Flashcards in VETPREP Deck (153)
What does cyanosis generally indicate?
Hypoxemia -PaO2 of < 50 mm Hg
This 2 year-old female spayed Siamese cat presents for further evaluation of the masses seen in the image. The patient was recently rescued and there is no other history available. On physical examination, there are no overt abnormalities appreciated other than the masses visualized. A fine needle aspirate is performed and consistent with a mast cell tumor. Given the breed, the histiocytic subtype is suspected. Which of the following is the most appropriate treatment plan if the owners don't have unlimited funds?
Monitor as the lesions will most likely spontaneously regress
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?
- Cocker Spaniels are predisposed to developing eye problems such as cataracts, distichiasis, retinal abnormalities, and primary glaucoma.
Which of the following tests used to test a population of cats will yield the most false negatives?
Sensitivity 65%, Specificity 95%
The sensitivity determines the number of false negatives because sensitivity looks at the animals that do have the disease of interest and is the percentage of them that will test positive. If 65% test positive, that means 65% are true positive and 35% are false negative. Specificity defines the number of true negatives and false positives.
You are examining a flock of chickens that has recently had a 10-20% drop in egg production. You note that chickens are displaying signs of varying severity including watery eyes, nasal discharge, dyspnea with extension of the neck during inspiration, coughing of mucus and blood, and decreased food intake. There has been low mortality from this condition and you perform a necropsy on a deceased chicken and find caseous exudate and blood in the trachea. You suspect that this may be an outbreak of infectious laryngotracheitis. Which of these findings would confirm your diagnosis?
Intranuclear inclusion bodies in tracheal epithelium
Infectious laryngotracheitis (ILT) is caused by a herpesvirus. Intranuclear inclusion bodies in the tracheal epithelium help distinguish this condition from the diphtheritic form of fowlpox. Fowlpox virus produces intracytoplasmic inclusions. Liver necrosis with large, granular basophilic intracytoplasmic inclusions is consistent with avian chlamydiosis.
Horses infected with this parasite may be predisposed to thrombosis of the cranial mesenteric artery.
S. vulgaris undergoes extensive migration after being ingested as an infective larva. They leave the intestinal tract and travel around in the cranial mesenteric artery and its branches. S. equinus and S. edentatus also migrate throughout the body and may be found in the liver, pancreas, and perirenal regions. However, these parasites are not as likely to cause thrombosis of the cranial mesenteric artery. Trichostrongylus axei is usually only a problem when horses are in pastures with ruminants as this parasite is usually found in ruminants. The larvae of T. axei will penetrate the mucosa and cause ulceration, thickening of the mucosa, and a chronic gastritis. Triodontophorus tenuicollis is a small strongyle and does not migrate outside of the intestines. This particular parasite is known for being able to cause ulceration of the colon.
A valuable horse suddenly developed severe intractable diarrhea and fever 5 days ago. The owner has been giving it oral electrolytes free choice in the water, and offering it hay, grain, and green grass. It is brought to your clinic on a normal warm summer day looking thin, dehydrated, weak, and anorectic (see photo). You do a physical exam and find T=102F (38.9 C), HR=56, RR=24, with somewhat purplish oral mucous membranes. The urine is normal but has a small volume and looks concentrated. You run a PCV (45%), WBC count (normal at 7000/microliter) and total protein (TP). The TP is low at 3.5 gm/dL and the albumin is 1.4 gm/dL indicating a protein-losing enteropathy. Of the following, what is the best treatment for the low plasma proteins in this horse?
The damaged bowel is leaking albumin out into the gut lumen, and the horse may develop other problems such as edema and poor healing ability if the protein levels are not boosted. The best way to do that in an animal with GI disease is by the IV route. Whole blood may raise the PCV to a level where sludging and circulatory problems develop in an already dehydrated horse. Another option to consider if plasma is not readily available is the use of synthetic colloidal solutions such as hetastarch.
Several pigs have died at a farm. Clinical signs included star gazing, blindness, seizures, ataxia, nystagmus, and head pressing. Histologic examination of the brain demonstrates perivascular infiltration of eosinophils. What is the most likely diagnosis?
In pigs, observation of perivascular infiltration of eosinophils in the brain is a reliable indicator of salt poisoning. Additionally, the clinical signs are consistent with this diagnosis. Salmonella would not have produced the same histologic lesions, and you would expect diarrhea. Rabies is always on the differential list, but the histologic findings are not consistent with rabies. Do you recall the diagnostic lesion for rabies? Yes, it's negri bodies. Vitamin A deficiency does not cause perivascular eosinophilic infiltration either.
A horse presents for several days of lethargy, anorexia, and bleeding from its gums. Its prothrombin time is 20 seconds, and its partial thromboplastin time is 102 seconds. Its platelet count is 48,750/uL. Its antithrombin III activity is decreased as well. What is going on in this horse?
Disseminated intravascular coagulation (DIC)
DIC can be defined by having elevated PT/PTT, thrombocytopenia, and positive D dimer (a type of fibrin degradation product). Another parameter to evaluate is the fibrinogen concentration. Fibrinogen may be low in other species during DIC but is not commonly observed in horses. Usually two of these findings are enough to diagnose DIC. Antithrombin III activity is often decreased.
