Calcium Oxalate - what do you know?
2 posters
Page 1 of 1
Calcium Oxalate - what do you know?
Renee 3/30/2012, 1:02 pm
I went back and read the thread that Lex wrote about these type of stones, but I was hoping we could open up a bigger discussion on them, especially those in rescue that may have dealt with them.
My foster pug Kobe (he's probably a hospice, but who knows) had stones removed 2 weeks ago. There were about 8-9 stones removed, all relatively small in size individually, smooth and round, but bronze colored.
Anyway, the analysis came back 100% calcium oxalate.
Of course, the first thing the vet suggested was to put him on Hill's u/d - for life.
I will put him on it, if need be, but I am not ready to just "give in", and go with it as the first choice. Yes, I do believe some prescription diets have their place, and for many people they are lifesavers... but, I am more than willing to put the time, effort, money, and learning in order to help him in a more natural & healthy way.
So, what do you all have for me?
My foster pug Kobe (he's probably a hospice, but who knows) had stones removed 2 weeks ago. There were about 8-9 stones removed, all relatively small in size individually, smooth and round, but bronze colored.
Anyway, the analysis came back 100% calcium oxalate.
Of course, the first thing the vet suggested was to put him on Hill's u/d - for life.
I will put him on it, if need be, but I am not ready to just "give in", and go with it as the first choice. Yes, I do believe some prescription diets have their place, and for many people they are lifesavers... but, I am more than willing to put the time, effort, money, and learning in order to help him in a more natural & healthy way.
So, what do you all have for me?
Renee-
- Number of posts : 5694
Location : Anchorage Alaska -
Whole Dog Journal on Oxalate
northernwitch 3/30/2012, 1:12 pm
Preventing Bladder and
Kidney Stones in Dogs
Diagnosing, treating, and preventing calcium
oxalate stones in dogs.
Bladder
and kidney stones are serious problems in dogs as well as people. These
conditions – which are also known as uroliths or urinary calculi – can be
excruciatingly painful as well as potentially fatal. Fortunately, informed
caregivers can do much to prevent the formation of stones and in some cases
actually help treat stones that develop.
Last
month, we described struvite stones (see “Is Your Dog Stoned?” WDJ April 2010).
Struvites contain magnesium, ammonium, and phosphate. They almost always occur
in the bladder in combination with a bacterial infection and are most
frequently found in small-breed females.
This
month, we examine calcium oxalate or “CaOx” stones.
Calcium
oxalate stones
CaOx stones occur in both the bladder (lower urinary tract) and kidneys (upper
urinary tract) of male and female dogs. Most calcium oxalate uroliths are
nephroliths (found in the kidney), and most of the affected patients are
small-breed males. CaOx uroliths are radiopaque and most are easily seen on
radiographs (X-rays).
In
addition to breed and sex, risk factors for CaOx stones include being
overweight, under-exercised, neutered, and eating a dry food diet, which
contributes to more concentrated urine. Small dogs are thought to be more
susceptible because they drink less water relative to their size than large
dogs do.
One risk
factor is insufficient or abnormal nephrocalcin, a strongly acidic glycoprotein
present in normal urine that inhibits calcium oxalate crystal growth. Dogs who
produce normal and sufficient nephrocalcin have a reduced risk of developing
calcium oxalate stones.
Certain
prescription drugs contribute to the formation of CaOx uroliths. Prednisone and
other cortisone-type medications prescribed for inflammatory illnesses such as
arthritis, itchy skin, or inflammatory bowel disease, can contribute to the
formation of CaOx stones. So can the diuretic drug furosemide (brand names Lasix
or Salix), which is given to dogs with congestive heart failure. Thiazide-class
diuretics are recommended in place of furosemide for dogs who are prone to
forming CaOx stones. Some nutritional supplements, such as vitamins C and D,
are believed to contribute to oxalate stone formation.
Uroliths
can develop in any breed, but the greatest number of calcium oxalate stones
presented for analysis have come from Miniature Schnauzers, Bichon Frises,
Standard Schnauzers, Lhasa Apsos, Shih Tzus, Yorkshire Terriers, Miniature
Poodles, Pomeranians, Parson Russell Terriers, Papillons, Keeshonds, Samoyeds,
Chihuahuas, Cairn Terriers, Maltese, Toy Poodles, West Highland White Terriers,
Dachshunds, and mixed breeds.
Cocker
Spaniels, German Shepherds, Golden Retrievers, and Labrador Retrievers are
believed to be at decreased risk of CaOx stones.
Conventional
veterinary practitioners tend to consider calcium oxalate stones irreversible,
unaffected by diet or medical therapy, and untreatable except by surgery. They
may attempt to remove small bladder stones by flushing the bladder with sterile
saline, or perform shock wave or laser lithotripsy (processes that break stones
into small pieces that can be flushed out or excreted in the dog’s urine).
Uroliths
pose a more serious problem for male dogs than females, because their urine
travels through a hollow bone (os penis) that surrounds the urethra within the
penis. The bone cannot stretch or expand to accommodate a stone traveling
through it, and obstructions readily result.
For males
with recurring stones, a surgical procedure called urethrostomy sends urine on
a new path, avoiding the os penis. The urethrostomy creates a new urinary
opening in the scrotum area. This type of surgery cannot be performed unless
the dog is neutered; if he is intact, he can be neutered at the time of the
urethrostomy.
In up to
60 percent of conventionally treated patients, calcium oxalate stones recur
within three years. In dogs with Cushing’s Disease (hyperadrenocorticism) or
excessive calcium in the blood (hypercalcemia), both of which predispose dogs
to CaOx stones, the recurrence rate is faster. It’s important to treat these
underlying causes, if found, to help prevent recurrence. The recurrence rate
among Bichons is higher than for any other breed.
Calcium
oxalate crystals are of concern, but their presence doesn’t necessarily mean
your dog is at risk of forming stones. Crystals are significant only if found
in fresh urine. Crystals that form when urine is refrigerated or analyzed more
than 30 minutes after collection may be incidental and not indicative of a
problem. Dogs with calcium oxalate crystals in fresh urine should be monitored,
and if the finding continues, steps should be taken to reduce the risk of stone
formation, particularly in breeds most commonly affected.
Death
sentence to discovery
In 1997, Molly McMouse, a 14-year-old Lhasa Apso belonging to Leslie Bean of
Houston, Texas, was diagnosed with very dense, inoperable calcium oxalate
stones affecting both kidneys. Bean owned three more Lhasas – 15-year-old
FuzzerBear, 13-year-old Peepers, and 11-year-old CB Wigglesworth – who were closely
related to Molly. Fearful that her other dogs could be afflicted by the same
condition, Bean had them tested, and was shattered when each received the same
diagnosis.
“My
husband and I were told that oxalates only proliferate in size and number,” she
recalls, “and that as the calcification of their kidneys increased, all four of
our dogs would die, probably within six to nine months.”
At the
time, Bean was founding director of patient advocacy at the University of Texas
MD Anderson Cancer Center, a position that helped her contact medical experts
of every description. She checked with veterinarians, veterinary researchers,
and directors of veterinary schools and laboratories around the country, only
to receive the same sad news from all.
