Pathophysiology

Infection with Blastomyces occurs when a cat or dog inhales the fungal spores into the lungs. The incubation period is from 5 to 12 weeks. Some animals don’t show clinical signs for a long time after being infected, but those animals are not contagious to other animals and people. Blastomycosis organisms have a predilection for the respiratory tract, and pulmonary disease is the most common sign (88-94% of canine cases). Once the lung disease develops, yeast forms of the organism spread throughout the body. Organs typically affected include eyes, bones, skin, lymph nodes, subcutaneous tissues, brain, and testes. It can also be found in the nose, prostate, liver, mammary glands, and heart, but those locations are less common.

Dogs appear to be much more susceptible to infection than other species. Although the disease does occur in both people and cats, the incidence is much lower than in dogs. Dogs are ten times more likely to contract the disease than are people, and 100 times more likely than are cats. The incubation period in dogs is also shorter than in people. The reason dogs are more susceptible is unknown, but immune-deficiency may play a role. Annual prevalence in dogs in endemic areas is estimated at 1-2%. Many infected animals live within 0.25 mile of water. An increased number of cases can occur after periods of unusually heavy rainfall. Historically, young (i.e. 1-5 years), male, large-breed (e.g. hounds, pointers) dogs have had the highest risk of infection. (This is probably because these animals would tend to have more contact, due to hunting activities, with the organism’s geographical area.) However, any age, breed, or sex of dog can be infected.

Clinical Signs

The signs of illness will depend on what organs are infected. Some dogs will have eye problems, and some will have neurological signs (seizures, head tilt, etc.). Lameness may occur, if the infection is in the bones. Owners of dogs in the specific geographic areas should watch for coughing, difficulty breathing, eye inflammation, enlarged testicles, fever, swollen lymph nodes, ulcerated/draining skin lesions, bloody urine, difficulty urinating, nasal cavity signs (including bloody nasal discharge), and lack of appetite. (Weight loss occurs because of the decreased appetite.) Infections in the nasal passages may result in skull damage, and lead to infection of the brain. Large skin abscesses and neurologic signs are more common in cats than in dogs, while bone lesions are more common in dogs than in cats. Hypercalcemia can occur in dogs, although it’s rare in cats and non-domestic feline species.

Diagnosis

Diagnosis involves physical exam, blood tests, imaging (radiography, ultrasonography, CT, etc.), urinalysis to look for Blastomyces yeast, cultures, serology, and biopsies of affected organs. Fungal serology, to look for antibodies, is not always accurate and has been known to produce false negatives. The enzyme immunoassay (EIA) for B. dermatitidis galactomannan antigen appears to have a high sensitivity in urine (93.5%) and serum (87%). The EIA assay is commercially available; cross reactions with Histoplasma capsulatum, Coccidioides immitis, and Penicillium marneffei can occur with this assay. The definitive diagnosis is finding the fungus in the tissues.

Treatment

Treatment involves various antifungal medications, including itraconazole, ketoconazole, fluconazole, amphotericin B, and some combination therapies. These medications usually need to be taken for a long period of time; how long depends on the specific case. Treatment usually can be done at home, unless the disease is severe. Pets with respiratory involvement should be on restricted activity. In severely ill dogs, intravenous fluids, oxygen, antibiotics for secondary infections, and pain medication may be necessary. Skin lesions may require wound cleaning and debridement.

Eyes that are severely affected may not respond well to the treatment because the medication does not penetrate eyes very well. Ocular blastomycosis cases may need systemic and topical corticosteroid therapy, topical anti-glaucoma medications, etc. Significantly affected eyes may require enucleation (removal of the eyeball).

Pets with severe lung disease may get worse at the beginning of treatment because the fungal organisms are dying; the mass death of organisms can cause severe respiratory problems.

Patients may not appear to improve for one to two weeks after the start of treatment. Close monitoring should be done for the first two weeks, and then rechecks are usually scheduled on a monthly basis. Rechecks may involve blood tests, biochemistry profiles, and imaging, if appropriate.

Prognosis

The prognosis for many pets is good, especially if owners can afford to treat the pet for long enough. Approximately 50% to 75% of affected dogs recover when treated with itraconazole, fluconazole, or an amphotericin-ketoconazole combination. Prognosis is poor for dogs with severely affected lungs, but if the dog survives the first 7 to 10 days of therapy, the prognosis improves. However, mortality rates in dogs with Blastomyces dermatitidis can be as high as 41%.

The prognosis for the retention of vision, in animals that have eye disease, is variable.

Dogs with brain involvement often die. Seizures are common upon death of the organism and may be uncontrollable.

Prognosis is also poor when at least 3 body systems are involved.

Relapses are most likely to occur in dogs that had a severe case at onset, or dogs that were not treated long enough. Relapses are most common within the first 6 months after treatment. Dogs that recover from the disease are probably not immune to getting it again.

After discontinuing therapy, animals may be rechecked at 1, 3, and 6 months for evidence of relapse. In one study, relapse rates for itraconazole and fluconazole were 18% and 22%, respectively. Relapses are treated like a new infection.

There is no way to prevent your pets’ exposure to Blastomyces other than by keeping them away from affected geographic areas.

Zoonotic Potential

Blastomycosis is not considered to be a zoonotic disease. It is acquired by humans via inhalation or direct contact with infective conidia/spores. Risk of infection is higher for excavation workers, and for people working or playing in wooded areas with waterways. Blastomycosis cannot be spread between dogs and other animals, or between dogs and people. However, immunocompromised people should limit their contact with infected pets and should wear gloves when cleaning and treating draining lesions.

The Human Disease

Infection with Bartonella henselae in an immunocompetent person (i.e., a normal, healthy person) person leads to cat scratch disease. The inoculation site, a scratch from a claw containing bits of flea dirt, develops a small red bump called a papule. About 2 to 3 weeks following contact with the infected cat, the lymph node in the area will swell and become painful, and a fever will develop. These signs generally resolve on their own, and the condition is minor, though lymph node enlargement can persist for several months.

