The answer is almost always much simpler: cats lick off their hair because they itch and it is important not to launch into treatment with psychoactive drugs until causes of itching have been ruled out. For example, in a recent study of 21 cats referred to the University of Guelph Veterinary Teaching Hospital Behavior Service because of excessive hair licking, only two cats were ultimately believed to have a psychological reason for hair licking, and sixteen cats were found to have a true medical basis for itching, and three cats had both.

But let us go back to the beginning: the cat with a big bald spot.

How Do we Know the Cat’s Hair is not Simply Falling Out?

This turns out again to be the feline nature: refined. Private and refined. In fact, sometimes the mowing cat will have some hot spots as well or a patch of scabs but often there is only a bald area with normal-looking skin exposed.

The truth is simple: there are only a few rare diseases that actually will lead a cat to lose hair in great patches but, if someone still remains skeptical, there is a test called a trichogram that will confirm the answer. A trichogram involves plucking a hair from the affected area. There are most likely at least a couple of hairs in the area but if there are not, hairs from the margin may do as well. Under the microscope, the end of the hair is flat from having been broken off. A hair shedding from the skin will have a tapered, natural end.

Obvious Reasons to Itch

Cats are efficient groomers and can lick away all traces of fleas, so we may need to go by the pattern of hair loss, (lower back, possibly including scabbing around the neck). hair loss that changes with the seasons and response to flea control. The first step is virtually always going to be ensuring immaculate flea control. After fleas have been removed from the picture, the cat can be reassessed in a couple of months for hair regrowth and/or with a fresh trichogram. If fleas are not obvious right from the beginning, again, they should not be considered ruled out as a cause, but further investigation will be needed. 

The first step is virtually always going to be insuring immaculate flea control. After fleas have been removed from the picture, the cat can be reassessed in a couple of months for hair regrowth and/or with a fresh trichogram. If fleas are not obvious right from the beginning, again, they should not be considered ruled out as a cause but further investigation will be needed.

To properly determine if there are fleas in the household, a flea comb is especially helpful. Flea combs have narrow teeth that can trap live fleas and flea dirt. The cat who is mowing may not have evidence of fleas, but if there are fleas on one of the other pets in the house, you can bet the mowing cat has them too.

• A fecal flotation test for parasites (occasionally intestinal worms will create itching in the skin. Also, Demodex mites sometimes show up in the fecal test rather than the skin scrape because the cat has been so efficient at licking them up.)
  
• Checking the ears with an otoscope (even if the itchy areas are distant from the ears, sometimes ear mites travel out of their normal homes in the ear canal).
  
•  Inspection of the cat with a Wood’s light (a fluorescent light – hairs infected with ringworm fungus often glow in the dark) plus a test for ringworm. The culture will require approximately ten days to grow. 

If these non-invasive procedures have not yielded the answer, then there are some choices to make in the approach. Your veterinarian may have a preference as to the order, but the following are several possibilities that might be chosen, each answering different questions.

Skin Biopsy

This can likely be accomplished the same day as the initial visit and yield results as soon as 48 hours later. It is important that the samples be read by a pathologist who specializes in reading skin tissue so your veterinarian may want to request an expert or use a specific laboratory. In this procedure, a local anesthetic is injected into selected areas of skin and an instrument called a punch biopsy (which resembles a tiny cookie cutter) is used to remove small plugs of skin.

The cat will probably have a stitch in each area where a sample was taken.

1. The absence of abnormalities in the tissue virtually confirms a psychological (the correct term is psychogenic) cause of the mowing. (In the Guelph study mentioned above, three cats had both psychogenic mowing AND medical disease.)
2. Ringworm can be confirmed more quickly than with the culture (the culture sometimes picks up ringworm when the biopsy does not, though, so doing both tests is very reasonable).
3. Allergies should be readily identified (though it will not be possible to tell what type of allergy: insect-related, food, or airborne).