“Every
one of them said these stones cannot be dissolved,” she says. “They all felt
bad about it, but they agreed that the prognosis for my dogs was hopeless.”
Bean’s
Lhasas had been on a premium, holistic food, but after their diagnoses, at the
recommendation of their veterinarians, Bean put them on a low-protein,
low-phosphorus, low-sodium prescription diet. The dogs disliked the new food
and their to-the-floor show coats rapidly dulled.
At that
point, Bean says, “I accepted the fact that my dogs were going to die but I
wanted to make their final months as terrific as possible.” Tossing the
prescription food, she began feeding fresh foods such as lamb and peas, chicken
and rice, and beef and broccoli. “I figured if they had so little time, they
were damned well going to enjoy what they ate,” she says, “and they loved it. I
can still see them dancing with joy when I carried their bowls to their places.
Literally within two weeks they began acting more energetic, looked younger,
had a spring in their step, and their eyes were clearer. Their coats looked
better, too, and we soon had to cut almost an inch in length from each dog
every month. Although that is common in young Lhasas in show coat, the rate of
growth slows with age, so this was a really noticeable difference.” Because
oxalic acid forms strong mineral bonds that can become calcium oxalate crystals
and eventually CaOx stones, Bean speculated that low-oxalate foods might help
prevent the stones’ formation (see “Oxalates in food,” page 9), and she made
those ingredients the foundation of her dogs’ menus.
Protein
In the past, diets restricted in both protein and phosphorus were thought to
reduce the risk of calcium oxalate formation. Studies found, however, that
dietary phosphorus restriction increased calcium absorption and the risk of
calcium oxalate formation, while higher levels of dietary protein reduced the
risk of uroliths. Current recommendations for dogs prone to forming CaOx
stones say that diets should not be restricted in protein, calcium, or
phosphorus.
In
February 2002, The American Journal of Veterinary Research published a study
conducted at the University of Minnesota College of Veterinary Medicine’s
Minnesota Urolith Center that compared dietary factors in canned food with the
formation of calcium oxalate uroliths in dogs, with surprising results. Canned
diets with the highest amount of carbohydrate were associated with an increased
risk of CaOx urolith formation. Contrary to commonly accepted beliefs, the
study concluded that “canned diets formulated to contain high amounts of
protein, fat, calcium, phosphorus, magnesium, sodium, potassium, chloride, and
moisture and a low amount of carbohydrate may minimize the risk of CaOx urolith
formation in dogs.”
In
contrast, Hill’s Canine u/d, often prescribed for dogs prone to forming CaOx
stones, is low in protein, calcium, phosphorus, magnesium, and potassium.
At the
beginning of her nutritional experiment, Bean reduced her dogs’ protein levels
so much that they began to lose muscle mass. “After much research, analysis,
and discussion with my veterinarians,” she says, “I increased their protein
levels to 33-40 percent of the total volume of food. They quickly regained
their lost weight and muscle, and there were no further problems with muscle
loss.”
As Bean
discovered, it’s very important not to reduce protein too much. Even the most
severely phosphorus-restricted diets for renal failure recommend feeding a
minimum of 1 gram of protein per pound of body weight daily.
Recheck
As the Lhasas continued to thrive, their primary veterinarian, Jane Milan,
encouraged Bean to return them for another ultrasound test to the veterinarian,
a specialist in internal medicine, who had first diagnosed them. “I just didn’t
want to hear bad news,” says Bean, “so I kept putting it off.”
Eight
months after their diet change and past or near their predicted death dates,
she made the appointment. “I was really nervous,” she says. “They looked
terrific, but I had no way of knowing what was going on inside them. And the
vet was with them for an unusually long time, which made me even more anxious.”
Finally the somber-looking veterinarian returned to the waiting room carrying
two of the dogs and said, “I don’t know how to tell you this.”
Bean
assumed that her other two dogs had died during their ultrasound tests and she
nearly fainted, but the vet’s good news revived her. The calcium oxalate stones
that had been ticking time bombs were nowhere to be found. That’s what caused
the long delay – he could not at first believe his test results. “The two older
dogs still had five tiny stones,” she says, “but they had shrunk to the size of
pin-dots, and they soon disappeared.”
Despite
the kidney damage already caused by their calcium oxalates, each of the already
senior Lhasas lived several more years. FuzzerBear died at age 19, the other
three lived to be 18, and frequent check-ups showed all four to be completely
free from calcium oxalate stones for the rest of their lives.
At the
suggestion of their veterinarians, Bean continued to study canine nutrition and
assembled a set of guidelines that described her dogs’ regimen.
“I am not
a veterinarian licensed to practice veterinary medicine in any state and make
no claims or representations as such,” Bean reminds everyone. “I am simply a
pet owner whose dogs suffered from intractable problems. I developed
FuzzerFood, named for Fuzzerbear, based upon the independent research I
conducted to help my own dogs. My discoveries are not intended to be veterinary
advice, nor are they a drug, biologic, or other therapeutic or diagnostic
substance or technique designed to replace a consultation with a qualified
veterinarian.”
She
recommends that owners of dogs with calcium oxalate stones work closely with
their veterinarians, beginning with a baseline ultrasound, complete blood
panel, and urinalysis. “Start now if you have not already,” she suggests, “to
maintain records of blood work and urinalysis reports as well as your own notes
as you go.”
Water,
the key ingredient
The most important thing you can do for a stone-prone dog is increase fluid
consumption and opportunities to urinate. Urine becomes concentrated when
insufficient fluids are consumed or when dogs are not able to relieve
themselves and have to hold their urine for long periods. And concentrated
urine contributes to supersaturation with minerals that can precipitate into
crystals and lead to stones.
One way
to encourage dogs to increase their water consumption is to add salt to their
food, but salt is controversial when it comes to calcium oxalate uroliths.
Increasing dietary salt encourages the kidneys to excrete more calcium, raising
urinary calcium levels.
One might
predict that increased sodium would therefore lead to increased calcium oxalate
formation, but that isn’t necessarily true. In a 2003 study, dogs were fed dry
diets containing varying amounts of sodium. The diets that contained 300 mg
sodium (about ⅛ teaspoon of salt) per 100 calories significantly reduced
urinary calcium oxalate supersaturation over diets containing 60 mg or even 200
mg sodium per 100 calories. Increased fluid consumption resulting from the
thirst generated by additional salt probably offset the increase in calcium
excretion. A human retrospective study published in 2009 concluded, “Increasing
urine sodium does not appear to increase the risk of calcium oxalate
nephrolithiasis (kidney stones).”
Bean,
however, does not add salt to food. The majority of human studies indicate that
adding salt is inadvisable, and many who elected to apply the FuzzerFood
regimen for their own dogs were unsuccessful in attempts to dissolve or prevent
recurrence of calcium oxalate stones when they departed from the guidelines
Bean developed for her own dogs.
You can
help your dog drink more by providing fresh water in clean dishes in several
locations; changing the water frequently; adding small amounts of tuna water,
salt-free or low-sodium broth, a favorite juice, or other flavoring agent to
drinking water in addition to offering plain water; adding water to food;
offering ice cubes as treats; using a pet water fountain to provide
continuously filtered fresh running water; offering water at every opportunity;
and carrying water and a portable bowl while hiking or traveling.