Coagulopathies are not uncommon in horses with infections, diseases such as severe colitis, pleuropneumonia, or strangulating intestinal lesions. DIC is a more severe coagulopathy in which both thrombosis and hemorrhage are occurring.
A fluffed cockatiel with a recent history of anorexia and dyspnea presents to your clinic. You place the bird in oxygen for approximately an hour and then perform a physical exam. On physical exam you note coelomic distention. Blood work shows a heterophilia, increased AST, CK, and fibrinogen. What is the most likely diagnosis?
Egg yolk peritonitis
Egg yolk peritonitis can be life-threatening. Clinical signs include anorexia, fluffed feathers, coelomic distention, and dyspnea. Blood work findings are consistent with egg yolk peritonitis. If gout was the diagnosis, we would expect to see painful joints. We would not expect to see coelomic distention with aspergillosis. With egg binding you would not expect to see hyperfibrinogenemia. Additionally, cloacal straining could potentially be present. Treatment for egg yolk peritonitis involves antibiotic therapy, surgery, and anti-inflammatories.
Calcium homeostasis is extremely important in lactating animals and is controlled by two hormones, parathyroid hormone (PTH) and what other hormone?
Calcitonin is produced by the C cells of the thyroid gland in response to high calcium levels in blood. Calcitonin increases renal calcium excretion and decreases osteoclastic activity (bone resorption). PTH does the opposite and also stimulates renal production of 1,25-dihydroxycholecalciferol. This form of vitamin D stimulates intestinal cells to increase Ca absorption.
Which of the following agents is monitored by the National Poultry Improvement Plan because it is egg-transmitted and is characterized by swollen, mucus-filled infraorbital sinuses in turkeys ("infectious sinusitis")?
In turkeys, these bacteria result in swollen infraorbital sinuses. It is currently monitored in breeder flocks by serum plate agglutination test.
You examine a valuable beef bull that was recently purchased in Texas and taken to the mountains of Colorado. The pasture is a mountain meadow at 10,000 feet elevation. The bull has developed edema of the brisket and ventral thorax, submandibular edema, dyspnea and tachypnea. Rectal temperature is normal. The HR is 90, and heart sounds are clearly audible without murmurs. What is your diagnosis?
High mountain disease
The key to this question is the altitude mentioned in the question and accompanying clinical signs. Also called brisket disease and high altitude disease, this condition can be fatal and is brought on by elevations above 6000 feet. Hypoxic vasoconstriction (worse in some lines of cattle) causes pulmonary hypertension, which leads to cor pulmonale, which is secondary cardiac disease including right heart enlargement and failure.
2-year old MN DSH has recently been treated for a urethral obstruction. He went home last week from the hospital on an acidifying canned diet for this condition. The owner reports he is passing urine in moderate amounts, but he is still straining frequently. You re-examine the cat and find that the bladder is empty on palpation and the wall feels a little thickened. You are confident that the cat has not re-blocked and the cat's bloodwork shows normal electrolytes and renal values. Which of the following medications may help the cat with this problem?
This cat is likely suffering from hypertonicity of urethral muscle, which was incited from the recent obstruction and urinary catheter. This can cause spasms, which makes urinating painful and not easily controlled. Phenoxybenzamine can be used in this case to reduce internal urethral sphincter tone such that the cat may urinate more easily.
Methocarbamol is a muscle relaxant but would not directly help spasms of the urethra.
Prednisolone is not used to help reduce inflammation or spasms in the urethra and may predispose the cat to contracting a urinary infection, especially while his bladder and urethra are compromised.
Phenylpropanolamine is used to treat urinary incontinence from urethral hypotonicity most often in dogs and would be contraindicated in this case.
Amitriptyline is an anti-depressant medication that has been implicated as part of a treatment plan for cats with cystitis, although benefit has never been proven. Because cats with cystitis can flare up during times of stress, the amitriyptyline has been thought to help prevent this. This medication would not work to stop spasms in the urethra.
Which of the following is the treatment of choice for a Taenia infection in dogs?
Pyrantel and ivermectin are not known to be effective against Taenia infections. Fenbendazole is effective against Taenia pisiformis, but not other subspecies of Taenia, making it a less desirable answer choice.
A herd of pigs present for unthriftiness, slow growth, and occasional deaths. Some pigs show signs of posterior ataxia or paralysis. The farmer says his herd was previously infected with Stephanurus dentatus. Which of the following diagnostics is most appropriate to make the diagnosis of Stephanurus dentatus?
Stephanurus dentatus is the kidney worm of pigs. The parasites are often in or near the kidneys, in the ureters, or in perirenal fat. Posterior ataxia or paralysis can occur due to larvae migrating along the spinal cord. Diagnosis is usually made on necropsy or by finding ova in the urine.