If the patient does not have a competent immune system (in other words, they are very old, very young, debilitated from another condition, etc.), one of several far more serious syndromes can result. The infection goes deeper into the body and causes spleen enlargement, and potentially encephalitis, heart valve infection, and other conditions. These syndromes are rare, but they are potentially quite serious.

How Likely Is It for a Cat To Be Infected?

Since fleas carry the bacteria, cats with insufficient flea control are at the highest risk. This means cats living in climates that are warm and humid (conditions where fleas thrive best) are most likely to be infected. If conditions are right, up to 40% of cats in an area may be infected. If a person is diagnosed with cat scratch disease, there is a 90% chance that the cats they own will be found infected as well.

This sounds somewhat concerning for the cat-owners in a flea area but it is important to realize that an infected cat cannot transmit the infection without a claw full of flea dirt. If the fleas are removed from the infected cat, there will be no flea dirt in the coat and no risk of disease transmission. Experimental studies have not been able to demonstrate cat-to-cat transmission in cats that mutually groom each other, fight with each other, mate with each other, or share food or litter with each other, nor has transmission been demonstrated between infected mother cats and their kittens. Short of an actual blood transfusion from an infected cat, fleas or ticks are needed to spread the infection.

Do Infected Cats Get Sick?

This is a highly controversial question. It was only relatively recently discovered (1992) that cats themselves were more than simple carriers of Bartonella henselae and that they could actually become actively infected themselves.

Several illnesses seem to have been associated with Bartonella infection (fever, deep eye inflammation, lymph node enlargement, muscle pain, reproductive failure, and bacterial heart valve deposits called endocarditis), but these seem to be isolated cases for the most part. The Bartonella organisms are highly adapted to live in the feline body without causing disease, and it is only in rare situations that cats actually experience issues from this infection.

It has been suggested that Bartonella infection may be at the root of numerous chronic inflammatory conditions of the cat. With such high numbers of infected cats occurring regionally (up to 40%), it is going to be difficult to prove one way or the other whether there is a real association or just coincidence.

Can Dogs Get Infected?

The short answer is yes, though the species they get is Bartonella vinsonii rather than Bartonella henslae. Fleas may carry the infection as they do for cats, plus it appears that ticks may also be carriers. Since there are numerous infectious agents spread by ticks and it is not unusual for a dog to have multiple tick-borne infections, it is difficult to determine which infection is causing which signs.

Is My Cat Infected?

Testing is not recommended for the average cat, even if the cat is sick. Testing would be a good idea for any cat that may become a blood donor, for the rare sick cat where Bartonella-related disease is actually being considered if a human in the home has been diagnosed with a Bartonella-related disease, or if there is an immune-compromised person in the home, in which case testing is actually important.

There are five tests available to detect Bartonella henselae: ELISA, IFA, PCR, Culture, and Western Blot. All the tests have pros and cons, and no method seems to shine above the others.

The ELISA, IFA, and Western Blot tests are tests for antibody detection, the idea being that if antibodies against Bartonella are there, then Bartonella must be there as well. For most diseases where antibody levels are used to establish a diagnosis, a minimum titer or antibody amount is considered necessary to say “Yes, this patient is infected.”  A problem with this is that we know that up to 11 percent of cats with Bartonella organisms happily circulating in their bloodstreams will not make antibodies and will thus test negative. At least this means that when the test is negative, there is an 89 percent or greater chance that the cat is truly negative. For screening, this kind of antibody testing is frequently paired with PCR testing.

PCR is a very sensitive DNA test for Bartonella, but because the organism only intermittently circulates, false negatives can result if not very much Bartonella DNA is circulating. Results from PCR testing can rapidly distinguish different species of Bartonella. 

The most reliable test is the blood culture; however, several consecutive cultures are needed because the organism tends to circulate only intermittently. A positive culture is proof of infection, though a negative culture may simply not have been taken at the time when the organism is circulating. 

In humans, a delayed hypersensitivity skin test is used as part of the diagnostic criteria for cat scratch disease but this test has not been useful in cats. In this test, similar to the tuberculosis test most of us are familiar with, a scratch on the skin is made, and a reaction to the introduced antigens may occur either right away or in approximately 48 hours (delayed hypersensitivity reaction). Cats are poor delayed hypersensitivity responders. 

All in all, it is hard to rule out a cat as a carrier of a Bartonella organism. If the results of testing are suggestive of infection, treatment can be considered if the cat is truly believed to have an illness from the infection or if there is realistic concern about exposure to an immune-compromised person.

Treatment for Cats

An assortment of antibiotics have been used against Bartonella henselae in cats: clavulanic acid-amoxicillin combination, azithromycin, doxycycline, and quinolone class medications (enrofloxacin, marbofloxacin, etc). Efficacy has been mixed, and Bartonella henselae rapidly becomes resistant to therapy. Treatment is currently recommended for cats showing symptoms of disease or for cats living with immune-compromised individuals.  Treatment lasts a minimum of three weeks.

Preventing Human Infection of Bartonella: Guidelines from the Centers for Disease Control and Prevention

• Cats belonging to immune-compromised people should be kept indoors only and should not have contact with cats that go outdoors.
• Claws should be kept trimmed.
• Cat scratches should be promptly washed. (This goes for everyone, not just immune-compromised people.)
• Flea control should be strict. 

Preventing Disease

No data support chemoprophylaxis (i.e., preventive drug treatment) for Bartonella-associated disease. In simpler terms, if a suspicious cat scratch has occurred, there is no point in using medication to prevent infection.

 The same is true with many other substances, like water, that need to be regulated. Urine is (usually) sterile, so unless there is a urinary tract infection, urine is pure. It’s not the terrible stuff that many third graders make it out to be. True, it does have the waste products of metabolism in it, which a body needs to remove.

