This page covers some less
commonly used treatments.
Steroids are not a routine part of CKD treatment,
but may be necessary in some cases.
Stem cell transplants have been used for many years
to treat joint problems in horses and dogs and are now being
researched and used for cats with CKD.
Kidney transplants are not widely available and are
extremely expensive, but are covered briefly below.
Steroids are not a routine or essential treatment for CKD, and
corticosteroids should not normally be used in the renally impaired, but you
may sometimes be advised to use corticosteroids for a specific purpose, for
example if your cat also has IBD (inflammatory bowel disease).
In the UK, you may be offered anabolic steroids as a
general "pick me up" or to stimulate appetite. In the USA,
steroids are used much less often.
Steroids may be given orally or via
injection, but if you give them via injection (which is usually done only
once a week or even once a month), you will often notice that the effects
are wearing off by the time the next injection is due.
If you do use steroids, opt for anabolic ones if possible, and your vet should monitor
liver values, because these sometimes increase with steroid use, in which
case the steroids should be discontinued.
Corticosteroids
In general medicine, corticosteroids tend to be used for their
anti-inflammatory effects. They are not normally appropriate for CKD cats,
though may be prescribed for cats with
elevated calcium levels.
Corticosteroids which may be used in veterinary
medicine include prednisone and prednisolone (see below), budesonide and
dexamethasone.
PetCoach
has detailed information on corticosteroids.
Prednisone and Prednisolone
If your vet prescribes corticosteroids, it is quite probable
that you will be offered prednisone or prednisolone, commonly referred to as
pred. Pred is usually given in pill form.
Cats metabolise prednisolone better than
prednisone. Tthey have to convert prednisone into
prednisolone in their bodies anyway before they can use it,
so it is usually better to give prednisolone in the first place.
Bioavailability and activity of prednisone and
prednisolone in the feline patient (2004) Graham-Mize
CA & Rosser EJ
Veterinary Dermatology15(s1), pp 10
supports this view.
Glucocorticoid use in cats
(2010) Lowe A Veterinary Medicine says
"In cats, the absorption and conversion of prednisone to prednisolone is
less efficient, and after the oral administration of prednisone, only about
21% of the drug occurs in the bloodstream as the active form prednisolone.
For this reason, prednisone and prednisolone should not be considered
bioequivalent in cats, and the active form, prednisolone, should be used
preferentially."
These medications can have serious side effects with long-term use, including triggering diabetes,
fluid retention,
high blood pressure,
and masking or increasing the risk of infections. They may also increase
stomach acid and in the worst
case may cause stomach ulcers and
gastrointestinal bleeding, not
ideal for a CKD cat.
Corticosteroids commonly cause increased drinking and increased urination.
Chronic renal insufficiency and its associated
disorders: kitty kidneys and the kitchen sink
(2007) Scherk M The 2007 Nestlé Purina Veterinary Symposium on
Companion Animal Medicine says "Should corticosteroids
be part of therapy (e.g. inflammatory bowel disease or small airway disease,
polyuria may worsen."
According to
Plumb's Veterinary Drug Handbook,
corticosteroids may cancel out the effects of
calcitriol. This is because calcitriol increases calcium absorption, whereas
corticosteroids inhibit calcium absorption.
NSAIDs should not be used at the same time as corticosteroids.
If for some reason you are using corticosteroids, these should never be
suddenly discontinued.
Veterinary Partner
states that: the dose must be tapered. This is because using
corticosteroids may suppress the adrenal glands' ability to produce
cortisone naturally, whereas.tapering the dose minimises the risk of adrenal
insufficiency occurring as a result. So, for example, if you
have been giving 5 mg each day, your vet might ask you to give 2.5mg daily
for two weeks, then 2.5mg every other day for two weeks, then 1.25mg every
other day for two weeks, and so on. Your vet will advise you on the best
way to taper your cat's dose.
Mar Vista Vetdiscusses the
potential problems of ongoing corticosteroid use.
Steroid
treatment - effectsincats
(2009) Hunter T & Ward E VCA Animal Hospitals discusses the short and long term effects of using corticosteroids.
