Management of Bichons with Urinary Stones

Management of Bichons with Urinary Stones

It has long been recognized that some Bichons Frises have a predisposition to formation of urinary stones (uroliths). This condition is known as urolithiasis. There are several types of stones that can form in the bladder, with struvite (also called magnesium triple phosphate or ‘infection’ stones) and calcium oxalate being the most common in Bichons. The most important preventative for stone formation is free access to fresh water. For a dog predisposed to stone formation, there are other considerations as well. This article is intended to provide the pet owner with a better understanding of the prevention and treatment of urinary stones. Good veterinary treatment is the most reliable resource for the ongoing care of your dog. You may wish to copy this article for your veterinarian.

The Bichon Frise Club of America, Inc. sought input from Carl A Osborne DVM, PhD in preparing this material. Dr. Osborne, Professor at the College of Veterinary Medicine, University of Minnesota, is considered a leading authority on canine uroliths. We are grateful to him and to his team at the Minnesota Urolith Center for their assistance in making this information available. For more information, you and your veterinarian will be aided by the book ‘The ROCKet Science of Canine Uroliths’. You will find details in the article below.

And now, please carefully read the following article, prepared by Dr. Osborne and his staff. At the end of the article, there are several paragraphs about Bichon health that need to be considered as a part of the total picture in treating Bichons with bladder infections and stones.

The Bichon Frise appears to be at increased risk for some types of bladder stones (or uroliths). In medical terminology, this condition is called urolithiasis (uro = Greek meaning urine, lith = Greek meaning stone, iasis = a process or condition).

What are uroliths?

Several different minerals can form stones within the urinary tract of dogs, including magnesium ammonium phosphate (struvite), calcium oxalate, ammonium urate, cystine, calcium phosphate and others. In uroliths, these minerals may occur singly or in combination.

Key Point: Knowledge of the mineral type(s) comprising the stones is recommended to
determine the best treatment and preventative therapy.

Currently the two most common minerals found in uroliths formed by the Bichon are magnesium ammonium phosphate (struvite) and calcium oxalate. In the past decade, an increased occurrence of calcium oxalate urolithiasis has been recognized in several breeds of dogs and several breeds of cats. The causes associated with this increased occurrence of calcium oxalate uroliths are currently under investigation. To date, studies indicate that multiple genetic, environmental, dietary and drug related factors may be involved.

Of the uroliths submitted in 1998 to the Minnesota Urolith Center for analysis from the Bichon Frise breed, 51% were struvite, 37% were calcium oxalate and the remaining 22% were composed of other minerals. Calcium oxalate is more likely to form in males, struvite is more likely to form in females. In a recent survey of the Minnesota Urolith Center database, 10% of male Bichons formed struvite uroliths, 80% of male Bichons formed calcium oxalate uroliths. Conversely, 50% of female Bichons formed struvite uroliths, 36% of female Bichons formed calcium oxalate uroliths. These percentages refer to stones removed from Bichons and therefore they do not apply to all Bichons.

Key Point: Calcium oxalate uroliths are increasing in occurrence. Multiple factors are associated with this change in prevalence of mineral types in stones and studies are underway to identify risk factors.

Struvite uroliths

In dogs, struvite uroliths are primarily associated with a diagnosis of infections caused by urease producing bacteria. Although other factors may predispose a dog to struvite uroliths, bacterial infections with staphylococcus and other urease producing pathogens are clearly the most important. Once a diagnosis of struvite uroliths has been made, at least 3 therapeutic options are present.

1. Medical and dietary dissolution of uroliths
2. Non-surgical procedures for removal of uroliths
3. Surgical removal of uroliths

1. Medical and dietary dissolution consists of feeding a special diet, available from veterinarians, along with treatment with an appropriate antibiotic. Your veterinarian will perform a urine culture to determine which antibiotic will most likely be effective in treating the infection. These antibiotics should be administered until the stones are completely dissolved. The time required for medical dissolution is dependent on the number and size of the stones and compliance with dietary and antimicrobial treatment by the owner. Some have been dissolved within a few weeks, whereas others may require up to 2 months or more.
2. Non-surgical procedures have been developed to remove stones small enough to pass through the urethra. Best results may be obtained from veterinarians who have experience with these techniques.
3. Surgery consists of removal of uroliths from the urinary tract.

