Some Fun Quotes

With the holidays, I thought I would do a little lighter topic.  Here are some fun pet related quotes:

“Don’t accept your dog’s admiration as conclusive evidence that you are wonderful.”-Ann Landers

“Did you ever walk into a room and forget why you walked in? I think that’s how dogs spend their lives.”

-Sue Murphy

"Dogs are not our whole life, but they make our lives whole." -Roger Caras

"A cat is a puzzle for which there is no solution." -Hazel Nicholson

"Animals are such agreeable friends - they ask no questions, they pass no criticisms." -George Elliot

“Dogs are the leaders of the planet. If you see two life forms, one of them's making a poop, the other one's carrying it for him, who would you assume is in charge.” -Jerry Seinfeld

"I like pigs. Dogs look up to us. Cats look down on us. Pigs treat us as equals." -Sir Winston Churchill

Hope everyone has a happy holiday.

Silly dog, You ate what???

Now that I have discussed hazards among cats, lets talk about problems that dogs may encounter.

1.) Tinsel, ribbons, and ornaments:  Although these decorations are not toxic, they can definitely cause problems with your pets.  In particular, longer, thin decorations can cause major problems as they tend to turn into linear foreign bodies.  Unlike a ball, corn cob, etc that may be eaten and removed fairly easily, longer string like objects tend to get hooked higher up in the stomach and intestine and then continue to move down the intestinal tract.  This leads to a large amount of damage that tends to make it more difficult to remove and heal from.

2.) Holiday lights and candles: The constant flickering of lights or bright colors can be very attractive to pets.  The problem with this is the electricity running through the lights.  You may not get the reaction like in "National Lampoon's Christmas Vacation," but biting into a cord can cause significant mouth burns and possibly death.  Make sure lights are out of the way of your pet.

3.) Holiday food: With the holidays comes baking and cooking, so be cognizant of what you leave out.  Chocolate is a big concern in dogs.  Although all chocolate is bad, baking chocolate contains the most methylxanthines, which can cause heart arrhythmia and death in large enough doses.  Other fatty foods and trimmings can also cause issues.  High fat foods can trigger pancreatitis in your pet leading to vomiting, pain, dehydration, and in severe cases, death.

4.) Antifreeze: Although not really a holiday problem, antifreeze becomes more readily available during colder months.  In the past antifreeze has been enticing to pets due to its sweet taste.  Fortunately, legislation passed last year that requires manufacturers of antifreeze to add a bittering agent to the liquid that will make it less tempting to pets.  Pets only need to be exposed to a small amount of the liquid to cause a problem.  Pets typically succumb to renal failure if they are not treating early and aggressively.

5.) Holiday plants: The good news is that most plants will only produce mild gastrointestinal upset if your pet is exposed to them.  Poinsettias, holly, and mistletoe typically fall under this category, but with large exposures there can be other problems, so always contact your veterinarian.

The best way to avoid a problem with your pet this holiday season is to keep anything that could be a hazard out of their reach.  Have a safe and happy holiday season.

Holiday Hazards

With the holidays quickly approaching I wanted to take time to discuss some holiday hazards to try to avoid.  The first post will deal mostly with cats and is taken from Dr. Tina Wismer's handout from a talk she gave for a rounds discussion in 2010.  Listed below are some common items that a cat might encounter during the holidays along with descriptions of possible problems.

1.) Silica Gel Packs

Desiccant packs are included as moisture absorbents. They are found in shoeboxes, electronics, medications and food. Silica gel comes in paper packets or plastic cylinders. Packages of silica gel are attractive to pets because of the rustling noise, and the packages are easy to bat around. Most ingestions will not cause clinical signs, although a mild gastrointestinal upset may occur. If a large amount is ingested, there is potential for diarrhea occurring. In most cases, the packet will be ruptured and the contents eaten. Ingestion of the intact packet may cause an intestinal obstruction.

2.) Christmas tree preservative

Christmas tree preservatives primarily contain dextrose and NPK fertilizers. The concentration of metals (copper, iron, zinc, magnesium) is usually small in commercial products. Most cats that drink water containing Christmas tree preservative develop no signs. Occasionally we can see mild GI signs, rarely, bacterial/fungal contamination of the water may lead to more severe signs.

3.) Christmas trees

Christmas trees may be one of several species. The most common are: Douglas fir (Pseudotsuga menziesii), Balsam fir (Abies balsamea), Black spruce (Picea mariana), Blue spruce (Picea pungens), White spruce (Picea glauca), Scotch pine (Pinus sylvestris), Norway spruce (Picea excelsa), Red Pine (Pinus resinosa), and Red spruce (Picea rubens). The most common clinical signs after ingestion of the needles are vomiting, anorexia, abdominal pain and depression.

4.) Poinsettias

The toxicity of poinsettias is generally overrated. The plants do contain diterpene esters, but large quantities must be ingested for signs to develop. Most cats just experience mild, self-limiting vomiting that resolves with little to no treatment.

5.) Mistletoe

Most ingestions involve American mistletoe (Phoradendron spp.). Mistletoe contains lectins, but ingestion of a few leaves or berries will generally cause just a mild gastritis. If purchased in a store, the berries frequently have been removed and replaced with plastic "berries" which can be a foreign body. Large ingestions may require decontamination and cardiovascular monitoring.

6.) American Holly

American holly (Ilex opaca)is a member of the Aquifoliaceae family. All parts of the holly plant are considered to contain potentially toxic compounds, including methylxanthines, saponins, and ilicin. True toxicoses not generally expected in cats. Most ingestions cause gastrointestinal irritation and depression. Recent ingestions can usually be managed with dilution and monitoring at home.

