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6 posts from October 2009

10/31/2009

Happy Halloween Story (complete with orange and black puppy!)

So, my friend Mark the park ranger was walking his Labrador, Aedan, in the woods when Aedan started sniffing the air in an agitated fashion and tugging hard on the leash. This was very unusual for him; Aedan is normally a really laid-back dog and it was obvious he was extremely concerned about something that he wanted Mark to know about. Mark let him off the leash and Aedan raced away with Mark following. As Mark approached the spot where Aedan had stopped, he could see from a distance that Aedan had found some sort of animal that was making all sorts of noise- normally Aedan does not get excited about the usual animals in the woods near where they live, such as deer and so on, so Mark knew this was different. Worried it might be a sick or rabid animal, he instructed Aedan to stay where he was and leave the animal alone; Aedan obediently hovered about three feet from what he had found.

When Mark arrived at the spot, he saw what (or shall I say who) Aedan was so worried about:

Brindle pup 2

Aedan had found an abandoned puppy! They were at least a mile from any home, near a dirt road, so it was apparent that someone had driven down the road and dumped this little girl in the woods.

Of course, she was desperately afraid and making all kinds of terrified noise but as soon as Mark wrapped in her in his sweatshirt and picked her up she calmed right down and was obviously thrilled to have been rescued.

Off she went to a warm house, good meal, and a cozy bed...thanks to Aedan the wonder Lab!

And that is the Happy Halloween story of the small orange and black puppy saved by a big black Labrador named Aedan.

Brindle pup 1 

Here is a picture of the hero, Aedan Dog, with his Halloween pumpkin:

Aedan with pumpkin

Of course, they all lived happily ever after!

10/30/2009

Inflammatory Bowel Disease in Cats (IBD)

As a veterinary internal medicine specialist, I have done my best to explain inflammatory bowel disease (IBD) to countless cat owners (and veterinary interns, and externs, and random people at dinner parties...). On many occasions I've said that I need write down my little spiel, so I can just let everyone read about it while I kick back and drink chai latte...just kidding about that part, but it is time to blog about this ubiquitous topic.

First of all, let me clear up one confusion: it's inflammatory bowel disease, not irritable bowel syndrome. I know you are forever hearing about people with IBS and how they should take this drug or eat that yogurt...what kitties get is entirely different and it is IBD, not IBS.

So what the heck is inflammatory bowel disease, in pets? What this term really means is that when a pathologist looks at a biopsy of that cat or dog's intestine under the microscope, the pathologist sees white blood cells that shouldn't be there. There are different types of inflammatory bowel disease, based on what kind of white blood cells are the culprits; the most common kind in cats is called (take a deep breath) "lymphocytic-plasmacytic inflammatory bowel disease". Don't panic - I can explain.

We all have lots of different kinds of white blood cells, whose main job is to fight infection. Some of the most common types are neutrophils, lymphocytes, plasmacytes, and eosinophils. So when a pathologist says that a cat has "lymphocytic-plasmacytic IBD", she means that under the microscope, she sees lymphocytes and plasmacytes lining the small intestines and/or the stomach.

Here's a really bad, very simplified drawing of a normal intestinal wall, and an intestine with lymphocytic-plasmcytic IBD:

IBD and LSA 004
IBD and LSA 005

Your next question is: why do the white blood cells come to the intestine? Good question, and the answer is that we don't really know. Probably there are different reasons in different animals. Whatever the reason, the intestinal immune system gets overexcited and sends all these soldiers (the white blood cells) to do battle and then the white blood cells lining the intestines make it hard for the GI system to function properly...so the cat loses weight (because he can't absorb nutrients effectively) or vomits, or has diarrhea, or doesn't want to eat, or any combination of the above.

Unlike most of the body, the intestinal immune system has to be like a bouncer at one of those hot clubs where everyone lines up - it has to really pick and choose about who gets in and who is rejected. In most of the body, anything foreign is bad and the immune system attacks and gets rid of the invader. For example, there should be no bacteria hanging around in the bladder, or the lungs. If there are, they get kicked out, hopefully. But if you think about it, the intestines are different. There are bacteria that normally live there, and also, if you're a cat, there are things like chicken, beef, and fish all hanging around. So the intestinal immune system has to be very selective: "OK, all you normal bacteria can stay, as long you behave and there aren't too many of you, but Mr. Giardia, you need to leave, and Ms. Salmonella, I'm not thrilled about you either...". We think what happens with inflammatory bowel disease is that the intestinal immune system gets confused, and starts seeing normal bacteria or food proteins as enemies that need to be evicted. 

