Diseases #32
Tapeworms are a common intestinal parasite seen in dogs and cats. Tapeworms are caused by Dipylidium caninum in the dog and cat. Cats can also get infected by another genus of tapeworm known as Taenia sp.
Tapeworms are transmitted to dogs and cats by fleas. The flea initiates an itch and the animal licks at its coat and swallows the flea. The tapeworm larvae, residing in the flea, is now able to develop into an adult worm in the intestinal tract. Cats also develop tapeworms by catching and killing rodents such as squirrels, mice and chipmunks. Once ingested, the larvae turns into a 6 inch long adult worm. It has a head that looks like the head of a Norelco® shaver! These heads attach to the lining of the intestine to get nourishment. The rest of the worm is composed of segments known as proglottids. The farther down the chain, the more mature they become. These are the segments that are commonly seen in the stool or around the perineal region of the animal.
Many owners do not notice any clinical signs in dogs or cats; just the tapeworm segments in the stool or perineal areas. In sufficient numbers there may a mechanical irritation of the worm that causes a mass expulsion of the worms. Animals can have diarrhea and poor coat condition.
Tapeworm segments can be found anywhere in the home. They look like grains of rice and when dried up, have a yellow tint to them. They may be found in animal bedding and areas that the dog or cat enjoys hanging out in. What really infuriates owners is when segments are found on their own bed pillows and linens. They freak out and want immediate treatment. I really can't blame them!
There are no lab procedures needed to be performed.
Diagnosis is made by finding the tapeworm segments on the animal. If segments are found around the home and there are multiple pets in the household, in time the animal with the tapeworms will be discovered with the typical white segment stuck to its body. Once in a while, a tapeworm egg sack is seen on a fecal flotation.
The treatment of choice for tapeworms is prazaquantel (Droncit®). One dose is usually sufficient but some individuals will repeat the dosage in several weeks to a month.
Treatment will not prevent future infections. You can not stop a cat from hunting. I usually treated outdoor cats every season of the year. This insured that the animal was tapeworm free for the majority of the year.
The prognosis for tapeworms is excellent. There are excellent treatment regimens available. Do not waste your time with over the counter products. They do not work.
The key for dog and cat tapeworm prevention is flea control. Make sure all pets are on a suitable oral or topical flea preparation and the environment is free from fleas by using sprays and or foggers to control flea populations. Clean up all stools found in the yard.
Dog and Cat tapeworms can not be transmitted to humans. Swallowing a tapeworm segment will not produce the infection since an intermediate host is required for transmission: fleas or rodents.
Tear Duct Obstruction is caused by the blockage or outflow of tears from the nasolacrimal duct to the nose or back of the throat.
Tears are produced in special glands in the eye. They serve the function of lubricating the front of the eye and contain products that naturally prevent infections. Tears will also be produced in excess to wash away particles of dust or other irritants that get in the eye. Any condition that causes excess tear accumulation is known as epiphora. It is a clinical sign, not a disease. Epiphora can be seen in tiny, white breeds of dogs like Maltese or Poodles.
In normal animals, tears flow across the cornea and accumulate at the medial canthus; the angle of the eye closest to the nose. They than pass through the nasolacrimal duct and empty into the throat or nose. Obstruction causes a buildup of tears and the associated clinical signs.
Clinical signs associated with tear duct obstruction are: excess accumulation of tears in the eyes, squinting in the affected eye, a rust colored staining of the skin below the lower eyelid and a often a foul odor in the region due to a bacterial or yeast infection in the area.
Lab tests must first be performed to rule out the more common causes of epiphora such as: corneal ulcers, conjunctivitis, foreign bodies, trauma, glaucoma and allergies. Once those causes have been ruled out, an obstruction can be looked into. The easiest way is to use a flourescein strip. It is moistened and applied to the eye. The animal is held still. In a few minutes in most dogs, a green discharge will appear from the nostril which indicates that the nasolacrimal duct is functioning. In obstructed ducts, the green color will not appear.
Diagnosis is made by ruling out other causes of epiphora. A negative response to a fluorescein strip test is suggestive of tear duct obstruction.
