I'm On The Move!

Posted by Aaron

Tuesday, February 23, 2010

There's lots of big news here in Texas. I found out last week that I have been accepted into an Internal Medicine Residency at Oklahoma State University in Stillwater, OK. I will be studying for my PhD and obtaining board certification at the same time.

By the end, I will be a boarded "specialist" in internal medicine and have the PhD. This will allow me to stay in academia and teach. My hope is to be involved in research focusing on diabetes and the hormones that fat tissue produces (called adipokines).

This is HUGE EXCITING news! We will be moving this summer and I start the new job on July 1st. I'm not sure I will be able to continue the blog. I have to see what latitude I will have while in the program. I also expect to be CRAZY busy for the next 4-6 years.

I do so love my wife! This could only happen with the support and love of my family and my wife is going above and beyond! I'm both blessed and spoiled. My daughters are excited to be going on an "adventure" and are looking forward to picking out their new house. We'll see how excited they are when it's time to actually move....

Thanks to everyone for their support and I promise to keep posting until at least July. We'll see what happens after that :)


Pearl Pee

Posted by Aaron

Dr. Herndon,
I have a question for you regarding urinary issues. I have a 4 year old pug, Pearl, with chronic urinary issues.
History-wise, our first issue was about 8 months ago when she suddenly could not urinate one morning. We rushed her to the vet, where they surgically removed a blockage caused by struvite stones. She had shown no signs of discomfort and we had no idea she had any stones up until that day. He placed us on Hill's W/D because she needed to lose a few pounds and thought it would also help regulate her urinary issues.

A few months later, we began to see blood in her urine, and dripping out after she urinated. We went back to the vet and started Primor which, we thought, cleared up the infection. We continued to feed her the W/D and I started her on an all-natural cranberry supplement.

Last weekend, the bloody urine started again. We are back at the vet today and doing another round of antibiotics. The pH of her urine today was 8. This surprised me, as I hoped that the cranberry supplement would help acidify it. Although, if my understanding of this all is correct, the infection can cause the urine to become more alkaline- regardless of what I am supplementing her with. It seems like this pattern continues, and I am not sure where to go from here.

She always has a clean water source available to her, we get her outside very often to use the bathroom, and I am just feeling exhausted with this process. I want her to feel better, and it seems like this current diet is just not helping.

I have been uncomfortable with the Hill's diet this entire time, because the ingredients just do not seem wholesome to me. I am not necessarily insistent that she be on a grain-free diet or anything, but surely there is a more nutritious food that could work similarly. I am willing to make her food at home, if that would help.

Can you offer me any advice on food/supplementing, and any other general advice for her urinary health? She is otherwise very healthy and we are so eager to rid her of these infections.

Thanks so much for any help you can offer!

-Pearl & family in Oklahoma

Isn't it amazing what they will put up with and never complain?

Everything you have said is pretty much spot on.

Urine is what is produced when the kidneys have filtered the blood and then that filtrate is concentrated, diluted, concentrated again and various electrolytes, etc are put into and taken back out of the urine. Eventually that product is dumped down-stream in the urinary bladder. All of this amazing concentration and dilution is how the kidneys regulate things like sodium, potassium, pH, and overall hydration.

ANYWAY - There are all kinds of compounds in the urine that can precipitate out in the form of crystals. This is like what happens when you make a concentrated sugar-water solution and the sugar makes those cool crystals. Crystals form when a solution is saturated enough. pH of the urine also plays a huge role. In an acid urine, the phosphate and magnesium compounds that make a struvite stone can't form. Other stones can form in any pH urine (like calcium oxalate stones), but prefer acidic urine. It's not an entirely accurate equation but acid makes oxalate, alkaline makes struvite.

Different types of bacteria can have different effects on urine pH. Some are known to produce alkaline urine and are also capable of producing the enzyme urease that causes the struvites to form.