And that’s where some of the problems begin. If the flow of urine stops, those waste products build up and negatively impact the way the body works. One of the most common ways that happens is when a cat’s urethra (the tube that carries urine from the bladder to the litter box) gets blocked. Known in veterinary parlance as a ‘blocked cat’ or ‘blocked tom,’ this poorly understood disorder is seen with alarming frequency in veterinary hospitals and ERs.

Many ERs see about two to three cats per week who cannot urinate. Cats can be in all stages of the disease, from the early onset ones who just seem a little painful and have a big, hard bladder to the nearly dead ones that are in many cases beyond saving.

The actual plug that stops the flow can be made of bladder stones (often erroneously called kidney stones), tumors or a gooey mix of mucus and protein known as ‘matrix’ that has the consistency of toothpaste. How and why matrix forms, no one knows, despite a few decades of investigation. Adding to the confusion, the name of the disorder has changed no less than four times in the past 20 years from feline lower urinary tract disorder (FLUTD) to feline urologic disorder (FUS) to feline interstitial cystitis (FIC) to the most recent iteration of Pandora Syndrome, which hasn’t really caught on yet.

The causes go beyond a mucousy plug, as well. A host of other factors, such as stress, lack of access to water, diet, infectious agents, indoor lifestyle, and many other causes have been implicated as being responsible for the lead-up to getting blocked. Those little plugs don’t form in a vacuum: something causes them to form, and we don’t know with any certainty what factors contribute to it.

Cats that are blocked often show the following signs:

1. Straining repeatedly in the litter box (often mistaken for constipation)
2. Crying or howling
3. Licking at the genitals/below the base of the tail
4. Hiding

If you notice your cat showing any of the above signs, get right in to see your veterinarian or go to your nearest ER as soon as possible. Don’t delay as a few hours can make a big difference. The longer those toxins circulate unchecked, the more pain the cat experiences, the more work the veterinarian has to do, and the bigger the final bill will be.

In advanced cases, where the urine flow has been stopped for more than 24 hours, cats can become systemically ill from retained toxins and start vomiting, or become very weak and lethargic. Death usually happens within 48 hours, and it’s not a pleasant way to go. The pain with this disease is immense, and some cat owners understandably choose euthanasia over trying to reestablish the flow of urine.

The course after unblocking these cats is just as unpredictable and mysterious as the factors leading up to the obstruction; some cats are released from the hospital never to suffer another episode, while others will have repeated occurrences days, weeks or years later. This is an inhumane disease.

Managing these cases medically can go way beyond relieving the obstruction in some cases. First priority is fixing the plumbing problem: getting urine to flow. This is usually done with anesthesia and a catheter to remove the obstruction. Managing the havoc wreaked by the toxins is next. This can necessitate some medical dancing as veterinarians try to put things back in place. Disorders of deadly potassium, elevated renal values, and severe dehydration can mean days in the hospital, even long after the urine is flowing again. It can get complex, expensive, and can wear down even the most committed of owners for the really medically complex (and expensive) ones.

However, getting the urine to flow and taking the cat home is the easy part. After this episode, lifestyle changes are necessary: medication tweaks, medical rechecks, and diet changes that try to extend the initial complexity of this disease across months or years.

Compared to 20 years ago, cats with this disease do go home and get better, even some of the tough cases.  Someday, science will provide an answer and veterinarians will have some means to prevent this disease in the first place, or some surefire way to treat it. Until then, rush your cat in to be seen if you see the signs.

Conjunctivitis is inflammation of the conjunctiva, a tissue that makes up part of the eye and eyelid. In people, the conjunctiva is the white part. Conjunctivitis is common in cats and can be a result of infection or injury.

The two bacteria species best known to cause conjunctivitis in cats are Chlamydia felis and Mycoplasma spp.

An infection caused by Chlamydia may cause redness, discharge, and excessive tears. Bacterial conjunctivitis caused by Chlamydia is treated with antibiotics. All cats in a household may need to be treated, as some cats who have it do not show any symptoms.

Mycoplasma is a natural inhabitant of every cat’s eye, so infection happens when there is an overgrowth of that bacteria. Treatment for the Mycoplasma infection is similar to that of Chlamydia: antibiotics. The goal in treating Mycoplasma conjunctivitis is to reduce the overgrown number of bacteria back down to a normal level because it is impossible to eliminate them entirely.

Who gets bacterial conjunctivitis?

Both cats and dogs can get conjunctivitis caused by bacteria or viruses. Conjunctivitis is the most common cat eye disease, and most cats will develop the infection once in their life. All breeds can develop infection, and juvenile and young adults are more likely to get it.

Clinical Signs of Either Form

1. Red eyes
2. Eyelid redness
3. Eyelid swelling
4. Excessive blinking
5. Eye discharge
6. Eye crusting
7. Tearing
8. Squinting
9. Scratching the face to relieve irritation

 Diagnosis

A physical exam of the eye by your veterinarian is the first step, as this will rule out other causes of redness, such as trauma.  The easiest diagnosis is a cytology test, which means looking at scrapings of the irritated tissue under a microscope. If a lot of bacterial and inflammatory cells are seen, it is likely that the eye is infected. Checking scrapings is a quick test for infection that can be done at the clinic during your appointment. PCR is another test that can be used to detect the specific organism causing the infection, but typically needs to be sent out to a lab.

Treatment

Antibiotics are used to treat bacterial conjunctivitis, mainly doxycycline.  Mycoplasma and Chlamydia are the most common bacteria involved in eye infections, and doxycycline is effective against both.

Prognosis

Treatment should clear the signs and infection. However, if the eye still looks infected or just doesn’t look normal, contact your veterinarian. The ongoing bacterial infection may also be caused by an unknown factor that needs to be treated before the eye infection can be cured.

Prevention

There is a vaccine for Chlamydophila felis, but it is not required and is usually only suggested if your cat is at a higher risk for an infection or in a multi-cat household. There is no vaccine for a Mycoplasma spp. infection because it is normally in the eye anyway.

