| The following is the FUS entry from "Cat Owner's Home Veterinary Handbook"
by Delbert G. Carlson DVM and James M. Griffin. (This is an excellent book
by the way. I'll put in a separate review Real Soon Now.)
Feline Urologic Syndrome (FUS)
This is the most common disorder affecting the lower urinary tract
in male cats. It is by far the major health concern of cat owners despite
the fact to affects only 1% of all cats. One reason for this is that FUS
has a 50 to 70 per cent rate of recurrence.
FUS, also called the "blocked cat", or "plugged penis" syndrome,
can include any or all of the following: (1) cystitis; (2) urethritis;
(3) urethral plugs containing little mineral content; and (4) urinary stones.
Young inactive males are most often affected. The disease is most common
in the winter months.
FUS is caused by plugging of the urethra by a paste-like, gritty,
or sandy material, composed primarily of mucus and struvite crystals
(magnesium-ammonium-phospate) which are about the size of salt. The chief
signs of FUS are frequent voiding, straining with partial or complete urethral
obstruction, and the passage of blood in the urine.
Straining to urinate could be mistaken for constipation. However,
the behavior of the cat makes the difference obvious. [The difference is
remarkably obvious.-tlh] A cat who is unable to pass urine wanders about
the house restlessly, turns and licks at his penis, and often attempts
to pass urine in places other than his litter box. Instead of squatting
close to the ground in the usual fashion, he often adopts a characteristic
attitude in which he attempts to void from a standing position.
Major obstructions can occur with the first episode or during
subsequent attacks. With back pressure on the kidneys, toxic wastes build
up in the bloodstream, leading to uremia. [kidney failure. BTW symptoms
of kidney failure don't show until 70% of the nephrons have been destroyed.
Thus,a considerable amount of damage can occur to the kidneys before you
see the signs.-tlh] Loss of functioning kidney tissue could be irreversible.
Thus, it is of vital importance to relive the obstruction as soon as this
condition is suspected. Keep in mid that cats will often seek seclusion
when ill or in pain. Therefore, a cat with an obstructed bladder should
no be allowed outdoors.
CAUSES OF FUS:
The exact cause of FUS is unknown. A number of theories have been
advanced:
1.Three viruses have been isolated and found experimentally to produce
symptoms of the disease in some cats. Not all investigators have been able
to confirm these findings.
2.Castration of the male has been advanced as a cause. Early
castration, before sexual maturity, is believed to interfere with growth
of the adult male urethra. One survey revealed no difference in the size
of the penile urethra among castrated and non-castrated males.
3.Bacterial cystitis and urethritis have long been accepted as a
basic cause. Current research indicates that bacteria are not involved
in most cases, at least not initially. However, bacterial cystitis may
be a very important cause of recurrent attacks. Keep in mind that the
potential for infection increases with obstruction.
4.Urinary sediment has received a great deal of attention. Struvite
crystal constitute a major part of some plugs; but other crystals are sometime
found. Some plugs are composed primarily of mucus, blood and white cells.
FUS has been produced by feeding high levels of magnesium and phosphorous.
However, the amounts are many times those found in commercial cat foods.
On the other hand, in one study taking just those cats who had had
at least one episode of FUS, feeding a diet low in magnesium led to a
significant reduction in the recurrence rate.
5.The acidity of the urine is another consideration. Struvite crystals
form more readily in an alkaline urine. Acid urine is theoretically
protective,and also has antibacterial properties. However, many cases of
FUS occur in cats with acid urine.
6.Diet and water intake have been proposed as contributing factors.
Cats who eat dry food take in less water with their meals, and also lose
more water in their stools. Presumably dry cat food leads to a more
concentrated urine and a greater amount of sediment. Another theory is that
twice as much dry food is needed to meet caloric requirements, therefore
twice as much magnesium is taken in each day.
In summary, no one theory accounts for all cases. It seems likely
that any inflammatory condition of the lower urinary tract is partially
obstructive in male cats. Therefore, viruses, bacteria,urinary retention,
reduced water intake, dietary administration of sediment precursors [magnesium
-tlh], and perhaps other factors could all be contributory. The higher
incidence among inactive males in winter could be due to decreased water
intake, reduced frequency of urination, increased concentration of urine
and the subsequent higher rates of sediment formation.
As a result of one or more bouts of FUS. some cats develop scarring
which narrows their urethra. This predisposes them to further attacks,
and to bacterial cystitis.