In nearly 99% of CANINE stuvite cases, urinary tract infection is directly to blame. Treat the infection, treat the crystals. There are those fairly rare cases where the pet is able to make struvites without infection. Keyword - RARE. Oxalate stones can "just happen" and are typically much more diet related. Bichon dogs are terribly prone to oxalate stones.

There are different approaches to dietary management of these guys. Since crystals can't form if the urine is dilute, it is important to try and address that first. Increased water intake is important. This may mean canned diet. Therapeutic diets can also be used. Now this is ENTIRELY OPINION, but I don't like Hills. Never have, never will. They have some great diets (of which w/d is one of them), but Hills and I don't get along and I don't like their attitude and approach to certain disease conditions. I'm a Royal Canin man. They aren't perfect, but I sure do like them worlds better. The goal of w/d is NEUTRALITY. It's low(er) calorie, low(er) phosphate, high(er) fiber. It is a great middle-of-the-road diet for someone like Pearl. However, it does nothing to prevent crystals and nothing to dilute the urine. Royal Canin's approach is to dilute the urine first and foremost (which I think is by far the most sane approach). Hill's other diet, c/d, is designed to acidify the urine. Doesn't dilute it. It's also higher in fat. So now I have a fat dog with acidic, soupy, concentrated urine and I haven't really gained any benefit. Can you tell how I feel about c/d?

RE: naturapathic/"wholesome" food choices. I'm a fan. I think that, in general, there is something to be said about taking a more whole-food approach to diet. I like limiting the grain content (although I'm not a grain-free advocate). Cranberry is effective, but it doesn't do much to acidify. Cranberry gets its credit because the tannins in the cranberry prevent the bacteria from adhering to the bladder wall so well. If the bacteria can't adhere, they get peed out and that's not healthy for a bacteria. HOWEVER, there are no manufacturers who are trying to develop therapeutic diets that are ALSO organic, whole-food, naturapathic. When someone does, I'll probably be right there with them. If we have a specific dietary need and a disease condition to treat - we have to resign ourselves to the more traditional diet choices. These diets are fantastic, to be sure. The argument against the "traditional nutrient" approach is more philosophical than factual at this point in our understanding about canine nutrition.

So - Pearl's case is complicated by her weight and her lack of being honest with her symptoms. Her "well-loved" stature means we have to be VERY careful of her weight. Hills c/d and Royal Canin s/o are both higher in fat. W/d is a valid choice for her. Royal Canin Calorie Contral HP is also a valid choice, and would be my first choice. It will be better for weight loss and will still have similar "stuvite preventative" effects as w/d. We must STILL INCREASE HER WATER INTAKE.

We are also going to have to be pro-active with her monitoring. This means we have to continue to get repeat urine samples after the treatment is successful and monitor her for recurrence. We're going to have to go looking for the infection and not wait for it to come to us. This may mean once monthly urinalysis at a minimum.

Why does she have so many urinary tract infections? Well, there's the BIG question since we know the stones are just a secondary player. The way I answer this question (which I get frequently) is to tell you what PREVENTS a bladder infection. Any breakdown in these preventative measures will set up the possibility of infection:
  • Urethral length - it's easier for a female to develop infection than a male (in most species - cats are an exception) because the urethra is much longer in the male.
  • Normal and complete emptying of the urinary bladder. Simply put - you don't pee often enough, you set yourself up for infection.
  • Insufficient water intake. Soupy, concentrated urine ain't helpful.
  • Normal immunity along the lining of the urethra. This is a combination of antibodies the body produces (Specifically, IgA), the mucous layer of the urethra and bladder (made up of PSGAGs, glucosamine, and other large starch and protein molecules), and the anatomy of the vulva, vagina, urethra, and urinary bladder. There are all kinds of plumbing issues that can pre-dispose to urinary tract infections. If the vulva is "tucked" up high and urine pools in the vestibule or vagina, then you are pre-disposed to issues. If you're male - having testicles pre-disposes you to problems because of that annoying prostate. Intact male dogs are at higher risk than neutered male dogs (generally speaking).
Who knows which is exactly Pearl's issue. Could be a combination of all of them. Additionally, we have the question of whether the bacteria involved are being effectively killed during a course of treatment. She may have a smoldering UTI and so culture of the urine before and after treatment may be a VERY smart thing to consider. Once we culture the bug the lab will help us determine what antibiotics are most likely to work and we can make sure we're using the right one.