7.) Lily

Members of the Lilium and Hemerocallis genera (Easter lilies, tiger lilies, day lilies, etc.) cause acute kidney failure in cats. The water soluble toxic principle is unknown. Even minor exposures (bite on a leaf, ingestion of pollen) may result in toxicosis, so all feline exposures to lilies should be considered potentially life-threatening. It should be noted that not all plants with “lily” in the name are members of Liliaceae.

Affected cats often vomit within a few hours after exposure. Within 24 to 72 hours of ingestion, kidney failure develops, accompanied by vomiting, depression, anorexia, and dehydration. Elevations in BUN, creatinine, phosphorus and potassium are detectable as early as 12 hours post ingestion. Creatinine elevations may be especially high.

In severe cases, death or euthanasia due to acute renal failure generally occurs within 3 to 6 days of ingestion. When initiated within 18 hours of ingestion, decontamination (emesis, oral activated charcoal, and cathartic) and fluid diuresis for 48 hours have been effective in preventing lily-induced acute renal failure. Conversely, delaying treatment beyond 18 hours frequently results in death or euthanasia. Baseline renal values should be obtained upon presentation and then repeated at 24 and 48 hours. Because the tubular injury from lily ingestion spares the renal tubular basement membrane, regeneration of damaged tubules may be possible. In severe cases, peritoneal dialysis may aid in managing renal failure until tubular regeneration occurs (10-14 days or longer).

8.) Ice Melts

Many brands of sidewalk ice melts are on the market. The most common ingredients in these ice melts are sodium chloride, potassium chloride, magnesium chloride, calcium carbonate, and calcium magnesium acetate. A few ice melts contain urea. Cats may be exposed by walking on the ice melts themselves or by ingesting granules brought inside on the shoes of the owner’s.

Ingestion of urea is not a toxicity issue in non-ruminants. Ingestion of sodium, potassium, calcium and magnesium salts can lead to vomiting and electrolyte abnormalities. Monitor electrolyte levels and treat with appropriate fluid therapy.

9.) Liquid Potpourri

Liquid potpourri is commonly used during the holiday season. Cats are often exposed to liquid potpourri by direct ingestion from simmer pots or spills, or by rubbing against leaky bottles or simmer pots containing the potpourri, or from spilling the containers upon themselves. Oral exposures result following grooming. 

Exposure of cats to some types of liquid potpourris can result in severe oral, dermal and ocular damage.

Liquid potpourri is a combination of cationic detergents and essential oils. Cationic detergents can cause extensive systemic and local effects at concentrations as low as 2%. Local tissue injury caused by cationic detergents resembles that seen with exposure to other corrosives. In addition, cationic detergents can cause systemic toxicity including CNS depression, coma, seizures, hypotension, muscular weakness and fasciculations, collapse, pulmonary edema, and metabolic acidosis; the mechanism of these signs is not known. 

Treatment of local exposure includes dilution with milk or water, pain control (opioids), GI protection (sucralfate slurries) and supportive care (antibiotics, feeding tube). Systemic signs should be treated symptomatically (i.e. fluids for hypotension, diazepam for seizures, etc.).

10.) Alcohol

Due to their small size, cats are far more sensitive to alcohol than humans are. Even ingesting a small amount of a product containing alcohol can cause significant intoxication. Cats are attracted to mixed drinks that contain milk, cream or ice cream (e.g. White Russian, alcoholic eggnog, Brandy Alexander). Ethanol is rapidly absorbed orally and signs can develop within 30-60 minutes. Alcohol intoxication commonly causes vomiting, loss of coordination, disorientation and stupor. In severe cases, coma, seizures and death may occur. Cats who are inebriated should be monitored by a veterinarian until they recover.

 Hope everyone has a safe and happy holiday season!

Stomach Tacking

I have seen a few Great Danes come through the office lately, so I thought I would discuss stomach tacking (gastropexy).  Large breed dogs with deep chests (Great Danes, Irish Setters, Saint Bernands, etc) have a lot more room in the front part of their abdomen that allows for more movement in the stomach and ultimately makes them prone to gastric dilatation and volvulus (GDV or bloat).  

The exact cause of GDV is unknown, but many things can predispose to the condition including

1.) rapid eating

2.) eating one large meal daily

3.) overeating and overdrinking

4.) heavy exercise after eating

5.) conformation of the dog

A dog who has GDV will typically be anxious, may be drooling, have a distended abdomen, and are retching without producing anything.  The condition quickly becomes an emergency as the twisting of the stomach compromises blood return to the heart leading to shock.  The treatment involves immediate treatment of the shock (with fluids and pain medications) and then de-rotating the stomach.  Measures can be taken without surgery including passing a tube to deflate the stomach or passing a needle into the stomach through the body wall, but in most cases surgery will eventually be needed.  Even with surgery it is not guaranteed that the pet will pull through because if blood flow is compromised long enough you may get tissues that die and become infected.

X-ray image of stomach with GDV

The surgery involves deflating the stomach, placing the stomach back into normal anatomical position, and then permanently tacking the stomach to the body wall (which prevents recurrence of GDV).  There are many different procedures to tack the stomach; however, I typically perform a simple incisional gastropexy.  This involves making an incision into the outer portions of the stomach and then making a corresponding incision into the body wall.  The incision is then sutured together using two parallel lines of suture material.  The suture material will initially hold the stomach and body wall together, but eventually scar tissue will form and permanently hold the surgery site together.  If caught early enough, many dogs can do well; however some dogs may need more aggressive surgery (removal of a portion of the stomach, accompanying splenectomy) if the condition goes on long enough.

Tacking stomach to body wall

Because of deep chested breeds risk for GDV later in life, some owners may consider performing a preventative gastropexy.  This involves performing the gastropexy before a GDV occurs (typically done during a spay or neuter procedure).  There are some minimally-invasive techniques involving laproscopy, but not all veterinarians can perform these and the cost will likely be more.  A conversation about this procedure with your veterinarian should be made when the puppy is young, so a plan can be made for performing the gastropexy.

