Complete Care for Your Aging Cat
Page 30
help quickly.
A new blood test for Daffy came back okay except for the
kidney values. In less than seven months, the cat’s BUN
(blood urea nitrogen value) jumped from normal to 51, and
creatinine to 3.4—wel over the normal range. “Things can
change very quickly with cats, and overnight something wil
crop up,” she says.
The veterinarian suggested dietary changes, and gave
Daffy beneath-the-skin fluids for her dehydration. “They
asked me to bring her back in two days for more fluids,” says
Chris, an experienced home-care owner. She compares
nursing care to addressing the needs of any aging family
member, and she had no hesitation about giving Daffy 100
mil iliters of fluids every other day.
When she returned for a fol ow up visit, Chris shared her
concern that Daffy had started throwing up her food, and was
stil lethargic. Blood values were reduced, though, and an X-
ray showed nothing unusual. Once Daffy had eaten the
special diet for a couple of days and received additional
fluids, she began to improve. A week later, Daffy’s blood test
revealed how wel the special diet and fluid therapy were
working when BUN and creatinine values dropped into the
normal range. “I’m continuing to give her fluids every other
day.”
Several years ago when she had been first faced with
giving subcutaneous fluids to a cat, Chris had a lot of
hesitation. She wondered if being poked with a needle
would be bad for quality of life. “But I see the difference when
they have those fluids, and how much better they feel,” says
Chris. “There’s no question in my mind that this is good for
them. If I can al eviate their discomfort, that’s what I’l do,
even if makes my life difficult for a while.” She accepts that
as part of the responsibility of loving pets.
Being in the home environment reduces their stress level
and can be therapeutic. Chris established a routine that
makes the operation comfortable for the cat and the people
involved. “This is the third cat I’ve done this. I’ve learned it’s
easier if someone holds and talks to the cat.” So Daffy has a
treatment team—Chris and her 12-year-old daughter
Michel e.
“Michel e real y does a great job. She holds her front end
while I kind of sit behind Daffy, pul the skin up to make a little
tent, and insert the needle at the base of the tent, paral el to
the body. Then I let it relax and turn on the fluids,” says Chris.
In the meantime, Daffy’s doing wel . Chris considers the
process of home care to be a loving way to cherish every
moment with the aged cat. “Treating Daffy has given my
daughter an opportunity to feel like she’s doing something to
help,” says Chris. “With al of my animals I truly feel blessed
that they were a part of my life. Maybe that sounds corny,”
she says, “but they just bring us so much and ask for so
little…”
Hemodialysis
In human renal failure, the standard medical treatment is
dialysis in which a machine takes the place of the damaged
kidneys, and cleanses the blood of the toxins. The first
program for pets was launched in 1998 at University of
California-Davis. “We use neonatal equipment, and we can
accommodate dogs and cats as smal as two kilograms,”
says Larry Cowgil , DVM, head of the companion animal
hemodialysis unit at University of California-Davis, and
founder of the program.
Hemodialysis is used primarily for acute kidney failure,
designed to give the organs the time to heal the damage.
“Usual y an animal wil die of acute kidney failure in four to
five days, but it may take weeks or even months for the
kidney to get resolved,” says Dr. Cowgil . Cats with chronic
kidney failure usual y are not good candidates for dialysis,
because the process is so expensive, and they would need
treatment for the rest of their lives.
Hemodialysis is often used before, during and/or after a
feline kidney transplant until the new organ starts to work.
“Many pet owners today are wil ing to use their discretionary
money to bear that cost if in fact there’s some expectation
the animal’s going to recover,” says Dr. Cowgil . “We
probably dialyze 50 percent of the animals we transplant.”
The school handles up to 400 treatments each year.
Hemodialysis units for pets are only available in a
handful of places:
The Animal Medical Center
510 E. 62nd St.
New York, N.Y. 10021
(212)
838-8100,
begin_of_the_skype_highlighting(212)
838-
8100 end_of_the_skype_highlighting
Tufts Foster Hospital for Small Animals
200 Westboro Road
North Grafton, MA 01536
(508)
839-5302,
begin_of_the_skype_highlighting(508)
839-
5302 end_of_the_skype_highlighti
University of California Veterinary Medical Teaching Hospital
Companion Animal Hemodialysis Unit
1 Garrod Dr.
Davis, CA 95616
(530)
752-1393,
begin_of_the_skype_highlighting(530)
752-
1393 end_of_the_skype_highlighting
UC Veterinary Medical Center-San Diego
10435 Sorrento Valley Rd, Suite 101
San Diego, CA 92121
phone:
(858)875-7505,
begin_of_the_skype_highlight(858)875-
7505 end_of_the_skype_highlighting
fax: (858)875-7583
http://www.ucvmc-sd.vetmed.ucdavis.edu/default.cfm
e-mail: sdhemodialysis@vmth.ucdavis.edu
Veterinary Hospital of the University of Pennsylvania Hemodialysis Center
Matthew J. Ryan Veterinary Hospital
3900 Delancey St.
University of Pennsylvania
Philadelphia, PA 19104
(215)
898-4680,
begin_of_the_skype_highlighting(215)
898-
4680 end_of_the_skype_highlighting
School of Veterinary Medicine
Louisiana State University
Baton Rouge, LA 70803-8410
(225)578-9600,
begin_of_the_skype_highlighti
(225)
578-
9600 end_of_the_skype_highlighting
University of Florida, VMTH
2015 SW 16th Avenue
Gainesville, FL 32610
(352)392-2235,
begin_of_the_skype_highlightin(352)392-2235,
end_of_the_skype_highlighting ask for hemodialysis coordinator
fax: (352)846-2445 attn: hemodialysis coordinator
Transplants
Dr. McAnulty began transplanting pet kidneys in 1995.
Cats are fortunate in that their bodies wil accept the healthy
kidney of any other cat with few rejection problems. Different
transplant programs obtain donor cats from different
sources. Dr. McAnulty gets donor cats from commercial
laboratories and from a private local shelter.
Since healthy cats need only
one kidney to live long,
healthy lives, no cat is sacrificed so another can live. In fact,
the owner of the recipient cat adopts the donor cat. That
means a happy ending for al concerned. “The owners who
do this are true cat lovers,” says Dr. McAnulty. “Everyone has
been very happy with the donor cats in their household.”
Candidates for a kidney transplant must be otherwise
healthy to be considered for the program. “But we don’t
discriminate based on age,” he says. Most are seven- to
nine-year old range, but the oldest cat to date has been 16,
and one was less than a year old. “If they’re old and look
fairly robust, and they’re healthy, then it’s a reasonable thing
to do.”
Anti-rejection drugs such as cyclosporine work wel in
cats. However, surgery is expensive, and anti-rejection
medication wil be needed for the rest of the cat’s life. “I’ve
found our clients are very good at it,” says Dr. McAnulty. But
if the struggle of forcing pil s into your cat destroys his quality
of life, a kidney transplant may not be worthwhile for him.
Kidney transplants are available at only a handful of
veterinary centers around the country. University of
California-Davis began the first program but it is currently on
hold. Another established program is at the University of
Pennsylvania. A list of facilities currently performing the
surgery
is
available
at
the
excel ent
website
http://www.felinecrf.com/transb.htm.
Bottom Line
“The typical cost for hemodialysis here is about $300
to $400 per treatment,” says Dr. Cowgil . During the
course of treatment that can easily run to $5,000 to
$7,000.
Kidney transplant starts at about $6,000 at the
University of Wisconsin, and anti-rejection medicines
fol owing surgery typical y cost about $1,500 per year
for maintenance, says Dr. McAnulty. Costs vary at
other programs.
LIVER DISEASE
The liver has multiple functions, from screening out toxins
and metabolizing drugs, to creating necessary nutrients and
enzymes. Liver disease can be any condition that interferes
with one or more of these processes, and it may develop at
any age.
Fortunately, the liver has quite a bit of built-in redundancy,
and only a smal portion of the organ needs to function to
maintain the cat’s health. “After some insults, it’s ful y
capable of regenerating to its original size,” says Cynthia R.
Leveil e-Webster, DVM, an internist at Tufts University. A
lifetime of exposure to toxins, stress, and damage means
old cats are more prone to liver problems. Some diseases
damage the liver so badly it isn’t able to recover.
Hepatic lipidosis is the most common liver disease of
cats, and cholangiohepatitis is the second most common,
says Dr. Davenport. “Occasional y you see cats that have
both diseases simultaneously.”
Dr. Schulman says it’s a myth that only obese cats get
hepatic lipidosis. Once the cat stops eating, fat is released
into the blood as a source of nutrition. Because the liver cel s
store fat, they quickly become overwhelmed and are no
longer able to function. “About ten years ago, the disease
was invariably fatal because doctors did not know how to
treat it. These days, most cases survive,” says Dr. Schulman.
There are also three forms of inflammatory liver disease
(hepatitis) that affect cats. The acute form is usual y caused
by bacterial infection, says Dr. Webster. The two others are
so similar they can only be told apart by examining cel s
under the microscope. One tends to be a disease of young
to middle aged cats. Lipacidic hepatitis, or lipacidic
cholangiohepatitis most commonly affects aged cats, says
Dr. Webster. Some studies indicate that even when they
don’t become sick from it, many old cats have this mild to
moderate inflammation in their livers. “My own cat has it,”
she says. “It’s rare that it requires intervention and therapy.”