Treatment of FUS
A cat with a plugged penis is in need of immediate veterinary
attention. An obstructed Male often protrudes his penis. You can massage
the penis by rolling it between your thumb and index finger. This might
crush the plug and allow the material to be expelled. If this is not
successful, immediate veterinary attention is required. in most cases a
small soft rubber or flexible polyethylene catheter can be inserted through
the urethra into the bladder to relieve the obstruction, usually under sedation
or anesthesia. Intravenous fluids are frequently given to rehydrate the
cat and encourage flow the flow of urine. Antibiotics are prescribed to
prevent to treat an associated bladder infection.
Prevention
Recurrent attacks are common. This suggests that (a) the initial
attack produced scarring which potentiates further attacks; or (b) factors
which caused the attack have not been corrected. The following steps should
be taken to eliminate excessive urinary sediment and/or infection:
1. Keep the litter box clean. It should be changed every day.
Some cats refuse to use a dirty box. This could result in voluntary retention.
2. Encourage water consumption by keeping clean fresh water available
at all times.
3. Feed a restricted magnesium diet. Based on currently available
research data, the optimum dietary magnesium level for prevention of recurrence
of FUS is less than 0.1% dry weight basis (DWB). Few commercial cat foods
meet these requirements. Hill's C/D is a prescription diet low in sediment
precursors and high in water content. It is available from veterinarians.
[And it costs an arm and a leg! -tlh]
4. Prevent obesity. Maintain normal body weight by restricting food
intake as discussed in the chapter FEEDING AND NUTRITION.
5. If urinary tract infection is present, treat with an appropriate
antibiotic for three or more weeks. Wait one week and then reculture.
If the culture is positive, administer a second course of antibiotic. Your
veterinarian may prescribe a long-term urinary antiseptic such as Methenemine
to prevent recurrences. It is given on a daily basis.
6. The use of supplemental salt and urinary acidifiers may be
recommended in certain cases. Mix thoroughly into the daily ration 1/2
teaspoon of table salt and 1/4 teaspoon on ammonium chloride. Salt increases
water intake and therefore urinary excretion. Ammonium chloride acidifies
the urine, which increases the solubility of struvite crystals. (CAUTION:
avoid urinary acidifiers if the cat is uremic. This could predispose to
the development of an acid-base imbalance and lead to uremic crisis.)
Cats with repeated attacks who fail to respond to the preventative
measures listed above should undergo a complete urologic work-up, searching
for bladder stones of other abnormalities in the urinary tract. In some
cases no correctable condition is found. In such cases your veterinarian
may suggest an operation in which part of the penis is removed to enlarge
the urethral opening. The operation is called perineal urethrostomy. It
usually quite successful, especially when FUS is complicated by an
overdistended, poorly contracting bladder. When the cat recovers, he will
still be able to control his urine and use the litter pan.
Finally, should all adult male cats be placed on a restricted diet
as a prophylactic measure to prevent FUS?
Considering that 99 percent of cats are not affected by FUS no matter
what they eat, and that there are other factors besides diet which may be
important in the etiology of this syndrome, feeding a severely restricted
magnesium diet such as Hill's C/D to all cats is probably not justified.
If you are concerned about FUS and want to do everything possible to prevent
it, you could choose to feed, as a cost effective alternative, a moderately
restricted magnesium diet such as Science Diet Feline. [Which also happens
to made by the people at Hill's BTW. -tlh]
|
| FELINE
UROLOGICAL SYNDROME
Are Nibblers More at Risk?
Report on testing program provided
by Morris Animal Foundation
How you feed your cat as well as what you feed him may influence
whether or not the animal develops fline urological syndrome, scientists
at the University of Georgia believe.
Previous studies of the unrinary problem, which can lead to death
if not treated, have implicated magnesium in the diet as one culprit. Cats
on diets low in magnesium and high in acidity, which acidifies the urine,
not only improve, but stone in the bladder actually dissolve.
However, scientists have been unable to explain why a cat gets the
disorder in the first place. Two cats in the same household have the same
activities, eat the same food, and have the same levels of stress. Why
does one develop feline urological syndrome while the other does not?
Delmar F. Finco, DVM, PhD, of the University of Georgia, working
under a grant from Morris Animal Foundation, is testing several theories.
The Foundation,a non=profit organitzation, funds studies of the diseases
of dogs, cats, horses, and zoo animlas through grants to veterinary colleges.
Dr. Finco is feeding cats on a restricted basis offering foos for
one hour daily, to see if the composition of the urine in these animals
differd from that of cats allowed to nibble at will.
Studies have shown that cats develop alkaline urine durint the
digestive process after eating. Cats allowed to nibble throughout the day
therefore have a highly alkaline urine much of the time. Dr. Finco believes
that this raised alkalinity, at the same time that the urine is filled with
minerals from the food being digested, may lead to a "crystal shower" or
a formation of crystals in the urine which may induce feline urological
syndrome.
