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ORGAN TRANSPLANTATION – CLINICAL RENAL TRANSPLANTATION IN THE
DOG AND CAT
Clare R. Gregory, DVM, Diplomate ACVS
The Comparative Transplantation Laboratory in the Department of Surgical and Radiological
Sciences, School of Veterinary Medicine, University of California, Davis, Davis, California
95616-8745
Clinical Renal Transplantation in Cats
Criteria for the renal recipient.1, 2, 3, 4,5
Renal transplantation is one method of treatment for renal insufficiency. It cannot be
regarded as an emergency treatment or "last-ditch" effort to save the life of a critically ill,
malnourished patient. Surgical intervention has to take place before all medical means of
1
therapy have been exhausted. The authors consider body weight to be a very important
indication of the status of the renal transplant candidate. If a cat has been in compensated renal
failure and starts to lose body weight, or presents in renal failure with a history of chronic weight
loss, transplantation should be considered as an option before further weight loss occurs. In the
critically ill human surgical patient, maximum physical performance deteriorates after a 10%
loss in normal body weight. Greater than a 40% weight loss is usually lethal. Previous attempts
by the authors to alter the course of physical deterioration due to decompensated renal failure via
enteral or parenteral alimentation prior to transplantation have failed. Hemodialysis, however, is
very effective in managing severely uremic patients several days prior to surgery. The authors
use hemodialysis to correct electrolyte and acid/base imbalances and lower the blood urea
nitrogen concentration to 100 mg/dl or less. Blood urea nitrogen concentrations greater than 100
mg/dl predispose cats to postoperative cerebral edema and seizures due to rapid clearance of the
blood urea nitrogen by a normally functioning renal graft. Age, plasma creatinine, blood urea
nitrogen, and other clinical pathologic assessments of renal function cannot in themselves select
a suitable patient for transplantation. All physical and biochemical parameters must be assessed
to determine the overall suitability of a candidate.
Feline candidates for renal transplantation should be free of Feline Leukemia Virus
infection, active Acquired Immunodeficiency Syndrome and free of other complicating diseases.
It appears that renal insufficiency can produce systemic hypertension in the feline patient leading
to congestive heart failure. Cats in renal failure often have systolic murmurs secondary to
anemia that may not represent significant cardiac disease. Cardiac enlargement determined by
ultrasonographic examination, gallop rhythms, and/or electrocardiographic abnormalities are
possible indications to decline a candidate for transplantation. An abdominal ultrasonographic
2
examination and intestinal biopsies should be performed if neoplasia or inflammatory bowel
disease is suspected. Immunosuppression often enhances tumor growth and inflammatory bowel
disease appears to promote acute allograft rejection.
The feline renal donor/recipient pair do not have to be related or tissue matched, but they
must be blood cross matched. The antigens present on red blood cells are also present on the
endothelium of the graft blood vessels. Preformed antibodies to these antigens will cause
clotting of the graft vessels and infarcts of the organ at the time of surgery. The feline renal
recipient must also be blood cross matched to 2 to 3 blood donor cats. The primary reason for
this is the anemia that accompanies chronic renal failure. Following rehydration of a patient
prior to surgery, packed red blood cell volumes may fall as low as 12 to 15%. One hundred
eighty to 250 milliliters of whole blood may be required to attain a packed red blood cell volume
of 30% in the renal recipient prior to surgery. Also, in our experience, some cats in chronic renal
failure are unable to accept blood transfusions, i.e. all cross match assays show agglutination of
donor red cells. In two instances, the renal disease was secondary to Lupus erythematosus. In
one other, however, no cause for the coagulopathy could be found. All cats were of the same
blood type (A). This is an important consideration if the transplant patient is traveling a great
distance to the transplant clinic. Cross matching should be done locally to ensure transfusions
can be given prior to surgery. Erythropoietin can be very helpful in controlling the anemia
associated with renal failure. Administration of erythropoietin starting 1 to 2 months prior to
surgery can greatly reduce the need for blood products.