I said that one of the things that might be pissing off the immune system is food proteins. That's called food intolerance or allergy. In some cases of IBD, a change to a hypoallergenic diet can help. A hypoallergenic diet is food that has very limited ingredients, of types that tend to be less allergenic, and generally composed of ingredients that the animal has never had before. So a cat who has been fed chicken and fish and beef might be switched to duck or lamb. When using a hypoallergenic diet, it's really important that it's made of a "novel protein" (a protein source that is new to the animal) and that there are no other protein sources in there. There would be no point to feed a venison diet, for example, that also had some chicken broth in it. It's also really important that the animal is not fed any treats or anything else that contain ingredients other than those in the diet. There is no point to have your cat on a hypoallergenic lamb diet but also give her a little piece of turkey once in a while, or chicken-flavored treats or medicine. 

Unfortunately, right now there is no accurate way to test for a food allergy. The only way we can really tell is to try feeding a novel protein diet and see if the animal improves. There are prescription novel protein diets, there are some being sold over the counter (read the ingredients carefully to make sure there is nothing extraneous in there!), or you can make a balanced homemade novel protein diet with the help of websites like www.petdiets.com.

OK, so we don't know exactly what causes inflammatory bowel disease in cats, but some theories include excess carbohydrates in the diet (like dry food), bacterial flora imbalances, food allergies, or infections (such as bacteria, viruses, or parasites). I hope that one day we understand the causes better, so treatment can be more specific, but right now we end up treating many cases of IBD in a somewhat similar fashion.

Before we talk about treatment, let's talk about diagnosis. This is a step that sometimes gets skipped, to the detriment of the cat. Signs of inflammatory bowel disease in cats are very nonspecific; one of the most common signs is weight loss, and other signs include vomiting, diarrhea, or poor appetite. These signs can all also be caused by plenty of other things, such as cancer, pancreatic inflammation (pancreatitis), liver disease, ulcers, parasites, etc. So it is very important to obtain a definitive diagnosis before jumping into treatment! Especially since treatment may involve strong drugs like corticosteroids, which you wouldn't want to give without a specific reason. 

One disease that can cause identical symptoms to IBD in cats is called "small cell lymphoma". This is a slow, low-grade type of intestinal cancer that is very treatable. It's essential to differentiate whether a cat has IBD or small cell lymphoma because the treatment regime is different. And cats with small cell lymphoma can live happily for years on proper treatment (my own cat lived almost five years with this disease and died at close to 18 from something else entirely). In small cell lymphoma, the intestines are infiltrated by the white blood cells called lymphocytes (similar to inflammatory bowel disease), except there are lots and lots of them and they are more invasive.

The question has arisen whether inflammatory bowel disease is a precursor to small cell lymphoma, i.e. whether some cats with untreated (or treated?) IBD may go on to develop small cell lymphoma; does IBD in some cases "morph" into small cell lymphoma? We aren't sure. We do know that small cell lymphoma if unchecked can turn into a more malignant cancer called lymphoblastic lymphoma, where the cat actually develops a tumor.

Some bad illustrations are below:

IBD and LSA 001
IBD and LSA 002
IBD and LSA 003

The bottom line is that it is crucial to accurately diagnose and properly treat feline inflammatory bowel disease and small cell lymphoma. This is generally done through a combination of ultrasound and biopsies. We usually do an ultrasound first, to evaluate the stomach and intestines, see which parts of the GI tract (if  any) look abnormal, evaluate all the other organs such as the pancreas, liver, and spleen, and see if something else entirely may be causing the cat's symptoms. On ultrasound, the intestines of a cat with inflammatory bowel disease may look perfectly normal, or they may be somewhat thickened or have abnormal layering (disproportionate thickness of particular intestinal layers). Some cats with IBD or small cell lymphoma may have enlarged lymph nodes near the intestines.