Once struvite uroliths are dissolved medically or removed surgically, prevention of the urinary tract infection will prevent recurrence. Prevention of urinary tract infections may require periodic urinalysis and urine culture. Periodic radiographs (i.e. x-rays) may also be indicated. Antibiotics and/or a diet designed to lower urine pH and restrict certain minerals may be recommended on the basis of these test results.

Key Point: If the infection can be eradicated, struvite uroliths will not form or recur even if secondary factors persist.

Calcium oxalate uroliths

Once a diagnosis of calcium oxalate uroliths has been made, at least 2 therapeutic options are present:

1. Surgical removal of uroliths
2. Non-surgical procedures for removal of uroliths (Note that calcium oxalate uroliths cannot yet be dissolved by medical treatment)

1. Non-surgical procedures have been developed to remove stones small enough to pass through the urethra of the pet. (Best results may be obtained from veterinarians who have experience with these techniques.)
2. Surgery consists of removal of uroliths from the urinary tract.

Once calcium oxalate uroliths have been removed, urinalysis and urine culture should be a part of follow-up visits. Periodic x-rays may also be indicated. Owner compliance with feeding special diets designed to minimize risk factors associated with calcium oxalate urolith formation will help prevent recurrence. In general, certain drugs should be avoided including corticosteroids, furosemide, ascorbic acid (vitamin C), vitamin D, and acidifiers because they increase the risk of calcium oxalate urolithiasis.

Key Point: It is not yet possible to dissolve calcium oxalate uroliths by dietary management.
However, compliance with feeding special diets and avoiding use of certain drugs will minimize risk factors known to be associated with calcium oxalate urolith formation.

What about water sources?

In a case-controlled epidemiological study performed at the University of Minnesota, the source of water ingested was not found to be a risk factor for formation of calcium oxalate uroliths. However, the volume of water ingested usually plays a significant role. By increasing water consumption, the urine concentration of urolith-inducing constituents will be decreased or diluted. We highly recommend feeding a canned diet and providing ready access to fresh water at all times to increase water consumption and urine voiding. Both of these goals decrease the risk factors for urolith formation.

What about pH testing?

Ask your veterinarian about testing urine pH at home. Struvite uroliths tend to occur in alkaline urine. Calcium uroliths are associated with acid urine.

What about collecting urine samples?

Urinalysis is an important part of preventative therapy. Because external factors such as temperature, delay in sample analysis, evaporation of the sample, contaminated collection container, contaminants from hair or skin, and other factors may affect the urine, urine samples should be collected (preferably by the veterinarian) and evaluated as soon as possible.

Samples may also be collected at the veterinary hospital by a procedure called ‘cystocentesis’. A sterile needle is inserted into the bladder and a urine sample is withdrawn into a sterile syringe. This is the preferred method for collecting a urine sample for culture. Identification of crystalline material is best performed at the veterinary hospital.

Screening samples may be collected by the owner using a clean cup or container. These samples should be capped, labeled with the date and time collected, and taken promptly to your veterinarian for evaluation.

Key Point: For best results, fresh urine samples should be analyzed.

What about analysis of stones?

Any stones that are removed surgically or voided during urination should be evaluated by quantitative methods of analysis. Proper analysis of the uroliths is vital to successful treatment. Unfortunately most veterinary laboratories perform qualitative analysis which is a highly unreliable test.

Key Point: Have uroliths analyzed by quantitative analysis.

Veterinary laboratories qualified to perform quantitative analysis are:

Minnesota Urolith Center
Dr. Carl Osborne DVM, PhD, Director
Department of Small Animal Clinical Sciences
College of Veterinary Medicine
University of Minnesota
1352 Boyd Avenue
St. Paul, MN 55108
Lab Phone 612/625-4221

Urinary Stone Analysis Laboratory
Gerald V. Ling PhD, Director
College Of Veterinary Medicine
University of California-Davis
Davis, CA 95616
Lab Phone 530/752-3228

Where can my veterinarian get more information?