Food Allergy Trial

The only way to determine if the cat has a food allergy is to put the cat on a trial diet that the cat could not possibly be allergic to (either a hydrolyzed protein diet or a novel protein diet) for a long period of time and see if the mowing stops. How long? Many cats respond in three to four weeks but some require a good 2 months, so to be sure, a two-month trial is typically recommended.
The advantage of this test is that it can make the correct diagnosis and provide treatment.

• The advantage of this test is that it not only can make the correct diagnosis but also provides treatment.
  
• There are two important disadvantages of this test. The first is that no results will be available for potentially two months. The second is that many cats are picky about the diet food and it may be hard to find one the patient likes. If the cat goes outside, it will not be possible to do a food trial as it will not be possible to control what the cat eats.

See our related page on food allergies for more details.

Flea Control Trial

As mentioned, immaculate flea control is very important in ruling out fleas as a cause of mowing, and it is crucial not to assume that if fleas are not seen, then they must not be involved. There are numerous sophisticated flea products available, and every veterinarian has a favorite. Your veterinarian will instruct you on a schedule for use in this situation it may be more frequent than the manufacturer’s recommendation). The trial should continue for at least 6-8 weeks, after which the cat can be reassessed for hair regrowth or reduction in licking.

• This trial only answers the question of whether or not the problem is flea-related, and it takes approximately two months to do so.
  
• To properly determine if there are fleas in the household, a flea comb should be used, ideally on a pet that is not itchy or mowing. Flea combs have narrow teeth that can trap live fleas and flea dirt.

In an effort to save time, the food trial and flea control trial can be done at the same time. If the cat has not responded after two months, another disease/condition can be pursued. If the cat responds after two months, the cat can be challenged with the original diet. If mowing recurs (which generally takes two weeks at the most on the original diet), then the food allergy is the answer. If the cat continues not mowing after the original food is introduced, then the problem is flea-related.

Demodectic Mange Dipping Trial

Demodectic mange mites can be difficult to find in cats, especially if the cat is over-grooming. It is important to realize that a negative skin scrape does not mean that the cat doesn’t have mites. Fortunately, there is another way to determine if the cat has Demodex mites; the cat can be treated for mites to see if the mowing stops. The cat is treated with lime dip weekly for three weeks. If there is improvement in hair regrowth or a reduction in self-licking, then three more weekly dips are done for a total of six dips, and any other cats in the house are also treated with a total of six dips. Lime sulfur dip is not pleasant. It stains fabric and jewelry and smells like rotten eggs. For these reasons, many cat owners opt for dipping to be done in the hospital rather than at home.

Demodex mange mites are more common in certain geographical areas (such as the Southern U.S.) than others. At which point a dipping trial should be done depends in part on the likelihood of demodicosis being the problem. If Demodex mites are not found on a skin scraping, and they frequently are not even if they are in the skin, then the response to dipping becomes the only way to determine if the cat has them.

Lime sulfur dips are very drying to the skin, and special conditioners may be needed after the third dip if dipping is to continue.

Steroid Trial

For this trial, the patient receives some kind of cortisone-type treatment for three to four weeks. At the end of that time one can tell if the mowing has improved (and the mowing is said to be steroid responsive) it hasn’t improved at all (and the mowing is said to be steroid non-responsive.) Knowing whether or not the mowing is steroid-responsive helps classify possible causes. For example, seasonal steroid-responsive mowing is most likely to be from fleas (technically, allergy to the flea bite) or an airborne allergy. Non-seasonal steroid-responsive mowing is most likely going to be from a food allergy or from demodicosis. Steroid non-responsive mowing is most likely to be from a parasitic or fungal problem or a food allergy.

Many experts like to do the steroid trial at the beginning of the workup while others wait until more results are in.

1. The use of steroids can make ringworm worse so many experts prefer to hold off steroids until the ringworm culture is finished.
   
2. The use of steroids will interfere with a skin biopsy. If a biopsy is being considered, it should be done prior to steroid use.
   
3. The use of steroids will interfere with food trials or flea control trials.
   
4. The steroid trial is inexpensive and one of the least labor-intensive tests that can be done.

What if the Cat Really has Mental Illness?