It's essential that a skilled clinician performs your cat's ultrasound; some more information is here.

If the ultrasound is most consistent with the cat's symptoms being caused by IBD or small cell lymphoma (these cannot be differentiated on ultrasound), then a biopsy is performed. This can be done in one of three ways: endoscopy, surgery, or laparoscopy. Each has pros and cons, and your vet or internist can help you decide which is best for your cat. Endoscopy is least invasive and least expensive, but the biopsies are smaller and cannot be taken from as many different parts of the intestine. Surgery tends to be very accurate as long as good biopsies are taken from different sections of the intestinal tract, but obviously is more invasive and costly. Laparoscopy (minimally invasive surgery) is available at some facilities, and allows good biopsies to be taken with smaller incisions than the incision required for surgical biopsies. Being an internist, I do a lot of endoscopy, but I counsel pet owners about the pluses and minuses of each method.

It is essential to obtain biopsies before any medication is initiated, because medication, particularly corticosteroids, affect our ability to ever get a definitive diagnosis. They will mask symptoms, cause temporary improvement even with cancer, and can change the appearance of biopsy samples. It is NOT a good idea to do what is sometimes called a "steroid trial", where the cat is given steroids to see if symptoms improve. The symptoms of almost anything will temporarily improve on steroids, and once the cat has been given steroids, our ability to obtain a true diagnosis is greatly hampered. The cat can really be harmed if this causes accurate diagnosis or proper treatment to be delayed.

What is the treatment for inflammatory bowel disease? And small cell lymphoma? For inflammatory bowel disease, it depends somewhat on the severity and type. Treatment may include hypoallergenic diet, certain antibiotics such as metronidazole (Flagyl) and/or corticosteroids such as prednisolone. In cases of inflammatory bowel disease, the corticosteroid is very slowly tapered down based on the cat's progress; for example a cat might be on 10 mg a day for 2-3 months, then 5 mg a day for 2-3 months, then 2.5 mg a day, and so on. Unfortunately, most cats on corticosteroids for IBD cannot get off the drug entirely without relapsing.

For small cell lymphoma. the situation is different. Corticosteroids are also used, but the dose is never tapered, unless necessitated by side effects or other health issues. Generally cats are left on the same high dose for the rest of their life, and luckily they seem to do fine with this regime. In addition, cats with small cell lymphoma are usually treated with a drug called Leukeran (chlorambucil), also for the rest of their life. For example, a cat might receive one 2 mg tablet of Leukeran every other day. The combination of prednisolone and Leukeran works very well long-term in many cats. You can see why it is so important to obtain a definitive diagnosis if possible; if you did not know a cat had small cell lymphoma and treated presumptively for IBD, as the corticosteroid dose was tapered, the cat would relapse or potentially develop the much more devastating cancer called lymphoblastic lymphoma.

Some cats with IBD or small cell lymphoma will become deficient in certain B vitamins, particularly cobalamin (B12) and folate. This occurs because the inflamed intestines cannot properly absorb these vitamins. It is easy to test for B12 and folate deficiencies; a blood test is drawn after the cat has not eaten for about 12 hours. This test is important for several reasons: one, if either vitamin is low, it is a good clue that the cat may have intestinal disease, and two, it is essential to treat a deficiency if one exists. I often perform a test called a feline maldigestion profile, which measures these vitamins as well as checking for a deficiency of pancreatic digestive enzymes (a deficiency of digestive enzymes can cause similar symptoms to IBD or small cell lymphoma).

One of the most important things to monitor in cats with GI disease is their weight; if they are responding well to treatment they should gain back their weight and then maintain it. I encourage cat owners to purchase a good scale and monitor their cat's weight at home; my favorite scale is the Redmon Electronic Weigh-To-Grow Baby Scale.

Phew! Well, there you have it in a nutshell: IBD is a disease frequently seen in cats, which should be definitely diagnosed before treatment, and for which we don't really know the cause. Hopefully one day the veterinary profession will know more about this incredibly common problem, and in the meantime now YOU know more about it than you did 10 minutes ago!

10/18/2009

Ultrasound for pets...what you should know

Diagnostic ultrasound for pets has been an incredible advance in veterinary medicine. The ability to use ultrasound to look inside the abdomen or chest of an animal means that we can often quickly and non-invasively investigate a host of different health conditions. But pet parents need to know some basic facts about ultrasound to protect their pets and ensure they truly benefit from this technology.