Renal diseases successfully treated by renal transplantation in the cat include
membranous glomerulonephropathy, chronic tubulointerstitial nephritis, polycystic renal disease,
and ethylene glycol toxicosis. Cats with a suspected history of bacterial urinary tract infection
3
should have a renal biopsy performed and be subject to a 2 week cyclosporine challenge prior to
surgery. Cyclosporine is administered orally at 4 mg/kg twice daily and urine cultures are
performed 7 and 14 days following the initiation of cyclosporine treatment. Latent infections
will often become active once cyclosporine is administered. Currently we are recommending
renal transplantation for cats whose renal failure was secondary to obstruction by calcium
oxalate uroliths. However, clients must be warned that some of these cats may form additional
uroliths following transplantation that may obstruct and injure or destroy the transplanted kidney.
Cats with renal failure whose kidneys are of normal or increased size should have a biopsy
performed to rule out lymphosarcoma.
In the past, cats that had positive serum titers for Toxoplasmosis, either IgG or IgM, were
not considered candidates for immunosuppression and transplantation. Both cats and dogs have
developed fatal Toxoplasmosis infections following renal transplantation and
immunosuppression6. Currently animals with positive serum titers that undergo transplantation
are administered clindamycin or trimethoprim/sulfadiazine prior to surgery and for the life of the
patient. (LR Aronson, University of Pennsylvania, personal communication).
Trimethoprim/sulfadiazine must be used with care since this drug can enhance cyclosporine
nephrotoxicity.
Criteria for the renal donor.
The renal donor should be in excellent health and have no evidence of renal insufficiency
based on clinical pathologic testing; complete blood count, serum chemistry panel, urinalysis and
urine bacterial culture. An intravenous pyelograph is performed to assure that the donor has
two, normally shaped, and well vascularized kidneys. The feline donor should be free of Feline
Leukemia virus infection, and be blood cross match compatible and of similar weight and body
4
size of the recipient. The renal donor should have a normal life expectancy following unilateral
nephrectomy.7 Elevation in serum creatinine levels and proteinuria have been reported in human
kidney donors, and long-term monitoring of renal function has been recommended.
Preoperative preparation of the recipient.
Prior to surgery, the renal recipient is given balanced electrolyte solutions subcutaneously
or intravenously at 1.5 to 2 times daily maintenance requirements. Whole blood or packed red
blood cell transfusions are administered until a packed red cell volume of 25- 30% is achieved.
Hemodialysis is employed for cats that maintain a blood urea nitrogen concentration > 120
mg/dl despite aggressive fluid diuresis. Forty-eight hours prior to surgery, cyclosporine oral
solution (Neoral) is administered at a dose of 3-5 mg/kg every 12 hours. The cyclosporine oral
solution should be placed in gelatin capsules prior to administration. Capsule sizes #0 or #1
work well for most cats. Cyclosporine oral solution has a very unpleasant taste that causes some
cats to salivate profusely, resulting in partial loss of the dose. Clindamycin is administered to
animals with positive serum titers for Toxoplasmosis.
The morning of surgery, a blood sample is taken from the recipient 12 hours following
the last oral dose of cyclosporine. This will give a 12 hour trough blood concentration. The
authors follow whole blood concentrations of cyclosporine assayed by High Pressure Liquid
Chromatography. In cats, a concentration of 500ng/ml is maintained for the first 30
postoperative days, reducing to 250ng/ml by three months after transplantation. Prednisolone, 1
mg/kg/12 hours, orally, is also started the evening following surgery and is reduced to 0.5 to 1
mg/kg/24 hours by 1 month postoperatively if renal function is normal. If renal function starts to
deteriorate in the first weeks to months following transplantation, i.e. serum creatinine
concentrations begin to rise above 2 mg/dl, azathioprine (0.3 mg/kg/72hours) is added to the
5
immunosuppressive protocol. Cats receiving azathioprine should have blood cell counts and
serum chemistry profiles performed weekly until a safe and effective dose is found. White blood
cells counts should be maintained at >3000 /l and serum chemistry profiles should be evaluated
for evidence of hepatitis or pancreatitis.