Kidney Disease

What are the functions of the kidneys?

The kidneys play a vital role in the body, participating in a number of processes including removing waste products from the body, regulating water balance in the body, regulating calcium and phosphorus levels, and producing certain hormones for the body.  Blood that passes into the kidney is filtered through thousands of small structures called nephrons where waste products are removed and excessive water is released. 

What is chronic kidney disease?

Chronic kidney disease (CKD) is not a singular disease, but more a catch all term for kidneys that are not functioning at full capacity.  The underlying cause for this could include a number of different conditions including:

• Congenital malformation of the kidneys
• Chronic bacterial infection of the kidney (pyelonephritis)
• High blood pressure (hypertension)
• Diseases of the immune system (i.e. Lupus)
• Recovery from acute kidney disease (toxin, infection, etc) leading to chronic disease

In many cases we do not figure out the exact cause of kidney insufficiency, but treat the end result.

Signs of chronic kidney disease:

Pets with chronic kidney disease can manifest many different clinical signs including:

• drinking too much (polydipsia) and urinating large volumes of urine (polyuria)
• vomiting and/or diarrhea
• lack of appetite and weight loss
• general depression related to the elevation of waste products in the blood (uremia)
• anemia resulting in pale gums and weakness due to a low blood count
• overall weakness from low blood potassium         

How is chronic kidney disease diagnosed?

If a pet is having clinical signs consistent with kidney disease, then some tests will be recommended to evaluate kidney function.  A combination of blood work and urine evaluation is used to give a good indication of kidney function.  Two blood values are of particular concern when evaluating kidney function (Creatinine and Blood Urea Nitrogen (BUN)).  Elevations in these values could indicate that the kidneys are not functioning well. 

If creatinine elevations are seen, then the urine is also evaluated.  In particular, we are looking at the concentration of the urine.  Normally, the kidneys try to maintain proper water balance in the body.  They do this by reabsorbing water and maintaining it in the body.  When the kidneys are functioning properly they will make more concentrated urine.  If the creatinine or BUN is elevated and there is dilute urine, then this indicates that the kidneys are not functioning properly and may have chronic kidney disease.  There is also a staging system (stage 1-4) to help indicate the degree of damage to the kidneys

STAGES	CLINICAL SIGNS	FASTED PLASMA CREATININE mg/dl (umol/l)assessed on at least 2 occasions in the stable patient		EVIDENCE FOR RENAL DISEASE
		DOG	CAT
I	Absent but patients should be substaged with urine protein creatinine ratio and blood pressure measurements	< 1.4 (<125)	< 1.6 (< 140)	Inadequate urine concentration, renal proteinuria, or abnormal renal architecture based on palpation, imaging, or histopathology
II	Usually mild or absent but substage as noted above	1.4-2.0 (125-179)	1.6-2.8 (140-249)	As for stage I
III	Usually present and may be related only to kidneys. Substage as noted above	2.1-5.0 (180-439)	2.9-5.0 (250-439)	As for stage I in addition to clinical signs
IV	Present, but may have extra-renal signs. Substage as noted above	>5.0 (>440)	>5.0 (>440)	As for stage I in addition to clinical signs

Other changes on blood work and urine could include:

• Non- regenerative anemia
• Increased phosphorus
• Low potassium levels
• Calcium is often normal but can be elevated in some pets with CKD and rarely is decreased
• Protein or bacteria in the urine

Other tests may also be recommended including:

1. Abdominal radiographs (x-rays) or ultrasound to evaluate kidney size
   What might this test show?  The kidneys in pets with CRD are usually small reflecting the death of a large number of nephrons. If the kidneys are large then certain causes for the CKD should be considered such as lymphoma (cancer) of the kidneys, or an uncommon disease called amyloidosis. Some pets with signs of kidney disease who have large or normal sized kidneys may have acute kidney failure rather than CKD. The treatment and prognosis for pets with acute kidney disease differs from the treatment and prognosis of pets with CKD.
2. Bacterial culture
   What might this test show?  Bacterial infection is not a common cause of CKD but pets with CKD may develop a bacterial infection as several aspects of the pet's immune system may be less functional when the kidneys are failing.  If white blood cells are observed on microscopic examination of the pet's urine, a bacterial culture of the urine should be obtained.
3. Urine protein/creatinine ratio
4. Blood pressure

What are the treatment options for my pet?

Unfortunately, chronic kidney disease is a progressive disease and is not curable.  However, there are many options available to help treat symptoms and signs associated with kidney disease.  There is no treatment combination that is standard for every pet and many times incremental addition to medications is needed as the disease process progresses.  In some cases, pets may need to be hospitalized for a period of time to replenish fluids and in other cases pets are sent home with conservative treatments.  I will list treatment options available, but remember that an individual pet may not need all these treatments.