So my initial recommendation to you is to finish this round of antibiotics (probably 21 days worth of antibiotic) and keep rechecking the urine. I'd consider culturing the urine when she's been done with the antibiotic for at least 5 days. Your veterinarian will get the sample directly from her urinary bladder (it sounds dramatic, but it isn't). We must make absolutely certain that the infection is gone. Start her on a joint supplement. These are only going to help the bladder. Vitamin-C containing products are nice. Dasuquin and Synovi-G3 are both good products worth considering. If we are still having problems with re-infection, then ultrasound of the bladder to look for things like a polyp or pocketing of the bladder wall is a very smart move. Be patient - we can usually get to the bottom of this and then focus on prevention alone. I'm suspicious we may not be completely and totally resolving the infection or there's a polyp or some similar problem allowing the infection to keep hiding out.



Posted by Aaron

Sunday, February 14, 2010

I received this question in the mail the other day:

Dr. Herndon I own two pugs and one is a rescue I have had for two years. She has tracheal collaspe and is roughly 10 to 12yrs old. She has other health issues such as PK of the eyes, arthritis, fx vertebrae with disc herniation and mildly enlargerd heart. I was wondering what treatments would be considered to help decrease the consistent coughing and ease her breathing so she isn't working so hard just to take a simple breath. And what other insights do you have on this condition in dogs.

The first thing I have to say about Miss Petunia is WOW! Sounds like she has more than her fair share of stuff to deal with!

Let's take these issues one at a time, shall we.
1)Tracheal collapse: This is a condition where the trachea forms in a more flattened shape instead of a more circular/rigid form. As a result, the top of the trachea (which under normal circumstances is a thin band of flexible tissue) is much wider and "floppier" than usual. When you breathe in, physics says that the air pressure decreases and that floppy ceiling waggles in the breeze. At times it can actually flop all the way down and "snap" the trachea shut for as split second. Collapsing trachea will worsen with age as that floppy ceiling gets stretched and inflamed over time. These guys usually cough quite a bit - ESPECIALLY when they are excited or exercising (your breathing rate and speed increases and that makes the collapse worse).

2) Pigmentary Keratitis (PK): This means that the cornea gets covered in pigment. Instead of a clear front to the eye, you instead end up with a dark, sometimes black, covering to the cornea. These guys are functionally blind. It's like wearing black sunglasses.

3) Fractured verterbra and herniated disk: This means that one of the backbones has a break and the disk between the two is bulging up into the spinal canal. This probably means that she is 1) in chronic pain and 2) probably has some difficulty moving her back legs in concert with the rest of her body. Neither of those have to be true, but they probably are.

4) Arthritis: This is a general term describing wear and tear on the joints. "Degenerative Joint Disease" is another term. We all get some degree of arthritis in our joints at some point.

5) Mildly enlarged heart: Exactly that. There is probably some degree of heart disease and that has caused the heart to change shape a bit and "stretch out." There probably isn't any overt failure, but the heart is showing some changes. Fairly common in older individuals. As it enlarges, the heart will push a bit on the airway where the trachea splits. This can cause cough as the heart beats and tickles the trachea and bronchi. Cough due to this is usually worse when the patient is lying down, ESPECIALLY when lying on the back.

See what I mean? She's got lots of issues! So now what?

PK - steroid drops in the eyes can help slow it down, but once advanced, there's not much to do.

Arthritis - Use a combination of therapies. Glucosamine, Adequan, pain medications (NSAIDS, narcotics), acupuncture and/or chiropractics.