The treatment for tear duct obstruction is flushing the affected duct with a nasolacrimal canula. It is an indispensable tool to have around. The duct opening (puncta) is flushed with saline solution and the fluorescein strip is repeated. Some animals may have to have the procedure repeated. In some animals the duct opening never opened fully. Those cases can be surgically corrected by eye specialists.
Infections may be treated with appropriate antibiotic ointments. There are numerous products on the market that claim to remove tear stains from a dogs eye area. Some swear on one or the other. Clients have had off and on success with Angel Eyes®.
The prognosis for nasolacrimal duct obstruction is good; once it is assured that the duct opening remains open, either by frequent flushing or surgery. If a cause can not be found, many dogs need periodic flushing of the ducts to prevent epiphora and the discomforts related to it.
Torn Dewclaws are commonly seen in most medical practices. They are caused most frequently by getting caught in carpets or other braided material that catches the hook of the dewclaw. Animals panic and the tear occurs.
Dewclaws in dogs or cats are akin to the human thumb. As an animal stands, the dewclaw is the digit that is the highest on the inner side of the limb. Dogs and cats are always born with dewclaws on the front limbs. Some will have one or both or none on the hindlimbs.
Dogs normally wear down their nails by walking on hard surfaces such as sidewalks or asphalt streets. The dewclaw never touches the ground so it continues to grow. It will curl around forming a hook or form an ingrown nail. It is this hook that catches the stationary rug. Cats may be polydactyl, a word that means mitten paw or multiple nails on one digit. They can have multiple hooks that can get caught.
Beneath the nail bed tissue resides an artery. When the nail bed is sheared off, the artery is often torn along with it. Arterial blood pulses out. Owners notice bleeding coming from somewhere on the animals paw. Many people can not figure it out because the dog is in pain and the limb can not be examined. Many owners think that the pet has stepped on a sharp object causing a laceration.
No blood work is required unless there has been loss of blood. A CBC is than needed to check the hematocrit.
Diagnosis is by visualizing the torn dewclaw and associated arterial bleeding.
The initial treatment begins at home. Several people will be needed but the goal is to put some type of wrap on the pets lower limb. This may be a gym sock wrapped over the paw, elastic wrap or an old ace bandage. Anything that can apply slight pressure to the wound. Do not apply a tourniquet, unless instructed by your veterinarian. Take the animal to the hospital.
Under a sedative, the artery is closed off, the wound is debribed and the nail is excised. The whole procedure produces a one inch skin line that needs to be sutured and wrapped. Dogs and cats are put on antibiotics and sutures are removed in two weeks. The animal should be confined as much as possible.
The prognosis for dewclaw repair due to arterial laceration is excellent. The key is prevention. Dogs with dewclaws should have those nails clipped short so as to not get caught on rugs and the like. Owners often wish to have them surgically excised to prevent the problem from reoccurring. This is a very common procedure. When taking care of newborn puppies and kittens, I have always recommended that they be removed at 2 days of age. That way, dewclaw problems are never an issue as the animal grows up.
Toxoplasmosis is a world wide disease problem that can cause disease in any mammal. This is caused by the coccidial parasite known as Toxoplasma gondii.
Toxoplasma gondii exists in a cystic form embedded in the musculature of live rodents such as mice or squirrels. Once eaten, the cyst grows to maturity in the cat and the oocysts (eggs) are passed in the cats feces. Without the cat, the life cycle can not finish. If humans come into contact with cat feces containing toxoplasma eggs, they will get toxoplasmosis. The parasite will migrate to the muscle and nervous system. Women with toxoplasmosis will also pass the disease to their unborn children. This usually results in varying degrees of chorioretinopathies.
The dangerous part about the oocyst (egg) is that they are survivors! They can live in the environment for months without desiccating or being destroyed by excess heat or cold. Those eggs have to be in the environment for about 3 days after passing to become infectious to a passing host; be it another rodent or a human.
The USDA (United States Department of Agriculture) has veterinarians that protect our food supply from parasites and diseases such as Toxoplasmosis. In undeveloped countries, Toxoplasmosis may also be transmitted to people by eating contaminated undercooked or raw meat.