• Diet modification:  Studies have shown that pets switched to a protein restricted (high quality protein), phosphorus restricted diet have a higher quality of life, fewer uremic crises, and may live longer than pets fed a regular maintenance diet.  There are many commercially available, prescription diets that meet these standards. 
• Phosphorus binders: Even with phosphorus restricted diets some pets still have elevated phosphorus levels.  In these cases, supplements can be added to the food that help bind more phosphorus and restrict levels even more
• Hypertension medications: High blood pressure often accompanies kidney disease and can lead to further damage to the kidneys.  Monitoring for hypertension and adding anti-hypertensive medications (amlodipine, ACE inhibitors) when present may be warranted in some pets.
• Stomach protectors: Build-up of uremic toxins can lead to stomach upset and inappetence.  Protecting the stomach lining with medications that lower the acidity of stomach contents can be helpful.  Medications can include antacids (famotidine or ranitidine), protein pump inhibitors (omeprazole), or stomach lining medications (sucralfate).
• Anti-nausea medication: Pets may also be inappetent because of nausea.  Cerenia or metoclopramide are examples of anti-nausea medications.
• Omega 3 fatty acids: Supplementing with fatty acids has been shown in some studies to improve survival in pets
• Anemia medications: The kidneys produce a hormone called erythropoietin that signals the bone marrow to make more red blood cells.  With kidney disease, this hormone may be depleted, so anemia develops in patients.  There are commercially available erythropoietin supplements that can be given to increase red blood cell counts.  Pros and cons of this medication should be discussed prior to starting the medication.
• Fluid supplementation: Since diseased kidneys are unable to concentrate urine properly, a pet will lose an excessive amount of water in the urine.  Making sure that water is always available and promoting water consumption is important.  In cases where a pet is not keeping up with fluid loses, either periodic subcutaneous fluids (can be done at home) or intravenous fluids may be necessary.
• Potassium supplementation: Excessive potassium is lost with diseased kidneys, which can lead to loss of energy.  Adding a potassium supplement may be needed.
• Calcitriol: Calcitriol is the active form of vitamin D and helps with regulation of calcium and phosphorus.  It is produced in the kidney, so may be decreased in patients with chronic kidney disease.  To help combat renal secondary hyperparathyroidism, calcitriol may be instituted.  Careful and periodic monitoring of calcium and phosphorus levels is recommended. 

As discussed earlier, not every pet needs every treatment and your veterinarian will evaluate blood work and clinical signs before recommending certain treatments.  Also, some pets are more amenable to treatment (especially in the case of cats) as multiple medications may be needed in a day.  Individual owner circumstances can also dictate how aggressive treatment might be.  With cats, combining multiple medications into a single gel cap may be easier than administering multiple medications at a time.

Goal of therapy:

As chronic kidney disease is not curable, our goal is to provide a good quality of life as long as we can.  Some owners may elect to only change the diet in response to diagnosis, whereas others may add as many medications as reasonable and possible to help their pet.  The goal is to find the right balance for both the owner and the patient.  With proper care some pets with early kidney disease can still live a great quality of life for years.

For more information from the perspective of an owner please visit http://www.felinecrf.com.

Parvovirus

I have recently treated a couple of cases of parvovirus and have had a few scares where the owner suspected parvovirus, so I thought it would be a good idea to discuss the virus and how we can prevent and treat the infection.

Parvovirus, as its name implies, is a virus that attacks rapidly dividing cells in dogs.  Two such areas where cells like this occur in the body are the gastrointestinal tract and bone marrow.  The virus attacking these areas leads to severe diarrhea, vomiting, and a decrease in white blood cells (which usually help to fight off infection).  Without treatment a majority of dogs will die from dehydration and infection.  Even with treatment, some animals may not survive.  It hits puppies particularly hard as their immune system is not fully developed and their ability to fight infection is low.  Un-vaccinated adults can also become infected, but may respond to treatment better since their immune system is usually fully developed.

The virus is picked up when a dog ingest infected soil or other contaminated materials.  It is a very hearty virus and can live in the environment (even harsh conditions) for over a year, so may be prevalent in areas of heavy dog traffic.  After the virus is ingested it replicates in the lymph nodes and then escapes into the bloodstream eventually ending up in the intestinal tract and bone marrow.  Infected dogs will typically have acute cases of vomiting, diarrhea, inappetence, and weakness.  In many cases, blood will be seen in the diarrhea or even the vomit.  Most vets have a good bed-side test for parvo that uses a rectal swab and gives a result in less than 10 minutes.

Because it is a virus, there is not much we can do besides provide supportive care to the pet while the virus runs its course.  Supportive care usually involves hospitalization with fluids, antibiotics, vitamins, nutritional support, and pain management.  If finances allow and it is available, some veterinarians will also treat with plasma that is rich in proteins and electrolytes.  In addition, some vets are using an anti-viral medication called Tamiflu (used against human influenza cases) to help treat parvo cases.  The medication does nothing against the parvovirus, but likely helps prevent the secondary infections that are seen with the cases.  Unfortunately, even with the most aggressive supportive care some dogs may not survive the infection.

The good news is there is a good vaccine to help protect against the virus.  Vaccinations typically start around 6 weeks of age and are given every 3-4 weeks until 16 weeks.  Then, the vaccine is boosted at a year of age.  The parvo vaccine is typically part of the "distemper vaccine" series which includes multiple viruses.  Prior to 6 weeks puppies have some protection if they were able to ingest enough colostrum (mother's milk for the first 24 hours).

So the moral of the story is to make sure that your pet starts vaccinations at 6 weeks of age to prevent this aggressive disease.

Glaucoma

What is Glaucoma?

Put simply, glaucoma is an increase in the pressure inside the eye.  The big question is what is causing the increased pressure.  Before talking about this, let’s talk a little about the inside of the eye.  The eye can be divided into structures in front of the lens and behind the lens.  The globe of the eye behind the lens has a chamber that is filled in with a thicker material called vitreous humor.  In front of the lens the eye contains a thinner material called aqueous humor.  Eye pressures are the pressure inside the aqueous humor.  The aqueous is produced by the ciliary epithelium next to the len.  It then flows forward from the posterior chamber through the iris opening into the anterior chamber and then finally drains out through the trabecular meshwork into the aqueous plexus (and back into the blood stream).  The production of aqueous and its drainage is typically well regulated, but when the production exceeds drainage, pressures rise and glaucoma results.

 What are the clinical signs of glaucoma and how is it diagnosed?