Glucocorticoid use in cats
(2010) Lowe A Veterinary Medicine pp56-62 discusses the pros
and cons of using corticosteroids.
Corticosteroids and Congestive Heart
Failure
If your cat develops
congestive heart
failure (CHF) within a week of starting corticosteroids, the steroids
may be the cause.
Corticosteroid-associated congestive heart failure in
12 cats (2004) Smith SA, Tobias AH,
Fine DM, Jacob KA, Ployngam T The International Journal of Applied
Research in Veterinary Medicine2(3) pp159-170 found that some
cats developed a unique form of CHF within seven days of starting steroids. Five of the cats
died, but once taken off the steroids the seven that survived did much
better than the typical CHF patient.
Anabolic steroids can help build up muscle, and thus have their place in the
treatment of CKD cats with muscle wasting; they may also be beneficial as
an appetite stimulant and are sometimes used for mild
anaemia.
Your vet may prescribe anabolic steroids in the form of
either tablets or injections. A commonly used anabolic steroid in Europe
is
Laurabolin.
Stanozolol
(Winstrol-V) was popular in the US
but
it appears to have been unavailable since September 2004, which apparently
is related to some type of FDA regulation. It may still be obtainable from
some compounding pharmacies.
warns that Winstrol-V may
cause severe liver disease in cats. In Medical management of chronic kidney disease in cats
(2015) Dr S DiBartola says "The use of anabolic
steroids (e.g., stanozolol) in CKD is empirical and their efficacy remains
to be documented. The margin of safety for the commonly used anabolic
steroid, stanozolol in cats is narrower than in dogs and it may result in
hepatotoxicity characterized by hepatic lipidosis and cholestasis with
minimal hepatocellular necrosis. Thus, use of anabolic steroids in cats with
CKD is not recommended."
Thomas took anabolic steroids whilst he had
CKD. He received a monthly shot at the vet's. We were able to reduce
Thomas's steroid dose, but he still seemed to do better overall when he was
taking his anabolic steroids.
adult (somatic) stem cells, which are
found within the body, particularly in the bone marrow and within
adipose tissue (fat).
There are ethical concerns regarding the use of
embryonic stem cells, but the stem cell transplants discussed below use
adult stem cells.
Stem Cell Transplant Benefits: General
Adult stem cells can help the body to repair
itself. One type, mesenchymal stem cells (MSCs),
help to produce bone, cartilage and cells that assist with the creation
of fibrous connective tissue, so they can be useful for treating joint
problems.
They have been widely used to treat arthritis in dogs and tendonitis in
horses.
Trials are currently under way into the use of stem cell therapy in cats
with stomatitis, a chronic oral condition.
Business Insider reports further on
this.
Stem cell therapy also appears to be helpful for cats with Inflammatory
Bowel Disease.
A number of studies have shown that stem cell transplants may improve
kidney function, prevent scarring and improve proteinuria
(excess protein in the urine) in rats.
A 2004 study
demonstrated that adult stem cells may also assist with repairing damaged
kidneys in mice. Adult stem cells were taken from the muscle tissue of
healthy mice and cultured. Following implantation into mice with damaged
kidneys, the cells formed new blood vessels and appeared to improve kidney
function.
This may be because mesenchymal stem cells can travel to affected areas
of the body and help other stem cells to grow, encouraging healing.
Therefore, some US vet schools have been
studying the use of stem cells to help cats with CKD (see
below).
A number of cats have received stem cell treatments
at Colorado State University College of Veterinary Medicine and at the Animal Medical Center in New York City,
though neither is currently looking for new participants.
Pet Placehas an
overview of stem cell therapy in cats.
If the stem cells come from the cat's own body,
they are known as autologous stem cells.
If they come from another source, they are known
as allogeneic stem cells.