Surgery.2,3,5,8
Two teams perform renal transplantation; one team harvests the donor kidney and closes
the abdominal wound, and one team prepares the recipient vessels and receives the kidney. The
two team approach minimizes the warm ischemia time of the donor kidney, which should be kept
to less than 60 minutes, unless preservation protocols are employed 9. The authors have not used
perfusion solutions to maintain the kidney prior to vascularization, but iced heparinized saline
solution is used to flush blood from the kidney following harvest. It is important to thoroughly
cool the kidney immediately following excision from the donor. Cold sponges should be placed
on the kidney during the implantation procedure to keep it from prematurely warming.
Anesthesia protocols vary with each patient. In general, the recipient receives atropine
(.03mg/kg) and oxymorphone (.05mg/kg) subcutaneously prior to induction. The cat is mask or
boxed induced and anesthesia is maintained using isoflurane or sevoflurane inhalant anesthesia
and oxygen. During the procedure, balanced electrolyte solutions and/or whole blood/packed red
blood cells are administered intravenously. Systemic arterial pressure is monitored via direct
arterial catheterization or by indirect measurement using Doppler ultrasonography. Hypotension
can be managed using dopamine (5g/kg/minute intravenously) and fluid boluses as necessary.
Both cats receive broad spectrum antibiotics administered intravenously just prior to surgery. As
the abdominal incision is made, the donor cat should receive mannitol ( 0.5 g/kg as a bolus
followed by a constant infusion of 1mg/kg/minute) to protect the kidney to be transplanted
6
during harvest. Mannitol significantly reduces the incidence and duration of acute tubular
necrosis associated with warm ischemia.
The donor nephrectomy is performed via a ventral midline celiotomy. Magnifying
loupes providing 3.3X to 4.5X magnification are recommended for the vascular dissection. The
vascular pedicle of the donor kidney can contain only one artery. Renal arteries may bifurcate
close to the aorta. A length of .5 cm or more is required for arterial anastomosis. If two or more
veins are present, the largest is saved for venous anastomosis. The vascular pedicle should
contain the longest vein possible, so the left kidney is explored first.
Once the kidney to be harvested is selected, the recipient team should be informed so
they can prepare the recipient vessels. It is very important to clean the donor renal artery and
vein of as much fat and adventitia as possible. The large fat pad in the renal pelvis should be
removed, being careful not to damage the ureter. Removal of the fat and adventitia from the
vessels prior to nephrectomy reduces warm ischemia time. The renal vein diameter is measured
and a sterile paper template is made to guide the size of the venotomy in the recipient’s caudal
vena cava. The ureter is isolated to the bladder. Donor nephrectomy is performed when the
recipient team is prepared to receive the kidney. Anastomosis of the renal vessels and the ureter
in the small dog and cat requires 3X to 10X magnification. The higher magnification is
necessary to suture the ureter to the bladder. The authors use an operating microscope.
The recipient post renal aorta and vena cava area isolated via a ventral midline celiotomy.
The kidney is implanted between the left renal artery and the caudal mesenteric artery. First the
aorta is occluded using vascular occlusion clamps. Using an arterotomy clamp, a 1.5 to 2 mm
defect is created in the aortic wall. The lumen of the aorta is flushed with heparinized saline
solution. The caudal vena cava is then occluded adjacent to the arterotomy site in the aorta.
7
Using the template created by measuring the donor renal vein, an oval defect is created in the
caudal vena cava. The vena cava is flushed with heparinized saline solution.