The key to preventing infection is separating sick cats away from the unaffected ones and bringing them to your veterinarian at the first sign of infection.

Common areas for bite wound abscesses include the facial cheeks, the legs, and the base of the tail. These are the areas where fighting cats tend to bite one another.

This patient’s bite wound abscess (the small red puncture wound on its hip) would not be visible without shaving the fur away from the area. Photo by MarVistaVet

Treatment

• If the abscess has not ruptured, it will need to be lanced. Once the abscess is open, it will need to be flushed clean of infected debris. If the abscess is large or especially painful, sedation may be required to accomplish this.

• Older abscesses may have enough devitalized overlying tissue to require surgical trimming and stitches. Some abscesses are large enough to require an indwelling rubber drain to assist with removal of the pus. You may have to flush the drain with disinfectant at home.
  
• The cat will likely need antibiotics at home. If so, you will need to give either pills or liquid medication (tell your veterinarian if you have a preference). Alternatively, there is an injectable antibiotic (Convenia®) that lasts two weeks that may be given in the clinic, eliminating the need for oral medication at home. Your veterinarian will likely recommend one of these treatments in addition to cleaning and flushing out the wound.

Warm compresses are helpful for the first few days following discharge. The heat helps liquefy diseased tissues so that they can drain. To hot pack the area, use a warm (not hot) washcloth applied to the wound for 5 to 10 minutes once or twice a day as directed by your pet’s doctor.

Other Important Things

Feline leukemia (FeLV) and feline immunodeficiency (FIV) viruses represent serious contagious infections spread by bite wounds. The American Association of Feline Practitioners has guidelines for viral testing. Testing, accomplished by a simple kit that can be done in your veterinarian’s office, ideally should be done 60 days or more from the time of the bite. Outdoor cats should be tested annually for these viruses regardless of vaccination status. We recommend testing at the time of the abscess treatment if a test has not been performed in the last year. This test will not rule out any infection initiated by this bite but will test for any infection from past bites. A positive test could alter your cat’s ability to heal. Additionally, positive cats should best become indoor cats to minimize exposure to hazards and reduce transmission of their disease to other cats.

If your cat has not been vaccinated for rabies, it is especially important to make sure this vaccine is current. Rabies is transmitted by bite wounds and since there is no effective treatment for either animals or humans, it is important to consider this simple prevention.

More simply, this means the airways of the lungs are inflamed, plus they are extra reactive to mental stress or respiratory irritants, and the flow of air through the lungs is reduced (either sometimes or all the time). When all three features are present, we can be comfortable diagnosing asthma.

What Exactly is Happening in the Lungs with Asthma? 

First, excess mucus forms in the airways. After that, the airway walls swell with inflammation and can actually ulcerate. Finally, the airway muscles go into spasms leading to constriction. Airway constriction leads to an inability to draw a deep breath, intolerance to exercise, coughing, and musical sighing sounds called “wheezes,” though not all these symptoms may be apparent at the same time.

Is Feline Asthma the Same as Human Asthma?

The feline condition was named asthma because of the clinical features shared with the human disease. As of this time, it appears that all the diagnostic criteria needed to diagnose asthma in people are shared by cats, yet we are still working out the mechanics of this syndrome in cats and have a great deal to learn. For example, in humans, we know that while actual symptoms of asthma occur in episodes, the airways of the lung are diseased all the time. We do not know yet if feline airways are also diseased all the time or if the actual airway structural changes occur only when there are clinical signs of distress.

How is the Diagnosis Made?

Because of the constricted airways, the actual volume of air this patient can move in and out of the lungs with each breath is reduced. There is often a great deal of effort seen in the cat’s breathing. The abdomen appears to be working to push air out and the breaths are shallow and rapid. The cat may even be breathing with its mouth open in an effort to move the largest possible amount of air.

The next step toward making a diagnosis of feline asthma is the chest radiograph, assuming the cat is not in too much distress to hold still for this procedure. Classically, this radiograph will show what is called air-trapping, meaning that the small airways have constricted so that inhaled air cannot be exhaled. The lungs are larger in appearance than normal as they are over-inflated. The diaphragm may seem flattened due to this over-inflation.

It is possible to view the tiny airways in much higher detail on radiographs. This is partly because they are made more prominent because of the mucus and inflammatory fluid inside them (the doughnuts and tramlines, as mentioned below) and partly because they are surrounded by more air than usual (air-trapping).

Inflammation and mucus build up within the airways, causing their walls to appear thickened in the radiograph. The terms used for such airway appearance are doughnuts (when viewing the airway end-on) or tramlines (when viewing the airway from the side). You may hear your veterinarian use these terms, and they are classical findings in airway disease. 

Some Asthmatic Cats Have Normal Radiographs

Since visible changes are not always evident on radiographs, which can lead to diagnosing asthma when it is not there. Indeed, diagnosing asthma can be complicated, and it is famously underdiagnosed because up to 23% of asthmatic cats can have completely normal radiographs.

The coughing cat with normal chest radiographs poses a diagnostic dilemma. It is hard enough to sort out potential issues when there actually are radiographic changes, as many conditions can mimic others. Because of the nature of feline heart disease, where the heart muscle can thicken without the overall external shape of the heart changing, heart disease should be considered. In heartworm-endemic areas, feline heartworm disease should be considered. If the patient is thought not to have too high of an anesthetic risk, a tracheal wash and/or bronchoscopy can be considered but often have indefinite results. CT (cat scan) imaging is emerging as a helpful diagnostic tool, but it is not yet available in many areas.

Response to Therapy as a Diagnostic Test

One important asthma feature is that the airway constriction it engenders is reversible. In an emergency situation, a small dose of epinephrine (adrenalin) or terbutaline (which expands airways) can reverse an asthmatic crisis in as little as 15 minutes. Response to an injectable corticosteroid (such as dexamethasone) generally yields a positive response within 30 minutes.