Novel treatment strategies for feline chronic kidney
disease: a critical look at the potential of mesenchymal stem cell therapy
(2015) Quimby JM & Dow SW The Veterinary Journal 204(3)
pp241-246 does mentions that one study found that allogeneic MSCs were
less effective than autologous MSCs in rats with AKI, but points out the
"advantages of using allogeneic MSCs include sparing the patient from
undergoing the harvest procedure as well as the use of MSCs from young
healthy donor animals. Recent studies in humans and rodents support the
view that MSCs obtained from young healthy individuals have greater
proliferation potential and have greater therapeutic potential than
those collected from elderly diseased individuals."
This paper also makes the important point that "Another concern
about autologous MSC administration in animals with kidney disease is
the growing body of literature supporting the theory that MSCs are
adversely affected by
uremia. Recent studies have documented that MSCs
obtained from uremic rats have reduced proliferation in culture, caused
loss of regenerative potential, premature senescence, decreased capacity
to induce angiogenesis, and an altered secretome."
A later study in cats,
Comparison of proliferative and immunomodulatory
potential of adipose-derived mesenchymal stem cells from young and
geriatric cats (2017) Zajic LB, Webb TL, Webb P, Coy JW, Dow
SW, Quimby JM Journal of Feline Medicine & Surgery19(10)
pp1096-1002, found that it took longer to grow the stem cells from older cats
with CKD or cancer (9-22 days) compared to healthy younger cats (6-8
days), but "once the cells are expanded, young and geriatric cat aMSC
appear to be equivalent in terms of their ability to functionally
suppress T-cell activation and proliferation." Nevertheless, it may not
be possible to produce enough stem cells quickly enough in older cats,
especially those with CKD.
There have been a number of studies performed in the USA into the use of
stem cell transplants in CKD cats. Many of these have taken place at the
Veterinary Teaching Hospital at Colorado State
University, in cats with stable chronic kidney disease (creatinine
2.0 to 5.0 mg/dl), though they are
not currently looking for new participants. Exclusion criteria included heart disease, kidney
infection, stones in the ureter or other renal complications.
Evaluation of intrarenal mesenchymal stem cell
injection for treatment of chronic renal disease in cats: a pilot study
(2011) Quimby JM, Gibbons DS & Dow SW Journal of Feline
Medicine & Surgery13(6) pp418-26 reports on the pilot
study.
A member of
Tanya's CKD Support Group enrolled the
first cat in this study in February 2009, and she told me that the
initial cost (for tests and visits) was in the region of US$600,
although she was given a lot of free therapeutic kidney food. Her cat had stem
cells injected into one kidney initially, and she said he was a little
quiet immediately afterwards, which she thinks might have been caused by
the mild anaesthesia he was given, but he seemed OK otherwise. After one
month, it appeared his kidney function had improved by approximately 15%
according to a
scintigraphy scan which checks
glomerular
filtration rate (not every cat would undergo this, he did so because
he was the first participant). His creatinine fell from 6 to 5.2 mg/dl and his
BUN from 80 to 66 mg/dl. Sadly, her cat had
kidney stones
before he took part in the study, and he died in June 2009, probably
because of the complications caused by the kidney stones. Cats with
kidney stones became ineligible for the study.
In this study, the stem cells were autologous stem cells (see
above) administered
intrarenally. The study concludes "Despite the possible benefits of
intrarenal MSC injections for CKD cats, the number of sedations and
interventions required to implement this approach would likely preclude
widespread clinical application. We concluded that MSC could be
transferred safely by ultrasound-guided intrarenal injection in cats,
but that alternative sources and routes of MSC therapy should be
investigated."
Safety and efficacy of intravenous infusion of
allogeneic cryopreserved mesenchymal stem cells for treatment of chronic
kidney disease in cats: results of three sequential pilot studies
(2013) Quimby JM, Webb TL, Habenicht LM & Dow SW Stem Cell
Research & Therapy4(2) reports on three further studies (numbers 1,
2 and 3) conducted at Colorado State University in which the stem cells
were administered intravenously.