Once the recipient vessels have been prepared for implantation of the graft, the donor
kidney is harvested. The kidney is flushed with iced heparinized saline. The renal artery is
gently dilated and adventitia is excised from the distal end. The artery is anastomosed to the
aorta, end-to-side, using 8-0 nylon in a simple continuous pattern. The renal vein is then
anastomosed to the vena cava using 7-0 silk or 8-0 nylon, depending on the size of the vein, in a
simple continuous pattern. Due to a lack of visibility of the wall adjacent to the aorta, the first
side of the vein closest to the aorta is sutured inside the lumen of the vessels (back-wall
technique). Once the first side is sutured, the side away from the artery is sutured in a
conventional manner.
As soon as both the renal artery and vein are sutured, the venous occlusion clamp is
removed, followed by the arterial occlusion clamp. Hemorrhage is controlled by pressure, or by
the addition of simple interrupted sutures if needed.
The ureter is sutured to the bladder in the following manner.1,10.11 A 1 centimeter incision
is made in the seromuscular layer of the bladder on the ventral surface. The mucosa will bulge
through the incision. A 3 to 4 mm incision is made in the mucosa at the caudal aspect of the
seromuscular incision. The periureteral fat is excised from the distal 5 mm of the ureter, and the
end of the ureter is spatulated. Using 8-0 vicryl in a simple interrupted pattern, the mucosa of the
ureter is sutured to the mucosa of the bladder. The proximal and distal sutures are placed first.
A 5-0 polypropylene stent is used to check patency of the stoma. Once the mucosal layers are
opposed, the seromuscular layer is closed over the ureter using 4-0 absorbable suture in a simple
interrupted pattern.
8
The kidney capsule is fixed to the abdominal wall by creating a peritoneal/transversus
abdominus muscle flap based on a ventral pedicle. The flap is sutured to the renal capsule using
simple interrupted sutures of 5-0 polypropylene. Fixing the kidney to the abdominal wall
prevents torsion of the kidney on its pedicle with resulting ischemia and loss of the graft. To
provide nutritional support during the postoperative period, a gastrostomy or esophagostomy
tube is placed prior to recovery from anesthesia.
In dogs, the transplanted kidney can be placed in the iliac fossa of the recipient. The
renal vein is anastomosed end-to-side to the external iliac vein using 4-0 or 5-0 silk in a
continuous pattern. The renal artery is anastomosed end-to-end with the external iliac artery
using 4-0 or 5-0 polypropylene suture in a simple interrupted pattern. As in the cat, a
peritoneal/muscle flap is used to secure the kidney to the abdominal wall. The iliac vessels are
no longer used as recipient vessels for feline transplant patients. While not a problem in dogs,
loss of the iliac blood supply in cats can result in ipsilateral hind limb weakness, paralysis and
ischemia.8
Unless there is evidence of bacterial nephritis or severely enlarged polycystic kidneys,
the authors do not remove the recipient’s native kidneys at the time of transplantation. These
kidneys are available to provide some support if the transplanted organ should fail, and can be
removed at a later date if indicated.
Postoperative care of the renal recipient.
During and following surgery, it is imperative to keep the transplant patient warm and
the hematocrit and systolic blood pressure within normal limits. Avoid unnecessary stress and
handling. Postoperative pain is controlled by the administration of oxymorphone (0.05 mg/kg
subcutaneously) as needed. The recipient receives balanced electrolyte solutions supplemented
9
to correct electrolyte or acid/base abnormalities.1,11 Urine specific gravity is followed twice daily
via free catch of the urine. Urine specific gravity is usually > 1.020 by the third postoperative
day. Packed blood cell volume, total plasma protein level, serum electrolyte levels and the
plasma creatinine concentration are assessed 3 to 4 times daily until renal function is stable.