This is generally called psychogenic mowing. We don’t imply that we know if cats are licking out of obsession, anxiety, or even boredom. We simply say that there is nothing wrong with the skin. The approach is aimed at environmental enrichment. This means the cat gets more toys, more games (feeding in a different location daily to create a hide-and-seek sort of cat entertainment), and more attention. See more information on environmental enrichment for cats. 

As for anxiety, there are several approaches. Feliway® products employ a pheromone that is naturally made by cats to communicate that a territory is safe and secure. This pheromone is available in a room spray or a plug-in defuser. Alpha-casozepine is a cow’s milk protein with mood-stabilizing properties. It can be given as an oral supplement (Zylkene^®) or in a commercial diet (talk to your veterinarian). There are also medications for anxiety: clomipramine, fluoxetine, and even amitriptyline. These can be used to relieve a cat’s need for compulsive over-grooming after more conventional causes of itchy skin have been ruled out.

Overall, fur mowing can be a frustrating condition for which no cause is obvious, and the only solution is to try different treatments and see what happens. Hopefully, this article has provided some meaningful suggestions for testing and treatment approaches.

A general physical examination involves an inspection of the teeth and mouth, provided that the patient is of a cooperative nature. We see plaque build-up, tartar, missing teeth, and all sorts of dental conditions that result from a lifetime of basically no toothbrushing (sadly, the norm for cats) but sometimes we see a certain type of gingivitis.  In this situation, the gums are bright red and inflamed, especially in the area in the back of the mouth where the upper and lower jaws hinge together. This area is called the palatoglossal arch or sometimes the fauce.

Consider a cat’s mouth. If the teeth show fairly moderate to heavy tartar deposits, but the uninvolved soft tissues of the mouth are relatively normal, that cat would need a dental cleaning and perhaps even some extractions to restore the mouth to health. Most cats have some degree of periodontal disease if their teeth are rarely brushed. There is associated gum disease with periodontal disease, and most cats do not have to contend with oral disease beyond this. Plasma cell stomatitis is different.

A biopsy is necessary to confirm the diagnosis of plasma cell stomatitis, but the inflammation around the fauce area is often used as the sole diagnostic criterion.

How Do Cats Get this Disease?

Sadly, we do not know how cats get this condition, and until we do it will be hard to prevent. Multiple factors appear to be at work. The condition seems to result from an inappropriate immune reaction against the plaque that forms on the teeth or other oral antigens. 

How Do we Treat it?

No single treatment seems to be appropriate for every patient but the basic principles in treating feline caudal stomatitis involve plaque control, inflammation control, pain control, and nutritional support.

Full Mouth Extractions

Though it may seem dramatic, the best way to control the ongoing oral reaction in this situation is to extract the teeth. Generally, all the molars and premolars (all the teeth from the fangs back to the throat) must be removed including any root tips. Some cats must have the fangs and the tiny incisors between the fangs removed as well, but most cats are controlled with just back teeth extractions.

Full mouth extractions may seem extreme, but this approach yields the best long-term results for most patients. In one study of cats with plasma cell stomatitis that had their molars and premolars extracted, 20% were improved to a point where medication could control the pain and inflammation, and 60% were cured outright with no further treatment needed. The 60% number was increased to 90% when the canine teeth (fangs) were extracted as well.  

Most of the cats that did not do well with full-mouth extraction had been on medical management for months to years before the extraction (there is a point where the inflammation is too well seated for extraction to work). The take-home lesson is not to consider full-mouth extraction to be a last resort but to pursue it early in the course of the condition so as to get the best possible results. 

Full-mouth extraction is not inexpensive. Your veterinarian may not be comfortable doing this, and you should discuss whether referral to a dental specialist is in the best interest of you and your cat. 

Dental radiography is a must to make sure all the root tips have been removed, and proper burring of the tooth socket is needed to ensure the periodontal ligament has been fully obliterated and will not cause ongoing inflammation. Pain medication is typically prescribed after extractions of this extent, but it is common for owners to report that cats appear less painful right away than prior to the extractions and accept food hungrily for the first time in months.

Lack of teeth does not hamper a cat’s ability to eat in any way as food is commonly swallowed whole.

