Week 2 Feb 17 Day 1 Flashcards
What causes cutaneous larval migrans in humans? Describe the pathogenesis. Is this a self-limiting disease?
Ancylostoma. These are hookworms; when they come in contact with unprotected skin, the infective larvae penetrate the epidermis but generally cannot penetrate the basement membrane. They therefore migrate aimlessly, and the disease is usually self-limiting in humans.
Topic: Chin Acne in Canids
- Is this an acute or chronic disorder?
- This condition is typically seen in what age group? What breed?
- What is this condition characterized by?
- What can develop if this condition becomes more advanced?
- Would switching to a different water bowl material help?
- How should this be treated?
Chin acne is a chronic inflammatory disorder of young short coated animals. It is characterized by folliculitis and furunculosis. Secondary bacterial infections can develop if it becomes more advanced. There has been some association seen after contact with plastic water and food bowls, and switching to a different material may help; however, the evidence is more anecdotal and is extrapolated from studies in humans and cats. The chin and lips should be kept as clean as possible with frequent bathing and antibiotic ointment to prevent plugging of the follicles.
Some cases can be simply managed by modifying behaviors that can traumatize the chin (chasing balls) and topical antibiotics. Severe cases will need long courses of systemic antibiotics to resolve the infection and then topical corticosteroids to prevent new lesions. The papules should not be expressed, as this can increase inflammation.
Benzoyl peroxide is good choice for a topical antibiotic since it has follicular flushing action. Keep in mind that topical application of benzoyl peroxide can be irritating to the skin if overused.
Topic: Canine Heartworm
See radiograph image
Heartworm in the dog is caused by Dirofilaria immitis. The treatment of choice for heartworm is Immiticide which is given by intramuscular injection.
Topic: Canine Dilated Cardiomyopathy
**See vet prep power pages **
What type of medication is Enalapril? How does it work?
Enalapril is an ACE-inhibitor, which blunts the adverse effects of the renin-agiotensin-aldosterone system thereby reducing sodium and fluid retention.
Additionally, ACE-inhibitors cause mild vasodilation by
preventing the production of angiotensin-ll, which reduces ventricular afterload.
Lastly, enalapril and other ACE-inhibitors are protective to cardiac muscle by blunting aldosterone and other hormones which induce cardiac remodeling.
Topic: Avascular Necrosis of the Femoral Head
1. Also known as?
2. Etiology & pathogenesis of this disease.
3. Signalment. Explain why. When do patients start showing clinical signs?
4. This condition is unilateral or bilateral?
5. Diagnostics?
6. How is this condition treated?
7. What is a top differential for this disease?
- Legg-Calves-Perthes disease
- 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. Dogs are usually 6-7 months of age when they first start showing clinical signs but the age may range from 3-13 months.
- The condition can be seen bilaterally in 10-17% of patients.
- 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. - 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.
- 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.
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Describe the best/ideal candidate for urohydropulsion. Explain why
Urohydropropulsion is the expulsion of cystic calculi after anesthetizing an animal by application of manual pressure to the urinary bladder to expel the stone through the urethra. Urohydropropulsion should not be attempted in male dogs because they have long, narrow urethras compared to females and an os penis which increases the likelihood of the calculi becoming lodged in the urethra. Obesity (and large size in general) makes it more difficult to manipulate the bladder effectively.
When does the canine fetal skeleton ossify? Feline?
The correct answer is 43 days gestation. The fetal skeleton ossifies at 42-45 days in the dog and 35-39 in the cat.
A 9 year old male Labrador Retriever presents for acute onset of circling to the right, head tilt to the right, nystagmus to the left, and vomiting.
The rest of the physical exam is unremarkable. CBC, chemistry panel, urinalysis, and otic exam were unremarkable. After 14 days of supportive care, the dog has completely recovered on its own. What is the most likely disease this dog had?
A. Canine idiopathic vestibular disease (Old dog vestibular disease)
B. Otitis interna
C. Inflamed polyp in the middle ear
D. Bacterial meningitis
The correct answer is canine idiopathic vestibular disease (Old dog vestibular disease). This disease is usually diagnosed after all other vestibular causes have been ruled out. Otitis interna would be ruled out with an otic exam, CBC, and lack of pain and fever. Bacterial meningitis could be ruled out by a CBC and lack of pain and fever. Polyps in the ear rarely occur in dogs; most aural polyps occur in cats. In addition, an otic exam would rule this out
Osteolytic lesions along the distal femur are highly suspicious of osteosarcoma (OSA). Given the age and clinical history it should be your first differential. The other differential would be fungal disease such as coccidioidomycosis (Valley Fever). This fungal infection is seen predominantly in the southwestern United States, but should not be excluded without full testing. The appropriate next step to differentiate OSA from Valley Fever would be thoracic radiographs to look for metastases and fungal serology to determine exposure and antibody levels to fungal diseases. Chest films are available for review below which show metastatic disease. Of note, coccidioidomycosis can also affect the lungs, leading to an interstitial, bronchiolar, multifocal, or alveolar pattern as well.
Gold standards for diagnosis of OSA are biopsy of the affected boney lesion. Remember OSA should not cross the joint. Elevations in alkaline phosphatase and/or gross visible metastatic lesions give a worse prognosis with shorter longevity, even with aggressive treatments.
A 2 year old male castrated Husky presents for crusting and hyperkeratosis of the mucocutaneous junctions and extremities. What heritable disease is the most likely cause?
The correct answer is zinc responsive dermatosis. This disease commonly affects Huskies, Malamutes, and German Shorthaired Pointers.
The defect causes an increased requirement for zinc. Clinical signs are usually responsive to oral supplementation with zinc.