Ultrasound scans, also called sonograms, use high-frequency sound waves to form images of tissues within the body. This technology is similar to the sonar used by bats and ships at sea. The sound waves are reflected by the patient's tissues and these reflected sound waves are recorded and displayed as a visual image. This occurs in "real time", meaning that the images are immediately displayed on a screen, and events such as blood flow, heart beats, and gastrointestinal movement can be observed as they occur.

Abdominal ultrasound can be used to examine the liver, gall bladder, spleen, kidneys, bladder, prostate, uterus, ovaries, adrenal glands, stomach, and intestines. This means it can help us to pinpoint the cause of common pet health issues such as vomiting, elevated kidney or liver values on blood tests, abnormal urination, unexplained weight loss, and much more. We can also use ultrasound to look at some of the structures in the thorax (chest). We can't look inside the lungs, since ultrasound is impeded by air, but we can examine the heart and look for abnormalities such as fluid, enlarged lymph nodes, and tumors.

If your pet ever needs an ultrasound exam, it's crucial to ensure that it's done properly. An inadequate ultrasound can be worse than none at all, since it often leads to misdiagnosis, which can be very dangerous for your pet.The use of ultrasound in veterinary medicine has become very common but there are no regulations in place to ensure that your pet’s ultrasound is performed competently.

Ultrasound isn't magic; it takes training, skill, and experience for the operator to accurately locate and examine the various abdominal organs and tissues and to correctly interpret any abnormalities. Without adequate mastery, it can be very easy to misinterpret an ultrasound image—to mistake gas bubbles in the colon for bladder stones, to miss subtly enlarged abdominal lymph nodes, to overlook a localized intestinal thickening. Some organs can be very tricky to locate if the operator lacks proficiency; it is common for inexperienced individuals to miss the adrenal glands or pancreas, for example.

If your pet requires an ultrasound exam, it falls to you to ensure that the person performing the procedure has adequate training to do so effectively, since there are no standards currently in place in the veterinary profession. Anyone can buy an ultrasound machine and start using it on people’s pets, and the results of mistakes can be tragic.

The best way to protect your pet is to have the ultrasound exam done by a board-certified veterinary radiologist if possible . Radiologists undergo a lengthy residency program, during which they receive rigorous training in the performance of various types of ultrasound procedures. To become board-certified, they must pass an arduous certification exam. If there is a veterinary radiologist in your area, this is the best person to perform your pet’s ultrasound procedure. To locate a radiologist, you can go to the veterinary radiology website and search for a board-certified radiologist in your city or state.

If you can’t find a veterinary radiologist in your area, a veterinary internal medicine specialist is another good choice. Veterinary internists also receive ultrasound training during their residency programs, although their ultrasound training is not as extensive as that of a radiologist. Internists are also skilled at the interpretation of abdominal ultrasound results, since the abdominal organs are one of the areas in which they specialize. To find an internist in your area, you can check the internal medicine website .

An ultrasound exam of the heart (echocardiogram), for example for a pet with a heart murmur, should be performed by a board-certified veterinary cardiologist; you can find one in your area here.

One method to avoid for your pet is the “remote ultrasound”. In this situation, instead of having a specialist perform a full ultrasound exam, someone takes pictures using an ultrasound machine, and sends them to a radiologist for interpretation. Unfortunately many mistakes can occur with this method. If an abnormality is not recognized by the untrained person performing the exam, or the images are of poor quality, the radiologist cannot make an accurate assessment of the animal. This technique should be a last resort, for geographic areas where there is no radiologist or internist available.Owners should be given the choice of seeing a radiologist or internist and made aware that this option exists.

If you have never seen an ultrasound exam performed on a pet, here is a video of a puppy receiving an ultrasound exam to discover an object lodged in the intestines. As you can see, the procedure is not scary or uncomfortable for the puppy.

If your pet needs an ultrasound, or any other procedure, be an educated veterinary consumer. Read about the specialists that are available for pets; ask questions; get informed. Don’t ever be afraid to speak up. You and your pet both deserve the best that veterinary medicine has to offer.

