Flat Coated Retriever

F. Dalmatian

B. Doberman Pinscher

• Dobermans are predisposed to having Type I vWD. In this situation there are decreased amounts of von Willebrand factor present in the blood. This is an autosomal dominant disease. None of the other breeds listed are predisposed to vWD.

A 6-year old male neutered Springer Spaniel presents for lethargy and difficulty walking. The owner reports that over the past week, the dog has become increasingly listless with decreased appetite and seems stiff as though he is "walking on eggs". You examine the dog and find joint pain and effusion bilaterally affecting the carpi, tarsi, stifle, and elbow. The dog also appears uncomfortable on firm spinal palpation. T-103.1 F (39.5 C), HR-118 bpm, RR-30 bpm with intermittent panting. The remainder of your physical exam is within normal limits. You perform a complete blood count and chemistry panel revealing the following:

Hematocrit - 32% (Normal 36%-50%)
White Blood Cell Count - 14,500/ul (Normal 7,000-17,000/ul)
Thrombocytes - 195,000/ul (Normal 200,000-900,000/ul)

Calcium - 10.8 mg/dl (Normal 8-11 mg/dl)
Phosphorus - 2.9 mg/dl (Normal 2.4-4.9 mg/dl)
Total Protein - 6.9 g/dl (Normal 5.5-7.3 g/dl)
Alkaline Phosphatase - 78 IU/l (Normal 10-80 IU/l)
Alanine Aminotransferase - 18 IU/l (Normal 3-33 IU/l)
Blood Urea Nitrogen - 17 mg/dl (Normal 10-22 mg/dl)
Creatinine - 1.1 mg/dl (Normal 0.5-2.2 mg/dl)
Glucose - 91 mg/dl (Normal 60-125 mg/dl)

Urinalysis was within normal limits and urine culture was negative. Radiographs of the affected joints show joint effusion and no bony abnormalities. You perform arthrocentesis of each carpus, the left elbow and right tarsus. You are able to aspirate up to about 0.3ml from each joint; the fluid is thin and turbid; you submit the fluid for analysis. The protein level in the joint fluid ranges from 3.2-3.5 g/dl and the nucleated cell counts are 12,000-18,000 cells/ul consisting primarily of neutrophils, approximately 90% of which are nondegenerate. Smaller numbers of mononuclear cells are present. Culture of the synovial fluid is negative and a panel for tick titers is all negative.

Which of the following treatments is most appropriate based on the presumptive diagnosis?

A. Arthroscopy and amoxicillin

B. Enalapril and furosemide

C. Prednisone and azathioprine

D. Plasma transfusion and intravenous fluids

E. Doxycycline and enrofloxacin

C. Prednisone and azathioprine

• IMPA is often classified as being erosive or nonerosive. This case is an example of the nonerosive form based on the lack of radiographic evidence of cartilage or subchondral bone destruction. The erosive form is rare and is thought to account for <1% of the cases of IMPA.

• Nonerosive IMPA can be associated w/ systemic infectious, inflammatory, or neoplastic dz or rxns to drugs or vax but it is most commonly idiopathic with no association to another disease process. In the described case, no risk factors or signs of concurrent disease were mentioned. Tick-borne arthropathy is less likely with the negative tick titers obtained, but since not every type of tick can be tested for, some clinicians may opt to treat with an antibiotic like doxycycline concurrently with the immunosuppressive drugs.

• IMPA CS: anorexia, weight loss, fever, lethargy, and lymphadenopathy. Up to 25% of dogs present with only nonspecific signs of systemic illness and without apparent gait abnormality or joint effusion. It is an important consideration for dogs with fever of unknown origin and may be the cause up to 20% of the time. IMPA is diagnosed by synovial fluid analysis although additional baseline diagnostics are indicated to screen for potential systemic or infectious causes. Normal synovial fluid is clear and viscous with <2.5 g/dl protein and <3,000 cells/ul with predominantly mononuclear cells. Joint fluid in IMPA may be thin, turbid, and increased in volume with higher amounts of protein and cells, often primarily nondegenerate neutrophils.

• Tx of idiopathic IMPA centers on immunosuppressive therapy, often starting with prednisone and sometimes including an additional immunosuppressive drug such as azathioprine or cyclophosphamide. About 80% of dogs will respond to immunosuppressive doses of prednisone; however, about one half of dogs require long-term or additional drug therapy to maintain remission.

Which of the following is a common finding on a complete blood count in a dog with a ruptured splenic hemangiosarcoma?

A. Schistocytes

B. Thrombocytosis

C. Neutropenia

D. Eosinophilia

E. Heinz body anemia

A. Schistocytes

• 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.

What stimulates antidiuretic hormone (ADH) secretion in the horse?

A. Hyperosmolality and decreased circulating blood volume

B. Hypoosmolality and decreased circulating volume

C. Hyperosmolality and increased circulating blood volume

D. Hypoosmolality and increased circulating volume

A. Hyperosmolality and decreased circulating blood volume

• In the horse, as in other species, ADH increases renal water reabsorption and urine osmolality by increasing permeability of the collecting tubules. Osmoreceptors in the hypothalamus detect subtle changes in plasma osmolality. If osmolality rises, you will hope to see ADH secretion so that the urine excreted would be more concentrated. The same is true if circulating volume decreases; thus, a lesser volume of water would be lost. When ADH secretion does not occur or if the kidneys are unable to respond to ADH, this is likely diabetes insipidus, and animals will be very polyuric, polydipsic and have extremely dilute urine.

In June, you are asked to examine an 8 year old horse which has been out in a California pasture for over a month. The horse is thin and mildly depressed. There is a tremor of the lips and tongue, and when feed is offered, the lips are pulled back indicating marked dystonia of the facial muscles. The horse is unable to prehend the feed. Which of the following causes should you look for to match these clinical signs?

A. Sarcocystis

B. Lead

C. Yellow star thistle

D. Aberrant strongyle migration

E. Ethylene glycol

C. Yellow star thistle

• Yellow star thistle is Centaurea solstitialis. In some horses which ingest large quantities, it can cause nigropallidal encephalomalacia, which is loss of the globus pallidus and substantia nigra, and extrapyramidal nuclei, which control muscles of prehension. Loss of these nuclei causes tremors and dystonia of the lip muscles and tongue. Centaurea repens (Russian knapweed) can also cause similar lesions.

Which of these recommendations is appropriate for a horse that has chronic obstructive pulmonary disease?

A. Feed a pelleted ration rather than hay

B. Treat with broad spectrum antibiotics

C. Maintain the horse in a stable whenever possible

D. Treat daily with atropine

A. Feed a pelleted ration rather than hay

• Environmental factors and dust are thought to play a major role in the pathogenesis of COPD. An alternative to feeding pellets is to soak hay prior to feeding to reduce the dust taken in when eating. Stabled horses are much more likely to develop signs. Atropine can be given to bronchodilate in emergencies for acute attacks but should not be given routinely, as it can predispose to development of colic. Antibiotics would not be an effective recommendation because the disease is not infectious (there is no bacterial component to treat in most cases).