CSU had found that it can be difficult to grow stem cells from older
cats, which CKD cats often are, so they obtained and grew stem cells
from the fat of young healthy cats (allogeneic) and these cells were given
to CKD cats as an
intravenous (IV) injection. The stem cell therapy was given once
every two weeks for three treatments, and then monthly for three
treatments if improvement was seen. At each visit, bloodwork was
performed and an IV catheter placed to administer the stem cell
treatment.
Cats in
study 1 had no adverse side effects.
Study 2 found that of the five cats in the study, side effects of
vomiting (two cats) and increased respiration (four cats, one severe)
were seen. This study used the same sort of cells but cells were taken
directly from cryopreservation and higher doses were used than in the
other two studies. Study 3 did not see any side effects, and the report
states "Thus, we have concluded that the administration of a higher dose
of aMSCs taken directly from cryopreservation, despite careful washing,
was the source of the toxic reactions observed, and this form of
administration is not recommended."
Unfortunately, although 40% of the cats in studies 1 and 2 showed an
improved
glomerular
filtration rate, the researchers felt that overall the improvement was modest.
The paper concludes "Administration of cryopreserved aMSCs was
associated with significant adverse effects and no discernible
clinically relevant improvement in renal functional parameters.
Administration of aMSCs cultured from cryopreserved adipose was not
associated with adverse effects, but was also not associated with
improvement in renal functional parameters."
Assessment of intravenous adipose-derived
allogeneic mesenchymal stem cells for the treatment of feline chronic
kidney disease: A randomized, placebocontrolled clinical trial in eight
cats (2016) Quimby
JM, Webb TL, Randall E, Marolf A, Valdes-Martinez A & Dow SW Journal
of Feline Medicine and Surgery18(2) pp165-171 concluded "No
significant change in serum creatinine, BUN, potassium, phosphorus, GFR,
UPC, or packed cell volume was observed in cats treated with MSCs. While
administration of MSCs culture-expanded from cryopreserved adipose was
not associated with adverse effects, significant improvement in renal
function was not observed in the weeks following administration.
Long-term follow up of cats participating in all clinical trials is
still under way and will provide additional information about the
effects of MSC therapy on disease progression."
The Animal Medical Center
in New York conducted research into stem cell therapy in CKD
cats via intra-arterial administration because it was
thought more of the stem cells reach the kidneys with this method.
Intra-arterial delivery of mesenchymal stem cells in
veterinary patients (2012)
Berent A Presentation to the Advanced
Renal Therapies Symposium, NYC, discusses their research (page 49).
Mesenchymal stem cell therapy in cats: current
knowledge and future potential (2018) Quimby JM & Borjesson DL
Journal of Feline Medicine and Surgery20(3) pp208-216 says
'None of the studies conducted on cats with CKD have been able to
replicate the efficacy of MSC treatment reported in rodent models of
experimentally induced CKD or AKI... At this time, MSC therapy for CKD
in cats should be considered an experimental and unproven therapy."
How Stem Cell Transplants are
Performed
In vitro comparison of feline bone marrow-derived and adipose
tissue-derived mesenchymal stem cells
(2012) Webb TL, Quimby JM & Dow SW Journal of Feline Medicine
and Surgery14(2) pp 165-168 found that not only is it
usually easier to obtain feline stem cells from adipose tissue (fat),
but the stem cells obtained are usually more proliferative too, so
obtaining stem cells from fat is the preferred choice for cats.
Whichever way the stem cells are obtained, unfortunately
anaesthesia is
usually necessary
(VivaStem's stem cell fluid treatment does not require anaesthesia), which is not ideal for CKD cats,
but for most cats it will be day surgery and they will be able to return home
in the evening of the procedure.
The vet makes a small incision in the abdomen, groin or behind the
shoulder blade and extracts some fat. The vet removes stem cells from
the fat, then transplants them into the cat via an intravenous infusion
(drip) (the process may be slightly different in vet schools, see
below).
The extraction takes several hours, but if your vet is trained to
perform this procedure in-house, the transplant can normally be
completed within a day. Otherwise your cat will normally have to return
two days later to have the stem cells injected via an intravenous
infusion, for which the cat may be under sedation.