10/09/2009

Boo! Keeping your pets safe from toxic treats

As Halloween approaches, and we all stock up on candy and other treats, don’t forget that some of this tasty stuff can be highly toxic to our animal companions. 

-Chocolate isn't safe for dogs, but they love it! Most of us have a lot of chocolate around the house as Halloween and the holidays approach - if you have a dog, remember to keep your chocolate in lockdown. Don’t leave it out on the kitchen counter, coffee table, or elsewhere around your home, since an enterprising dog will go to great lengths to snatch this delicious-smelling stuff. Baking chocolate is particularly dangerous, so never leave it out when you are busy whipping up tasty desserts.

-Xylitol. This sugar substitute, found in sugar-free candy, gum, baked goods and other desserts, as well as in a powdered form for baking, is extremely dangerous to dogs. A dog who ingests xylitol is at risk of dangerously low blood sugar, seizures, liver failure, and death. Check for xylitol in the ingredients of any gum or treats in your home, and keep anything containing this substance closed away in a high cabinet. Make sure to warn the kids too, since their canine friend may try to convince them to share. 

-Grapes and raisins. Because these can cause kidney failure in dogs, never give your companion grapes, raisins, or anything that contains them. This includes breads and cakes that contain raisins as well.

If you ever think that your dog may have eaten anything on this list, or another potentially toxic substance, immediately call an animal poison control line, such as the ASPCA’s Animal Poison Control Center. And don’t forget to keep your pets safely in the house around Halloween time, when the tendency for mischief-making might put your furry friends at risk.

10/05/2009

Pet Pain Patrol - Please Participate!

When choosing a veterinary practice for your pet, or deciding where to have a surgery or procedure performed, one of the most important parameters to evaluate is the practice's philosophy regarding pain control. In the olden days of veterinary medicine, many patients received little to no pain control after a surgery or injury. These days, many (but not all) veterinarians are vigilant about providing pain relief to the animals in their care. You need to ensure that the practice you use is up-to-date on both their pain control philosophy and the actual methods employed.

Failure to provide adequate pain control to animals is not only inhumane, it can also be severely detrimental to the animal's health and recovery. For example, pain has been shown to slow wound healing, increase rate of infection, cause shock and decreased circulation, and prolong hospital stays. 

Veterinarians must be proactive about recognizing pain in their patients. Pain is often underestimated in animals for a variety of reasons; for example, cats and older animals generally do not vocalize when in pain. It is essential to assume pain is present following a procedure or injury that would be likely to cause pain, and also to recognize more subtle signs of pain in veterinary patients. Cats are notorious for hiding significant pain. A cat in discomfort will often sit quietly in a hunched position, while a cat with proper pain control will have a more relaxed body position, move about, interact, and groom. If a dog or cat sleeps soundly with dreaming, this is a good sign of adequate pain control. Aggression is often a sign of pain in animals.

One very useful parameter veterinarians can use to evaluate for pain is the heart rate. An animal in pain may be lying quietly yet with an elevated heart rate. A good veterinary practice will assess the patient's heart rate at regular intervals, using a rapid rate as a clue that additional pain relief may be needed.

There are various medications available to provide pain control for pets. Some of the most commonly used options include narcotic medications, given as an injection, pill, liquid, or skin patch, and non-steroidal anti-inflammatory medications (NSAIDs), which may be supplied as an injection, pill, or liquid.

In some situations, NSAIDs should not be used due to the likelihood of significant side effects such as kidney failure and/or gastrointestinal ulceration. NSAIDs are contraindicated in animals with liver or kidney disease, gastrointestinal symptoms such as vomiting or diarrhea, and in patients who are dehydrated or having signs of shock, such as low blood pressure or low body temperature. Screening blood work to evaluate liver and kidney function is essential prior to administration of NSAIDs.

Use of NSAIDs in cats is controversial, with Metacam being a particularly well-known example. The manufacturer's instructions for oral Metacam state that this drug should not be used in cats, and indeed multiple reports exist of significant and even fatal consequences of oral Metacam use in cats. Regarding injectable Metacam, the manufacturer's instructions state that cats should only receive one injection of Metacam, and there are reports of even one injection leading to consequences such as kidney failure. Failure to follow the manufacturer's package insert directions is a risky business not only for the patient's welfare but legally as well.