Inflammation and Pain Control (Management with Medications)

Caudal stomatitis is an immune-mediated disease so medical management is centered on suppressing and controlling the excessive activity of the immune system. Cortisone-derivative medicines such as prednisone or triamcinolone are often helpful in relieving inflammation. Again, because of the pain, oral medication may be difficult to administer. A compounding pharmacy can be used to convert the tablet into a palatable liquid but often a long-acting injection is needed to initiate treatment.

Frequently, long-acting injectable steroids such as methylprednisolone acetate (Depomedrol®) are used with favorable responses generally observed within one to two days. This may be helpful particularly when the cat is so painful that he cannot accept food; within days of treatment, the swelling and pain are alleviated greatly. Steroids such as these, however, are problematic with long-term use and should be considered a temporary solution only. Methylprednisolone acetate injections are associated with the development of diabetes mellitus plus their immune-suppressive nature may empower an underlying calicivirus infection and/or periodontal bacterial infections.

Cyclosporine, another immune-modulating medication, is gaining popularity for the treatment of caudal stomatitis inflammation. This product is available as an oral liquid and has fewer associated side effects compared to steroids. Rapid results are not seen as with the steroids, but sometimes they are given together so that the cyclosporine has had time to reach its peak effect just as the steroid injection is waning.

Bacterial infection complicates plasma cell stomatitis so antibiotics such as Clavamox or clindamycin are often prescribed, sometimes for long-term use (at least 4 weeks). These antibiotics are especially good for oral infections as they target anaerobic bacteria that live in the mineralized plaque covering the teeth. Other antibiotics that might be recommended include metronidazole, doxycycline, and azithromycin. A long-acting injectable antibiotic called cefovecin (Convenia®) is often used since no oral manipulation is needed and one injection lasts two weeks, precluding manipulation of a very painful mouth.

During a particularly painful flare-up, sometimes a fentanyl patch is helpful for pain control. This is a small plastic patch that is generally applied to the back of a foot. It releases a continuous supply of pain relief for five to seven days. Buprenorphine is another popular pain reliever for caudal stomatitis patients as it requires less oral manipulation; the liquid is simply squirted into the mouth and is absorbed directly with actual swallowing being unnecessary.

Miscellaneous Medications/Treatments

Pentoxifylline helps red blood cells become more flexible, thus allowing oxygen to be carried deeper into damaged tissues to facilitate healing. It is emerging as an adjunctive treatment for caudal stomatitis.

Maropitant citrate (Cerenia®) was developed as a strong anti-nausea medication but its unique mechanism of regulating the interaction of Substance P and the N-K Receptor has led to numerous uses for it. It appears to have pain-relieving and anti-inflammatory properties beyond its stomach-settling ones.

Other medications to try might include the use of interferon omega, an immune modulator that theoretically helps normalize immune reactions. This treatment has been effective for cats needing additional therapy after extractions yield only partial improvement, but it is not available in North America.

Bovine lactoferrin is a natural compound that is similarly immunomodulating and antibacterial. It can be formulated by a compounding pharmacy into a palatable liquid. Bovine lactoferrin is used to bathe the mouth tissues. Initial studies showed a large percentage of affected cats responded at least partially.

Hypoallergenic Diets are single protein source diets or even hydrolyzed protein source diets used in the diagnosis and management of food allergies.  While plasma cell stomatitis is not a food allergy, there is a theory that food antigens may be involved in generating oral inflammation. Using a hypoallergenic diet limits antigen exposure which may be helpful.

It is important to remember that medical management is not the first choice approach for most patients and that medications tend to get less and less effective over time. Extractions are best done early. Medication is helpful to get long-standing pain controlled quickly and as a supplement to patients who do not respond completely to extraction.

Summary

1. Caudal stomatitis is a painful, chronic condition.
2. Proper diagnostics including a mouth biopsy are needed to confirm the diagnosis and get the correct treatment.
3. Extraction of the molars and premolars early in the course of disease yields the best long term results in most patients. Medical management is for specific situations (flare ups, patients who need more than extractions, patients with no tooth-associated lesions).
4. This disease can be frustrating to treat.