During the early postoperative period needless venapuncture, blood sampling and patient
handling should be avoided. If the surgery is a technical success, the urine specific gravity will
be increased, and the plasma creatinine will be decreased by the third postoperative day. The
recipient will look clinically improved and normal appetite usually returns by postoperative day
3 to 5. If the graft has failed or has delayed function, the recipient will be depressed and
anorectic. The urine will remain isosthenuric. Approximately 3 days following surgery, an
ultrasonographic examination of the transplanted kidney and ureter can be performed if renal
function is not returning to normal. If there is good perfusion of the graft without evidence of
hydronephrosis or hydroureter secondary to obstruction, the graft may have suffered acute
tubular necrosis consistent with delayed graft function. As long as the kidney remains perfused,
function can start as late as 3 weeks following surgery.
Hypertension is a common complication that can occur within the first 72 hours after
surgery.13,14 Cats can develop hypertension (systolic blood pressure > 170 mm/Hg) and are at
higher risk for neurologic disorders such as ataxia, blindness, seizures and stupor. Occasionally,
uncontrollable seizures and death can result. Controlling hypertension has significantly reduced
the frequency of these complications. Indirect, systolic blood pressure is measured by ultrasonic
Doppler every hour for at least 24 hours after surgery, and then at decreasing intervals over the
next 48 hours. When the systolic blood pressure is > 170 mm/Hg, hydralazine (2.5 mg total
dose/subcutaneously) is given. If the systolic blood pressure has not decreased to normal within
10
15 to 20 minutes, a second dose is given. In the rare case that the hypertension is refractory to
hydralazine therapy, acetylpromazine (0.01 mg/kg, intravenously, subcutaneously) is
administered. Rarely, transplant patients can develop a lethal sensitivity to cyclosporine termed
hemolytic uremic syndrome. 15 Cats become uremic with a coexisting hemolytic anemia and
thrombocytopenia. The transplanted kidney is lost to ischemia produced by diffuse vascular
thrombosis. Currently there is no treatment for this syndrome in cats.
If the transplant recipient is not eating well by 24 hours following surgery, feedings
are begun using the gastrostomy or esophagostomy tube. Normal caloric intake is attained over
24 to 48 hours. Cyclosporine is administered at levels necessary to achieve trough whole blood
concentrations of 500 ng/ml. Prednisolone is administered at 1.0 mg/kg/12 hours, orally, and is
tapered to 0.5 to 1 mg/kg/24 hours by four weeks postoperatively. Erythropoietin can be
administered if the hematocrit remains below 25%.
Transplant recipients are discharged from the hospital when they have achieved an
adequate nutritional intake and the cyclosporine blood level has stabilized. The feeding tube is
left in place until the cat has completely acclimated at home.
Long-term management of the renal recipient.
Management of the transplant patient must be coordinated with the client, the local
veterinarian(s), and the transplant center. Examinations are initially performed weekly by the
local veterinarian. Packed blood cell volume, total serum protein concentration, plasma
creatinine concentration, whole blood cyclosporine concentration and a urinalysis are performed.
Periods between examinations are gradually extended to 3 or 4 weeks. The authors recommend
that a complete blood count should be performed monthly, and a serum chemistry panel,
11
urinalysis with urine culture and cardiac consult be performed 3 times a year.
During the first year after transplantation, the most common complications that occur are
acute rejection, infections, and the development of cancers.6,16,17,18,19,20 Acute rejection can often
be attributed to poor owner compliance in giving medications and having cyclosporine blood
concentration assays performed on a regular basis. Acute rejection is an emergency situation
that must be treated quickly and aggressively with injectable cyclosporine (Sandimmune,
[Norvartis AG, Basel, Switzerland], 6.6 mg/kg once daily over 4 to 6 hours), corticosteroids and
the intravenous administration of balance electrolyte solutions. Cats do not show illness
associated with acute rejection, so rising creatinine concentrations are considered grounds for
treatment unless obstructive uropathy can be proven by ultrasonographic evaluation of the
kidney and ureter.21,22 In cats, slow, chronic elevations of serum creatinine, in the face of
adequate blood levels of cyclosporine, are treated with the addition of azathioprine (0.3
mg/kg/72 hours) to the immunosuppressive protocol. The white blood cell count and hepatic
enzyme concentrations must be monitored and the dose adjusted as necessary to prevent severe
leukopenia (<3000 cells/l) or hepatitis.