What type
of water should you use? Bean prefers steam-distilled water because it contains
no minerals that might combine with excess oxalic acid. Physicians she
consulted with told her that both hard and soft water may increase the risk of
calcium oxalate formation. Reverse-osmosis water filters remove 95 percent of
minerals, making RO-filtered water nutritionally similar to distilled water.
Not all
minerals in water contribute to kidney or bladder stones. In several studies
conducted in the 1990s, human patients who formed calcium oxalate nephroliths
drank a French mineral water containing high levels of calcium (202 parts per
million) and magnesium (36 ppm). Nearly every risk factor for calcium oxalate
nephroliths improved significantly. The same patients also drank local tap
water and mineral water with low calcium/magnesium concentrations, neither of
which improved the measured risk factors. The researchers concluded, “The risk
of calcium oxalate stone formation can be significantly reduced by consumption
of mineral water which is rich in calcium and magnesium.”
Other
research on the effects of hard and soft water on urolith formation has shown
mixed results regarding risk, possibly due to variations in mineral content and
ratios, along with factors such as whether the water was given with or between
meals. For this reason, distilled water may be safest, particularly for dogs
with kidney stones or recurrent bladder stones.
Getting
extra water into your dog is only part of the urolith-prevention strategy. Just
as important is the frequent release of urine. Give your dog many opportunities
to go outside during the day. If your dog is indoors alone or crated for hours
each day, find a way to create a convenient elimination area using plastic,
newspapers, towels, a patch of sod, or whatever you can devise to keep your dog
from having to hold her urine for long periods.
Urinary
pH
Calcium oxalate stones form in urine that is acidic, typically measuring
between 5.0 and 6.5 on the pH scale. Calcium oxalate crystals are generally not
sensitive to urinary pH, but marked acidification that induces metabolic
acidosis can promote calcium oxalate stone formation due to increased urinary
calcium concentration.
A common
recommendation for dogs prone to forming calcium oxalate stones is to alkalize
the body with foods or medications to bring the urinary pH closer to 7, which
is neutral. Alkalizing the urine will not cause existing stones to dissolve but
may help prevent new stones from forming. It’s important not to try to alkalize
the urine too much, as this can lead to the formation of calcium phosphate
stones.
You can
monitor your dog’s urine by holding a pH test strip in the stream or by
collecting urine in a paper cup or clean dish for testing.
But don’t
be surprised if your dog’s urinary pH stays where it is. Leslie Bean describes
her careful monitoring of her dogs’ urinary pH as a source of discouragement.
“I thought that unless I could bring their pH higher, their stones would
increase,” she says. “To the contrary, not only did they not increase, the
stones dissolved. I learned that the key is to monitor the pH and know where
you are, but not to panic if the urine stubbornly remains more acidic than you
would like.”
Oxalates
in food
Oxalic acid is found in both plants and animals, with plants containing higher
levels. It forms strong bonds with sodium, potassium, magnesium, and calcium,
creating oxalate salts. The term “oxalate” usually refers to a salt of oxalic
acid, one of which is calcium oxalate. Sodium and potassium oxalate salts are
water-soluble, but calcium oxalate is not, and it is what forms CaOx uroliths.
Interest
in low-oxalate diets has increased recently because of possible links between
oxalates and human kidney stones, arthritis, fibromyalgia, female vulvar pain,
autism and other pervasive developmental disorders, and chronic inflammation.
As a result, there is growing demand for accurate data on the oxalate content
of foods. When Bean began her research 13 years ago, much of the information
published about this subject was quite old. Eventually she found a small
booklet published by the University of California at San Diego, “Oxalate
Content of Select Foods,” which featured more current data and gave her a list
of foods to include and avoid.
Today,
the Oxalosis and Hyperoxaluria Foundation publishes an up-to-date list of foods
and their oxalate content. Based on research from 2008 and revised as new
figures become available, this report divides foods into very high, high,
medium, and low levels of oxalates according to serving size (see “Oxalate
Content of Various Foods,” next page). The foods in Group 1 (very high-oxalate
foods) are best avoided by dogs prone to calcium oxalate stones. Group 2
(high-oxalate) foods should also be avoided.
Group 3
foods have moderate oxalate levels. They can be fed in moderate amounts as long
as calcium is also given with the meal. Group 4 (low-oxalate foods) are “green
light” ingredients, and can be fed in any quantity, though they should still be
combined with calcium. See the complete list, available through the Oxalosis
and Hyperoxaluria Foundation, for information about additional foods, including
herbs, spices, combination foods, and beverages.
Some
websites and publications incorrectly list meat, liver, other organ meats,
shellfish, cheese, yogurt, broccoli, sardines, cherries, brussels sprouts,
olives, and strawberries as dangerous for CaOx-sensitive dogs, based on
outdated information. All of those foods are actually low in oxalates.
Designing
the menu
Because it’s difficult to find commercial foods made without ingredients that
are problematic for dogs prone to CaOx stones, home-prepared diets may produce
the best results. For those who already feed a home-prepared diet to their
dogs, the adjustments are simple. For those who are new to dog food
preparation, designing an effective menu need not be complicated. Your dog’s
food can be prepared along with your own meals or made in advance and
refrigerated or frozen in single portions for later use.
Start by
feeding different types of meat, poultry, eggs, fish, and dairy in order to
provide a variety of flavors and nutrients. The food Bean feeds her dogs is
about 40 percent protein by volume, but higher protein levels work well for
many dogs. The rest of the diet should be low-oxalate grains and/or vegetables.
While
Bean doesn’t include organ meats in her FuzzerFood guidelines, adding ½ ounce
(about 1 tablespoon) of liver per pound of other foods will add valuable
nutrients to a home-prepared diet.
Meat can
be ground, cut into cubes, or served in a single piece, assuming your dog
doesn’t have problems chewing. It can be fed raw or cooked. Because CaOx dogs
on raw bone-based diets have continued to form stones, the FuzzerFood regimen
does not include bones. Freeze-dried liver and similar dog treats are
appropriate for training and special occasions. Avoid treats that contain
high-oxalate ingredients, and factor treats into the daily food allotment of
overweight dogs.
Boiling
vegetables in water greatly reduces their oxalate content, while steaming
reduces levels slightly. Of course, boiling reduces nutritional content, so
it’s a trade-off. When you feed Group 3 (moderate-oxalate) vegetables, consider
giving smaller amounts raw and larger amounts cooked. Adding digestive enzymes
to food at serving time helps replace enzymes destroyed by heat.
Most
10-pound dogs need less than 1 cup of food by volume, while dogs weighing 50
pounds may need closer to 3 cups per day. Bean’s Lhasas maintain their 12- to
14-pound body weight on slightly more than 1 cup per day. The amount to feed
will vary according to your dog’s activity level and the amount of low-calorie
vegetables in the diet. Because key supplements should be given twice a day
with food, consider feeding breakfast and dinner rather than one meal per day.
Calcium
In the past, calcium was thought to be a risk factor for the formation of
calcium oxalate stones. Later studies found, however, that calcium binds
oxalate and thus actually reduces the risk of calcium oxalate stones when given
with meals.
