Tuesday, August 10, 2010

Something's Amiss if a Dog ....

OK, so no one read the last blog post. It can't be that no one knows where the film quotes are coming from. But just in case there are hundreds of you out there and you are just to shy to let me know what movie I'm rambling on about, today's post title is another hint.

I also purposely skipped dogs in last week's post about lower urinary tract disease. No, not because I think dogs are second class pets. It's just that their disease is actually easier to write about and the photos that I have are better, or at least more dramatic.

Now, dogs with lower urinary tract disease often have infections. These respond well to antibiotics. The diagnosis is made by clinical signs, (frequent urination other than marking by unaltered males), +/- blood in the urine, a urinalysis indicating infection or inflammation, and sometimes a culture. Simple UTIs (urinary tract infections) are more common in females than males, an anatomical issue not a sexist one, and should respond to a short course of antibiotics. Cure should be confirmed with a follow up urinalysis. UTIs that do not respond to treatment usually fall into one of several categories. 1. The antibiotic chosen was not appropriate for this specific infection due to bacterial resistance, solution, culture to get correct antibiotic sensitivity. 2. Antibiotic was appropriate, but not given for a long enough time or at the correct dose. 3. There is some sort of underlying problem causing the infection or the clinical signs that are interpreted to be an infection. These can be any of the following; bladder failing to empty completely due to anatomical defect or neurological problem, obesity causing anatomy problems leading to ascending bacterial infections, bladder tumors, or (if you peaked ahead) bladder stones.

This radiograph is a much better illustration than the cat photo from last week. Need I point out the mass of minerals in this poor dog's bladder. I hope not because I still haven't gotten around to the use of arrows in my photographs. (any hints on this would be greatly appreciated.)

Bladder stones in dogs are similar to urinary stones in most mammals. They are mineral concretions that form in the urinary tract. We do see calcification of the kidneys as well, but clinical kidney stones are less common than bladder stones in dogs. The most common stones historically were struvite stones. These phosphate based stones need a nidus to form, usually a bacteria and are therefor associated with UTIs. An important factor when talking about prevention. Struvite stones are usually smooth, yellow to tan colored little rocks. They tend to form in alkaline (not acid) urine but I have seen them look like anything and form in all sorts of urine. The only way to tell what type of stone the dog has is to get one and send it off to the lab. Now, in male dogs, there is usually only one way to get one, surgery. I have been lucky in females and have been able to get them to pee out a small stone that we can have analysed. The other cool thing about struvite stones is that they can be dissolved by diet. While the SO diet by Royal Canin will do this, I find that S/D (could that be for stone diet?) made by Hills does a great job. Struvite stones can be dissolved in about 1 month in most dogs. There is a catch for the guys tho. I don't like to try to dissolve stones in a male dog. The thing is, that before a stone dissapears, it becomes small. Small stones can pass out of the bladder and get stuck in the urethra, just above the os penis (penis bone) This can cause an obstruction, a true surgical emergency.

So for all you guy dogs out there, and you know who you are, your choice is surgery. Here's what came out of the bladder above.

Pretty impressive collection, huh? Now once the stones are out, if they turn out to be struvite, we do put the dogs on S/D just to make sure that we are good to go and that nothing else is forming. Then we put the pet on a maintenance diet and monitor the urine every month. What are we looking for? Infection. Remember, these stones need a nidus of bacteria to form, so if we can catch the UTI early, we can prevent the struvite stones from forming. The thing we have to be careful about tho is the other end of the spectrum, stone wise. We used to try to promote an acid urine, either by diet manipulation or by adding acidifiers to the diet to prevent these stones from forming. That's when we started to see an increase in the number of oxylate stones in our canine patients. These stones cannot be dissolved by diet, do not need infection to form, and must be removed surgically in males and females. They are rough surfaced and can stick to the lining of the bladder. They can be difficult to remove and I can only assume that they are quite painful. Once out, we usually use the Royal Canin diet to prevent them from coming back. This diet maintains a neutral ph so as not to encourage struvite stone formation and works by decreasing the precursors for stone formation in the bladder. Another new improved option is Hills C/D multicare, it does the same thing. I won't put another set of links to the website, just follow the ones above.

So the take home message is, re occurring bladder symptoms in the dog are not usually just repeated infections. Additional testing needs to be done to find out why the dog is having the problem, what the problem is, and what can be done to cure this episode and prevent future ones. It is an on going problem that can be managed very well with diet and follow up.

Oh, and if anyone thinks they know their stones, here's a little trivia question. What breed do you think has the greatest incidence of bladder stones in our practice. I'll give you a hint, nah, no hint, but I will give you a prize. First person that doesn't work at my hospital to leave the right answer as a comment will get a $10 gift certificate for some really outstanding pet food. Check it out at www.TheVetsChoice.com.


Dog Mama said...

I don't know my stones, but I'll take my guess: Bulldogs?

Keith Niesenbaum, VMD said...

Well, I have to say, you do know your dogs, but not your stones. I think that Bulldog is a good guess for any problem. Starting from the tip of their noses down to the curl of their tail, this is a breed with more man made problems than probably any other. Fortunately, bladder stones is not their biggest concern as abdominal surgery on a middle age bull dog would be stressful on the veterinarian, not to mention the patient.

Dog Mama said...

Can I ask you a question? There is a point though it might not seem like it:

Did you observe any correlation between this type of disease and fear tendencies?

Keith Niesenbaum, VMD said...

@ Dog mama. I'm not aware of any connections in dogs. By the way, I checked out your blog, nice posts. I retweeted (such a social networker I am) and will try to follow. Everyone should. Here's the link: http://dawgbusiness.blogspot.com/