OSTEOSARCOMA (BONE CANCER)

WHAT IS IT?

Bone cancer can strike relatively young dogs, even as young as 5 years.

While it can affect any bone in the body, 75% to 85% of these cancers are found on the legs at the shoulder, wrist or knee joints as shown in the illustration.

The disease begins inside the bone, initially causing an intermittent lameness but eventually causing constant, deep and severe pain after just a short period (1-3 months, most likely).  The bone weakens and can eventually break with minimal trauma or pressure (a "pathological" fracture).

The following x-rays illustrate the bone changes caused by osteosarcoma

HOW IS IT DIAGNOSED?

Your vet will very likely recommend an x-ray to distinguish the different causes.  Depending on the stage of the osteosarcoma, the x-ray itself can be diagnostic.  Early cases may be more ambiguous and require a follow-up x-ray in a few weeks.

If there is doubt, the definitive diagnosis can usually be obtained through bone biopsy. Other diseases causing similar changes on an x-ray include some bone infections, other types of bone tumors, and fungal infections of the bone.

CAN IT BE TREATED?

Osteosarcoma is a terrible disease and managing it requires a strong commitment, both financially and emotionally.

Treatment addresses two aspects of the disease: the pain and the cancer itself.  The pain of bone cancer is thought to be greater than almost any other disease, and it is continuous, non-stop, relentless, and never-ending.  Even the strongest pain medications can fail to control this kind of pain, so it is imperative that you and your vet aggressively manage this part of the disease. Together, you must recognize when pain is no longer controlled, so you can make an appropriate quality-of-life decision.

TREATMENT OPTIONS

Medical pain relief only - combinations of pain medications to control pain, followed by euthanasia when they fail to do so. The caution here is the difficulty in objectively judging pain.  It's hard to know how much our pets are really suffering, and it's easy to think because they don't scream, they don't hurt.  MOST DOGS SUFFER SEVERE PAIN IN SILENCE.  With this treatment option, life expectancy is 4 months, although pain control may well fail long before that.  You must find the courage to face appropriate timing of euthanasia.

Amputation and pain relief - while seemingly drastic, amputation provides pain relief to 100% of the dogs who receive it.  With amputation alone, the life expectancy remains at an average of 4 months, but the quality of life is improved.

Amputation and chemotherapy - this improves the life expectancy, although does not cure the disease.  With this the average life expectancy is 1 year.

Limb sparing surgery - a new technique adapted from human medicine and done at some referral centers.  The cancerous bone is removed and replace with grafted bone, and the nearest joint is fused.  This is only done on the wrist area at this time.

Radiotherapy to control pain - the tumor is irradiated and this can provide about 4 months of pain relief in about 65% of the patients.

Euthanasia - eventually it is likely that treatment will fail, the pain will overcome your Greyhound again, and the cancer will prevail. When that day comes, the final gift you can give your pet is to relieve him/her of an impossible struggle.  Euthanasia is the beginning of your grief, but it is the end of their suffering, and with this disease it is something that must be faced.

THE FUTURE

Studies are underway to try to understand and treat this disease more effectively.  One aspect of this is a genetic study being done at the University of Michigan.  If your Greyhound develops osteosarcoma, please consider the donation a small blood sample to this study.  We need all the information we can get to eventually be able to cure these cancer victims.

http://www.grassmere-animal-hospital.com/osteosarcoma.htm

Tubal ligations and vasectomies for dogs?

In case you didn’t already guess it, the topic is considered a tad taboo among veterinarians. At the very least, it’s controversial. That’s because the basic spay and neuter do the job well. Very well, in fact. Unfortunately, they’re also invasive. In the case of the spay, VERY invasive.
All the same, we spay and neuter safely all the time. Typically , we spay by cutting out the ovaries and the uterus, and neuter by removing both testicles. And we’re good at it. VERY good at it. But that doesn’t mean it’s the only way to sterilize a pet. It doesn’t mean other approaches shouldn’t be considered––not for dogs, anyway.
(Additionally, please read why cats should always be spayed and neutered at six months or before in yesterday’s post.)
That’s because dogs can theoretically wait on a spay or neuter (yesterday’s post also covered this subject), but they can’t necessarily wait on the issue of sterilization––not as long as the pet overpopulation problem continues unabated, not as long as more and more municipalities adopt laws that actually require pets to be sterilized by as early as four months of age (more on this next week).
As long as these facts, cultural norms and trends persist, some form of sterilization for pets will be considered routine. But when a complete gonad removal (a in a spay or neuter) doesn’t mesh with what you and your veterinarian deem best for your dog, other less invasive alternatives may suffice––temporarily at least.
Hence the concept of vasectomization and tubal ligation.
These easy surgeries require tiny incisions and cause minimal pain––nothing compared to their standard counterparts. And they do the trick, sterilizing effectively, efficiently, and irreversibly.
So why have you likely never heard of this? It’s all about the veterinary community’s resistance to change its basic standards. Our medical culture still deems it unwise to sterilize without removing the actual source of the hormones––the gonads. The benefits of early gonadectomy still outweigh the risks of waiting (though that seems to be changing for at least some dogs).