Heart - if no evidence of failure, my opinion is that we do nothing. There are arguments on whether certain medications can slow progression of disease. Unless there is overt failure, there isn't any need. HOWEVER, omega-3 fatty acids (fish oil) have been shown to do all kinds of wonderful things for the body including slowing progression of valvular heart disease. Best thing is that fish oil ain't gonna hurt a thing.

And now we're back to the collapsing trachea. Narcotics are a great choice to stop the kind of irritation and automatic cough produced by a collapsing trachea. Tramadol is narcotic-like and has the benefit of being cheap and easy to get. Tramadol would provide multiple kinds of help for her! It would provide pain management for her back and would have the added "side effect" of helping the cough. By far and away my favorite cough medication for dogs is hydrocodone/homatropine (Tussigon, Hycodan). The stuff usually works miracles on collapsing trachea. But it is controlled (meaning the DEA keeps track of it and there is more paperwork involved), more expensive, and at times has gone on backorder and been impossible to find. Tramadol is a great substitute but doesn't always work quite as well.

Narcotics are used several times daily - sometimes as frequently as every 4 hours, but we try to use them when necessary and no more than twice or three times daily. What we are trying to do with cough medications is keep obnoxious coughing fits under control. Not eliminate the cough all together.

Steroids (like low dose prednisone or a combination drug like Temaril-P) may help and may be necessary from time to time. HOWEVER, you CAN NOT use steroids at the same time you are using a NSAID (like carprofen) for the arthritis. So you and your doctor will have to decide which is more important and pursue that course. Steroids aren't something we should use long-term either, so again, you have to weigh the risks and benefits with your veterinarian.

In Petunia's case, it sounds like Temaril-P and Tramadol may be a good combination when things are bad. Tramadol alone may be enough. The thing with these guys is that there is no one answer. We have several different arrows in the quiver and we just have to see which one comes closest to the bulls-eye.

We also need to limit her "excitement." We don't want to go on long walks, don't want to chase the ball. Use her symptoms as a gauge of your exercise limits. When her symptoms worsen, you have to back off the activity. Obesity and pugs often go hand-in-hand, so some activity is a good idea, but we don't want to force her over the edge.

One note on PREVENTION of pug respiratory problems. Pugs are prone to having excessively narrow nostrils and long soft palates. If you have a young pug (or puppy) and they snore and snort too much - talk to your veterinarian about having the nostrils fixed or the soft palate trimmed. Opening up the airway takes a LOT of pressure off the trachea and palate and can DRAMATICALLY improve symptoms. Constant pulling against narrow nostrils can stretch out the soft tissues and make everything WORSE!! Now they tire quickly, have trouble breathing, can't exercise, get fat, have even more trouble exercising and it's damn near impossible to fix it after everything is collapsing! If your veterinarian says the nostrils are too narrow - it's worth EVERY PENNY to have them worked on. I'll post more on that later.


The Results are In - 2nd post

Posted by Aaron

Saturday, February 13, 2010

There are LOTS of things that can be measured using serum or plasma. What I want to focus on here are the typical things we look for on a "general chemistry" or "blood chem" or "chem 6, 12, 27" or whatever.

Serum or plasma is the golden to clear liquid that is left on top after you spin all of the cells down and out of the blood. (Serum has the clotting factors and such spun out, Plasma is blood with everything BUT the cells)

Most of the things we are testing for are either waste products, electrolytes, or enzymes. The enzymes we measure are leaked out of tissues (like liver cells or pancreas) and there is always a little bit of "normal" leakage going on.