Urine, he explained, is a super-saturated solution, filled with
minerals. Canges in the urine can produce crystallization, either
spontaneously from an increase in the number of minerlas dissolved in the
urine, or from changes in the composition of the urine itself. These crystals
can block the cat's urinary tract, producing irritation, discomfort, and
if the blockage is not detected in time, death.
Mineral content in the urine can be influenced by the cat's diet,
the effiency of the cat's digestive system, the way the animal's kidneys
function, and urine volume.
During the study, Dr. Finco will measure frequency of urination,
urine pH, mineral concentration volume, and check for crystal formation.
If feeding patterns prove to make significant changes in any of these factors,
it will give scientists and cat owners another clue to the causes of feline
urological syndrome. In addition, if risk factors can be identified, owners
could be provided with guidlines to help manage their cats' care program
more efficiently.
Reproduce without permission from November, 1984 edition of
Cats Magazine
tlh
|
| The following is a (long) excerpt from an article called
"Special Foods for Special Cats". This article appeared in the Feb 1986
issue of Cat Fancy and is reproduced without permission.
Food and FUS
Feline Urological Syndrome (FUS) is a term used to cover a range
of urinary tract problems that manifest themselves through the cat's straining
in the litter box, frequent but small-volume urination, bloody urine and
blockage of the urinary tract. The irritation of the urinary tract, or
blockage when it occurs, is caused by mineral crystals that bond together
and form bladder stones. FUS accounts for at least 10% of all cats admitted
to hospitals. It is equally likely to occur in both males and females,
but males are more apt to suffer blockage because of their small urethras,
and only males die of the disease.
Preventing FUS has eclipsed most other concerns on the development
of special diets for cats. While only 1 percent of pet cats ever contract
FUS, its victims nonetheless number 100,000 per year, and once a cat owner
has dealt with the disease, he or she is always concerned about preventing
it.
Why mineral crystals form is not fully understood, but there is
much speculation. In an article, "Common Questions About the Nutrition
of Dogs and Cats," Dr. David Kronfeld hints at apossible cause: "When we
feed cereals instead of flesh to dogs and cats, they develop a multitude
of complaints, most of which have been overcome by research. A few remain
such as urinary crystals and stones in cats and bloat in dogs." The NRC
[National Research Council], however, conducted a study that concluded:
"when properly processed and supplemented, both plant and animal products
are suitable for dogs and cats." Realistically, cats are going to get plants
products in their diets. Even feral cats consume a fair amount of vegatable
matter since they classically eat the entrails of their prey first, so perhaps
the key words are "properly processed and supplemented."
Current thinking among many FUS experts is that limited magnesium,
coupled with a low urine pH, creates a poor environment and lack of mineral
supply for formation of urinary tract crystals. A cat food can show a
relatively low ash content and still be high in magnesium, so conscientious
manufacturers have started putting magnesium content on their labels.
In an article, "Economics and rationale of dietary management of
feline urologic syndrome," by Lon D. Lewis, DVM, PhD, and Mark L. Morris,
Jr., DVM, PhD, a seven-day study on 12 cats and many kinds of cat foods
was discussed. They said, "Recurrance of FUS can be prevented in 85 to
100 percent of all cases by maintaining the cat on a diet of not more than
20 milligrams of magnesium per 100 killocalories, and that maintains a urine
pH of less than 6.4."
Which foods included in the test met the criteria? Of the canned
foods, Prescription Diet Feline s/d, Prescription Diet Feline c/d, Science
Diet Feline Maintainence, five 9-Lives flavors(Country Chicken 'n' Gravy,
Choice Cuts and Cheese, Tuna & Chicken, Savory Stew, and Beef & Egg), Friskies
Buffet Beef & Liver and Fancy Feast Beef & Liver. Among the dry foods tested,
Prescription Diet Feline c/d and Science Diet Feline Maintainence ahd the
lowest concentration of magnesium. For the consumer, the number to llok
for on a label is a magnesium content of 0.1 percent or less. [Prescription
diet * is also known as Hill's *]
To put the issue in perspective, keep in mind that since only 1
percent of the cat population ever develops FUS, 99 percent will probably
live long and healthy lives on foods that have contain higher levels of
magnesium. Most veterinarians recommend low-magnesium diets only for cats
that have already shown signs of developing FUS.
Since the discovery that struvite crystals are less likely to form
in acid urine, one of the treatments for FUS victims has been to add urinary
acidifiers to the cat's diet. These acidifiers usually ammonium chloride
or methionine, can be effective if used regularly and under veternary
supvervision, but they can also cause excessive loss of bone minerals and
potassium and can lower the blood pH to a level so dangerous that kittens
can die from eating too much of the treated food.