Moreover, when we know that all dogs are best served fully spayed and neutered at some point (once they’re old enough to suffer a higher risk of reproductive diseases prevented by spays and neuters), it seems kind of wrong to force a pet to undergo two surgeries instead of just one.
In other words, pets vasectomized or receiving tubal ligations early on to prevent reproduction will also need a spay or neuter later on to prevent disease––with all the risks that entails (spays done later in life are much bigger procedures than when they’re done early).
Nonetheless, given the mandates for early spays and neuters cropping up countrywide, I can’t help but argue that some pets are best left "intact." If not because early spays and neuters might not be best, then because athletes, other competitors and some service dogs might be better at what they do when left "whole"––with a simple snip, snip somewhere very discreet.
It’s certainly not for all pets (indeed, maybe only for a small minority), but it’s nonetheless a bonus to have another option, right?





Reference

http://www.petmd.com/blogs/dailyvet/2009/July/31-4488

Emergency Case of the Week

Anorexia in Pets

Anorexia or lack of appetite is a common complaint among pet owners. It is one of thefirst signs that owners notice when their pet is becoming ill and is a common reason for presentation of animals to the veterinary clinic. Unfortunately, lack of appetite is not a sign that is specific for any one disease or illness-there are multiple causes. The remainder of this article will discuss some of the reasons animals stop eating, some of the methods of determining an underlying cause, and some of the things that can be done if your pet decides to stop eating.

CAUSES OF ANOREXIA

Anorexia can have a multitude of causes ranging from behavioral and environmental causes to illness. While this list is not all-inclusive, some of the most common causes of anorexia in pets are listed below.

Environmental/weather changes. Hot, humid weather conditions can cause animals

to have a decreased appetite. It is not uncommon for pets to be less active and eat

less during hot summer weather. Typically, with cooler temperatures, appetite will

improve if this is the sole cause of anorexia.

Stress and depression. Things that cause a change in the animal's normal routine

can cause some animals to stop eating. For example, the loss of a companion pet or loss of a human can cause animals to be depressed/stressed and result in lack of appetite. Other stressors such as moving, adding a new pet, the presence of a new baby, or visiting guests, can also result in anorexia.

Food change. A sudden change in diet can cause animals to refuse food, especially

if food is changed to something that is less palatable than the original diet. Slow,

gradual change between diets can help eliminate lack of appetite due to a change in diet.Food intolerance and food allergy. Like people, certain types of foods can cause

GI irritation in pets. For example, fatty or greasy foods may cause a pet to experiencegas and cramping and result in a lack of appetite. Some animals can be allergic to certain proteins contained in pet foods such as chicken, beef, wheat, corn, or soy. Animals with food allergy can have signs ranging from lack of appetite to vomiting and diarrhea.

Side effects of medications. Some long-term medications, such as medications for

heart failure (not heartworm medications) and arthritis medications, can cause GI

irritation and lack of appetite. Some short-term medications, such as antibiotics,

can cause similar problems.

Picky eater/spoiled appetite. Some pets become very picky eaters and are tempted

with human foods. This can often compound a pet's refusal to eat pet foods. Some pets become spoiled with pet treats and human foods and will become too full to eat their regular food.

Fractured/damaged teeth. Excessively worn or fractured teeth can be painful and

can cause a pet to refuse to eat. Illness. Illnesses such as gastrointestinal disease, kidney disease, heart disease, liver disease, dental disease, cancer, etc. can cause an animal to stop or decrease eating. Some of these diseases can cause nausea, which will impair the desire of a pet to eat. Some of these diseases can cause painful lesions or ulcers with in the mouth that can hinder a pet's ability to eat. Some of these diseases cause weakness, which can result in a decreased appetite.