The stem cells then travel to areas of inflammation within the body
where they help to repair damaged tissue. Spare stem cells can be stored
until they are needed. One procedure can yield up to 18-20 doses, which
could last up to two years.
There are four companies in the USA which offer stem cell treatments for
vets to use on dogs with arthritis and they will also consider assisting
with stem cell therapy for CKD cats. Vets are trained by these companies
to take stem cells from the animal, but the process thereafter depends
upon the company:
Require the fat tissue to
be sent to their own laboratory for processing, and they then return the
cells to the vet for injection into the dog (or cat).
Uses stem cell fluid rather than stem cells. It is not clear how they
collect the fluid (they say it is a "proprietary technique"), though one
member of Tanya's CKD Support Group says she was told they actually come
from horses. Because it does not contain living cells, it is much
cheaper (US$100-200), but apparently the healing proteins remain in the
body for about four months.
Stem cell transplants are not currently approved for CKD cats but
a number of vets do now offer them in the USA and the UK.
MediVet provides its product to vets in both countries. Vet-Stem is evaluating the use of its product for CKD in cats, and may agree to this treatment
being
given to a CKD cat if a vet requests it, on the basis of what it calls
"compassionate use." The conditions for doing this can be found on page
42 of
Feline kidney disease: cell therapy perspectives (2012) Harman R Presentation to the Advanced
Renal Therapies Symposium, NYC.
VivaStem will also distribute its product for CKD cats upon veterinary
request on compassionate grounds and does so at cost.
Apparently there are a couple of vets in
Australia who offer stem cell therapy, and they seem to charge a lot less. I am told the injections are given every week for three
weeks, by which time one would expect to see a difference in the cat in
terms of improved appetite and reduced vomiting. I only know of one
person to date whose CKD cat has had this treatment in Australia, she didn't think it
helped.
Stem Cell Effectiveness
In
Feline kidney disease: cell therapy perspectives (2012) Harman R Presentation to the Advanced
Renal Therapies Symposium, NYC, Dr Harman states that 25 feline CKD
cats had been treated by Vet-Stem as at February 2012, for an average
period of 776 days, with the longest case to date being 1460 days. 84% of
those treated thus far were still alive. For 14 of the cats, there was no
outcome yet, but of the 11 with an outcome, one cat did not respond to the
treatment, and another had only a mild response.
54% (seven people) felt their cat had a significant improvement in
quality of life, and a further 15% (two people) felt there had been a mild
improvement. 23% (three people) saw no change, and 8% (one person) felt
their cat was worse.
Not
everyone is so positive. Stem Cell Therapy in Emergency and Critical Care Diseases
(2015) Sharp CR
Presentation to the Australian and New Zealand College of Veterinary
Scientists Science Week 2015 says ""Unfortunately,
multiple companies saw the potential for commercial gain in this field and
started marketing veterinary “stem cell” therapies without safety or
efficacy data. Subsequent to products already being on the market, a few
studies have been done in dogs with chronic orthopedic disease, however
reading the methodology of these papers suggests that these cell therapies
should not be considered stem cells.
These commercially available “stem cell” products will not be discussed
further. Fortunately, there are multiple groups of credible investigators
evaluating the therapeutic potential of true MSCs that have published
their work in the translational and veterinary literature. Although none
of these therapies are commercially available at this time, there is most
definitely potential for a therapeutic role of such therapies in
veterinary medicine in the future."
Mesenchymal stem cell therapy in cats: current
knowledge and future potential (2018) Quimby JM & Borjesson DL
Journal of Feline Medicine and Surgery20(3) pp208-216 says
'None of the studies conducted on cats with CKD have been able to
replicate the efficacy of MSC treatment reported in rodent models of
experimentally induced CKD or AKI... At this time, MSC therapy for CKD
in cats should be considered an experimental and unproven therapy."
Stem Cell Experiences
I have heard from a number of people who have tried stem cell
transplants on their cats. Many of them felt it had made no difference,
and several felt it made their cats sick (vomiting, lethargy etc).