Sometimes, diagnostic tests still leave room for questions, and you have to simply go with medical treatment for asthma and regard response to therapy as evidence that the diagnosis is correct. See below for a list of medications commonly used in the long-term management of this problem.

Treatment Options

Oral and Injectable Steroids 

It is crucial to realize that the underlying problem in the airway is inflammation. Inflammation is what is responsible for constriction. To resolve inflammation, corticosteroid medications have been the cornerstone of therapy. These can be given in pills, by injection, or, more recently, through a metered dose inhaler. Usually, treatment is started with either an oral corticosteroid such as prednisolone or a long-acting injection such as Depo-Medrol. These medications are relatively inexpensive, and a good response to them helps confirm the diagnosis, as mentioned. A better strategy might be to use oral or injectable steroids to ensure that they work and if they do, change to a metered dose inhaler (see below), as there is much less potential for corticosteroid side effects with an inhaler.

If the response to oral corticosteroids is good, they may be continued long-term, supplemented with some of the other medications mentioned below, or used only during flare-ups. Long-term corticosteroid use has some potential for side effects, though feline patients tend to be resistant to these problems. If giving pills is too difficult, especially in a cat that is stressed and having some trouble breathing, a long-acting corticosteroid injection can be used periodically to control asthma symptoms. Cats are more sensitive to potential side effects from these injections as they are much stronger than oral corticosteroids. This sensitivity means that injections can only be given periodically without the risk of developing diabetes mellitus. If the cat seems to require an injection more frequently than every other month, a metered dose inhaler should be considered (see below for details).

When using oral corticosteroids, it is important to taper the dose over time so as to find the minimum dose needed to control symptoms. If higher doses are used indefinitely, asthma symptoms may become resistant to steroids. This resistance is more of a problem with injectable steroids and manifests as a shorter and shorter interval between the need for the injection. Again, if this is seen, consider changing to an inhaled form of medication.

Metered Dose Inhalers

Human asthmatics have enjoyed the benefits of portable inhalers for years. These handy devices deliver medication locally to the airways, thus minimizing drug side effects to the rest of the body while maximizing desired response.

There were two problems with using these devices in cats:

• Cats cannot be told when to inhale. 
• Cats tend to object strongly to the spray puff delivered by the device.

The discovery that the pediatric spacer could also be used for cats has solved the feline inhaler problem as well. The setup is the same as described above for young children and the cat takes 7 to 10 breaths from the face mask to be properly dosed.

Corticosteroid inhalers, Flovent® being the most popular, are typically used twice daily long term while airway dilator inhalers such as albuterol-containing Proventil® or Ventolin® are used for flare-ups.

Cats are generally started on a combination of oral prednisone and the metered dose inhaler and gradually maintained on only the metered dose inhaler.

Pediatric equipment is generally available from most human pharmacies, however, a device created specifically for feline use can be ordered. It comes with a spacer and an appropriately sized face mask. Your veterinarian will need to prescribe the metered dose inhaler usually from a regular human pharmacy.

See the Aerokat device.

Are there other Treatment Options?

Other medications that might be helpful include:

Allergen-Specific Immunotherapy 

Since allergy is generally a part of the asthma picture, it makes sense that “allergy shots” might be helpful. In fact, they are helpful to many cats. It is important to realize that this form of therapy takes months before benefits are obvious so it is not a method for fast relief but more for the “bigger picture.” The owner must be able to give injections to the patient at home regularly. A veterinary dermatologist is generally needed to oversee this type of therapy.

Airway Dilators

Terbutaline (Brethine®) and theophylline are airway dilators commonly used in the management of asthma. It makes sense that if constriction is an important feature of this disease that eliminating constriction would be therapeutically helpful. Terbutaline is available orally or as an injectable. Some veterinarians encourage owners to keep a bottle of injectable terbutaline at home in case of a crisis and show them how to give it. If you are interested in this, let your veterinarian know. Theophylline is an oral medication usually given once a day at bedtime.

Cyclosporine

The use of cyclosporine in asthma is relatively new. Cyclosporine is an immunomodulator often used in organ transplant patients. It has been used occasionally in cats where adequate suppression of inflammation has not been possible with combinations of the other medications listed or when the cat is unable to take corticosteroids for other reasons (concurrent diabetes mellitus, infection, history of calcium oxalate bladder stones, etc.). Cyclosporine should not be prohibitively expensive since cats, being small, require relatively small doses but blood levels of cyclosporine may be periodically recommended which increases the expense of this treatment significantly.

Don’t Forget…

Minimizing irritants in the air is always helpful to an asthmatic cat.

1. Do not allow cigarette smoke in the cat’s environment.
2. Use dustless cat litter.
3. Consider non-topical insecticides. No sprays, either.
4. Regularly replace air filters at home.

It is important to realize that asthma can culminate in a respiratory crisis that can become life-threatening if ignored. If your cat begins to breathe with an open mouth or if you see excessive abdominal movement during breathing and the cat is not purring, you may have an emergency situation. Contact your veterinarian immediately.

For more details, including a video on the use of the inhaled system, we recommend visiting Fritz the Brave, a website set up by one family devoted to their asthmatic cat. It has grown into a detailed instructional site for both pet owners and veterinarians interested in the details of inhalers for feline asthma treatment.

Arthritis, also known as osteoarthritis or degenerative joint disease (DJD), is a degenerative, progressive, and irreversible condition of the joints. It is characterized by the progressive loss of joint cartilage, bony spurs/growths, and the thickening and scarring of connective tissue around the joint, usually as a result of injury.

Approximately 25 percent of dogs are diagnosed with arthritis in their life time, and as many as 60 percent of dogs have radiographic evidence of it.

Degenerative joint disorders are probably as common in cats as in dogs but are less likely to be associated with obvious clinical signs, such as lameness. In one study, 90 percent of cats over 12 years of age had radiographic signs of osteoarthritis.

