small mammals 4 pt 2 Flashcards
1
Q
Urolithiasis Etiology
A
- Maximize Ca absorption from diet; fractional excretion 45-60% (c.f. 2%) as CaCO3
2
Q
Urolithiasis result
A
- Ca “sand” in bladder
- Renal, ureteral, cystic, or urethral calculi
3
Q
Urolithiasis Predisposing Factors
A
- Limited exercise
- Free-choice pellets
- High-Ca greens, alfalfa
- Vitamin/mineral supplement
- Obese
4
Q
rabbits urolithiasis summary
A
- Any combination of cystic, urethral, renal, and ureteral calculi.
- Nutrition, anatomy, and, rarely, infection involved.
- Rabbits maximize absorption of dietary calcium, independent of vitamin D3 levels;
have high blood calcium levels; excess excreted as calcium carbonate in urine;
fractional excretion 45-60% (compared to 2% in other mammals). - Hypercalciuria common in pet rabbits; calcium “sand” in bladders.
- Rabbits with either urolithiasis or hypercalciuria often have limited exercise, are fed a diet of free-choice of pellets, high-calcium greens, or alfalfa hay, and tend to be obese; may have a history of vitamin or mineral dietary supplementation.
5
Q
Urolithiasis clinical signs
A
- Depression
- Anorexia
- Weight loss
- Lethargy
- Hematuria
- Anuria, stranguria
- Hunched posture, grinding of teeth
- Urine scald of the perineum
<><> - Clinical signs of hypercalciuria or urolithiasis are depression, anorexia, weight loss, lethargy, hematuria, anuria, stranguria, a hunched posture, grinding of teeth, and urine scald of the perineum; may be subclinical.
6
Q
Urolithiasis Dx
A
- Imaging
- Urinalysis +/- culture
- CBC and biochemistries
<><> - Urinalysis usually identifies crystalluria; anhydrous calcium carbonate, ammonium
magnesium phosphate (triple phosphate), and calcium carbonate monohydrate crystals are common; proteinuria and hematuria; If bacteria, culture a sample collected by cystocentesis (Pseudomonas and E. coli can cause cystitis). - CBC and plasma chemistries - renal function.
7
Q
Urolithiasis treatment
A
- Endoscopic removal, if possible
- Surgery
- Dietary changes
> Grass hay, minimal pellets, low- Ca greens, stop any supplements
> Increase soft water intake - Increase exercise, decrease weight
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Treatment depends on the location and severity. - Minimally invasive, endoscopic techniques preferred.
- Cystotomy.
- Urohydropulsion.
- Nephrotomy; guarded prognosis.
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Dietary changes are an important part of treatment and prevention. - Decrease dietary calcium (grass hay, low amount of timothy hay-based
pellets, low calcium greens) - Increase dietary water intake (soft water); bowl, not nipple.
- Discontinue any vitamin or mineral supplementation.
- Decrease caloric intake and increase exercise are helpful.
- Urinary acidifiers are ineffective because rabbits are herbivores with
naturally alkaline urine.
8
Q
Uterine Adenocarcinoma etiology
A
- Most common neoplasia of
female rabbits - Slow development, often multicentric, local invasion, metastases within 1-2 years
9
Q
Uterine Adenocarcinoma predisposing factors
A
- Intact female!
- Age
- Breed - tan, French Silver, Havana, Dutch
10
Q
Uterine Adenocarcinoma in rabbits summary
A
- The most common neoplasia of female rabbits.
- Age is the most important factor, independent of breeding history.
- Certain breeds (tan, French silver, Havana, and Dutch), greater than 4 years old,
have an incidence of 50% to 80%. - A slowly developing tumor, with local invasion, and hematogenous metastasis
within 1-2 years. - Papillary or tubular/solid types.
11
Q
Uterine Adenocarcinoma clinical signs
A
- Hematuria or vaginal
discharge - Depression,anorexia, dyspnea
- Cystic mammary glands
<><> - Clinical signs include hematuria or a serosanguineous vaginal discharge (17%); also, depression, anorexia, and dyspnea.
- Cystic mammary glands often develop concurrently.
- Diagnosis relies on the palpation of an enlarged uterus and/or uterine nodular
masses (1-5 cm in diameter). - Often multicentric, involving both uterine horns.
12
Q
unterine adenocarcinoma Dx
A
Ultrasound is better than radiographs; then check for pulmonary metastases with
radiographs or CT examination.
13
Q
Uterine Adenocarcinoma treatment
A
- Ovariohysterectomy if contained
- X-ray thorax every 3-6 months for 1-2 years
<><> - Ovariohysterectomy is curative if the tumor is contained.
- Re-examine every 3-6 months for 1-2 years for pulmonary metastases.
- Successful chemotherapy for metastasis of this tumor has not been reported.
- Prevent by spaying, ideally between 8 and 12 months; alternatively, semi-annual
health examinations, including radiographs.
14
Q
Uterine Adenocarcinoma prevention
A
- Spay at 8-12 months
- Semi-annual health examinations, including x-rays
15
Q
Lymphoreticular Neoplasia etiology
A
- Common, unknown cause
- Include
- Generalized/multicentric
lymphoma – most common - Cutaneous lymphoma
- Lymphoid leukemia
- Thymic lymphoma
- Thymic carcinomas / thymomas – epithelial component +/- lymphoid cells – ↑ since 1990s
16
Q
Lymphoreticular Neoplasia summary
A
Neoplasia of the lymphoreticular system is common in rabbits.