However, there have been a few apparent successes. One
six year old cat on Tanya's support
group had creatinine of 900 µmol/L (8.9 mg/dl) upon diagnosis, together
with severe anaemia. Her condition improved after
each stem cell treatment and eventually her creatinine stabilised at 135
µmol/L (1.5 mg/dl). The anaemia also resolved.
Another cat was diagnosed in spring 2013 at the age of five (following
suspected
lily
toxicity) with a very high creatinine level (1500 µmol/L or 17
mg/dl). His creatinine remained high (850 µmol/L or 9 mg/dl) a year
later, but following three stem cell injections (on days 1, 14 and 28)
his creatinine reduced to 340 µmol/L (3.85 mg/dl) and he lived until
Christmas 2014. His caregiver stated that she did not know if the stem
cell therapy definitely helped but it didn't seem to do any harm.
It was only possible to obtain sufficient stem cells for one stem cell
injection in another 16 year old cat, but her bloodwork remained stable for a
year following the treatment and she was acting much better.
Many cats seem to feel below par for a few days after the injections and
may vomit and not want to eat.
VetStem has a checklist
to use when considering stem cell transplants, and provides a list of
conditions that exclude a cat as a suitable candidate.
Stem Cell Cost
The cost depends to a large extent on your vet.
Most people who have the treatment performed on dogs with arthritis seem
to pay around US$2000-4000.
One member of
Tanya's CKD Support Group
was quoted US$3000 by her vet to treat her cat. She went ahead and her
cat recovered well, though he did not have it done because of CKD but
because of severe immune-mediated anaemia.
Another member was charged under US$2000 for her cat in 2015.
A British member was charged Ł2000 for a year's treatment.
Kidney Transplants
Some people are
surprised to find kidney transplants listed as a treatment, but that is
exactly what they are — a form of treatment, not a cure.
Kidney
transplants entail surgically removing a kidney under general anaesthetic from a healthy donor cat
(usually under the age of three) and
surgically transplanting it into the CKD cat.
As with human kidney transplants, the donor cat can manage with one
kidney, because of the
renal reserve, which means the cat's remaining kidney gradually takes
over the workload of the removed kidney.
With most feline kidney transplants, the caregiver of the CKD receiving
the kidney is expected to give a forever home to the donor cat.
Interestingly, the University of Georgia has
performed two successful transplants which also utilised
stem cells.
Transplants used to be available at one location in Brisbane, Australia
but they are not currently being offered.
The
Royal College of Veterinary Surgeons
issued guidelines for kidney transplants in 2003 in order to ensure the highest welfare standards for both
the recipient and the donor, but the guidelines were revised in 2016 and
state that the College "does not support the use of living source donors
for feline renal transplantation. This is contrary to a basic tenet of
veterinary practice that inflicting pain and discomfort on an animal can
only be justified as an act of veterinary surgery if it is for the benefit
of the animal receiving that pain and discomfort." Therefore transplants
are not available in the UK.
Survival Times and Potential Problems
One centre has
stated that the average survival time for a cat receiving a kidney at its
facility is only 18 months; whilst The Animal Medical Center in New York
stated that 25% of cats who underwent transplants there did not even survive
the initial operation of receiving the kidney, and only 60% survived one
year. Even at one of the most longstanding centres, The University of
California at Davis,
20-25% of cats died in the year following the transplant.
The Animal Medical Center in New York and The University of California at
Davis are not currently performing kidney transplants.
Another vet
school with extensive experience,
University of Pennsylvania College of Veterinary
Medicine, states that approximately 60-70% of recipients are
still alive after one year (so 30-40% do not survive for a year).
A kidney for kitty (2014) is an article
in
The Philadelphia Inquirer about kidney transplants at the University of
Pennsylvania School of Veterinary Medicine. It states that 92% of patients leave hospital, 70%
survive for one year and the median survival
is 1000 days.