Arthritis is classified as primary or secondary. Primary arthritis is associated with aging, due to years of wear and tear on the joints. Secondary arthritis is the result of an external event or force (e.g., trauma, poor joint alignment, etc.) that once damaged the joint cartilage.

Arthritis can affect any age, sex, and breed of dog and cat. Most predispositions to it relate to underlying causes, such as elbow dysplasia, hip dysplasia, osteochondrosis, and so forth.

Diagnosis

Diagnosis is based on what is found in the physical examination, X-rays and other diagnostic imaging, joint taps, cytology, force plate gain analysis, therapeutic drug trials, and other tests.

Physical Examination Findings in Dogs

Lameness is the most common sign. It may happen once in a while (episodic) progressive (gets worse over time), or be persistent. Stiffness is common after periods of rest. Stiffness and lameness may decrease when the dog warms up a bit with some activity. Lameness often gets worse after periods of overexertion. Pain, swelling, and decreased range of motion may be seen. Thickened joints, excess fluid in the joint space, and muscle weakening are likely to occur.

Physical Examination Findings in Cats

As opposed to the visible lameness seen commonly in dogs, many cats simply become less active, may hide, or develop behavioral changes, such as irritability, decreased grooming, or difficulty getting into position in the litterbox. Cats also may have joint swelling/thickening, too much fluid in the joint space, and decreased range of motion. There may or may not be pain when the cat’s affected joint is moved by you or your veterinarian.

Diagnostic Imaging

Radiographs (X-rays) and CT scans may show the excess fluid in the joints; the bony spurs; signs of an underlying disorder, such as elbow dysplasia, osteochondritis dissecans, hip dysplasia, or cruciate ligament rupture; and so forth.

Kinetic Tests

Force plate gait analysis in dogs can help find where the lameness is within the joint. It can also show the severity of lameness, both before and after therapy. A force plate is mounted to the floor, and the dog walks over it. Measurements are taken to see which areas use the least force (more affected) and vice versa. The gait analysis hasn’t been used as often in cats.

Therapeutic Trial

In some cases, a therapeutic trial of nonsteroidal anti-inflammatory drugs (NSAIDs) may help confirm the diagnosis if the lameness is less noticeable after taking them.

Treatment, Management, and Prevention

It is not possible to cure arthritis.

The goals are to alleviate your pet’s discomfort, to minimize further degenerative changes to the joint, and to restore the joint’s functionality. Multiple types of treatment are usually necessary to relieve pain, stiffness, and discomfort.

Managing your pet’s weight is important. Excess weight increases stress on the joints and muscles. If your pet is obese, your veterinarian will want your pet to lose weight. Daily, low-impact activities, such as walking and swimming, will not only help your pet with losing some pounds but can also improve joint mobility, muscle mass, and exercise tolerance.

Joint supplements known as chondroprotective agents will help support the cartilage and will have some anti-inflammatory effects. These agents will slow the breakdown of cartilage and/or provide the building blocks that can help build it. Some agents also increase joint fluid secretion and thus decrease inflammation.

The main components of chondroprotective agents are polysulfated glycosaminoglycan (PSGAG), glucosamine, and chondroitin sulfate. Oftentimes there is no improvement using chondroprotective therapies. The failure may be due to too little cartilage left in the affected joint as there’s bone on bone; unresponsive joint inflammation; variable bioavailability of the drug between different products; and the lack of analgesia.

Although the injectable PSGAGs are more expensive, they provide a faster and longer-lasting response than the oral forms. If there is no response after 4-6 weeks, your veterinarian may discontinue use of PSGAGs.

Diets containing omega-3 fatty acids may help reduce inflammation. Some studies have found that dietary supplementation with fish oil omega-3 fatty acids can improve the clinical signs of arthritis in dogs, and may allow the NSAID dose to be reduced.

NSAIDS are an important component of arthritis therapy in dogs. Side effects that you should be aware of include stomach upset, elevated liver enzymes, and potential worsening of chronic kidney disease. Few NSAIDs are licensed for use in cats; your veterinarian will advise you about what NSAID options are available for your cat.

Analgesics such as tramadol, gabapentin, and amantadine may provide pain relief in dogs.

Alternative therapies such as acupuncture, stem cell therapy, platelet-rich or conditioned plasma, physical therapy, rehabilitation therapy (e.g. radial shock wave therapy, pulsed signal therapy), green-lipped mussel supplements, vitamin E, and zoledronic acid may be beneficial in some canine patients. Studies to support their use are still being done.

Surgery 

Your veterinarian may consider surgical options if your pet’s response to medical treatment is low. In addition, your veterinarian may suggest surgery for certain underlying causes of arthritis, such as cranial cruciate ligament rupture, elbow dysplasia, osteochondritis dissecans, joint incongruity, intra-articular fractures, and joint instability. Reconstructive procedures can eliminate joint instability and correct the anatomic defects. If your pet has severe hip dysplasia, your veterinarian may suggest a total hip replacement and femoral head/neck ostectomy. If the arthritis is in the wrist or ankle (then joint fusion may be considered; this surgery is usually well tolerated and can result in reasonable functionality.

Monitoring and Prognosis

Your veterinarian may need to do periodic physical examinations every 1-4 months to monitor your pet’s response to therapy and the progression of the disease. In addition, if your pet is on an NSAID, blood tests including complete blood counts and biochemistry profiles, should be done every few months to ensure there are no side effects impacting the liver or kidneys.

With therapy and careful monitoring, arthritis can be managed in many dogs and cats, resulting in a good quality of life that you and your pet will appreciate. 

If you aren’t planning to visit the veterinarian for any other reason, you think, why go in just for a quick nail trim?

So, you have corralled the needed tools for the job, which in your mind are:

     1.  your dog; and
     2.  the nail clippers.