Let's break them down into groups:
  • BUN or Blood Urea Nitrogen. BUN is made by the liver from the ammonia produced when the body burns proteins. BUN is then eliminated from the body by and large from the kidneys. It is a very labile compound and can rise and fall quickly. Usually an increased BUN is associated with kidney dysfunction
  • Cr or Creatinine. Cr is a waste product from muscle (mostly). It is also excreted by the kidneys. Cr is much less labile than BUN and tends to rise slowly. It is also a good indicator of renal disease. I think of Cr as the "chronic" indicator and BUN as the "acute" indicator.
  • All of the electrolytes are tightly regulated by the body. It's really amazing! The gut will dump electrolytes like chloride when needed. The kidneys dump sodium and potassium if needed. There are complex mechanisms by which the kidneys trade sodium, chloride, potassium, and bicarbonate and all of this is influenced by certain hormones like aldosterone and cortisol. The pH of the blood is regulated by a whole host of processes. Electrolyte regulation and pH regulation rely on each other. Additionally, the lungs (respiratory rate and function) build up or blow-off carbon dioxide. The carbon dioxide turns into bicarbonate in the blood and the pH raises and lowers accordingly. It is a fascinating process and I've just summed up entire textbooks in this paragraph.
  • No one electrolyte can be looked at by itself. When evaluating these, we have to look at all of them together and ratios between them all.
  • Sodium is one of the three "main" electrolytes we measure. It is very labile and can change quickly. Sodium tends to increase with dehydration. It is somewhat influenced by diet, but the body dumps extra sodium in the urine if extra sodium is in the food.
  • Chloride is an electrolyte that doesn't get much respect. Probably because it tends to follow sodium around. Chloride can change fairly dramatically in cases of vomiting and diarrhea, but I have trouble getting too excited about chloride.
  • Potassium is probably the one electrolyte that people pay the most attention to. It can reach dangerously high or low levels in many different disease processes and it is the one electrolyte that we are usually trying hardest to address. When the blood is more acid (like in a sick diabetic) the potassium is dangerously low. Vomiting also produces low potassium. Potassium is high when we can't urinate (as in cases of blocked tom cats). High potassium causes the heart to slow way down and stop. There is 35 times more potassium IN your cells than OUT of your cells. When total body potassium is low, it can take quite a while to get it back up.
  • Magnesium - not measured often enough. Can be way off with GI disease. Not usually supplemented much, although when it is low, these patients feel MUCH better when magnesium is corrected.
  • Phosphorous/Calcium - these two are like yin and yang to each other. Phosphorous will increase dramatically in cases of kidney failure. Calcium can go up and down with albumin (since albumin carries this electrolyte). Low blood calcium that happens immediately after giving birth is called eclampsia or milk fever.
  • Most liver enzymes we check are enzymes made by the liver and contained within the liver cells. The idea is that damage to the liver or stress to the liver cells will cause them to "leak" more enzyme causing blood levels to increase.
  • ALT (alanine amino transferase) - This one is the most specific to liver "damage" or "disease." ALT goes up when the liver cells are killed or squished (hit by car animals have high ALT because the liver was squished).
  • ALKP (alk phos, alkaline phosphatase) - This enzyme is not exclusive to the liver. It's also made in bone and white blood cells, so increases in this level must be looked at in perspective. It is much more important in the cat. Increases in the cat are almost always associated with liver upset.
  • Albumin - the blood protein found in the largest quantity in the blood. It is made by the liver and chronic liver dysfunction can cause albumin to go down.
  • Bilirubin - bilirubin is the by-product of the body processing hemoglobin out of the body. This happens normally on a daily basis as the body takes out old, dead red blood cells. It is largely excreted from the body in the bile. Buildup of this compound (which is yellow-orange) causes jaundice or icterus. Increased bili can mean the outflow of bile from the liver is bummed up or it can mean the liver's ability to deal with all of it is overwhelmed (like if the red cells are being damaged too fast).
  • GGT (Glutamine amino transferase) - Another enzyme. Very valuable to know in the cat as GGT and ALKP are usually increased together and can help you get a more accurate picture of feline liver function.
  • Ammonia - Not routinely done. Ammonia is taken out of circulation and turned into BUN. If blood is shunted around the liver instead of THROUGH the liver (like it's supposed to be) the ammonia levels rise.
  • Bile Acids - These are the things that the liver makes and are excreted in the bile. basically they are required to digest and assimilate fats and cholesterol. Sometimes they are used to measure liver dysfunction by measuring them on a fasted sample and one after feeding.
The Other Stuff
  • Blood Proteins - Albumin (mentioned above) is made by the liver. It carries all kinds of wonderful things around the body (hormones, drugs, calcium) and when it is low we have to take it seriously. The most common reason for a low albumin is that it is being lost - blood loss or protein loss through the kidneys, gut, or skin (like in burn patients who loose BOAT LOADS of albumin in a hurry). The other population of proteins we look at are the globulins (antibodies). Globulins increase when the immune system is responding to something. Raging high globulins in a cat with fever and fluid in the belly is one hallmark for FIP, for instance.
  • Glucose - blood glucose (blood sugar) is quite labile and is tightly controlled by the pancreas (insluin). During periods of stress, the blood sugar increases slightly due to stress hormones like cortisol being produced. Really high levels of blood glucose typically mean diabetes. Really low levels can happen in severe infection, liver failure, small breed puppies (puppy hypoglycemia or small breed dogs), or if there is a tumor in the pancreas secreting EXTRA insulin of if a diabetic is given TOO MUCH insulin.
I'm sure I've forgotten some and the list is already really long. If there is a particular blood chemistry that I've missed and you want to know about, just ask.