Signs can be confusing because liver disease mimics
other il nesses, and often the sick cat has problems in other
body systems at the same time with symptoms that overlap.
“Cats that have liver disease can actual y get concurrent
diseases of their intestinal tract and pancreas,” says Dr.
Webster. “It’s cal ed triaditis, and means al three are
inflamed at once.”
Senior Symptoms
Signs of liver problems are similar and quite vague,
whatever the type of disease.
Jaundice—yel owish tinge to the gums, whites of eyes,
or inside of ears
Refusal to eat
Vomiting
Weight loss
Increased drinking and urination
Lethargy
Neurological signs including confusion or dul ness
Diagnosis
Signs of liver disease are so vague it requires
sophisticated tests to diagnose. “The owners sometimes
notice they turn yel ow,” says Dr. Webster, but that happens
most often with advanced cases. Bile produced by the liver
aids in the digestion of fat, and it can turn the cat’s skin
yel ow when it backs up in the blood circulation.
Also, increased pressure on the veins entering the liver
can prompt an accumulation of fluid (ascites) causing the
abdomen to swel , but that’s a rare finding in cats and much
more common dog. Another rare consequence of liver
disease is hepatic encephalopathy that affects the brain.
“Toxins build up in the blood that the liver normal y removes.
It can go to the brain and cause confusion—they just look out
of it,” says Dr. Webster. “Occasional y they can have
seizures.”
A biochemical profile of the blood is the first step toward
diagnosis. Liver enzymes may be elevated for a number of
reasons, though, and elevated enzyme values does not
automatical y mean the cat has liver disease. “Probably the
number one reason for a high liver enzyme in an old cat is
thyroid disease,” says Dr. Webster. “You have to go further
into diagnostic testing. Sometimes you get a picture of the
liver with the ultrasound, then get a biopsy.”
Blood tests, imaging techniques and symptoms can point
to liver disease. But a definitive diagnosis can only be made
examining tissue beneath the microscope. An ultrasound-
guided needle al ows cel s to be col ected through the
abdominal wal , often without invasive surgery.
Treatment
Treatment depends on the cause of the problem and
how early it’s caught. Once the liver scars from the
inflammation, the damage is hard to reverse. Inflammation of
the liver—the various hepatitis diseases—is treated with
drugs to suppress the inflammation. Of course, the liver
processes many drugs, yet is compromised. So when drug
therapy is n
eeded in these cats, veterinarians try to select
drugs that rely primarily on the kidneys to process.
“If I diagnose lipacidic hepatitis in an older cat, I tend to
use prednisone,” says Dr. Webster. This is not a cure, but
cats do improve with this therapy and they don’t have a lot of
side effects from prednisone the way dogs do. A rare
complication of using prednisone would be development of
diabetes.
Dr. Webster also likes to use SAMe in cats. “I’ve had a
couple cats using these long term. My cat has been on those
medications now for four and a half years and she’s doing
pretty wel .” The nutraceutical SAMe (S-Adenosylmethionine)
increases antioxidant levels in liver cel s to protect them from
toxins and death. An oral medication, brand name Actigal or
Ursodiol, is a natural y occurring bile acid that also can help
protect the liver from further damage.
Silymarin (milk thistle), and its active component
silybin are anti-hepatotoxic flavonolignans. They also have
been administered to animals with hepatotoxic drug injury.
Whether or not silymarin wil help an animal with chronic liver
disease has not been determined. The oral absorption of
silymarin from available formulations has not been
established, but this may be an avenue your veterinarian
wishes to pursue. A new compound Denamarin™ is
available containing SAMe and silibinin-phosphatidylcholine
and is available in a chewable formulation.
Vitamin therapy may also benefit cats with liver
disease, according to David C. Twedt, DVM, an internist at
Colorado State University. Dietary supplementation with
vitamin E reduces oxidant injury to hepatic tissue. Vitamin E
is recommended at a dose of 10 IU/kg/day, and the natural
form (d-Alphatocopherol) is more helpful than synthetic
forms. Vitamin K stores in the liver can become depleted
with advanced liver disease, so supplementation helps
counter this loss. B vitamins may become deficient in cats
with liver disease, and because they are water-soluble and
relatively nontoxic, supplementation using a B-complex
formulation is recommended. Cats with liver disease are
particularly prone to vitamin B12 (cobalamin) deficiency.
The recommended dose of cobalamin for cats is 250 μg
given subcutaneously weekly until normal cobalamin
concentrations are maintained.
In a study where carnitine was given to obese cats