As expected, your always-calm dog sniffs the clippers and holds their paw up for you to begin. Clearly, this is not a big deal. You grasp the paw in your hand and gently expose the first toenail by squeezing a bit. You put the trimmer around the nail and squeeze the handles. With a satisfying click, you see the nail trimming pop away, and at the very same moment, your sweet dog lets out a sharp yelp, frightening you both. And there is blood.

Blood? Why is there blood? That never happens when the veterinarian technician does the nail trimming. 

Your very good dog is still sitting there, looking at you with what you think is betrayed reproach. What now? Panic? No.

Nail Trim Essentials

Let’s back up. 

Let’s return to the last time the veterinary technician trimmed your dog’s nails. This time, really watch the process and ask questions, such as, how short should you trim the nails?

If you aren’t familiar with the term “quick”, it refers to the blood and nerve-filled nail bed. If nails are clipped too short, the quick is nicked, and the nail will bleed. If your dog has fairly clear nails, you can see the quick. If there is an assortment of clear and dark nails, you can judge where the quick might be on the dark ones by looking at a clear nail.

There is a theory that when nails are trimmed or broken, the quick recedes further up the nail. Therefore the“quick line” may not be the same on every nail. If your dog or cat has a nail that seems ragged or shorter than the rest or has a bit of dried blood on it, this nail may have been torn previously. Keep in mind that this nail may not need as much trimming as the longer ones. However, it’s a good idea to clean it up to avoid further tearing.

So, you feel more confident trimming your dog or cat’s nails, right?

Handling “Quicked” Nails:

But now you know that things can happen, and you have revised your list of tools. You gather: 

1. your dog (or cat);
2. nail clippers;
3. clean towel;
4. a paper plate or small dish; and
5. a coagulant to help stop any bleeding.

Over-the-counter coagulants to stop nail bleeding are readily available. Styptic powder is the most common substance used for this type of first aid. Made from natural ingredients, including potassium aluminum sulfate (alum) and diatomaceous earth, styptic powder can be used on minor cuts and toenails. It’s safe for use on pets.

You can find styptic powder at any pet supply store. Your veterinarian probably carries it if the clinic sells over-the-counter products. Corn starch will also stop bleeding effectively, and baking powder or flour can be used as a second choice. Keep styptic powder or one of these products on hand with your nail-clipping supplies.

If a toenail does start to bleed, press the clean towel against the nail and hold it firmly for a few moments. Remove the towel and press the bleeding nail into some coagulant powder you’ve already prepared by pouring it onto the paper towel or dish. Use your fingers to pinch some powder to pack into the nail. Continue to hold the towel firmly around the toe.

You could also use a cotton-tipped applicator with styptic powder on the end and hold that firmly to the toenail.

A few minutes of this will likely stop the bleeding, but if it doesn’t, continue the pressure with the towel and reapply the styptic powder.

If your pet isn’t exactly the quiet dog described here, have someone help you by holding your dog or cat. A trusted pet holder can help calm an upset animal and keep the affected foot still, helping to avoid a mess if your pet flings their paw around. Make sure you have trained your pet prior to beginning nail trims. Food distractions may also be helpful.

While uncomfortable for your pet, a toenail trimmed too short and bleeding is not necessarily an emergency. You will become more confident trimming your pet’s nails and less likely to nip the quick the more times you do it. If the bleeding continues for longer than 10 minutes or is very heavy, call your veterinarian.

On rare occasions, your dog may need to be seen by a veterinarian to assess why a nail is bleeding excessively, and sometimes an injured or broken toenail must be removed in order to heal properly.

These wounds can be sterile, unclean (relatively clean but not sterile), or even heavily contaminated. The body is designed to address all of these situations, and often, as caregivers, we can help.

The Healing Process Starts as Soon as the Wound is Inflicted

There are four phases of wound healing: Inflammation, debridement, repair, and maturation.

Inflammation (Starts Immediately)

This is the first phase of healing and is all about controlling bleeding and activating the immune system. Without going into too much biochemical detail, blood clots are forming, and blood vessels are constricting to limit blood loss in the area. This process also calls in “clean up” cells of the immune system to address contaminating bacteria and any dead tissue.

Debridement (Starts in a Few Hours)

Wound fluid, dead tissue, and immunologic cells form pus, which is designed to flow as a liquid from the wound and carry debris with it. The cells that were called to the wound in the inflammation phase are now actively working on consuming dead tissue and cleansing the area.

Repair (Starts in a Couple Of Days)

Collagen begins to fill in the wound to bind the torn tissues, a process that will take several weeks to complete. New blood vessels begin to grow into the area from the uninjured blood vessels nearby. The wound edge begins to produce granulation tissue, the moist pink tissue that will ultimately fill in the wound. The wound will shrink in a process called wound contraction so that new skin can form and cover it.

Maturation (Starts in 2-3 Weeks and can Take Months or Even Years)

Once plenty of collagen has been deposited, the final phase of scarring can form. The scar becomes stronger and stronger over time as new blood vessels and nerves grow in, and the tissue reorganizes. The final result will never be as strong as un-injured tissue but should ultimately achieve approximately 80% of the original strength

Spay Incision

A spay incision is an example of wound healing by primary intention.

Primary Intention

When the wound is a surgical incision with sutures in place, there is no area for the body to fill with granulation tissue. Instead, the wound margins are already held together and the two margins simply need to bond. New skin begins to form across the margin within two days. The four stages of healing continue as above but go much faster (10-14 days total) because there is no gap in the tissue to fill in.

Healing occurs across the wound margin, not down its length, which means long incisions heal just as fast as short ones.

Secondary Intention

If the wound cannot be closed with sutures (it is too big, there is too much tension on the wound margins pulling them apart, the wound is too infected, etc.), then a process called second intention comes into play. This is the part of wound healing where granulation tissue must form to fill in the gap. Once the wound is filling with granulation tissue, contraction soon follows, which means the wound will be getting smaller and smaller. Eventually, it can be allowed to simply close on its own or when it is small enough, the margins can be trimmed and the wound surgically closed with primary intention of a smaller scar and better fur coverage. In the right circumstances, skin grafts can be applied, but only if there is a healthy granulation bed.