Renal transplantation surgery, anesthesia and survival times
(2015) Snell W, Aronson L, Phillips H, Beale L & Larenza Menzies MP
Journal of the American Veterinary Medical Association247(3) pp267-277
examined the records of 94 cats who underwent kidney transplant and found
that
"median survival time for the cats in this study was 653 days. The
proportion of cats that survived 30 days was 84%, 6 months (76%) and 3
years (30%)...Cats that were 12 years of age and older that underwent RTS
had a decreased overall survival time compared to younger cats."
Retroperitoneal fibrosis in feline renal transplant
recipients: 29 cases (2013)
Wormser C, Phillips H & Aronson LR Journal of the American Veterinary
Medical Association243(11) pp1580-1585 found that 21% of the
cats in this review who had received kidney transplants developed renal
fibrosis, which caused lethargy, anorexia, elevated kidney values and
anaemia. Most of them were able to have the scar tissue successfully
removed surgically, but the problem recurred in six of the cats.
Problems arise for a number of reasons. Firstly, this is major surgery,
and by definition it is being performed on seriously ill cats. The Snell study above found
that the length of time the cat was under anaesthesia appeared to be a
factor in length of survival post-surgery. It also found "All the cats
receiving m-opioid receptor antagonists reached the 30-day survival point
and the significance of this factor was considered due to the prevention
of opioid-induced cardiorespiratory depression post-anesthesia.
Maintaining an adequate hematocrit post-surgery also improves the odds of
cats surviving for at least 30 days."
Secondly,
immunosuppressive drugs (usually cyclosporine), which stop the body
rejecting the new kidney as a foreign body, are required. These must be
given religiously at set times (usually every twelve hours), but even so,
they may not work for every cat, and then the new kidney is rejected by
the cat's body and ceases to work. Since these drugs suppress the immune
system, transplant recipients are also vulnerable to infections, which may
damage the new kidney.
Unfortunately
these anti-rejection medications also increase the chances of the cat
developing cancer, with a 14% incidence rate reported in cats at one
facility who survived more than one year after the transplant. 10% of
feline kidney transplant recipients
also develop diabetes.
Because of the
foregoing, as The University of California at Davis has stated, "Due to all the inherent risks with transplantation, it is not
considered a prophylactic procedure, and those cats that are doing well
with medical management are not considered candidates for
transplantation."
Having said that, one cat who received a kidney transplant at the
University of Pennsylvania College of Veterinary Medicine managed thirteen years and
counting, whilst the University of Wisconsin School of Veterinary
Medicine reported that its oldest transplant recipient
reached the age of 22 in 2014, having received a kidney five years earlier
at the age of seventeen.
Their longest survivor lived for over nine years following the transplant.
Athens Banner Herald reports on two cats
who were given stem cell therapy prior to kidney transplants
in 2013 and 2014. The second cat, Arthur, was given stem cell therapy because he did not properly absorb
cyclosporine, which normally is used to reduce the risk of rejection
following a kidney transplant, and it was hoped the stem cell therapy
would reduce the risks of rejection. The procedures were successful, and the
first cat was still alive a year after the transplant. Arthur was still
alive eighteen months after his transplant according to an update in the
Daily Mail
dated November 2015.
A member of Tanya's CKD Support Group's cat had a kidney transplant in
April 2017 following five sessions of
dialysis.
The surgery went well but I have not heard any more. Another member's cat
received a transplant in June 2018, and in March 2019 he was still alive
and doing very well. He had developed diabetes as a side effect of one of
his post-transplant medications but it was successfully brought under
control.
Hobbes' story
tells of one cat's experience of a kidney transplant where the surgery
went well but the cat's body rejected the kidney a few months later.
Transplant
Cost
Transplants are extremely expensive.
University of Pennsylvania School of Veterinary
Medicine gives the cost of
the initial transplant as US$18000 - 20000 plus ongoing maintenance costs.
A kidney for kitty (2014) is an article
in
The Philadelphia Inquirer about kidney transplants at the University of
Pennsylvania School of Veterinary Medicine. It states that a transplant
costs US$18-24000.
The Atlantic
(2022) reports on a cat called Strawberry who had a transplant at the
University of Georgia for US$15000.