When she
spoke with urologists who deal with human kidney stones, Bean learned that
supplementing homemade food with calcium citrate neutralizes oxalates in urine,
so she began giving it to her dogs with meals while avoiding all other mineral
supplements. “Citrate is an important natural inhibitor of calcium oxalate
stones,” she says. “When calcium citrate is combined with food at mealtime, it
helps absorb and bind excess oxalic acid in the gut. This bound oxalate cannot
be absorbed and is excreted through the feces. This means that it does not get
into the bloodstream or kidneys to cause stones.”
Pure
calcium citrate powder is inexpensive and easy to use. Bean adds 300 to 350 mg
of NOW brand Vegetarian Powdered Calcium Citrate to each 8 ounces (½ pound) of
fresh food to balance the diet’s calcium:phosphorus ratio. Calcium citrate
should only be added to homemade diets, or to the fresh portion of a combined diet,
as commercial diets should already contain the right amount of calcium (though,
unfortunately, they rarely use calcium citrate).
Supplements
For more than 40 years, the medical literature has reported on the success of a
simple nutritional therapy for the prevention of calcium oxalate stones in
humans using magnesium and vitamin B6. In studies published in The American
Journal of Clinical Nutrition, The Journal of the American College of
Nutrition, and other medical journals since 1967, patients with longstanding,
recurrent calcium oxalate kidney stones received 200, 300, or 500 mg magnesium
oxide with or without 10 mg pyridoxine (vitamin B6) daily for five years or
more, during which their stone formation fell by more than 90 percent. When
measured, their urine increased its ability to keep calcium oxalate in
solution.
Because
vitamin B6 deficiencies can contribute to an increase in oxalate production,
many veterinarians prescribe this vitamin for dogs prone to CaOx stones. Severe
vitamin B6 deficiencies may result from genetic disorders. Vitamin B6 is
available as an oral supplement or by injection. Follow label directions or, if
using a human product, give ¼ of the total dose for each 25 pounds of body
weight.
A
B-complex supplement provides all of the needed B-family vitamins. Give 50 mg
twice per day to dogs weighing 50 pounds or more, and one-fourth or half that
amount to smaller dogs. The FuzzerFood regimen includes Omega-3 fish or salmon
oil, a B-complex vitamin, and vitamin E, with optional CoQ10, magnesium,
glucosamine, digestive enzymes, and probiotics.
Magnesium
can have a laxative effect, so begin at the low end of the range, which is 3 to
5 mg per pound of body weight per day, divided into morning and evening doses
and given with meals. Magnesium supplementation is contraindicated for dogs in
renal failure, so if that is your dog’s condition, use this under your
veterinarian’s supervision only as long as there are stones, then discontinue.
Bean does
not use either vitamin C or vitamin D (including cod liver oil, which contains
vitamin D) because vitamin C is reported to convert to oxalate, thus possibly
increasing the risk of stone formation, and vitamin D promotes calcium
absorption, which leads to increased urinary calcium.Most multi-vitamins
contain vitamins C and D, so it’s important to read labels.
Supplements
manufactured for human consumption come in a wider variety than do veterinary
supplements, making it easier to find human products that avoid these
ingredients. Adjust the recommended human dose for your dog by weight.
Some
researchers have found that glucosamine supplements, which are commonly used
for arthritis, may help prevent calcium oxalate crystals from adhering to the
bladder wall. While this treatment is still speculative, glucosamine is safe to
give and may be helpful in preventing CaOx bladder stone formation.
When Bean
asked Traditional Chinese Medicine veterinarian Cory Stiles, DVM, for advice
from that perspective, Dr. Stiles recommended Lysimachia-3, a traditional
Chinese blend of three herbs, Jin Qian Cao or Desmodium, Hai Jin Sha or
Lygodium Spores, and Ji Nei Jin or Gallus, which is designed to treat human
digestive disorders, gall stones, and kidney stones.
“Lysimachia-3
comes in tablets,” says Bean, “which we crushed and mixed with food, or the
tablet can be placed in a small amount of low-fat cream cheese, or the dog can
simply be ‘pilled’ by putting it down the throat. My dogs had no objection to
having these tablets crushed and mixed with their food, and Lhasas are notoriously
picky.” Dr. Stiles’ recommended dose is 1 tablet per 25 pounds body weight
given twice daily until stones are dissolved. Then give Lysimachia-3 daily for
another month, then start using it every other day, then every three days, and
if all looks good, dose it three times per week every other week, and finally,
daily for one week out of every four to six weeks.
Preventive
medical treatment
Potassium citrate is a nutritional supplement that increases citrate levels in
the urine, attracting calcium away from oxalates. When calcium binds to
citrate, the resulting calcium citrate tends to remain dissolved instead of
precipitating out as a mineral deposit. Potassium citrate also has an
alkalizing effect on the urine, which can help to prevent the formation of
calcium oxalate stones, though it won’t dissolve existing stones. High blood
potassium levels are dangerous, so a veterinarian’s supervision and follow-up
blood tests are recommended when using potassium citrate. This supplement
should usually not be given when dietary changes alone maintain the urine’s pH
at 6.5 or above.
Calcium
citrate achieves the same goals of alkalizing urine and binding oxalates
without the risk of elevated potassium that can be posed by potassium citrate.
That’s why Bean considers calcium citrate a better option for her dogs’
homemade diets.
Dogs who
continue to form stones despite other steps to minimize risk may be prescribed
hydrochlorothiazide, a thiazide diuretic, to increase the amount of urine
produced while reducing urinary calcium oxalate saturation.
The
stress connection
In addition to good food and ample water, dogs need a stable home life, active
exercise, and interesting activities. Some researchers speculate that stress
plays a role in the development of kidney and bladder stones. When changing
your dog’s diet, do what you can to keep the introduction of new foods fun and
stress-free. Fortunately, most dogs love fresh food. Just as importantly, do
what you can to relax and let go of the stress that concern about your dog’s
health brings to your own life. The more you and your best friend enjoy each
other’s company with play, exercise, and shared quiet moments, the better
you’ll both feel.
Next
month: The final installment of our bladder/kidney stone series examines
cystine, calcium phosphate, silica, and ammonium urate or uric acid uroliths.
CJ
Puotinen is the
author of The Encyclopedia of Natural Pet Care and other holistic health books.
She lives in Montana, and is a frequent contributor to WDJ.
San
Francisco Bay Area resident Mary Straus has spent more than a decade
investigating and writing about canine health and nutrition topics for her
website, DogAware.com.
Read More on These Topics
Comments (0)
Be the
first to comment on this post using the section below.
Add your comments ...
Kidney Stones in Dogs
Diagnosing, treating, and preventing calcium
oxalate stones in dogs.
Bladder
and kidney stones are serious problems in dogs as well as people. These
conditions – which are also known as uroliths or urinary calculi – can be
excruciatingly painful as well as potentially fatal. Fortunately, informed
caregivers can do much to prevent the formation of stones and in some cases
actually help treat stones that develop.
Last
month, we described struvite stones (see “Is Your Dog Stoned?” WDJ April 2010).