We Love Granulation Tissue

It looks like it would be sore. Many people incorrectly feel granulation tissue is not supposed to be there when, in fact, it is a sign of a healthy healing wound. When a wound is cleansed of debris, scabs, or crusts (and often when a bandage is removed), granulation tissue is evident. Many people, especially those not familiar with wound management, find granulation to be disturbing: it is red or bright pink, moist, bleeds easily, and is often confused with underlying muscle.

Granulation tissue:

1. Should be moist so as to allow better blood flow and a proper debridement phase.
2. Bleeds easily as it is rich in blood vessels.
3. Generally is not painful as nerves grow into granulation tissue late in the healing process.

How Can We Help?

The body is actually pretty good at healing, but there are some things that can go wrong, as well as ways that we can facilitate the healing process.

• Deeper pus pockets must be drained. Eventually, these will probably burst out on their own. Depending on the size of the pus pocket (abscess), a large amount of tissue may slough off when the abscess bursts, so, if possible, the pocket is lanced, flushed, and drained before it gets to that stage. Sometimes, actual latex strips are sewn in place to facilitate pus drainage.
• The wound must be kept moist. This can be accomplished with bandages and/or ointments. A moist wound has better blood flow and can heal more effectively.
  
• Gross contamination should be cleaned up. Dirt, hair, pus, and other bacteria-rich substances should be flushed from the wound. Antibiotics may be needed either orally, topically, or both to address infection.
  
• Dead tissue should be trimmed. If there is non-viable tissue in the wound, it should be removed so the body will not have to liquefy it. This can be done through surgery, through certain types of bandages, or by topical applications, depending on the type of wound.
  
• Wound-enhancing topical products can be applied. There are a number of topicals touted to reduce infection and/or enhance the formation of granulation tissue. It often seems like new products are available annually, so we won’t review them, but your veterinarian may select one to potentially assist the body’s wound healing efforts.

First Aid Tip: If your pet’s wound is fresh and your pet will allow it, try to wash out large debris particles with tap water (saline flush as used for eyes is even better as it is balanced for tissue exposure). Cover the wound with clean, dry bandage material, if possible. See your veterinarian for professional wound care.

Non-healing Wounds

If a wound seems to be ongoing, either healing and then getting worse again or simply not showing signs of healing, be sure to bring your pet to the veterinarian. Unhealing wounds may have tumor involvement or may simply be infected. Do not try to do it yourself and end up with an advanced and possibly untreatable problem.

Be Careful with Seasonal Plants and Decorations

• Oh, Christmas Tree: Securely anchor your Christmas tree so it doesn’t tip and fall, causing possible injury to your pet. This will also prevent the tree water—which may contain fertilizers that can cause stomach upset—from spilling. Stagnant tree water is a breeding ground for bacteria, and your pet could end up with nausea or diarrhea should he imbibe.

• Avoid Mistletoe & Holly: Holly, when ingested, can cause pets to suffer nausea, vomiting, and diarrhea. Mistletoe can cause gastrointestinal upset and cardiovascular problems. And many varieties of lilies can cause kidney failure in cats if ingested. Opt for just-as-jolly artificial plants made from silk or plastic, or choose a pet-safe bouquet.
  
• Tinsel-less Town: Kitties love this sparkly, light-catching “toy” that’s easy to bat around and carry in their mouths. But a nibble can lead to a swallow, which can lead to an obstructed digestive tract, severe vomiting, dehydration, and possible surgery. It’s best to brighten your boughs with something other than tinsel.
  
• That Holiday Glow: Don’t leave lighted candles unattended. Pets may burn themselves or cause a fire if they knock candles over. Be sure to use appropriate candle holders, placed on a stable surface. And if you leave the room, put the candle out!
  
• Wired Up: Keep wires, batteries, and glass or plastic ornaments out of paws’ reach. A wire can deliver a potentially lethal electrical shock and a punctured battery can cause burns to the mouth and esophagus, while shards of breakable ornaments can damage your pet’s mouth and digestive tract.

Avoid Holiday Food Dangers

• Skip the Sweets: By now you know not to feed your pets chocolate and anything sweetened with xylitol, but do you know the lengths to which an enterprising pet will go to chomp on something yummy? Make sure to keep your pets away from the table and unattended plates of food, and be sure to secure the lids on garbage cans.
  
• Leave the Leftovers: Fatty, spicy, and no-no human foods, as well as bones, should not be fed to your furry friends. Pets can join the festivities in other fun ways that won’t lead to costly medical bills.
  
• Careful with Cocktails: If your celebration includes adult holiday beverages, be sure to place your unattended alcoholic drinks where pets cannot get to them. If ingested, your pet could become weak, ill, and may even go into a coma, possibly resulting in death from respiratory failure.
  
• Selecting Special Treats: Looking to stuff your pet’s stockings? Stick with chew toys that are basically indestructible, Kongs that can be stuffed with healthy foods, or chew treats that are designed to be safely digestible. Long, stringy things are a feline’s dream, but the most risky toys for cats involve ribbon, yarn, and loose little parts that can get stuck in the intestines, often necessitating surgery. Surprise kitty with a new ball that’s too big to swallow, a stuffed catnip toy, or the interactive cat dancer.

• A Room of Their Own: Give your pet his own quiet space to retreat to—complete with fresh water and a place to snuggle. Shy pups and cats might want to hide out under a piece of furniture, in their carrying case, or in a separate room away from the hubbub.
  
• New Year’s Noise: As you count down to the new year, please keep in mind that strings of thrown confetti can get lodged in a cat’s intestines if ingested, perhaps necessitating surgery. Noisy poppers can terrify pets and cause possible damage to sensitive ears. And remember that many pets are also scared of fireworks, so be sure to secure them in a safe, escape-proof area as midnight approaches.