The Veterinary Clinics of North America ‘ Small Animal Practice

‘The ROCKet Science of Canine Urolithiasis’
Volume 29:1, January 1999
(Available from W. B. Saunders Publishing Company ‘ Phone 800/654-2452)

The following information is provided by BFCA to broaden your understanding of health problems that may occur in the Bichon Frise during treatment of bladder infections and stones. You and your veterinarian must work together to observe any developing conditions that may occur during treatment. As with humans, dogs can sometimes have more than one health problem. The information provided is intended to alert you to health concerns that you should watch for or to help you avoid having problems develop. As with stones, not all Bichons have these problems. The Bichon Frise is, for the most part, a healthy breed.

The owner’s first indication of a bladder infection or of stone formation may be the appearance of blood in the urine. Before that stage has been reached, the owner should be alert to frequent urination, ‘accidents’ in a female that is normally well-trained, excessive licking of the genital area and, in males or females, persistent straining to urinate. If they persistently strain to urinate but only pass small quantities of urine, they need immediate veterinary attention. The dog that seems to strain, passes a few drops and then passes a gush of urine has probably just passed a stone and needs to be seen. Dogs with a blocked urethra are a medical emergency because urine can back up into the system and lead to renal failure. The bladder can rupture and the bladder that has been stretched may lose muscle tone, making it difficult for this dog to empty his bladder completely even after the stones are removed from the urethra.

Water consumption is important in preventing and in treating uroliths. Bichons like their water FRESH. This means that you need to change the water often. In a multi-dog household, your Bichon may choose not to drink after the other animals have been drinking from a community bowl. You need to be aware of this idiosyncrasy and to see that the water is changed several times a day. You will also need to provide a hook-on bowl in the crate for any dog that is left in his/her crate for long periods of time.

Urination: The dog with stones should be encouraged to empty his bladder often because urine retention encourages crystals to form. Urine samples for screening should be collected first thing in the morning (before eating) and collected in a clean glass or plastic container. For the ‘modest’ dog that will not cooperate with holding the container in the appropriate area, try a sample cup (used by groceries and delis) secured in place with a hand towel or plastic wrap.

Compound stones can sometimes occur. The dog with both struvite and calcium oxalate stones should receive the diet for calcium oxalate treatment along with appropriate antibiotics for the infection that may be associated with struvite.

Good dental care is essential! For Bichons, with a history of early tooth loss and excess tartar buildup, adding water to dry food or feeding a canned diet increases the likelihood of gum disease. This means more stringent attention to dental care. Daily tooth-brushing, use of canine toothpaste, scaling at home and more frequent professional cleaning at a veterinary hospital becomes a part of the routine (and is recommended for all Bichons anyway). Gum disease can be a cause of systemic infections that could lead to bladder infections.

Allergies are a common problem in Bichons (and other white-coated dogs). Steroid medications are contra-indicated in the dog with calcium oxalate stones. There are other ways to deal with the allergic Bichon. You should see www.bichonhealth.org/HealthInfo/Allergies.htm for recommendations that allow you to cut back on or omit steroid use.

Furosemide (Lasix) is prescribed for heart conditions and other maladies. However, furosemide increases calcium excretion in urine, and is therefore a risk factor for calcium oxalate uroliths.

Diets that are high in fat (such as Hill’s Prescription S/D for treating struvite) are a risk factor for a metabolic condition called pancreatitis that occurs in Bichons. Dogs with a previous history of pancreatitis should be appropriately monitored. Discuss with your veterinarian the symptoms of this condition so that you will be prepared to recognize symptoms should they occur. There may be another diet that can be substituted or pancreatic enzymes may be needed if the condition develops. (Many Bichons have been treated with this diet without a problem.)

Dietary treats may contain substances that are to be avoided so use only prescribed diet kibble or an approved substance for treats. This includes any treats used for obedience or show-ring training. Bichons will respond well to positive reinforcement, so a kind word or pat may suffice ‘ or train with a clicker. To see a list of foods that should be avoided in the dog with calcium oxalate stones, scroll down.

Final word: Bichons with stone formation are not candidates for breeding.

We encourage you to use this information while working closely with your veterinarian to achieve your Bichon’s improved health. We again express our appreciation to the Minnesota Urolith Center and to Dr. Osborne and his associates for their cooperation in making this information available to you.

Risk Factors and Undesirable Associations:

Source:
‘The ROCKet Science of Canine Urolithiasis’.
Volume 29:1
January 1999
W. B. Saunders Publishing Company
pg.131

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