DIAGNOSIS.

Looking for the cause of appetite loss is the most important consideration of caring

for pets with anorexia. Healthy animals typically have good appetites. A thorough

physical examination of the pet, paying special attention to the oral cavity, lymph

nodes, and GI tract may provide important clues as to the cause. Diagnostic testing

such as bloodwork, x-rays, and GI endoscopy may be warranted. Specific testing based on the history and physical examination should be recommended by the veterinarian.

TREATMENT.

Obtaining a proper diagnosis is the first and most important step to treating anorexia.

Treating the cause of the appetite loss is critical for success. For example,

changing foods or adding moisture to the diet will have little or no long-term results

if the pet is suffering from undiagnosed cancer. Without determining the underlying

cause, many treatment options will be successful for short periods of time or completely unsuccessful altogether.

While you are waiting for laboratory testing results or early on in mild cases of

anorexia some general tips that can be tried to improve appetite include:

1) Moistening the food. Adding a little bit of warm water to dry food can stimulate appetite.

2) Heating food. Some animals will eat food better if it is warmed slightly. 3) Canned

food. For animals that are accustomed to dry food, canned food may perk up the

appetite. Mix small amounts of canned food with the dry food first as large quantities of canned food can cause diarrhea in pets that normally get dry food.

4) Changing brands or flavors of food. Moving to a higher quality and/or more palatable food may stimulate a pet's appetite. Again, mix small amounts of the new food with the regular food to avoid diarrhea.

5) Appetite stimulants. Some prescription medications are available

that can help to stimulate the appetite in some cases.

6) Change bowl shape/size.While this is often not successful, in some cases changing from a bowl to a plate or moving to a larger bowl can make a difference for a picky eater. 

7) Top dress food with boiled chicken and rice. While feeding human foods is not generally recommended, adding small amounts of boiled chicken and rice to the regular food may encourage a picky eater to finish his/her bowl. However, extreme caution should be used as some animals will not return to their normal diet once they have been tempted with human foods.

8)Try a nutritional supplement.

Pyometra in dogs

What is pyometra?

pyometra_1_2009Pyometra is defined as an infection in the uterus. Pyometra is considered a serious and life threatening condition that must be treated quickly and aggressively.

"Pyometra is a secondary infection..."

Pyometra is a secondary infection that occurs as a result of hormonal changes in the female's reproductive tract. During estrus ("heat"), white blood cells, which normally protect against infection, are inhibited from entering the uterus. This allows sperm to safely enter the female's reproductive tract without being damaged or destroyed by these immune system cells. Following estrus ("heat") in the dog, progesterone hormone levels remain elevated up to two months and cause thickening of the lining of the uterus in preparation for pregnancy and fetal development. If pregnancy does not occur for several consecutive estrus cycles, the uterine lining continues to increase in thickness until cysts often form within the tissues (a condition called Cystic Endometrial Hyperplasia). The thickened, cystic lining secretes fluids that create an ideal environment for bacteria to grow in. Additionally, high progesterone levels inhibit the ability of the muscles in the wall of the uterus to contract and expel accumulated fluids or bacteria. The combination of these factors often leads to infection.

What else can cause changes in the uterus?

The use of progesterone-based drugs can cause changes in the uterus similar to the estrus cycle. In addition, estrogen or synthetic estrogen drugs will increase the effects of progesterone on the uterus. Drugs containing both estrogen and progesterone are sometimes used to treat certain conditions of the reproductive system. Any intact female receiving hormones must be carefully monitored for the development of pyometra.

How do bacteria get into the uterus?

The cervix is the gateway to the uterus. It remains tightly closed except during estrus, when it relaxes to allow sperm to enter the uterus.

"If the cervix is open or relaxed, bacteria that are normally found in the vagina can enter the uterus easily."

If the cervix is open or relaxed, bacteria that are normally found in the vagina can enter the uterus easily. If the uterus is normal, the uterine environment is adverse to bacterial survival; however, when the uterine wall is thickened or cystic, perfect conditions exist for bacterial growth. In addition, when these abnormal conditions exist, the muscles of the uterus cannot contract properly either due to thickening of the uterine wall or the hormone progesterone. This means that bacteria that enter the uterus cannot be expelled.

When does pyometra occur?

Pyometra may occur in any sexually intact young to middle-aged dog; however, it is most common in older dogs.