When pets have glaucoma you can notice a number of different signs including redness of the eye, abnormal blood vessels on the eye, different sized pupils, squinting, pawing at the eye, and vision problems.  The diagnosis of glaucoma is fairly straightforward and involves measuring the pressures of the eye and documenting an increased eye pressure.  Most veterinarians have a tool called a Tonopen that accurately and quickly measures eye pressures.  The eye is first numbed; then the Tonopen is pressed against the eye multiple times and records the pressure.  Normal pressures for dogs and cats are between 10-25 mm Hg.  Individual pressures above this confirm glaucoma or a major difference (>8 mm Hg) between pressures in either eye may indicate a problem. 

What causes glaucoma?

The causes for glaucoma can be divided into two major categories: primary versus secondary.

1. Primary glaucoma typically means there is an inherent change (typically breed related) in the drainage angle of the eye that causes reduced drainage of aqueous.  A majority of these are caused by abnormal formation of the drainage angle of the eye that results in a narrower angle and poor drainage (closed-angle).  A smaller subset appears to have a normal drainage angle, but the drainage is still impaired (open-angle).  Breeds where primary glaucoma is common include Cocker Spaniels, Basset Hounds, Schnauzers, Beagles, Poodles, as well as many others.
2. Secondary glaucoma occurs when other eye problems occur that alter the drainage of aqueous.  This may occur if the drainage angle of the eye becomes blocked (due to inflammation, cancer, cyst) or the iris opening becomes blocked (lens luxation or chronic inflammation of the anterior eye chamber).  Long term treatment for this glaucoma is more about treating the primary cause while managing the secondary glaucoma.

How do we treat glaucoma?

The first question to ask when treating glaucoma is whether the eye is still visual, as this will determine what options are available for treatment.  Also, with secondary glaucoma, it is important to treat the underlying cause as this may ultimately fix the problem.

1. Visual Eyes: The first goal for visual eyes is to decrease the pressures as quickly as possible.  The longer the pressures stay elevated the better chance at long term damage to the retina and subsequently vision. 

1. Topical medications: Many topical medications are available that help decrease the pressure of the eyes.  With severe cases of glaucoma multiple medications are started that work in different ways.  In most cases of sudden, severe primary glaucoma a medication to open the drainage angle (latanoprost) along with medications to decrease aqueous production (dorzolamide) are used together.  An intravenous medication called mannitol may also be used that helps draw out some of the vitreous of the eye making more room for the aqueous.  Some eyes with glaucoma respond well to these medications and can be managed with just topical medications for a time.  However, a long term solution usually involves surgery.
2. Surgical options: These options are only available through a veterinary ophthalmologist and financial costs can be very high.  With primary glaucoma the recommendation will usually be a combination of two procedures.  The first is cyclophotocoagulation, which is a procedure that destroys part of the ciliary body (tissue responsible for aqueous production) with a laser.  This helps lower aqueous production.  In addition, some ophthalmologists will also recommend placing a shunt that drains the aqueous humor out into the conjunctiva.  Even with these procedures, topical medications may still be needed and complications can occur.

1. Non-visual Eyes: Once eye pressures have been high enough for long enough the retina will degenerate and the eye will become non-visual.  When this is the case, our goal is to make the pet comfortable (as glaucoma is painful).  If topical medications aren’t working, then a few procedures should be considered.

1. Enucleation: Removing the eye eliminates the problem of the high pressures and pain.  This procedure can be performed by most veterinarians; however, if a prosthesis is desired then an ophthalmologist may be needed.  Even without prosthesis, most owners are happy with the cosmetic appearance of an enucleation.

2. Intravitreal gentamicin injection: This procedure is only available for dogs and there cannot be inflammation present in the eye when performed.  Gentamicin is an antibiotic, but for this procedure is being used because it kills the ciliary body and decreases aqueous production.  It works in around 75% of dogs, but cosmetic changes (cataract, small eye, etc) may be undesirable.  It is typically used as an alternative to enucleation when cost is a factor.

What to do about the other eye?

In many cases primary glaucoma develops in one eye before the other; however, the other eye has the same changes that led to glaucoma in the bad eye.  Starting the other, non-glaucomatous eye on a topical medication can lengthen the time before that eye develops glaucoma.  The typical medications used are either dorzolamide (Trusopt) or timolol (Timoptic).

Ultrasound

Sorry about the lack of blogging recently.  With the summer, things have been a little hectic.  I wanted to take some time now to discuss a newer form of testing we have added to our clinics here in Champaign/Urbana.  We have recently started to offer ultrasound services at our clinic in Savoy.  Currently, these are limited to abdominal (stomach, kidney, liver, spleen, etc) imaging, but we hope to offer echocardiogram (heart) imaging in the future.

The question you might be asking is what is ultrasound and when might we need to use it for your pet.  Unlike x-ray, which uses radiation to take images, ultrasound uses sound waves that are directed towards organs and the machine listens for the sound reflections from these organs to make images.  So instead of just being able to evaluate the outline of the liver or intestines (such is done with x-rays), we are able to better evaluate the architecture of organs.

Above are examples of ultrasound images from the intestines of cat.  As you can see, we can observe the different layers of the intestines and effectively evaluate for any thickening of the bowel or possible obstruction.

You might ask what would be a good use for this form of technology?  There are many patients where ultrasound can be helpful.  I will just talk about a couple examples.

Some owners have cats that may vomit periodically or may be losing weight.  We start with blood work and don't find many changes.  The next step may be an abdominal ultrasound.  During the ultrasound we scan all the abdominal organs, but in this case would likely focus on the intestines and pancreas.  With the ultrasound we can evaluate the intestinal wall thickness and see whether it appears thickened.  If the intestine is thickened, we can determine which layer of the intestine is thick and then can make a list of diseases (inflammatory bowel disease, lymphoma, etc) that could be causing the problem.  We can also evaluate the pancreas to see whether any signs of pancreatitis are evident.