Struvites contain magnesium, ammonium, and phosphate. They almost always occur
in the bladder in combination with a bacterial infection and are most
frequently found in small-breed females.
This
month, we examine calcium oxalate or “CaOx” stones.
Calcium
oxalate stones
CaOx stones occur in both the bladder (lower urinary tract) and kidneys (upper
urinary tract) of male and female dogs. Most calcium oxalate uroliths are
nephroliths (found in the kidney), and most of the affected patients are
small-breed males. CaOx uroliths are radiopaque and most are easily seen on
radiographs (X-rays).
In
addition to breed and sex, risk factors for CaOx stones include being
overweight, under-exercised, neutered, and eating a dry food diet, which
contributes to more concentrated urine. Small dogs are thought to be more
susceptible because they drink less water relative to their size than large
dogs do.
One risk
factor is insufficient or abnormal nephrocalcin, a strongly acidic glycoprotein
present in normal urine that inhibits calcium oxalate crystal growth. Dogs who
produce normal and sufficient nephrocalcin have a reduced risk of developing
calcium oxalate stones.
Certain
prescription drugs contribute to the formation of CaOx uroliths. Prednisone and
other cortisone-type medications prescribed for inflammatory illnesses such as
arthritis, itchy skin, or inflammatory bowel disease, can contribute to the
formation of CaOx stones. So can the diuretic drug furosemide (brand names Lasix
or Salix), which is given to dogs with congestive heart failure. Thiazide-class
diuretics are recommended in place of furosemide for dogs who are prone to
forming CaOx stones. Some nutritional supplements, such as vitamins C and D,
are believed to contribute to oxalate stone formation.
Uroliths
can develop in any breed, but the greatest number of calcium oxalate stones
presented for analysis have come from Miniature Schnauzers, Bichon Frises,
Standard Schnauzers, Lhasa Apsos, Shih Tzus, Yorkshire Terriers, Miniature
Poodles, Pomeranians, Parson Russell Terriers, Papillons, Keeshonds, Samoyeds,
Chihuahuas, Cairn Terriers, Maltese, Toy Poodles, West Highland White Terriers,
Dachshunds, and mixed breeds.
Cocker
Spaniels, German Shepherds, Golden Retrievers, and Labrador Retrievers are
believed to be at decreased risk of CaOx stones.
Conventional
veterinary practitioners tend to consider calcium oxalate stones irreversible,
unaffected by diet or medical therapy, and untreatable except by surgery. They
may attempt to remove small bladder stones by flushing the bladder with sterile
saline, or perform shock wave or laser lithotripsy (processes that break stones
into small pieces that can be flushed out or excreted in the dog’s urine).
Uroliths
pose a more serious problem for male dogs than females, because their urine
travels through a hollow bone (os penis) that surrounds the urethra within the
penis. The bone cannot stretch or expand to accommodate a stone traveling
through it, and obstructions readily result.
For males
with recurring stones, a surgical procedure called urethrostomy sends urine on
a new path, avoiding the os penis. The urethrostomy creates a new urinary
opening in the scrotum area. This type of surgery cannot be performed unless
the dog is neutered; if he is intact, he can be neutered at the time of the
urethrostomy.
In up to
60 percent of conventionally treated patients, calcium oxalate stones recur
within three years. In dogs with Cushing’s Disease (hyperadrenocorticism) or
excessive calcium in the blood (hypercalcemia), both of which predispose dogs
to CaOx stones, the recurrence rate is faster. It’s important to treat these
underlying causes, if found, to help prevent recurrence. The recurrence rate
among Bichons is higher than for any other breed.
Calcium
oxalate crystals are of concern, but their presence doesn’t necessarily mean
your dog is at risk of forming stones. Crystals are significant only if found
in fresh urine. Crystals that form when urine is refrigerated or analyzed more
than 30 minutes after collection may be incidental and not indicative of a
problem. Dogs with calcium oxalate crystals in fresh urine should be monitored,
and if the finding continues, steps should be taken to reduce the risk of stone
formation, particularly in breeds most commonly affected.
Death
sentence to discovery
In 1997, Molly McMouse, a 14-year-old Lhasa Apso belonging to Leslie Bean of
Houston, Texas, was diagnosed with very dense, inoperable calcium oxalate
stones affecting both kidneys. Bean owned three more Lhasas – 15-year-old
FuzzerBear, 13-year-old Peepers, and 11-year-old CB Wigglesworth – who were closely
related to Molly. Fearful that her other dogs could be afflicted by the same
condition, Bean had them tested, and was shattered when each received the same
diagnosis.
 Leslie Bean and FuzzerBear. |
“My
husband and I were told that oxalates only proliferate in size and number,” she
recalls, “and that as the calcification of their kidneys increased, all four of
our dogs would die, probably within six to nine months.”
At the
time, Bean was founding director of patient advocacy at the University of Texas
MD Anderson Cancer Center, a position that helped her contact medical experts
of every description. She checked with veterinarians, veterinary researchers,
and directors of veterinary schools and laboratories around the country, only
to receive the same sad news from all.
“Every
one of them said these stones cannot be dissolved,” she says. “They all felt
bad about it, but they agreed that the prognosis for my dogs was hopeless.”
Bean’s
Lhasas had been on a premium, holistic food, but after their diagnoses, at the
recommendation of their veterinarians, Bean put them on a low-protein,
low-phosphorus, low-sodium prescription diet. The dogs disliked the new food
and their to-the-floor show coats rapidly dulled.
At that
point, Bean says, “I accepted the fact that my dogs were going to die but I
wanted to make their final months as terrific as possible.” Tossing the
prescription food, she began feeding fresh foods such as lamb and peas, chicken
and rice, and beef and broccoli. “I figured if they had so little time, they
were damned well going to enjoy what they ate,” she says, “and they loved it. I
can still see them dancing with joy when I carried their bowls to their places.
Literally within two weeks they began acting more energetic, looked younger,
had a spring in their step, and their eyes were clearer. Their coats looked
better, too, and we soon had to cut almost an inch in length from each dog
every month. Although that is common in young Lhasas in show coat, the rate of
growth slows with age, so this was a really noticeable difference.” Because
oxalic acid forms strong mineral bonds that can become calcium oxalate crystals
and eventually CaOx stones, Bean speculated that low-oxalate foods might help
prevent the stones’ formation (see “Oxalates in food,” page 9), and she made
those ingredients the foundation of her dogs’ menus.
Protein
In the past, diets restricted in both protein and phosphorus were thought to
reduce the risk of calcium oxalate formation. Studies found, however, that
dietary phosphorus restriction increased calcium absorption and the risk of
calcium oxalate formation, while higher levels of dietary protein reduced the
risk of uroliths. Current recommendations for dogs prone to forming CaOx
stones say that diets should not be restricted in protein, calcium, or
phosphorus.
In
February 2002, The American Journal of Veterinary Research published a study
conducted at the University of Minnesota College of Veterinary Medicine’s
Minnesota Urolith Center that compared dietary factors in canned food with the
formation of calcium oxalate uroliths in dogs, with surprising results. Canned
diets with the highest amount of carbohydrate were associated with an increased
risk of CaOx urolith formation. Contrary to commonly accepted beliefs, the
study concluded that “canned diets formulated to contain high amounts of
protein, fat, calcium, phosphorus, magnesium, sodium, potassium, chloride, and
moisture and a low amount of carbohydrate may minimize the risk of CaOx urolith
formation in dogs.”