Transplant patients are susceptible to infections. Viral, bacterial, parasitic, coccidian,
protozoal, and fungal infections can all develop. When treating bacterial infections,
aminoglycoside and trimethoprim/sulfa antibiotics must be avoided as they are nephrotoxic when
combined with cyclosporine. When adding any medication to the immunosuppressive protocol,
check the drug insert that is provided with cyclosporine. Many agents can raise or lower
cyclosporine whole blood concentrations by interfering or promoting cytochrome P-450 enzyme
activity.
Immunosuppressed patients are also at an increased risk for the development of cancer.
12
The most common types are lymphoma and squamous cell carcinoma. Transplant recipients also
develop diabetes mellitus with an increased frequency. Diabetes can be temporary or a chronic
problem. Insulin therapy can provide long-term control.
Clinical Renal Transplantation in the Dog
There are only a few differences in the technical aspects of renal transplantation between the
dog and the cat. Most dogs, due to their size, do not require magnification for anastomosis of the
vessels, although 2X to 3X magnifying loops are very helpful. . In addition to implanting the
graft on the terminal aorta and vena cava, the external iliac artery and vein can be used as
recipient vessels for the transplanted kidney. The iliac vessels should not be used for the
recipient vessels in cats since loss of the iliac blood supply in cats can result in rear limb
weakness, paralysis or ischemia. 8
For ease of anastomosis, a left donor kidney is placed in the right iliac fossa of the recipient,
and vise versa. If necessary, a donor kidney can be placed in the ipsilateral iliac fossa of the
recipient, however, the arterial anastomosis will be more difficult to perform. The chosen iliac
fossa is prepared for end to end anastomosis of the renal artery to the iliac artery and end to side
anastomosis of the renal vein to the iliac vein. The iliac artery is isolated, and a bulldog or other
vascular clamp is used to occlude it near the aortic bifurcation. The iliac artery is then ligated
distally, near the femoral ring, and is severed. The free length of the artery is flushed clean of
blood using heparinized saline solution. The end of the artery is gently dilated and the adventitia
is excised from the proximal 3-5 mm. The iliac vein lies deep to the artery in fat and adventitia.
It is isolated over the same area as the artery, gaining as much free length as possible. The iliac
vein has multiple tributary veins in this region that must be ligated. Careful inspection dorsal and
caudal to the vein will reveal these branches. Once the tributary veins have been ligated, two
13
vascular clamps are placed on the iliac vein as far apart as possible. The first is placed distally,
and the second is placed proximately. A section of the wall is excised from the iliac vein that is
slightly larger than the diameter of the donor renal vein. It is important to create a defect in the
vein wall and not just a slit. The vein is flushed clean of blood using heparinized saline solution.
Two 4-0 to 6-0 sutures of silk are placed at each end of the defect in the vein wall. Each
suture is subsequently placed at the cranial or caudal aspect of the renal vein and tied. The renal
vein is then anastomosed to the iliac vein using a simple continuous pattern on both the medial
and lateral sides of the vessels.
Following completion of the venous anastomosis, the renal artery and iliac artery are
isolated near the midline of the recipient. The arteries are anastomosed using 5-0 to 8-0 nylon or
polypropylene in a simple interrupted pattern. Once arterial anastomosis is complete, the
vascular clamps are removed from the vein, and then the artery. Some hemorrhage is expected,
can be controlled with light pressure, and should stop within a few minutes. Large defects in the
arterial anastomosis will have to be controlled by placement of additional sutures.
Ureteroneocystostomy is performed using the same method described for the cat. The kidney
capsule is attached to the adjacent abdominal wall using simple interrupted sutures of 3-0
polypropylene or a peritoneal/transversus abdominis muscle flap.