Another case that ultrasound may be helpful would be to evaluate elevations in a dogs liver values.  In older dogs elevations of liver values can be benign or could indicate the start of a more serious condition.  With ultrasound we can evaluate the structure of the liver and possibly get an aspirate or biopsy sample to evaluate for a more serious condition.

Ultrasound on a dog

The nice thing about ultrasound is it that it is a non-invasive procedure.  We only have to shave the underside of the belly (and possibly sedate your pet) to get good images and a possible diagnosis.  Like any test, it may not give us all the answers, but many times can give us a lot more information that can benefit your pet greatly.

Ultrasound image of a kidney

Please let me know if you have any questions.

Oh my gosh, is that a Tick?

Nothing creeps people out more than finding a tick on their pet (or themselves for that matter).  Because of pets hair it can be difficult to find ticks on your pets until they have been feeding for a few days and become engorged.  When this is the case we can get concerned because ticks do transmit several diseases that are transferred to animals after the tick feeds.  First, lets talk a little about the tick life cycle.  Ticks have 4 life stages: egg, larva, nymph, and adult.  Depending on the species this cycle can take a year to 2 years to complete.  The larva, nymph, and adults all can feed on mammals.

In Illinois there are numerous tick species, but the most common that may be encountered are the American dog tick, lone star tick, blacklegged (deer) tick, brown dog tick and winter tick.  Most species are active in the spring and early summer and then are more dormant throughout the rest of the year (however, ticks can be active any time of year when temperatures are above 45 degrees).  Ticks hang around on the tips of grasses and scrubs (not trees) and when the plant is brushed by a pet or person they crawl onto the host.  Using their mouth pieces they attach to the skin and feed on the blood of the host.  When they bite, ticks typically secrete saliva that has anesthetic properties, so the bite is not felt.  Ticks can feed for several days and become quite engorged prior to falling off.

Why is it important to try and prevent tick bites?  When ticks feed on blood, they can also transmit diseases to the host they are feeding on.  Common diseases that are passed include Rocky Mountain Spotted Fever, Lyme disease, Erlichia, Anaplasmosis, as well as other blood-borne pathogens.  Many of these organisms attack red blood cells, white blood cells, blood vessel lining cells and other cells in the body and can have serious, and possibly life threatening consequences.  So, it is much more advantageous to prevent attachment of ticks then to treat the diseases that may be passed along by a tick bite.  

How do you go about preventing tick exposure.  There are numerous products available that help repel ticks.  Many of the products are topical spot-on liquids that go on the back of the shoulder blades and last for around a month.  These products also typically protect against fleas.  Frontline and Advantix have been around for awhile and work fairly well.  Be cautious with using Advantix (dog only product) in a household with cats because it contains a permethrin which can cause problems (seizures, tremors) in cats.  Merial (the maker of Frontline) recently came out with another product called Certifect, which is the active ingredient in Frontline plus an added ingredient (amitraz) which helps repel ticks more strongly.  

There is also a very good product called Preventic, which is a collar containing amitraz that is put around the neck.  It starts working within 24 hours of application and lasts for 3 months.  This collar works very well and we don't see many side effects associated with it.  Occasionally, owners of pets with a Preventic collar may have a skin reaction when petting their animal.  Also, if ingested the collar can cause major issues, so if you have a pet who is good at getting collars off, this may not be the product for you.

What if you find a tick on your pet?  If the tick is not attached, simply remove the tick and dispose of it outside or in the garbage.  We will put them in alcohol to kill them prior to throwing them out.  If they are attached, then the tick should be removed.  Grasp the head of the tick as close to the skin as possible and pull straight out.  If you are not comfortable doing this, then contact your veterinarian and they can do it for you.  If the tick is engorged and you are in an area where ticks carry diseases (see above), then watch your pet closely for any signs of sickness (inappetence, lameness, lethargy).  Some veterinarians will start prophylactic antibiotics in this situation to treat tick-borne diseases.  Others may wait and suggest running tick-borne antibody titers in 8-12 weeks after exposure.

Ticks can cause huge problems, so it is best to prevent them in the first place.  Let me know if you have any questions.

So Many Choices...

With the start of Spring (and finally spring weather) it is always a good time to review heartworm and flea protection for your pet.

Heartworm disease is a parasitic infection that is passed by mosquiotoes when they feed on your pet.  Any pet is susceptable even if they don't spend a lot of time outdoors.  If you can imagine those warm summer nights sitting out on the porch (even if just for 5 minutes) and coming back in with what seems like hundreds of mosquito bites.  Well, those mosquitoes don't just feed on you and will look for any warm body to feed on; like your pet.  That being said, it is important that your pet (in particular dogs, but cats as well) be on a montly heartworm prevention.

Same goes for fleas.  You can see the previous post to get a more detailed discussion on fleas.  Basically, the moral of the flea story is it is much easier to prevent them than to treat your house after they have gotten out of control.  Fleas love to feed and love to multiply and if your pet is not protected they are a prime target for fleas.  Even if your pet only goes out for a short time (let's say to use the bathroom), that is long enough for a flea to hop on them and then come into the house and lay its eggs.  Because of this we recommend all pets be on a flea prevention.

Now that you know your pet should be on a heartworm and flea preventative, what preventative should you use?  Recently, it seems like there has been an explosion of different products available for prevention of heartworms and fleas.  Our clinic focuses on a couple of products that we believe work well. 

The first is a product called Trifexis.  The nice thing about this product is it prevents most of your major parasites all in one oral monthly tablet (Heartworms, Fleas, and Intestinal Parasites).  It is well handled by dogs with vomiting being the most common side effect.  We feel that it works very well for fleas; killing adult fleas in as quickly as 30 minutes.  The heartworm prevention in the medication is the same active ingredient as Interceptor, which has proven effective for a very long time.  The one downside with this medication is that it does not prevent against ticks; however, we have been adding in a Preventic collar in dogs at risk for tick exposure.