Comment setting updated

Posted by Aaron

Sorry folks, but I had to change the setting for comments to ONLY allow registered users. If you want to leave something anonymous you'll have to register a fictitious user. I kept getting spammed with comments selling peter-pills, drugs, and asking for money. Although I have nothing against peter pills, the whole getting spammed with crap was getting on my nerves. So I booted it.

Keep the comments coming, though!


Cat Aerobics

Posted by Aaron

Wednesday, February 10, 2010

I promised a post on cats and how to encourage exercise. I'll post a few ideas, but I would LOVE to hear some ideas you guys have for encouraging cats to be active. It's not always easy!

  1. Get another cat. This can backfire BIG TIME! Cats are, by their nature, fairly solitary. Some cats are social and like to play. Other cats are enormously stressed by another cat and they will instead hide. This totally depends on your cat and your situation. I know in my house the cats play a lot and having more than one is a good thing for their activity level. Once you adopt a cat, it is your family member to love and support for life. Do your homework and make sure it's a good fit. Most rescue organizations will allow extended home visits (over a period of days) to see just how well everyone gets along. Don't rush into this.
  2. Get some outside time. Outdoor cats are at greater risk for quite a few things. Trauma, disease, and fights to name a few. That doesn't mean that you can't give your cat outside time. Look at this website - www.catfencein.com. We've installed it at our house and now my cats have free access inside and out, but they can't get out of the yard. I'm amazed at how much the sunshine and playing in the grass improves their attitude. I've always been reluctant to consider having a cat with unfettered access to the outdoors, but this works great for me. In Connecticut, I built a huge hutch that the cats could go play in. We had to carry them out to it, but then they could play in the giant cage all they wanted.
  3. Toys - cats are funny about toys. Perhaps cats just are too important to tell us what they want to play with, or they consider it beneath their status to actually play when we ask them to. They would much rather play at night by running across our bed at warp-speed scaring the bejeesus out of us and causing us to jump up from a deep sleep while screaming out language that would make a longshoreman blush. My best results have been with milk-jug tops, feathers, empty PAPER bags, and cardboard boxes. Feathers on a string are tons of fun, but require owner participation. I've seen motorized mice that looked like tons of fun.
  4. Laser pointer/flashlight. You can get really cheap laser pointers and some cats love to chase the pointer. Don't shine it in their eyes - sounds like it should go without saying, but remember that your cats eyes are just as prone to damage from the laser light as you are.
  5. Catnip. Legal in all 50 states. Purchase a baggie for a steal compared to other weeds of similar appearance. The active ingredient is nepatalactone and its mode of action in the brain is poorly understood. Most cats experience a high and will have a sudden increase in appetite. Some drool. Some get angry. Some simply don't experience anything. I call them Nip-positive and Nip-negative. Grow your own - it's also legal in all 50 states to have as many nip plants as you like. You don't have to build any expensive, hidden greenhouses in your garage or dorm room closet. Cheap, very prolific plant. It's in the mint family and WILL GROW OUT OF CONTROL if you don't limit it by potting up the plant or providing space for it to spread.
How much exercise? I've heard 20min/day is a great start. If I am trying to encourage weight loss, that's my goal. To help improve the cats attitude and break bad behavior, ANYTHING will help.