"Pyometra usually occurs two to eight weeks after the last estrus."

After many years of estrus cycles without pregnancy, the uterine wall undergoes the changes that promote this disease. Pyometra usually occurs two to eight weeks after the last estrus ("heat cycle").

What are the clinical signs of pyometra?

pyometra-2_2009The clinical signs depend on whether or not the cervix remains open. If it is open, pus will drain from the uterus through the vagina to the outside. Pus or an abnormal discharge is often seen on the skin or hair under the tail or on bedding and furniture where the dog has recently laid. Fever, lethargy, anorexia, and depression may or may not be present.

If the cervix is closed, pus that forms is not able to drain to the outside. It collects in the uterus ultimately causing the abdomen to distend. The bacteria release toxins that are absorbed into the bloodstream. Dogs with closed pyometra become severely ill very rapidly. They are anorectic, very listless and very depressed. Vomiting or diarrhea may also be present.

Toxins released by the bacteria affect the kidney's ability to retain fluid. Increased urine production occurs, and many dogs drink an excess of water to compensate. Increased water consumption may occur in both open- and closed-cervix pyometra.

How is pyometra diagnosed?

Dogs that are examined early in the course of the disease may have a slight vaginal discharge and show no other signs of illness. However, most dogs with pyometra are seen later in the illness. A very ill female dog with a history of recent "heat" that is drinking an increased amount of water should be suspected of having pyometra. This is especially true if there is a vaginal discharge or a painful, enlarged abdomen.

Dogs with pyometra usually have a severe elevation of the white blood cell count and often have an elevation of globulins (a type of protein often associated with the immune system) in the blood. The specific gravity (concentration) of the urine is generally low due to the toxic effects of the bacteria on the kidneys. However, these changes are non-specific and may be present in any dog with a major bacterial infection.

If the cervix is closed, radiographs (x-rays) of the abdomen will often identify the enlarged uterus. If the cervix is open, there will often be such minimal uterine enlargement that the radiograph will be inconclusive. An ultrasound examination may be helpful in identifying an enlarged uterus and differentiating that from a normal pregnancy. Ultrasound changes that indicate pyometra include increased uterine size, thickened uterine walls, and fluid accumulation within the uterus.

How is pyometra treated?

"The preferred treatment is to surgically remove the infected uterus and ovaries..."

The preferred treatment is to surgically remove the infected uterus and ovaries, or perform an ovariohysterectomy ("spay"). Dogs diagnosed in the early stage of the disease are very good surgical candidates. The surgery is somewhat more complicated than a routine spay at this stage. However, most dogs are diagnosed with pyometra when they are quite ill resulting in a more complicated surgical procedure and a longer period of hospitalization. Intravenous fluids are required to stabilize the dog before and after surgery. Antibiotics are usually given for two weeks after surgery.

My dog is a valuable breeding female. Is there a treatment other than surgery?

There is a medical approach to treating pyometra, although the success rate is widely variable and not without considerable risk and potential long-term complications. Prostaglandins are a group of hormones that lower the blood level of progesterone, relax and open the cervix, and cause the uterus to contract and expel bacteria and pus. They can be used to treat this disease, but they are not always successful and have some important limitations.

1.  They cause side effects including restlessness, panting, vomiting, defecation, salivation, and abdominal pain. The side effects occur within about fifteen minutes after administration and often last for a few hours. They become progressively milder with each successive treatment. The pain may be decreased by walking or exercising the dog for about 30 minutes following an injection.

2.  There is no clinical improvement for about forty-eight hours, so dogs that are severely ill and need immediate life-saving treatment are poor candidates.

3.  Because prostaglandins cause the uterus to contract, it is possible for the uterus to rupture and spill infection into the abdominal cavity resulting in the severely life-threatening condition known as peritonitis. This is most likely to happen when the cervix is closed.

There are some important statistics that you should know about this form of treatment:

1.  The success rate for treating open-cervix pyometra is approximately 75-90% in uncomplicated cases.

2.  The success rate for treating closed-cervix pyometra is only about 25-40%.

3.  The rate of recurrence of the disease in a treated dog is generally thought to be as high as 50-75%.

4.  The chance of future successful breeding is decreased to about 50-75%. 

What happens if I don't treat my dog?