The other product or combination of products that we use is Heartgard and Frontline.  Heartgard prevents heartworm disease along with intestinal parasites.  It has been around for a long time and works very well.  It comes in a flavored tablet, so administration is easy.  Frontline is a topical flea and tick preventative (goes on the skin over the back).  It also has been around for a long time and works well, but you need to make sure that it is applied correctly.  It uses the natural oils of the skin to spread, so you have to make sure you do not bathe your pet or allow them to swim two days before or after application.  After that time it is water-resistant.  You also have to make sure that when applying the medication it get down to the skin and not just on the hair.  Both products are administered on a monthly basis.

There are numerous other products available, which likely are effective as well.  It is important that your pet be on one of these products as heartworms can be devastating to an animal and fleas not only are a nuisance, but can spread disease as well. 

Why a 1 year vaccine?

There are a few vaccines that we deem as "core" vaccines that are highly recommended in cats.  One in particular is a vaccine against the rabies virus.  Fortunately, in most area of the United States (Illinois included), rabies is not a huge problem and only few cases of rabid animals and very rare cases of human exposures are reported.  One of the main reasons for this is the implementation of rabies vaccines in our pet population, who can be carriers and propagators of the disease.  In areas were mandatory rabies vaccination of pets and wild dogs is not required (such as India) rabies is a huge problem with over 20,000 people killed each year.



You may say that my cat is indoor only, so I don't think they need to be vaccinated as they won't be exposed to any other potential carriers of the disease.  This may be true, but in our area the most common carrier of the virus are bats, which on occasion to get in the house and may cause exposure to your pet.  Because of this, the public health concern, and the fact that County laws requires it, we highly recommend that your cat be vaccinated against rabies.

Okay, now that we have decided that we should vaccinate your cat for rabies, what is the best vaccine to use?  There are a few vaccines available that are effective in protecting your cat from rabies.  The one that we recommend is the Merial PureVax vaccine.  This uses a recombinant canarypox-vectored vaccine technology.  Basically what that means is they take little snipets of the rabies virus' DNA and implant them into the DNA of a canarypox virus.  Once this is injected under the skin, your cat's body recognizes the canarypox virus as a foreign virus, so mounts an immune system response to fight off the virus.  In doing so, the body also mounts a response to the snipets of the rabies DNA, which gives your cat protection against rabies.  We rarely see side effects to the virus and are very happy with the results.  The one downside to this vaccine is that it is only labeled for protection for 1 year, so has to be boosted annually (as County laws are strict about following the labeled protection).



Why do we use the 1 year vaccine over available 3 year vaccines?  The main reason that we do this is safety.  In the late 90's and early 2000's, the veterinarian community noticed an uptick in aggressive skin tumors call fibrosarcomas.  When looking at cats with these tumors they noticed that many of them were occurring over the shoulder blades where most vaccines were previously given (lots of loose skin here that made for easy administration).  Pathologists looking at these tumors under the microscope also noticed that they saw some foreign material that could be associated with previous vaccines.  Many vaccines use a slightly different technology for vaccines where a portion of killed virus is added with an adjuvant and injected under the skin.  The adjuvant is a caustic substance (usually not disclosed by the vaccine maker) that is meant to stimulate the immune system to react and subsequently react to the killed virus (which is typically too weak to stimulate the immune system itself).  It was hypothesized that the adjuvant was doing such a good job that it caused chronic inflammation in these areas that eventually would end up transforming into cancerous cells.



Planning for removal of large tumor on the back.

 These tumors are very aggressive and tend to metastasize (spread to other organs like the lungs) readily and without extensive surgery (sometimes removing parts of the scapular bones or chest wall) tend to grow back quickly (as soon as 2-3 months).  Even with extensive surgery these tumors can recur or spread and many cats don't make it longer than 1.5-2 years after they are diagnosed.

A cat after removal of a vaccine associated fibrosarcoma

In response to these tumors, a company switched to the canarypox vaccines and we have seen a declined in these tumors.  Because of a problem with a control group during testing of the vaccine, the vaccine was unfortunately denied a 3 year label, so we are stuck with the 1 year vaccine for the time being.  However, the safety of the vaccine (in my opinion) outweighs the inconvenience that may come with a 1 year vaccine.

Please let me know if you have any questions.

Food Allergies

Now that we have discussed environmental allergies, we should discuss other possible causes of itchiness in pets, in particular food allergies.

Does my pet have a food allergy?

Diagnosing a food allergy can be difficult with pets.  The only reliable way to judge whether a pet is having a reaction to food is performing a food elimination trial which can be cumbersome and lengthy, but if an owner is committed can be very rewarding.  If your pet has itchiness throughout the year and it tends to be around the feet and ears, then a food allergy should be strongly considered.  The allergies tend to start prior to a year of age, but can start anytime throughout a pets life (even if they have been on the same diet for a long time). 

Well, does my pet have a food allergy?

If you think your pet is allergic because they are itching a lot and go to the veterinarian’s office, they will likely ask you a series of questions to get a handle of what is going on.  There are some common criteria that food allergies fit into:

1.      Young age of onset: Most pets with food allergies start showing symptoms prior to one year of age.  In a dog who develops itchiness after 6 years of age with no history of previous problems, a food allergy should also be suspected.

2.      Time of year: A food allergic pet should be itchy during all times of year, since they are being constantly exposed to the allergen.  Some pets may show worsening symptoms during certain times of year because they have a concurrent airborne allergy.

3.      Response to steroids: Food allergies typically do not respond well to steroids.  In early stages of food allergies, the itchiness may improve.  If your pet once responded well to steroids and now doesn’t, then a food allergy should be suspected.

4.      Areas of itchiness: The typical adage for food allergies is, “ears and rears.”  That being said the distribution can be elsewhere including

5.      Concurrent gastrointestinal signs: Around 20% of food allergic dogs will also have consistent or intermittent gastrointestinal signs (vomiting or diarrhea).