Following renal transplantation, dogs are highly likely to develop intestinal
intussusceptions. Two treatments have resulted in the prevention of this condition that develops
post-operatively. First, morphine, 0.5 mg/ml is administered subcutaneously as a premedication
and postsurgically at 0.5 mg/kg subcutaneously every 3 to 4 hours to control pain.23 Second,
enteroplication is performed after the renal transplant procedure is completed. The seromuscular
layers of the bowel are joined using simple interrupted sutures of 3-0 polydioxanone. 24
14
Due to the difficulty of immunosuppressing the dog rejection response, few renal
transplants have been performed clinically for canine renal failure patients. The primary
difference in transplantation between the dog and cat is selection of the donor. Using
cyclosporine and prednisolone to achieve immunosuppression, the authors will only use mixed
lymphocyte response matched, related donors. The new formulation of cyclosporine, with
conventional or newly developed agents, has proven to successfully control the canine rejection
response.25,26 With the use of MHC-nonmatched donors, the authors employ one of two
immunosuppressive protocols: 1)cyclosporine and leflunomide (4-6 mg/kg/24 hours) or 2)
cyclosporine (Neoral), azathioprine (1-5 mg/kg every 48 hours) and prednisolone (1 mg/kg/24
hours). Cyclosporine is administered at a dose that will achieve a trough whole blood level of
500 ng/nl. Leflunomide is administered at a dose necessary to maintain a trough plasma blood
concentration of 20 g/ ml. Azathioprine dosage is adjusted to avoid leukopenia and hepatitis.
The dose of prednisolone is reduced over 1 to 3 months depending on the serum creatinine
concentration and degree of side effects suggestive of Cushing’s Syndrome. In a long on-going
study, Mathews et al employed antithymocyte serum, cyclosporine, azathioprine and
prednisolone for immunosuppression of unrelated dog donor-recipient pairs. A median survival
time of 8 months was achieved with 2 dogs surviving more than 2 years.27 In a recently
completed clinical study, the authors found that the combination of cyclosporine, azathioprine
and prednisolone prevented renal allograft rejection in 15 dogs. Three dogs are currently alive
24 to 50 months following surgery. Five of the dogs died in the perioperative period due to the
development of systemic thromboembolism. Four of the dogs died due to the development of
lethal bacterial infections. Renal allograft rejection can be controlled in the dog. However, a
balance must be maintained between the control of rejection and the development of lethal
15
infections. Due to the hypercoagulable state present in the canine renal failure patient,
perioperative anticoagulation therapy must be employed (Gregory CR et al. Unpublished paper
in review).
Canine renal transplantation is still in the development phase. The work of Mathews et al
and our own studies have been invaluable in highlighting the techniques and the difficulties, both
clinically and financially. Over the next several years, case selection, immunosuppressive
management and anticoagulation strategies will be further refined, and outcomes will improve.
Client Education
Before performing renal transplantation for the dog or cat, clients must be fully
informed of the risks, responsibilities and costs associated with the procedure. Clients must be
able to administer medications orally two times a day for the life of their pet. Fractious cats and
dogs are not good candidates because of the extensive nursing required in the perioperative
period and the need for regular examinations by the local veterinarian. Clients must have access
to a 24 hour emergency facility. Finally, clients must understand that no matter how carefully
selected and managed, their cat or dog may die due to the stress of the procedure or failure of the
graft to function.
Feline and canine renal transplantation is becoming more widely available
in the United States and is also performed in Australia, Japan and Europe. Survival rates have
improved with careful patient selection, better perioperative care and monitoring, and the
introduction of the microemulsified form of cyclosporine (Neoral). Renal transplantation can
offer long-term survival with a normal quality of life for cats and dogs with renal failure.