The chance of successful resolution without surgery or prostaglandin treatment is extremely low. If treatment is not performed quickly, the toxic effects from the bacteria will be fatal in many cases. If the cervix is closed, it is possible for the uterus to rupture, spilling the infection into the abdominal cavity. This will also be fatal. Pyometra is a serious medical condition that requires prompt treatment.

Reference

http://www.vcahospitals.com/main/pet-health-information/article/animal-health/pyometra-in-dogs/915

Distemper in Dogs

Distemper is a highly contagious disease caused by a virus similar to the one that causes measles in people. Worldwide, it is the leading cause of infectious disease deaths in dogs, although in the United States it occurs only sporadically. All unvaccinated dogs are at high risk of infection.

Infected animals shed canine distemper virus in all body secretions. Inhaling the virus is the primary source of exposure. The highest incidence of the disease occurs in unvaccinated puppies 6 to 12 weeks of age, at which time maternal antibodies fall below protective levels.

Half the dogs who become infected with canine distemper virus show mild signs of illness or no signs at all. The overall health of the dog has a lot to do with how ill he becomes. The disease is most severe in dogs who are poorly nourished and ill-kept.

The distemper virus tends to attack brain cells and cells that line the surfaces of the body, including the skin, the conjunctiva, the mucous membranes of the respiratory tract, and the gastrointestinal tract. The disease takes a variety of forms. Secondary infections and complications are common, partly attributable to the immunosuppressive effects of the virus.

The first signs of distemper appear six to nine days after exposure, and in mild cases go unnoticed.

First stage is characterized by a fever spike of up to 103° to 105°F (39.4° to 40.5°C). A second fever spike is accompanied by loss of appetite, listlessness, and a watery discharge from the eyes and nose. These symptoms may be mistaken for a cold.

Within a few days, the eye and nasal discharge becomes thick, yellow, and sticky. The dog develops a pronounced dry cough. Pus blisters may appear on the abdomen. Vomiting and diarrhea are frequent and may cause severe dehydration.

During the next one to two weeks, very often the dog seems to be getting better but then relapses. This often coincides with the end of the course of antibiotics and the development of gastrointestinal and respiratory complications due to secondary bacterial invasion.

Second stage occurs two to three weeks after the onset of the disease. Many dogs develop signs of brain involvement (encephalitis), characterized by brief attacks of slobbering, head shaking, and chewing movements of the jaws (as if the dog were chewing gum). Epileptic-like seizures may occur, in which the dog runs in circles, falls over, and kicks all four feet wildly. After the convulsive episode the dog appears to be confused, shies away from his owner, wanders about aimlessly, and appears to be blind.

In cases with brain involvement in which the diagnosis is uncertain, a spinal tap and analysis of cerebrospinal fluid may be of assistance. But this is not always diagnostic. Another indication of brain involvement is distemper myoclonus, a condition characterized by rhythmic contractions of muscle groups at up to 60 contractions per minute. The jerking can affect all parts of the body, but is most common in the head. Myoclonus is first seen when the dog is resting or sleeping. Later it occurs both day and night. Pain accompanies myoclonus, and the dog whines and cries. If the dog recovers, the jerking continues indefinitely-but becomes less severe with time.

Hard-pad is a form of distemper in which the virus attacks the skin of the feet and nose, producing thick, horny skin on the nose and calluslike pads on the feet. It first appears about 15 days after the onset of the infection. At one time, hard-pad and encephalitis were thought to be separate diseases, but they are now recognized as being caused by different strains of the distemper virus. Hard-pad is much less common than it was in the past, due to better vaccines and increased use of vaccines.

Treatment: Distemper must be treated by a veterinarian. Antibiotics are used to prevent secondary bacterial infections, even though they have no effect on the distemper virus. Supportive treatment includes intravenous fluids to correct dehydration, medications to prevent vomiting and diarrhea, and anticonvulsants and sedatives to control seizures.

The outcome depends on how quickly you seek professional help, the virulence of the distemper strain, the age of the dog, whether he has been vaccinated, and his ability to mount a rapid and effective immune response to the virus.

Prevention: Vaccination against canine distemper is almost 100 percent protective. All puppies should be vaccinated by 8 weeks of age. Brood bitches should be given a DHPP (distemper, hepatitis, parvovirus, and parainfluenza combination) booster shot two to four weeks before breeding. This ensures that high antibody levels will be present in the colostrum. However, some veterinarians believe this additional vaccine booster is not needed.

Reference

http://pets.webmd.com/dogs/distemper-symptoms-treatments-dogs