In
contrast, Hill’s Canine u/d, often prescribed for dogs prone to forming CaOx
stones, is low in protein, calcium, phosphorus, magnesium, and potassium.
At the
beginning of her nutritional experiment, Bean reduced her dogs’ protein levels
so much that they began to lose muscle mass. “After much research, analysis,
and discussion with my veterinarians,” she says, “I increased their protein
levels to 33-40 percent of the total volume of food. They quickly regained
their lost weight and muscle, and there were no further problems with muscle
loss.”
As Bean
discovered, it’s very important not to reduce protein too much. Even the most
severely phosphorus-restricted diets for renal failure recommend feeding a
minimum of 1 gram of protein per pound of body weight daily.
Recheck
As the Lhasas continued to thrive, their primary veterinarian, Jane Milan,
encouraged Bean to return them for another ultrasound test to the veterinarian,
a specialist in internal medicine, who had first diagnosed them. “I just didn’t
want to hear bad news,” says Bean, “so I kept putting it off.”
Eight
months after their diet change and past or near their predicted death dates,
she made the appointment. “I was really nervous,” she says. “They looked
terrific, but I had no way of knowing what was going on inside them. And the
vet was with them for an unusually long time, which made me even more anxious.”
Finally the somber-looking veterinarian returned to the waiting room carrying
two of the dogs and said, “I don’t know how to tell you this.”
Bean
assumed that her other two dogs had died during their ultrasound tests and she
nearly fainted, but the vet’s good news revived her. The calcium oxalate stones
that had been ticking time bombs were nowhere to be found. That’s what caused
the long delay – he could not at first believe his test results. “The two older
dogs still had five tiny stones,” she says, “but they had shrunk to the size of
pin-dots, and they soon disappeared.”
Despite
the kidney damage already caused by their calcium oxalates, each of the already
senior Lhasas lived several more years. FuzzerBear died at age 19, the other
three lived to be 18, and frequent check-ups showed all four to be completely
free from calcium oxalate stones for the rest of their lives.
At the
suggestion of their veterinarians, Bean continued to study canine nutrition and
assembled a set of guidelines that described her dogs’ regimen.
“I am not
a veterinarian licensed to practice veterinary medicine in any state and make
no claims or representations as such,” Bean reminds everyone. “I am simply a
pet owner whose dogs suffered from intractable problems. I developed
FuzzerFood, named for Fuzzerbear, based upon the independent research I
conducted to help my own dogs. My discoveries are not intended to be veterinary
advice, nor are they a drug, biologic, or other therapeutic or diagnostic
substance or technique designed to replace a consultation with a qualified
veterinarian.”
She
recommends that owners of dogs with calcium oxalate stones work closely with
their veterinarians, beginning with a baseline ultrasound, complete blood
panel, and urinalysis. “Start now if you have not already,” she suggests, “to
maintain records of blood work and urinalysis reports as well as your own notes
as you go.”
Water,
the key ingredient
The most important thing you can do for a stone-prone dog is increase fluid
consumption and opportunities to urinate. Urine becomes concentrated when
insufficient fluids are consumed or when dogs are not able to relieve
themselves and have to hold their urine for long periods. And concentrated
urine contributes to supersaturation with minerals that can precipitate into
crystals and lead to stones.
One way
to encourage dogs to increase their water consumption is to add salt to their
food, but salt is controversial when it comes to calcium oxalate uroliths.
Increasing dietary salt encourages the kidneys to excrete more calcium, raising
urinary calcium levels.
One might
predict that increased sodium would therefore lead to increased calcium oxalate
formation, but that isn’t necessarily true. In a 2003 study, dogs were fed dry
diets containing varying amounts of sodium. The diets that contained 300 mg
sodium (about ⅛ teaspoon of salt) per 100 calories significantly reduced
urinary calcium oxalate supersaturation over diets containing 60 mg or even 200
mg sodium per 100 calories. Increased fluid consumption resulting from the
thirst generated by additional salt probably offset the increase in calcium
excretion. A human retrospective study published in 2009 concluded, “Increasing
urine sodium does not appear to increase the risk of calcium oxalate
nephrolithiasis (kidney stones).”
Bean,
however, does not add salt to food. The majority of human studies indicate that
adding salt is inadvisable, and many who elected to apply the FuzzerFood
regimen for their own dogs were unsuccessful in attempts to dissolve or prevent
recurrence of calcium oxalate stones when they departed from the guidelines
Bean developed for her own dogs.
You can
help your dog drink more by providing fresh water in clean dishes in several
locations; changing the water frequently; adding small amounts of tuna water,
salt-free or low-sodium broth, a favorite juice, or other flavoring agent to
drinking water in addition to offering plain water; adding water to food;
offering ice cubes as treats; using a pet water fountain to provide
continuously filtered fresh running water; offering water at every opportunity;
and carrying water and a portable bowl while hiking or traveling.
What type
of water should you use? Bean prefers steam-distilled water because it contains
no minerals that might combine with excess oxalic acid. Physicians she
consulted with told her that both hard and soft water may increase the risk of
calcium oxalate formation. Reverse-osmosis water filters remove 95 percent of
minerals, making RO-filtered water nutritionally similar to distilled water.
Not all
minerals in water contribute to kidney or bladder stones. In several studies
conducted in the 1990s, human patients who formed calcium oxalate nephroliths
drank a French mineral water containing high levels of calcium (202 parts per
million) and magnesium (36 ppm). Nearly every risk factor for calcium oxalate
nephroliths improved significantly. The same patients also drank local tap
water and mineral water with low calcium/magnesium concentrations, neither of
which improved the measured risk factors. The researchers concluded, “The risk
of calcium oxalate stone formation can be significantly reduced by consumption
of mineral water which is rich in calcium and magnesium.”
Other
research on the effects of hard and soft water on urolith formation has shown
mixed results regarding risk, possibly due to variations in mineral content and
ratios, along with factors such as whether the water was given with or between
meals. For this reason, distilled water may be safest, particularly for dogs
with kidney stones or recurrent bladder stones.
Getting
extra water into your dog is only part of the urolith-prevention strategy. Just
as important is the frequent release of urine. Give your dog many opportunities
to go outside during the day. If your dog is indoors alone or crated for hours
each day, find a way to create a convenient elimination area using plastic,
newspapers, towels, a patch of sod, or whatever you can devise to keep your dog
from having to hold her urine for long periods.
Urinary
pH
Calcium oxalate stones form in urine that is acidic, typically measuring
between 5.0 and 6.5 on the pH scale. Calcium oxalate crystals are generally not
sensitive to urinary pH, but marked acidification that induces metabolic
acidosis can promote calcium oxalate stone formation due to increased urinary
calcium concentration.
A common
recommendation for dogs prone to forming calcium oxalate stones is to alkalize
the body with foods or medications to bring the urinary pH closer to 7, which
is neutral. Alkalizing the urine will not cause existing stones to dissolve but
may help prevent new stones from forming. It’s important not to try to alkalize
the urine too much, as this can lead to the formation of calcium phosphate
stones.