One option for pain control in cats at home is buprenorphine (Buprenex), a liquid narcotic that can be given under the cat's tongue and will absorb from the oral mucosa. Because a very small volume is needed (around 0.1 cc in most cats) and because it does not need to be swallowed, it is easy to administer and this drug is nicely effective for many types of pain in cats.

Another relatively new development for pain control in both humans and animals is skin patches that release medication over several days. Skin patches containing the narcotic fentanyl can be used in both dogs and cats; care must be taken that the patch is not ingested by the animal. Below is a dog wearing a fentanyl patch.

Pain patch on dog small.jpeg 

And here is a close-up of the patch:

Fentanyl patch close up small.jpeg

As a pet owner, please be proactive in ensuring that your pet always receives safe and adequate pain control. Animals cannot tell us when they are suffering, or ask for help, so we must be vigilant in our efforts to protect them. Don't be afraid to ask about pain control for your pet, or to investigate the safety of any drug given to your companion.

10/01/2009

Take a look at safe anesthesia for pets!

As you can tell, my mission is to give pet owners the information they need to protect their pets' health and to wisely choose the best veterinary practice to help achieve that. I believe that knowledge is indeed power and have seen too many pets suffer because their owners did not have the tools they needed to advocate for their animal companions.

Today I suddenly realized (duh!) that just talking about ways you can protect your pet isn't enough; I need to show you. It's one thing to babble on and on about safe anesthesia and having your older pet's blood pressure checked and ensuring your pet receives safe and adequate pain control. It's another to let you see for yourself. If nothing else, picture are a lot less boring then listening to my nagging.

So, today let's talk about, and take a look at, what is required for safe anesthesia. Safe anesthesia requires monitoring equipment, so that when your pet's oxygen level or heart rate or blood pressure drops, someone knows about it and can do something to fix the problem before your pet actually stops breathing or her heart stops and...well, you know. Pets can die under anesthesia, and proper monitoring vastly reduces the chance of that.

At a minimum, your pet should be hooked up to a handy gadget called a pulse oximeter. This little gem monitors the animal's blood oxygen level and heart rate, good parameters to keep an eye on if you want to make sure someone keeps living.

Here's a picture of a kitty having his blood oxygen level and heart rate measured with a pulse oximeter. I think you'll agree he seems quite happy about it.

Pulse oximeter on cat 2 small.jpeg


You're right, he's not under anesthesia. You can also use a pulse oximeter in awake animals when you are concerned about their breathing, such as animals in heart failure or those with pneumonia. If the oxygen level is too low, the vet needs to do something about it rather quickly, such as place the animal in an oxygen cage.

Another component of safe anesthesia is called intubation. This means placing a tube in the animal's trachea (windpipe) to deliver oxygen and anesthetic gas. If an animal under anesthesia is not intubated (if the anesthesia is delivered with a mask, or just by injection), there's not much anyone can do if that animal start to crash or stops breathing. But if the animal is intubated, the vets or technicians can ventilate the animal (breathe for her).For example, if the pulse oximeter shows the animal's oxygen level is dropping, the folks doing the anesthesia can give the animal a few oxygen-rich breaths by sqeezing on the oxygen bag a few times. Or, as I mentioned above, if the animal stops breathing completely, they can use the tube to breath for the animal. Can't do that with a mask and certainly not for an animal who just got an injection. Then it's rush rush rush to try to get a tube in before the pet dies. Not good.

Here's a kitty who is under anesthesia and intubated.

Intubated cat small.jpeg


See that little black bag on the lower left? If the kitty's oxygen level drops or she stops breathing, the vets or techs can breathe for her by squeezing the bag.That way they can keep her cute little tongue nice and pink like it is in the picture.

The other thing I want you to notice about the cat above is that she has in IV catheter in her leg. This is also super important for safe anesthesia. If this little cat's heart slows down, she can be given a drug to speed it back up through the catheter. If her heart stops, she can be given epinephrine to help re-start it. If her blood pressure drops, she can be given a bolus of IV fluids or medications to correct this.

OK, gotta run to work now. Now you know all about safe anesthesia; don't let your pets receive anything less!

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