This is just one of the findings from a study conducted by Dr. Tony
Buffington, Quentin Rogers, and Jim Morris at U.C. Davis Veterinary Medical
Teaching Hospital. The complete report of this study was recently published
in Feline Practice, and a summary of the findings was presented at a meeting
hosted by Carnation.
Dr. Buffington and his colleagues used three groups of 10 cats each.
Group 1 received foods high in magnesium oxide, group 2's food was high
in magnesium chloride, and group 3 was fed a low-magnesium diet. By the
end of the study, all of the cats in group 1 showed signs of FUS, and one
cat died. In group 3, one cat blocked, but in group 2 -- the group with
the high magnesium chloride -- none of the cats showed signs of FUS. The
researchers concluded that the key to preventing or comtrolling FUS is
controlling the pH level of the diet rather than the amount of magnesium.
Magnesium oxide produces an alkaline urine, while magnesium chloride produces
an acid urine. Acidity interferes with the formation of struvite crystals;
alkalinity contributes to their formation.
According to the U.C. DAvis study, safe pH levels are between 5.9
and 6.4. There is a gray area between 6.4 and 7.1 that may be tolerated
by the body chemistries of certain cats, but anything above 7.1 is considered
to be very dangerous for any cat. At the other end of the spectrum, anything
below 5.9 is also dangerous because it lowers the pH level of the blood.
In this study, cat foods that ranked best in producing lower pH
levels for more acidic urine were Science Diet and Tamiami. Soft moist
diets also proved beneficial because phosphoric acid is used as preservative
in these foods and that single ingredient helps acidify the urine.
The U.C. Davis team also found that how cats are fed is important
in controlling the pH level. The worst schedule is to fedd your cat three
times a day -- that keeps the pH level high all day long. They say it is
better to free-feed, allowing the cat to nibble and drink at will, or to
feed one meal a day, which most cats would not like but in theory would
allow the pH level to drop during a substantial portion of the 24-hour peroid.
Each cat is like a unique chemistry set. If you are concerned about
whether or not your cat's favorite food is predisposing it to FUS, go to
the pharmacy and purchase a roll of litmus paper and monitor the pH of your
cat's urine. Be sure to get a color guide that will help you interpret
the pH level. Dr. Margaret Reister, CAT FANCY's "Ask the Vet" columnist,
reccomends checking the urineearly in the morning, when the urine is
concentrated. Dragging the litmus paper through the litter will not affect
the accuracy of the reading, and it will let you know if you ought to change
foods and whether a a new food is producing the desired result.
Prescription Foods
Hill's makes three foods that fall under the FUS heading. Your
veterinarian will prescribe the sppropriate one depending on the specific
nature of your cat's problem.
Feline c/d is reccomended for urinary stoppages. In other words,
it is for the plugged cat, the cat with crystals or stones in the bladder
or urethra. Feline c/d contains limited minerals, enough for good nutrition,
but not enough to leave much left over for stone formation.
Feline s/d (stone diet) is the latest in Hill's line of Prescription
Diets. It is formulated to dissolve bladder stones and acidify urine,
therefore allowing little opportunity for struvites formation. Often s/d
is prescribed as the sole food for three months. If the cat shows significant
improvement, it can then be switched to another low_ash, low_magnesiu, diet
such as Feline c/d or one of the specialty foods reccomended for FUS cats.
(The article goes on to discuss Feline k/d which is recommended for
cats with compromised kidney function, but my fingers are wearing out, so
unless someone requests this info, I'll stop here.
|
| FUS
I had a male neutered cat, that had a serious problem with FUS.
After having to take him back for the 3rd time in 3 weeks to be
catherized, the doctor had advised me that I should either have
him put to sleep or to consider an operation in which they would
insert a plastic tube into the urethra. This was back in 1976 and
and the operation at that time would cost over $300. Now the cost
of the operation wasn't what bothered me, the odds were. I was
told that this operation was less that 25% successful, and also
that it was a painful operation. I decided that at the time the
best thing that I could do for Smokey was to have him put to sleep.
If the odds had been better, then I would have paid the price im-
mediately, but Smokey was in so much pain at the time, I could not
bear to see him in pain any longer. He would scream, if you even
picked hime up. Now, one thing that I thought was really strange
was the fact that the doctor said that neutered male cats were most
likely to have this problem. Is this true for you, or was your
cat a female? Ever since that time I have been real scared of having
my male cats neutered, so I always stuck with female cats. I know
that it is best to have males neutered, but I can not see the since
in doing so if in the end there will be pain for the cat. Anyone
out there that has had this problem, could you please tell whether
your cat is male or female. I am just curious to know whether or
not this problem if found mainly in males. Thanks Sarah
|