You can
monitor your dog’s urine by holding a pH test strip in the stream or by
collecting urine in a paper cup or clean dish for testing.
But don’t
be surprised if your dog’s urinary pH stays where it is. Leslie Bean describes
her careful monitoring of her dogs’ urinary pH as a source of discouragement.
“I thought that unless I could bring their pH higher, their stones would
increase,” she says. “To the contrary, not only did they not increase, the
stones dissolved. I learned that the key is to monitor the pH and know where
you are, but not to panic if the urine stubbornly remains more acidic than you
would like.”
Oxalates
in food
Oxalic acid is found in both plants and animals, with plants containing higher
levels. It forms strong bonds with sodium, potassium, magnesium, and calcium,
creating oxalate salts. The term “oxalate” usually refers to a salt of oxalic
acid, one of which is calcium oxalate. Sodium and potassium oxalate salts are
water-soluble, but calcium oxalate is not, and it is what forms CaOx uroliths.
Interest
in low-oxalate diets has increased recently because of possible links between
oxalates and human kidney stones, arthritis, fibromyalgia, female vulvar pain,
autism and other pervasive developmental disorders, and chronic inflammation.
As a result, there is growing demand for accurate data on the oxalate content
of foods. When Bean began her research 13 years ago, much of the information
published about this subject was quite old. Eventually she found a small
booklet published by the University of California at San Diego, “Oxalate
Content of Select Foods,” which featured more current data and gave her a list
of foods to include and avoid.
Today,
the Oxalosis and Hyperoxaluria Foundation publishes an up-to-date list of foods
and their oxalate content. Based on research from 2008 and revised as new
figures become available, this report divides foods into very high, high,
medium, and low levels of oxalates according to serving size (see “Oxalate
Content of Various Foods,” next page). The foods in Group 1 (very high-oxalate
foods) are best avoided by dogs prone to calcium oxalate stones. Group 2
(high-oxalate) foods should also be avoided.
Group 3
foods have moderate oxalate levels. They can be fed in moderate amounts as long
as calcium is also given with the meal. Group 4 (low-oxalate foods) are “green
light” ingredients, and can be fed in any quantity, though they should still be
combined with calcium. See the complete list, available through the Oxalosis
and Hyperoxaluria Foundation, for information about additional foods, including
herbs, spices, combination foods, and beverages.
Some
websites and publications incorrectly list meat, liver, other organ meats,
shellfish, cheese, yogurt, broccoli, sardines, cherries, brussels sprouts,
olives, and strawberries as dangerous for CaOx-sensitive dogs, based on
outdated information. All of those foods are actually low in oxalates.
Designing
the menu
Because it’s difficult to find commercial foods made without ingredients that
are problematic for dogs prone to CaOx stones, home-prepared diets may produce
the best results. For those who already feed a home-prepared diet to their
dogs, the adjustments are simple. For those who are new to dog food
preparation, designing an effective menu need not be complicated. Your dog’s
food can be prepared along with your own meals or made in advance and
refrigerated or frozen in single portions for later use.
Start by
feeding different types of meat, poultry, eggs, fish, and dairy in order to
provide a variety of flavors and nutrients. The food Bean feeds her dogs is
about 40 percent protein by volume, but higher protein levels work well for
many dogs. The rest of the diet should be low-oxalate grains and/or vegetables.
While
Bean doesn’t include organ meats in her FuzzerFood guidelines, adding ½ ounce
(about 1 tablespoon) of liver per pound of other foods will add valuable
nutrients to a home-prepared diet.
Meat can
be ground, cut into cubes, or served in a single piece, assuming your dog
doesn’t have problems chewing. It can be fed raw or cooked. Because CaOx dogs
on raw bone-based diets have continued to form stones, the FuzzerFood regimen
does not include bones. Freeze-dried liver and similar dog treats are
appropriate for training and special occasions. Avoid treats that contain
high-oxalate ingredients, and factor treats into the daily food allotment of
overweight dogs.
 Getting your dog to drink more water is important if your dog has (or used to have) any type of kidney or bladder stones. Provide several sources of fresh, clean water, especially if you have more than one dog. |
Boiling
vegetables in water greatly reduces their oxalate content, while steaming
reduces levels slightly. Of course, boiling reduces nutritional content, so
it’s a trade-off. When you feed Group 3 (moderate-oxalate) vegetables, consider
giving smaller amounts raw and larger amounts cooked. Adding digestive enzymes
to food at serving time helps replace enzymes destroyed by heat.
Most
10-pound dogs need less than 1 cup of food by volume, while dogs weighing 50
pounds may need closer to 3 cups per day. Bean’s Lhasas maintain their 12- to
14-pound body weight on slightly more than 1 cup per day. The amount to feed
will vary according to your dog’s activity level and the amount of low-calorie
vegetables in the diet. Because key supplements should be given twice a day
with food, consider feeding breakfast and dinner rather than one meal per day.
Calcium
In the past, calcium was thought to be a risk factor for the formation of
calcium oxalate stones. Later studies found, however, that calcium binds
oxalate and thus actually reduces the risk of calcium oxalate stones when given
with meals.
When she
spoke with urologists who deal with human kidney stones, Bean learned that
supplementing homemade food with calcium citrate neutralizes oxalates in urine,
so she began giving it to her dogs with meals while avoiding all other mineral
supplements. “Citrate is an important natural inhibitor of calcium oxalate
stones,” she says. “When calcium citrate is combined with food at mealtime, it
helps absorb and bind excess oxalic acid in the gut. This bound oxalate cannot
be absorbed and is excreted through the feces. This means that it does not get
into the bloodstream or kidneys to cause stones.”
Pure
calcium citrate powder is inexpensive and easy to use. Bean adds 300 to 350 mg
of NOW brand Vegetarian Powdered Calcium Citrate to each 8 ounces (½ pound) of
fresh food to balance the diet’s calcium:phosphorus ratio. Calcium citrate
should only be added to homemade diets, or to the fresh portion of a combined diet,
as commercial diets should already contain the right amount of calcium (though,
unfortunately, they rarely use calcium citrate).
Supplements
For more than 40 years, the medical literature has reported on the success of a
simple nutritional therapy for the prevention of calcium oxalate stones in
humans using magnesium and vitamin B6. In studies published in The American
Journal of Clinical Nutrition, The Journal of the American College of
Nutrition, and other medical journals since 1967, patients with longstanding,
recurrent calcium oxalate kidney stones received 200, 300, or 500 mg magnesium
oxide with or without 10 mg pyridoxine (vitamin B6) daily for five years or
more, during which their stone formation fell by more than 90 percent. When
measured, their urine increased its ability to keep calcium oxalate in
solution.
Because
vitamin B6 deficiencies can contribute to an increase in oxalate production,
many veterinarians prescribe this vitamin for dogs prone to CaOx stones. Severe
vitamin B6 deficiencies may result from genetic disorders. Vitamin B6 is
available as an oral supplement or by injection. Follow label directions or, if
using a human product, give ¼ of the total dose for each 25 pounds of body
weight.
