small mammals 4 pt 2

Question 1

Urolithiasis Etiology

Answer 1

• Maximize Ca absorption from diet; fractional excretion 45-60% (c.f. 2%) as CaCO3

Question 2

Urolithiasis result

Answer 2

• Ca “sand” in bladder
• Renal, ureteral, cystic, or urethral calculi

Question 3

Urolithiasis Predisposing Factors

Answer 3

• Limited exercise
• Free-choice pellets
• High-Ca greens, alfalfa
• Vitamin/mineral supplement
• Obese

Question 4

rabbits urolithiasis summary

Answer 4

• 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.

Question 5

Urolithiasis clinical signs

Answer 5

• 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.

Question 6

Urolithiasis Dx

Answer 6

• 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.

Question 7

Urolithiasis treatment

Answer 7

• 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
  <><>
  Treatment depends on the location and severity.
• Minimally invasive, endoscopic techniques preferred.
• Cystotomy.
• Urohydropulsion.
• Nephrotomy; guarded prognosis.
  <><>
  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.

Question 8

Uterine Adenocarcinoma etiology

Answer 8

• Most common neoplasia of
  female rabbits
• Slow development, often multicentric, local invasion, metastases within 1-2 years

Question 9

Uterine Adenocarcinoma predisposing factors

Answer 9

• Intact female!
• Age
• Breed - tan, French Silver, Havana, Dutch

Question 10

Uterine Adenocarcinoma in rabbits summary

Answer 10

• 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.

Question 11

Uterine Adenocarcinoma clinical signs

Answer 11

• 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.

Question 12

unterine adenocarcinoma Dx

Answer 12

Ultrasound is better than radiographs; then check for pulmonary metastases with
radiographs or CT examination.

Question 13

Uterine Adenocarcinoma treatment

Answer 13

• 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.

Question 14

Uterine Adenocarcinoma prevention

Answer 14

• Spay at 8-12 months
• Semi-annual health examinations, including x-rays

Question 15

Lymphoreticular Neoplasia etiology

Answer 15

• Common, unknown cause
• Include
• Generalized/multicentric
  lymphoma – most common
• Cutaneous lymphoma
• Lymphoid leukemia
• Thymic lymphoma
• Thymic carcinomas / thymomas – epithelial component +/- lymphoid cells – ↑ since 1990s

Question 16

Lymphoreticular Neoplasia summary

Answer 16

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

Question 17

Thymomas etiology

Answer 17

• In rabbits, thymus is large and persists in adult
• Benignneoplasmsof epithelial cells (c.f., thymic carcinoma / lymphoma)
• Slow-growing,locally invasive, rare local metastases

Question 18

thymomas defnition

Answer 18

• 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

Question 19

Thymomas clinical signs

Answer 19

• 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

Question 20

Thymomas Dx

Answer 20

• 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!

Question 21

Thymomas treatment and outcomes

Answer 21

• 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
  <>
  Stabilization
• If present in respiratory distress, oxygen therapy
• Fluid support if needed
  <>
  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

Question 22

Spinal Cord Trauma etiology

Answer 22

• UsuallyL6-L7

Question 23

Spinal Cord Trauma clinical signs

Answer 23

• Paraplegia
• Loss of deep pain perception, skin sensation
• Loss of motor control of urinary bladder and anal sphincter

Question 24

Spinal Cord Trauma summary

Answer 24

• 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.

Question 25

Spinal Cord Trauma Dx

Answer 25

• X-rays

Question 26

Spinal Cord Trauma treatment

Answer 26

• 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