In small animals the disease is clinically seen more frequently in cats than dogs. Many cats are asymptomatic and are only involved in the life cycle completion of the parasite. Cats that do get sick have initial signs seen in many diseases: anorexia, lethargy and depression. As the disease progresses signs of jaundice (liver disease), vomiting and diarrhea plus seizures can be seen. Most cats that are healthy often do not show clinical signs. Cats that are immunosuppressed from diseases such as FIV (Feline Immunodeficiency Virus) or FeLV (Feline Leukemia) are at a higher risk of developing signs of the disease.
The most frequently performed tests are immunological or DNA related. Identifying the levels of toxoplasma antigen and the level of antibodies is almost always done. If there is infectious material present, the PCR (Polymerase Chain Reaction) test is very good at identifying the agent. In severe cases, lung fluid can be used to identify the organism.
Diagnosis is made by the presence of the organism by using the PCR test plus the many serological tests that can tell if the infection is acute, chronic or a relapse.
Once in a blue moon, diagnosis can be made by finding the oocyst in the cats feces. This is not reliable since a cat will only pass infected toxoplasmosis oocysts for about 5 days. There are also other common coccidia (Eimeria sp and Isospora sp) that look just like the Toxoplasma gondii oocyst (egg).
The most commonly used prescription drug to treat toxoplasmosis in cats is clindamycin. Other supportive measures such as fluids and other care are provided; particularly if other organs such as the liver, lung and nervous system are affected.
Cats with a straight, uncomplicated case of toxoplasmosis can recover if treated early with clindamycin and other support therapies. Cats that are young or showing multiple organ involvement have a very guarded prognosis. Cats that are immuno-suppressed have a poor prognosis.
As like most things in medicine, prevention is the way to go!
1. If pregnant, do not clean the litter box. Have someone else in the household empty the litter box daily.
2. Do not consume raw meat. Properly wash and clean all foods.
3. Wear gloves when gardening. Cats will defecate anywhere and that includes your garden soil.
4. If you have a sandbox in the back yard for children, make sure it is covered when not in use.
5. Ideally, keep all cats indoors. Without a cat crossing paths with a mouse or other rodent, the life cycle can not complete and hence there wouldn't be any human disease.
6. Dogs love getting into litter boxes and eating the contents. Elevate litter boxes up on an old table or facsimile to keep dogs from getting to the box.
The fact is, is that cats always get blamed for everything when the word "Toxoplasmosis" come up. In fact, more people get Toxoplasmosis in the United States much more frequently from handling contaminated meat.
Can a cat be checked for Toxoplasmosis? Yes they can be but the results are a twisted irony. If a cat tests positive on antibody titers, it just means that the cat had the infection in the past and has developed antibodies to the disease. This animal is probably immune for life and would not be a concern in any household. The irony is, is that most cats will test negative. That means they have never been exposed to the parasite BUT COULD BE IN THE FUTURE. For that reason, you have to be more concerned about the negative titer cats much more so than cats with an antibody titer.
Transmissible Venereal Tumor is a disease transmitted during copulation. It is seen in both the male and female. The cause of the tumor is unknown.
As with any venereal disease, this tumor can be found on both sexes. It is most commonly seen in young, unaltered dogs. It is not transmissible to humans.
The most common finding is a deep red lobular growth seen on the penis of the male and the vulvar area of the female. They may spontaneously clear but they are quite friable and can bleed a lot if the are picked at or licked at by the animal..
Stain smears of the lesions may be looked at under the microscope but the most important lab test is a biopsy that is sent to the pathologist for diagnosis.
The presence of a lobulated red growth on the genital organs of either sex is enough for a tentative diagnosis of TVD. Histopathology will provide a concrete diagnosis of the condition.
Treatment of TVD is complete excision of the mass; which is than sent for pathology.
If the tumor is benign and it is removed, the prognosis is very good. If the tumor is malignant, the prognosis is much more guarded due to the chance of metastasis to other organs.
Some of these tumors spontaneously disappear. Specific antibodies to the tumor are made inducing it to shrink and disappear. In the mean time owners have to keep the pet from licking at their genitals. An E- collar is very effective to stop that behavior.