We suspect my pet might have a food allergy, now what?

The “gold standard” for diagnosing a food allergy is an 8-12 week food elimination trial followed by rechallenging your pet with their previous food.  If your pet improves on the food trial and then symptoms reoccur after reintroducing their previous food, then a food hypersensitivity is diagnosed.  The offending agents in the food that cause problems are the proteins.  Common proteins that cause problems include beef, milk, lamb, wheat, corn, chicken egg, soy, chicken in dogs, and adding tuna and salmon to the list in cats. 

Prior to starting a food trial it is a smart idea to compile a list of foods that your pet has been exposed to in the past.  This includes any commercial dog diets, table scraps, treats, supplements, and drugs (particularly heartworm prevention).  We do not want to use a diet that has a protein source that your pet has already been exposed.  We also want to know whether your pet has unsupervised access outside as some pets forage outside and may be exposed to things that you may not know about.  Once we have a good idea about previous exposures we can make suggestions on foods for a food elimination trial.

What is a food elimination trial?

An elimination trial is a period of 8-12 weeks where a “hypoallergenic” diet is fed exclusively to your pet and their itchiness and skin issues are monitored and graded for improvement.  It is important that during this trial ONLY the chosen diet is being fed.  Your pet should not have any treats (table scraps, biscuits, popcorn, etc) during this time and any flavored medications (in particular heartworm preventatives) should be stopped (if during the summer a topical or unflavored heartworm prevention should be used).  

ONLY the “hypoallergenic” diet should be fed during this time.  If your pet has a food allergy and the diet chosen is the proper one for him/her, then you should only see improvement on the diet trial.  If your pet ever gets worse symptoms (AND you are sure that they did not receive any outside food source), then the food trial should be stopped and a different diet should be chosen.  Improvement are not always immediate, so we suggest giving a minimum of 8 weeks to see whether any improvement is noticed.

If your pet improves on the food and is doing significantly better, then we suggest following up with a “challenge” of their previous food.  Prior to starting the new diet, save some of their old food and freeze it for the challenge.  The “challenge” involves reintroducing the old diet.  If your pet has recurrence of the itchiness and skin issues (usually show up between 15 minutes after eating, but some can take as long as 2 weeks), then the food allergy is diagnosed and one of the protein sources from the old diet is the offending allergen.

What food should I use for the elimination trial?

There are a few routes that can be taken for the type of food used during the trial:

1.      Homemade diet: The home cooked diet is a simplified diet of one protein source (1 part) and one carbohydrate source (2 parts).  Although this is not balanced (minerals and vitamins), it is not meant to be fed long term and will not cause major problems if fed for the 8-12 weeks.  Protein sources currently available for home-cooking include kangaroo, camel, ostrich, emu, bison, elk, venison, rabbit, duck, fish, and whole chicken egg.  Carbohydrate sources can include oatmeal, quinoa, rutabaga, sweet potato, and white potatoes.  Ideally, a protein and carbohydrate that your pet has not been exposed to should be used.  This simplified diet eliminates any other food source and is very effective.  Once we have identified that your pet is food allergic (improvement on this diet), then we can seek out a commercial dog diet with similar ingredients that can be used or consult with a veterinary nutritionist to help balance the homemade diet so your pet will not be vitamin or mineral deficient.

2.      Prescription novel protein diet: These diets use a similar idea as the homemade diet as they use protein and carbohydrate sources that are novel.  Common ingredients include duck, kangaroo, venison, potato, green pea, or rice.  Companies offering these diet include Royal Canin, Science Diet, and Purina and these diets have to be obtained through a veterinarian.  The companies are very throughout about preventing cross contamination of foods during production and guarantee that the proteins listed are the only ones in the diet.  The advantages of these diets are the convenience of not having prepare the diet and knowing that there is no cross contamination.  The disadvantage is the price which typically run $33 for an 8# bag, $64 for an 18# bag, and $84 for a 28# bag. 

3.      Prescription hydrolysed diet: These diets are a little different in that instead of using novel proteins they process the proteins so they are very small and should not cause an allergic reaction.  They have similar advantages and disadvantages as the prescription novel protein diets.  Some pets do also have some gastrointestinal issues (mostly diarrhea) with these diets.

4.      Over-the-counter limited ingredient diets: These diets are similar to the prescription novel protein diets in that they use protein and carbohydrate sources not typically seen in commercial diets.  The disadvantage is that there may be some cross contamination during the production process that can leave small amounts of other common proteins (beef, chicken, etc) in the foods.  These proteins can be at high enough levels to continue to cause adverse skin problems.  The advantage is that they are typically cheaper than the prescription brand foods: $15 for 5# bag, $40 for #15 bag, and $58 for a 28# bag.  If choosing this option, I do like the Natural Balance Limited ingredient line.

Just because you start on one diet it doesn't mean that you have to continue on this diet forever.  You can use a prescription novel protein diet or homemade diet for the diet trial and if you see improvement, we can try to find an over-the-counter alternative that may do a similarly good job.  Using the prescription diet or homemade diet first at least makes cross-contamination from other proteins less likely and we can rule out a food allergy much easier.

I am not seeing improvement on the food trial, now what?

Please be patient with the food trial.  It can sometimes take 12 weeks to see a major improvement in skin issues with dogs on a new diet.  Try to make a conscience effort to grade your pets skin issues every 2 weeks.  You should see gradual improvement in itchiness over time if the food trial is working.  If there is ever a worsening of signs (AND you are certain your pet didn't get any other food and it is not the time of year for seasonal airborne allergies) then your pet may not have a food allergy or the diet being used is not appropriate.  Please contact your veterinarian to discuss things further.

Here is a website that discusses common pitfalls of food trials.