References:
Bernsteen L, et al. Renal transplantation in cats. Clin Tech Sm An Prac
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15:40, 2000
2 . Gregory CR: Renal transplantation in the cat. Comp Cont Ed Pract Vet
15:1325, 1993
3. Gregory CR, Gourley IM: Organ transplantation in clinical veterinary
medicine. In: Slatter D (ed): Textbook of Small Animal Surgery, 2nd
Ed, WB Saunders Company, Philadelphia, 1993, pp 95-101.
4. Kochin E.J. and Gregory CR: Renal transplantation:patient selection
and postoperative care. In: Consultations in Feline Internal Medicine, 2nd Ed, WB Saunders
Company, Philadelphia, 1993 pp 339-342.
5. Gregory CR, Bernsteen L: Organ Transplantation in Clinical Veterinary Practice. In Slatter
D, ed.: Textbook of Small Animal Surgery, 3rd ed. Philadelphia, WB Saunders Co, 2003, p
122.
6. Bernsteen L, et al: Acute toxoplasmosis following renal transplantation in
three cats and a dog. JAVMA 215: 1123, 1999.
7. Lirtzman R A, Gregory CR. Long-term renal and hematologic effects of
uninephectomy in healthy feline kidney donors. JAVMA 207: 1044,
1995.
8. Bernsteen L, et al: Comparison of two surgical techniques for renal transplantation in
cats. Vet Surg 28:417, 1999
9. McAnulty JF: Hypothermic storage of feline kidneys for transplantation: successful ex
vivo storage up to 7 hours. Vet Surg 27:312, 1998
10. Kochin E.J. and Gregory CR. Evaluation of a method of ureteroneocystotomy
in the cat. JAVMA 202: 257,1993.
17
11. Gregory CR et al: A mucosal apposition technique for ureteroneocystostomy after renal
transplantation in cats. Vet Surg 25:13, 1995.
12. Wooldridge JD, Gregory CR: Ionized and total serum magnesium concentrations in
feline renal transplant recipients. Vet Surg 28:31, 1999.
13. Gregory CR et al: Central nervous system disorders after renal
transplantation in cats. Vet Surg 26:386, 1997
14. Kyles A E, et al: Management of hypertension controls postoperative
neurologic disorders after renal transplantation in cats. Vet Surg 28:436, 1999.
15. Aronson LR, Gregory CR: Possible hemolytic uremic syndrome in three
cats after renal transplantation and cyclosporine therapy. Vet Surg 28:135,
1999.
16. Gregory CR et al. Preliminary results of clinical renal allograft transplantation
in the dog and cat. J Vet Int Med 1:53, 1987
17. Gregory CR et al: Feline leukemia virus-associated lymphosarcoma
following renal transplantation in a cat. Transplantation 52(6):1097, 1991
18. Gregory CR et al: Renal transplantation for treatment of end-stage renal
failure in cats. JAVMA 201:285, 1992
19. Gregory CR et al: Oxalate nephrosis and renal sclerosis after renal
transplantation in a cat. Vet Surg 22:221, 1993
20. Mathews KG, Gregory CR: Renal transplants in cats: 66 cases (1987-
1996). JAVMA 211:1432, 1997.
21. Nyland TG et al: Ultrasonographic evaluation of renal size in dogs with
acute allograft rejection. Vet Radiol Ultrasound 38:55, 1997
18
22. Pollard R et al: Ultrasonographic evaluation of renal autografts in normal
cats. Vet Radiol Ultrasound 40:380-385, 1999.
23. McAnulty JF, Southard JH, Belzer FO: Prevention of postoperative intestinal
intussusception by prophylactic morphine administration in dogs used for organ
transplantation research. Surgery 105: 494, 1989
24. Kyles AE, Gregory CR, Griffey SM et al. Modified noble placation for the prevention of
intestinal intussusception after renal transplantation in dogs. J Invest Surg 16: 161, 2003
25. Bernsteen L, Gregory CR, Kyles AE, et al. Microemulsified cyclosporine-based
immunosuppression for the prevention of acute renal allograft rejection in unrelated dogs:
preliminary experimental study. Vet Surg 32: 213, 2003
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