A
B-complex supplement provides all of the needed B-family vitamins. Give 50 mg
twice per day to dogs weighing 50 pounds or more, and one-fourth or half that
amount to smaller dogs. The FuzzerFood regimen includes Omega-3 fish or salmon
oil, a B-complex vitamin, and vitamin E, with optional CoQ10, magnesium,
glucosamine, digestive enzymes, and probiotics.
Magnesium
can have a laxative effect, so begin at the low end of the range, which is 3 to
5 mg per pound of body weight per day, divided into morning and evening doses
and given with meals. Magnesium supplementation is contraindicated for dogs in
renal failure, so if that is your dog’s condition, use this under your
veterinarian’s supervision only as long as there are stones, then discontinue.
Bean does
not use either vitamin C or vitamin D (including cod liver oil, which contains
vitamin D) because vitamin C is reported to convert to oxalate, thus possibly
increasing the risk of stone formation, and vitamin D promotes calcium
absorption, which leads to increased urinary calcium.Most multi-vitamins
contain vitamins C and D, so it’s important to read labels.
Supplements
manufactured for human consumption come in a wider variety than do veterinary
supplements, making it easier to find human products that avoid these
ingredients. Adjust the recommended human dose for your dog by weight.
Some
researchers have found that glucosamine supplements, which are commonly used
for arthritis, may help prevent calcium oxalate crystals from adhering to the
bladder wall. While this treatment is still speculative, glucosamine is safe to
give and may be helpful in preventing CaOx bladder stone formation.
When Bean
asked Traditional Chinese Medicine veterinarian Cory Stiles, DVM, for advice
from that perspective, Dr. Stiles recommended Lysimachia-3, a traditional
Chinese blend of three herbs, Jin Qian Cao or Desmodium, Hai Jin Sha or
Lygodium Spores, and Ji Nei Jin or Gallus, which is designed to treat human
digestive disorders, gall stones, and kidney stones.
“Lysimachia-3
comes in tablets,” says Bean, “which we crushed and mixed with food, or the
tablet can be placed in a small amount of low-fat cream cheese, or the dog can
simply be ‘pilled’ by putting it down the throat. My dogs had no objection to
having these tablets crushed and mixed with their food, and Lhasas are notoriously
picky.” Dr. Stiles’ recommended dose is 1 tablet per 25 pounds body weight
given twice daily until stones are dissolved. Then give Lysimachia-3 daily for
another month, then start using it every other day, then every three days, and
if all looks good, dose it three times per week every other week, and finally,
daily for one week out of every four to six weeks.
Preventive
medical treatment
Potassium citrate is a nutritional supplement that increases citrate levels in
the urine, attracting calcium away from oxalates. When calcium binds to
citrate, the resulting calcium citrate tends to remain dissolved instead of
precipitating out as a mineral deposit. Potassium citrate also has an
alkalizing effect on the urine, which can help to prevent the formation of
calcium oxalate stones, though it won’t dissolve existing stones. High blood
potassium levels are dangerous, so a veterinarian’s supervision and follow-up
blood tests are recommended when using potassium citrate. This supplement
should usually not be given when dietary changes alone maintain the urine’s pH
at 6.5 or above.
Calcium
citrate achieves the same goals of alkalizing urine and binding oxalates
without the risk of elevated potassium that can be posed by potassium citrate.
That’s why Bean considers calcium citrate a better option for her dogs’
homemade diets.
Dogs who
continue to form stones despite other steps to minimize risk may be prescribed
hydrochlorothiazide, a thiazide diuretic, to increase the amount of urine
produced while reducing urinary calcium oxalate saturation.
The
stress connection
In addition to good food and ample water, dogs need a stable home life, active
exercise, and interesting activities. Some researchers speculate that stress
plays a role in the development of kidney and bladder stones. When changing
your dog’s diet, do what you can to keep the introduction of new foods fun and
stress-free. Fortunately, most dogs love fresh food. Just as importantly, do
what you can to relax and let go of the stress that concern about your dog’s
health brings to your own life. The more you and your best friend enjoy each
other’s company with play, exercise, and shared quiet moments, the better
you’ll both feel.
Next
month: The final installment of our bladder/kidney stone series examines
cystine, calcium phosphate, silica, and ammonium urate or uric acid uroliths.
CJ
Puotinen is the
author of The Encyclopedia of Natural Pet Care and other holistic health books.
She lives in Montana, and is a frequent contributor to WDJ.
San
Francisco Bay Area resident Mary Straus has spent more than a decade
investigating and writing about canine health and nutrition topics for her
website, DogAware.com.
Read More on These Topics
Comments (0)
Be the
first to comment on this post using the section below.
Add your comments ...
Top of Form
northernwitch-
- Number of posts : 11031
Location : Toronto, Ontario -
Re: Calcium Oxalate - what do you know?
Renee 3/30/2012, 1:14 pm
Thanks Blanche. I actually already read that article (I subscribe to WDJ). I read it last night, and figured I will re-read it again soon, just so I can absorb things.
I was hoping I would get some personal insight from those that have dealt with these stones.
I was hoping I would get some personal insight from those that have dealt with these stones.
Renee-
- Number of posts : 5694
Location : Anchorage Alaska -
Re: Calcium Oxalate - what do you know?
northernwitch 3/30/2012, 1:16 pm
What I can tell you is that there seems to be a higher incidence of stones with dogs that have liver issues. Not sure if that's an issue for your foster or not.
I wish I had more to offer you, but this is about the best I've found. I thought you had read it and you had. But it's useful for others who may be struggling with this.
I wish I had more to offer you, but this is about the best I've found. I thought you had read it and you had. But it's useful for others who may be struggling with this.
northernwitch-
- Number of posts : 11031
Location : Toronto, Ontario -
Re: Calcium Oxalate - what do you know?
Renee 3/30/2012, 1:22 pm
northernwitch wrote:What I can tell you is that there seems to be a higher incidence of stones with dogs that have liver issues. Not sure if that's an issue for your foster or not.
I wish I had more to offer you, but this is about the best I've found. I thought you had read it and you had. But it's useful for others who may be struggling with this.
Totally true - it is useful, especially for someone that may not have the information.
We did a full blood panel, and everything was normal. So, as far as I can tell, there are no contributing factors. Now, due to his unique body structure, and the fact that I truly do believe excreting is painful for him, I am not surprised that he would form a stone, but I would have expected them to be struvites in conjunction with an infection. However, that is not the case.
What troubles me is the high incidence of re-occurrence and that they seem harder to manage than struvites.
Renee-
- Number of posts : 5694
Location : Anchorage Alaska -
Re: Calcium Oxalate - what do you know?
northernwitch 3/30/2012, 1:55 pm
Oxalate are much harder to manage than struvites, in my experience. We are getting in a liver girl who has had multiple surgeries for stones and I'm anticipating a fair bit of struggle with her. I do think that holding urine doesn't help even with oxalate, but seems more an issue with struvites.
Wish I could offer more, Renee.
Wish I could offer more, Renee.
northernwitch-
- Number of posts : 11031
Location : Toronto, Ontario -
Page 1 of 1
Permissions in this forum:
You cannot reply to topics in this forum|
|
|