Leave a comment with your ideas on how to get your cat to be active! This should be a community/interactive post!


Flatulence - aka "Honey, What's that SMELL!" part deux

Posted by Aaron

Sunday, February 7, 2010


Children and grown men around the world find it endlessly amusing.

Basically flatulence is the passage of gas from the anus. That gas can be something swallowed or something made by the individual. If you swallow enough air, some of that will make its way through the gut. It will pick up certain odors along the way and ultimately pass through the tail pipe.

The bacteria in the gut (especially in the colon) can ferment all kinds of energy sources and can produce plenty of gas as a by-product. The worst smelling of these can be the sulfur compounds. Sulfur has the classic "rotten egg" smell. In fact, eating lots of eggs can be an excellent way to have some seriously foul gas. The cruciferous veggies are pretty bad about it too.

So how do you manage it? Watch what you eat. Your body will tell you when something isn't being digested properly. Certain foods will cause guaranteed problems in some individuals. You can also take a pro-biotic. There are lots of yogurts out there that help get your digestive system on-track. There are also oral supplements intended to accomplish the same thing.

In the case of your dog - the same applies. Some dog foods will cause problems in some dogs. For example - my dog Kate. I really wanted to feed Kate a particular food that I thought I would like. The ingredients were the kind I liked, the formula was a good one for her. BUT, within 24hrs of feeding it to her it because immediately apparent that the side effects were not worth it. She had solid stools and felt fine, but the gas was peeling the paint off the walls and waking us out of a sound sleep. So that food was not for her. Switch her back - gas goes away.

And there are some breeds that are worse than others. I am going to pick on Boxers and Bostons (lesser degree Bulldogs and Labs). If you own a boxer dog or a boston, you must simply accept the fact that you will be constantly serenaded by your dog playing the booty trumpet.

Yes, you can give your dog plain yogurt. That can help. You can also experiment with foods by gradually changing to a different diet (look for a diet with different primary protein and carbohydrate sources). Or you can just deal with it and laugh when your dog goes up under the dinner table and cuts loose with something perfectly horrid during Thanksgiving Dinner. Just blame it on old Aunt Alice.


The Results are In - 1st Post

Posted by Aaron

Friday, February 5, 2010

I've had trouble thinking of good ideas to blog about. So I've decided to spend a couple of posts talking about "lab results."

How many times have you heard, "We're going to run some tests," or, "the blood work all came back normal." WHAT DOES THAT MEAN?

Let's break it down and over the next few posts talk about some of the common tests that are run and what kind of information we can get. I will discuss the complete blood count, basic blood chemistries (including electrolytes), endocrine chemistries, urinalysis, stool analysis (see previous blog on this one), biopsy (histopathology) and cytology, and bacterial or fungal cultures.

For the first installment, I thought we would start with the Complete Blood Count (CBC). It is the most straight forward to discuss.

A complete blood count is just what it sounds like. We are trying to measure all of the types of blood cells and provide information about their age, distribution, and health. There are three main numbers we look at. Total white cell count, total red cell count, and platelets.