* Most have been diagnosed as generalized or multicentric lymphoma;
however, cutaneous lymphoma, lymphoid leukemia, thymic lymphoma,
and thymomas are described.
* Since the 1990s, thymic neoplasia in rabbits has been reported commonly.
Etiology
* The cause of lymphoreticular neoplasia in rabbits is unknown and
multifactorial
* Suggestions of genetics and oncogenic virus; unproven
Types of Lymphoreticular Neoplasia * Multicentric Lymphoma
> Most common lymphoproliferative disease; a variety of breeds, all ages.
* Cutaneous Lymphoma
* Leukemia
* Thymic Lymphoma
* Thymoma/ Thymic Carcinoma
17
Q
Thymomas etiology
A
- In rabbits, thymus is large and persists in adult
- Benignneoplasmsof epithelial cells (c.f., thymic carcinoma / lymphoma)
- Slow-growing,locally invasive, rare local metastases
18
Q
thymomas defnition
A
- Thymomas are tumors originating from the epithelial cells of the thymus. In
contrast to other species, the thymus of rabbits is large and persists into
adulthood - The thymic cells may become neoplastic, giving rise to both benign
(thymoma) and malignant (thymic lymphoma, thymic carcinoma) tumors,
with benign being the most common form - Thymomas are slow-growing tumors that invade local tissue and
metastasize locally with a low occurrence
19
Q
Thymomas clinical signs
A
- Range from incidental findings to progressive dyspnea and exercise intolerance
- Bilateral exophthalmos
- Head, neck, and forelimb
edema - Pleural effusion
- Other paraneoplastic syndromes: systemic immunopathy, hemolytic anemia, exfoliative dermatitis
<><><><> - Signs range from an incidental finding to progressive dyspnea and exercise
intolerance - Bilateral exophthalmos
- Head, neck, and forelimb edema
- Pleural effusion
- Other paraneoplastic syndromes: systemic immunopathy, hemolytic
anemia, exfoliative dermatitis
20
Q
Thymomas Dx
A
- History
- PE–bilateral exophthalmos, absence of breath sounds, caudal heart displacement
- CBC – anemia
- X-rays, US, FNA
- CT if radiation planned
<><><> - History and clinical signs are usually suggestive of a mass in the cranial
mediastinum - Physical examination abnormalities: position-dependent worsening or
improving of bilateral exophthalmos, decreased compliance of the thoracic wall, absence of breath sounds in the cranial thorax, caudal displacement of the heart and ictus cordis on auscultation - CBC - anemia
- Biochemistry profile - hypercalcemia possible
- Thoracic radiographs – the presence of a soft tissue mass in the cranial
mediastinum (and potential accompanying pleural effusion) - Thoracic ultrasound - soft tissue mass in the cranial mediastinum
- Ultrasound guided FNA - r/o include: lymphoma, abscess, thymic
hyperplasia, thymic carcinoma, thymoma - Not always diagnostic but often is!
21
Q
Thymomas treatment and outcomes
A
- None – median survival
time (MST) 92 days - Surgical excision associated with high mortality rates (50-71.4%)
- Steroids – MST 270 days
- Adaptive radiation therapy
- 4-5 weekly sessions
- Greatest decrease after the first session
- MST 2 years
<><><><>
Initial database for stabilization / clinical endpoints - Blood pressure (reliable to diagnose hypotension on the front limb)
- Pulse, heart rate, CRT
- Body temperature
- Blood gases (collect enough blood for CBC and biochemistry if possible)
- Urinary specific gravity
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Stabilization - If present in respiratory distress, oxygen therapy
- Fluid support if needed
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Treatment - Radiation therapy (ideal)
> Typically, 4-5 sessions needed
> May need to replan and abort session if mass has shrunk a lot - Surgical excision via thoracotomy (not typically recommended)
> High risk procedure with high perioperative and postoperative morbidity and mortality
> Approach: median sternotomy preferred - Chemotherapy (not typically recommended)
- Meloxicam 0.5 mg/kg PO q12h
- Assist feed as necessary
22
Q
Spinal Cord Trauma etiology
A
- UsuallyL6-L7
23
Q
Spinal Cord Trauma clinical signs
A
- Paraplegia
- Loss of deep pain perception, skin sensation
- Loss of motor control of urinary bladder and anal sphincter
24
Q
Spinal Cord Trauma summary
A
- The most common cause of acute posterior paralysis is a vertebral fracture (or luxation).
- The most common site is the lumbosacral region (L6-L7); however, can occur at any site.
- In addition to paraplegia, neurologic signs may include loss of deep pain perception, skin sensation, and motor control of the urinary bladder and anal sphincter, depending on the amount of compromise to the spinal cord.
25
Q
Spinal Cord Trauma Dx
A
- X-rays
26
Q
Spinal Cord Trauma treatment
A
- Conservation if SC not transected – cage rest for weeks / months, analgesics, NSAIDs
- May require manual expression of bladder, perineal care
- Carts can be used
- Euthanasia