A 6-month old domestic short hair cat presents for its first physical exam. Cardiac auscultation reveals a grade IV/VI holosystolic murmur on the right thorax. Thoracic radiographs were unremarkable and echocardiography showed a small turbulent jet flowing through the ventricular septum from the left ventricle to the right ventricle. Which of the following do you tell the owner?
The prognosis is very good with small ventricular septal defects and no treatment is needed
The prognosis of small VSDs is very good. Some will close by themselves within the first year of life. It is unlikely that a small VSD will cause any significant problems such as heart failure, though follow-up evaluation is warranted to monitor cardiac size and function. Large VSDs carry a guarded prognosis and require cardiac bypass for surgical correction or novel device closure via transcatheter techniques; neither of which are commonly employed in animals. Small VSDs cause a relatively more turbulent jet of blood through the small defect, causing a louder murmur than a large VSD.
A 12-year old female spayed Himalayan cat presents to you for acute onset of left hind limb lameness after leaping off of the counter to the floor this morning. The cat is non-weight bearing and very painful around the left stifle. You take a radiograph (shown below). Which of the following conclusions can you make about the cat's injury?
A pathologic fracture occurred when the cat jumped off of the counter
There is marked osteolysis of the proximal tibia with a pathologic fracture. This fracture will not heal with either rest or with rigid fixation due to the presence of underlying disease that resulted in the osteolysis. The most likely cause is a tumor of the bone. In cats, unlike dogs, many bone tumors do not have a high metastatic rate and do not necessarily require adjunct chemotherapy although histopathology would be needed to confirm the tumor type and grade.
A 9-year old Quarter Horse mare is presented for hindlimb ataxia, dog sitting (see image) and intermittent dribbling of urine. Two other horses at the same facility have recently demonstrated similar signs to varying degrees. What is the most likely cause?
Equine Herpes Myeloencephalopathy (EHM)
The most likely cause is EHM, which is associated with vasculitis of the central nervous system and associated clinical signs. Neurologic signs are usually acute and are characterized by hindlimb ataxia, hypotonia of the tail/anus, and urinary incontinence. EPM could possibly cause similar signs but is not typically seen in multiple animals on the same farm. Wobbler Syndrome and EDM typically affect young horses.
Which of these conditions is most likely to progress and cause cardiac tamponade in a dog?
Right atrial hemangiosarcoma
Cardiac tamponade comes from excessive accumulation of fluid in the pericardium resulting in an increased intrapericardial pressure impairing diastolic filling of the heart. Of the answer choices, right atrial hemangiosarcoma is the only one that results in pericardial effusion. Other causes include heart base tumors, right sided congestive heart failure, idiopathic pericardial hemorrhage, peritoneopericardial diaphragmatic hernia, infectious pericarditis, trauma, foreign body, coagulopathy, and hypoalbuminemia.
Purpura hemorrhagica is an immune complex disease of horses that leads to urticaria, edema, petechia, ecchymoses, and vasculitis. What disease is it usually secondary to?
Streptococcus equi ssp. equi
Gossypol toxicity in young ruminants can cause sudden death as result of a ___________.
What is the most common tumor of the oral cavity in the dog, as seen in the photo?
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.
Fluoride toxicity at a young age in cattle may result in permanent damage to which of the following?
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
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.
What is the appropriate treatment for a dermatitis known to be caused by a food allergy in a dog?
Feeding a diet with novel protein and carbohydrate sources or a hydrolyzed diet.
You examine a 6-year old Quarter Horse gelding for a complaint of lameness. He has a short-strided stilted gait in the forelimbs, is more painful on a hard surface than on a soft grass surface, and head nods when led in a tight circle at the trot in either direction. The hoof tester elicits pain in the posterior third of the foot on both forefeet. The hoof appears normal except that it has narrow heels. A block of the palmar digital nerves seems to result in loss of hoof tester sensitivity and an improved gait. What condition is associated with these clinical findings?
Palmar foot pain can be the result of pain from any number of structures including the navicular bone, navicular suspensory or deep digital flexor tendon, navicular bursa, or several other heel areas. Navicular disease is a term used for pain associated with any of these structures.
A recently freshened 4-year old Guernsey with a body condition score of 4/5 presents for decreased milk production, anorexia, and depression. On physical exam, she has a mild fever and is ketotic. No pings were auscultated during the physical exam and a rectal exam was unremarkable. What is the most likely diagnosis?
Fatty liver syndrome
The correct answer is fatty liver syndrome. Fat cows are more predisposed to fatty-liver syndrome when they encounter a negative energy balance. Shortly after parturition, their energy needs increase dramatically with lactation. Clinical signs are vague so you must be able to reach the answer by paying attention to the signalment. Further, an RDA will present with much more systemic signs and you will be able to hear a ping. PA toxicity and oleander toxicity are possible but less likely given the signalment and clinical signs. Remember, oleander is cardiotoxic and causes arrhythmias and PAs will cause chronic damage to the liver.
Which of the following best describes Type III hypersensitivity?
An immune complex hypersensitivity involving the interaction of circulating antigen-antibody complexes in blood vessel walls causing neutrophil emigration and tissue damage