What is Familial dermatomyositis?
Familial dermatomyositis is an inflammatory disease of the skin and muscles of Collies and Shetland Sheepdogs.
What is Lupoid dermatosis
Lupoid dermatosis is a fatal disease that initially causes crusting and scaling of the dorsum and head in young German Shorthaired Pointers.
What is color dilution alopecia?
Color dilution alopecia is a heritable alopecia that develops in animals with less melanin in their hair shafts than normal; one example would be a fawn colored Doberman Pinscher.
Topic: Spinal Chord Localization (watch video)
The correct answer is C1-C5 of the spinal cord. All 4 limbs are showing signs of an upper motor neuron lesion, which would be consistent
with a C1-C5 myelopathy or multifocal spinal lesions. A C6-T2 lesion would manifest as lower motor neuron signs in the thoracic limbs
and upper motor neuron signs in the pelvic limbs. A T3-L3 lesion would manifest as upper motor neuron signs in the pelvic limbs with
normal thoracic limbs. A L4 and caudal lesion would manifest as lower motor neuron signs in the pelvic limbs with normal thoracic limbs.
Remember that multifocal lesions in different areas of the spinal cord can make neuroanatomic localization trickier.
What is the most reasonable treatment option for canine patients with a histiocytoma?
Histiocytomas are typically benign and will often present as a small, raised mass that may or may not be ulcerated. Fortunately, these masses usually regress on their own, and surgical or medical intervention is typically not necessary.
Atropine is an _____________, often used during premedication and intraoperatively to increase _______ ______. It causes a decrease in ____ secretion, ________ secretion, and _____ tone and motility. Atropine reduces the influence of the _________ nerve on the heart but does not _______ it completely. ________ is used to treat VPCs.
Atropine is an anticholinergic, often used during premedication and intraoperatively to increase heart rate. It causes a decrease in tear secretion, salivary secretion, and Gl tone and motility. Atropine reduces the influence of the vagus nerve on the heart but does not block it completely. Lidocaine is used to treat VPCs.
What is an important side effect of ketoconazole?
Ketoconazole is hepatotoxic and can cause elevated liver enzymes. It is a potent inhibitor of P450 enzymes and can significantly affect metabolism of other drugs. It can cause adrenal insufficiency and actually is sometimes used as an alternative treatment for Cushing’s.
Anorexia is a common and important side effect, especially in cats.
The kidneys and GFR are not significantly bothered by ketoconazole. Facial excoriation is a potential side effect of methimazole, not ketoconazole.
Definitive diagnosis of multiple myeloma requires satisfying at least ________ of the following criteria:
Definitive diagnosis of multiple myeloma requires satisfying at least two of the following criteria:
1. Monoclonal gammopathy
2. Radiographic evidence of osteolytic bone lesions (satisfied in this case)
3. >5% neoplastic cells or >10-20% plasma cells in the bone marrow
4. Immunoglobulin light chain proteinuria (Bence-Jones proteinuria)
Topic: Addison’s Disease
1. Primary hypoadrenocorticism causes destruction of what hormones? Where are these hormones produced?
2. The less common form of Hypoadrenocorticism is caused by?
Primary hypoadrenocorticism is caused by destruction or atrophy of all layers of the adrenal cortex, causing a deficiency in both types of corticosteroids. Remember, mineralocorticoids come from the zona glomerulosa, and glucocorticoids come from both the zona fasciculata and zona reticularis.
The less common form of hypoadrenocorticism is caused by inadequate ACTH production by the pituitary and results in a deficiency of glucocorticoids only.
Topic: Central Venous Pressure
Central venous pressure is a ________ measure of blood pressure in the _____________. __________ blood volume, venous vessel _____, and cardiac __________ determine the CVP. CVP is an _________ of preload, not a direct measurement. Cardiac output is one of the factors along with venous tone and venous blood volume in obtaining CVP.
Central venous pressure is a direct measure of blood pressure in the cranial vena cava. Venous blood volume, venous vessel tone, and cardiac output determine the CVP. CVP is an estimate of preload, not a direct measurement. Cardiac output is one of the factors along with venous tone and venous blood volume in obtaining CVP. Afterload is the force against which the myocardium must contract.
What is the most common side effect of Ivermectin?
Starting dogs on low dose (0.1mg/kg) of ivermectin and gradually increasing dose to therapeutic levels (0.6mg/kg) is recommended to monitor for signs o neurotoxicity. Starting at a low dose of ivermectin is necessary so the owner can evaluate for neurological signs. The goal is to have the owner see mild neurological signs like mydriasis and tremors and are able to stop the medication before more severe signs such as seizures and coma occur. Common signs of toxicity include ataxia, head tilt, and lethargy. Signs typically resolve within 24-48 hours after stopping ivermectin when seen. Worst-case scenarios are those with collie breeds or other dog breeds that have the ABCB1 (formerly the MDR-1) gene mutation. This leads to toxic accumulation of drugs intracellularly, leading to severe neurological signs including comas and possibly death.
Melanoma
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.
In addition to a blood glucose, all newly diagnosed diabetic patients should have what done? Explain why.
All newly diagnosed diabetic patients should have their urine cultured. Diabetics are prone to getting urinary tract infections due to the chronic presence of glucose in their urine. Any underlying infection can lead to insulin resistance and make regulation of diabetes difficult to achieve.
Fructosamine level is helpful in trying to determine if a cat actually has diabetes if their glucose level is elevated and also as a follow up to determine regulation. Cats that have markedly elevated glucose levels, glucosuria, and clinical symptoms of diabetes do not necessarily need to have a fructosamine checked at the time of diagnosis.