University of Wisconsin-Madison School of Veterinary
Medicine does not give prices online, but states that the
annual drugs cost is US$500-1500. In
2014 one member of Tanya's CKD Support
Group was quoted US$1500 for pre-transplant testing, US$5000-8000 for the
transplant, and US$3000 per year for post-transplant medications.
American Animal Hospital Association
states that following transplantation you will need to spend $60-100 a
month on medications including anti-rejection medications. You will
also have to budget for frequent vet visits to check all is well.
Ethical Considerations
The major UK charities, Cats
Protection, the RSPCA and International Cat Care, are opposed to
kidney transplants because of the ethical issue of removing a kidney from
a healthy donor cat with no benefit to that cat.
In the USA it
is often argued that using a shelter cat "saves a life"; but in the UK,
very few cats are euthanised compared to the millions in the USA. In any
event, all the US transplants I heard about
in the late nineties and early noughties used
a cat purpose-bred by the transplant facility as a donor, so no shelter
cats were saved. Recent transplants at the University of
Pennsylvania School of Veterinary Medicine have used shelter cats, but the
websites of the two other vet schools which perform transplants are very
vague about where and how they "source" the donor cats.
The
Royal College of Veterinary Surgeons
issued guidelines for kidney transplants in 2003 in order to ensure the highest welfare standards for both
the recipient and the donor, but the guidelines were revised in 2016 and
state that the College "does not support the use of living source donors
for feline renal transplantation. This is contrary to a basic tenet of
veterinary practice that inflicting pain and discomfort on an animal can
only be justified as an act of veterinary surgery if it is for the benefit
of the animal receiving that pain and discomfort." Therefore transplants
are not available in the UK.
I have often wondered what would happen should the donor cat develop
CKD
him/herself later in life; presumably such a cat, with only one
functioning kidney, would develop end stage renal failure more quickly
than a cat with two kidneys. Indeed, Challenges of feline renal transplant (2010) Gunew M Presentation to the Australian College of
Veterinary Scientists College Week states "The effects of unilateral nephrectomy seem to be a slightly reduced
life expectancy."
Perioperative morbidity and long-term outcome of
unilateral nephrectomy in feline kidney donors: 141 cases (1998-2013)
(2016) Wormser C & Aronson LR Journal of the American Veterinary
Medical Association 248(3) pp275-281 looked at 141 donors who
were all two years old or younger at the time of donation. Long term
follow up data were available for 99 cats. The study concludes "Most cats
(84%) for which follow-up information was available had no associated
long-term effects. However, a small subset (7%) developed renal
insufficiency or died of urinary tract disease."
Both Cats
Protection and the RSPCA have stated that they will not supply cats as
donors, and Cats Protection have gone so far as to state that they would
"support rigorous punishment measures for any individual who acquires a
cat, through whatever means, to use as a donor for feline kidney
transplantation".
TREATING YOUR CAT WITHOUT VETERINARY ADVICE CAN BE
EXTREMELY DANGEROUS.
I have
tried very hard to ensure that the information provided in this website is
accurate, but I am NOT a vet, just an ordinary person who has lived
through CKD with three cats. This website is for educational purposes
only, and is not intended to be used to diagnose or treat any cat. Before
trying any of the treatments described herein, you MUST consult a
qualified veterinarian and obtain professional advice on the correct
regimen for your cat and his or her particular requirements; and you
should only use any treatments described here with the full knowledge and
approval of your vet. No responsibility can be accepted.
If your cat
appears to be in pain or distress, do not waste time on the internet,
contact your vet immediately.
This site was
created using Microsoft software, and therefore it is best viewed in
Internet Explorer. I know it doesn't always display too well in other
browsers, but I'm not an IT expert so I'm afraid I don't know how to
change that. I would love it to display perfectly everywhere, but my focus
is on making the information available. When I get time, I'll try to
improve how it displays in other browsers.
This site is a labour of love, from which I do not make
a penny. Please do not steal from me by taking credit for my work.
If you wish to
link to this site, please feel free to do so. Please make it clear that
this is a link and not your own work. I would appreciate being informed of
your link.