White cells got their name because when you get a bunch of them together, they look white (or kind of white - think pus which is a few billion white cells all together). There are 5 types of white cells we generally measure and the total white count (WBC) is simply all of these types added up.
  • Neutrophils - these are the fast attackers. They are shortest lived of the white cells. They are the "first responders" to inflammation or infection and it's the neutrophils that are sacrificed in huge numbers (again, think pus). Typically, the neutrophils are the most numerous of the white cells - typically 60-70% of the total count. If the neutrophils appear young or have "toxic" changes, it helps tell us more about the type of response the body is mounting. Young, toxic neutrophils are usually in response to severe, systemic bacterial infections.
  • Lymphocytes - The smaller, rounder white cell. They make up the second largest population. usually 20-40%. There are multiple "flavors" of lymphocytes. T-cells, B-cells, plasma cells. Basically all of the same family tree. Lymphocytes are responsible for various roles in managing the immune system. They don't eat stuff, they tell other cells to go work, go eat, or to make certain chemicals. They take control by using cellular contact chemicals (known as cytokines). For instance, Killer T-cells will tag a cancer cell and trigger it to die. The T-cell then tells the macrophages to eat the dying cell. B-cells are largely responsible for making antibodies.
  • Monocytes - These are the biggest white cell and are responsible for much of the clean-up work. They can eat all kinds of stuff. If it needs to be cleaned up or eaten, monocytes are usually involved. They are usually about 5% of the total population. When monocytes leave the blood stream and enter a tissue that are re-named a macrophage. There are some highly specialized macrophages located in certain places in the body (like in the liver) that play a major role in regulating the immune system (kind of like the lymphocytes).
  • Eosinophils - Similar to a neutrophil. These guys have large, reddish granules in their cytoplasm. Usually 1% or so of the total. Eosinophils have similar roles to the neutrophils, but they are primarily "turned on" when parasites are involved or in the case of allergic reactions/chronic allergies. Cats have a very interesting ability to mobilize eosinophils and the eosinophils can cause all kinds of problems when you get too many together all at once.
  • Basophils - Very few are seen in the blood. It's actually kind of exciting to find one because they are typically fairly hard to find. They are in many ways just like an eosinophil.
If white cells are increased, we look at which ones. Neutrophils usually increase with infection of some kind (but any kind of stimulation to the immune system can cause increased numbers). Too few indicate life-threatening infection or that the bone marrow has been hit (as with parvovirus or chemotherapy). Increased monocytes can be seen in fungal infections or in cancer. increased eosinophils are usually associated with parasitic or allergic causes.

There are even some blood "parasites" that can be seen inside the white cells. Ehrlichia is one such infection.

Red blood cell counts:

The most common way to describe how many red blood cells an individual has is to use the packed cell volume (PCV) or hematocrit (HCT). PCV and HCT are basically percentages. If you take whole blood and spin it down (pack it) then you can compare the volume of red cells to the total volume of blood. Most blood is around 40-50% cells and the rest is all plasma.

Too few red cells = anemia.
PCV 30-40% - mild anemia
PCV 20-30% - significant anemia. Probably seeing "tired" pet.
PCV 15-20% - severe anemia. Something needs to be done.
PCV 10-15% - life threatening anemia. Something HAS to be done
PCV less than 10% - incompatible with organ function. Rapidly fatal.

Red blood cells are first and foremost an oxygen delivery system. Too few means not enough oxygen getting to tissues. Too many (pretty rare) and the blood is too thick and can't flow.

Baby red blood cells are darker and larger. Really immature red cells still have a nucleus (something that the adult cells have lost). Baby cells aren't very good at transport of oxygen. They're not the right shape yet and don't have all of the hemoglobin they will have as an adult. If you see baby reds in any significant number, you know the bone marrow has been told to make more. Usually this means the body is responding to an anemia.

Platelets - these are actually little cell fragments of a cell called a megakaryocyte (found in the bone marrow). Platelets are responsible for making a clot. You are always leaking. Always. Platelets go around plugging up that leak. Without them, you bleed to death. Honestly. There are usually 200 thousand or so in each milliliter of whole blood.

I could continue discussing all of the interesting things about blood cells, but I've gone on long enough. At least you have an idea of what they are looking at when a CBC is done. Complete discussions on interpretation are entire books in and of their own.

Next post - The basic blood chemistry.