Cats retain many behaviors of their wild ancestors. As predators, they have strength, agility, speed, and keen senses to catch prey effectively. Owners can help their feline friends express these natural skills during mealtimes. Food enrichment provides physical and behavioral well-being for the cat and enjoyment for the family.

Use the following tools to feed part of the daily meal or special treats. Many diets, including prescription diets, can be enhanced with wet or dry foods.

• Let your cat watch you fill the puzzle and sit with them while they work.
• Quickly slide a piece of kibble across a smooth floor for running and pouncing fun.

Safety Tips

Supervise pet interactions when using these in a multi-pet household.

Observe your cat during food enrichment to be sure they don’t get stuck, injured, or become frustrated.

Small meals in feeders prevent gulping and may lessen vomiting.

Dogs are lucky, as only about 50% of mammary tumors are malignant for them. For cats, approximately 90% are malignant with rapid spread to adjacent glands and the nearest set of lymph nodes. Cats generally have four pairs of mammary glands (thoracic, cranial abdominal, caudal abdominal, and inguinal – see the illustration). The most commonly affected glands are the thoracic and inguinal glands. An owner should be accustomed to feeling for even small lumps in these areas. Because veins connect both the right and left sets of glands, it is easy for tumor cells to cross from one side to the other, though usually, the glands on the same side as the original tumor are seeded first.

Tumors removed when they are less than 0.8 inches (2 cm) in diameter have a median survival time of four and 1/2  years. Tumors removed when they are greater than 1.2 inches (3 cm) in diameter have a 6-month median survival time.

Tumors spread from the mammary glands to local lymph nodes and then on to the chest, brain, bone, and even spleen. Chest radiographs will be needed to assess tumor spread before surgery can proceed. Basic blood tests will also be needed.

Risk Factors for Mammary Cancer

1. Not surprisingly, being female is the most significant factor.
2. Siamese cats are overrepresented. They also tend to develop mammary tumors at a younger age than other breeds (nine years is average for Siamese and 14 for non-Siamese).
3. Exposure to progestin hormones (not used much anymore but previously used for behavioral issues such as urine marking) is a risk factor.

Protective Factors

Early spaying is the single most significant protective factor. Spaying before age six months results in a 91% reduction in risk. Spaying before the age of one-year results in an 86% reduction in risk. Spaying before the age of two years leads to an 11% reduction in risk. Having given birth to kittens has no effect on mammary cancer risk.

Cats spayed before age six months have a 9% rate of mammary cancer development later in life. Cats spayed between ages six and 12 months have a 14% incidence of mammary cancer development later in life.

Types of Tumors

Feline mammary tumors are generally either carcinomas or adenocarcinomas. Papillary or tubular carcinomas tend to be the least aggressive. Ductular carcinomas seem to kill cats about four times faster. Anaplastic carcinomas are the worst kind, usually dispatching the patient three times faster than that.

The pathologist examining the biopsy tissue uses different cellular criteria of malignancy to grade the tumor as Grade I, Grade II, or Grade III. A grade I tumor generally has a good chance of a one-year survival time, depending on its size and tumor type. Grade II tumors have a 57% chance of survival after a year unless chemotherapy accompanies surgery. Grade III tumors treated with surgery alone had no survivors at one year from the time of diagnosis.

Treatment: Surgery

There is not usually enough skin to remove both mammary chains on the same surgery so it is common to allow three to five weeks of healing time between the removal of each chain. Removing both chains not only prevents the tumor from crossing to the other side but it prevents development of a new tumor or the second side as well.

If only one side is involved but is deemed too advanced for cure, removing the second mammary chain is likely not worth it.

Aggressive surgery yields a disease-free interval of 1 year in about 50% of cats and 2 years in 32% of cats. If lymph node involvement is already present at the time of surgery or if the tumor recurs after the first surgery, then 51-66% of cats will have a 5.5-month disease-free interval.

If the tumor is in an obviously advanced state at the time of the first surgery, then a less aggressive surgery to palliate the infection may be more appropriate. This will at least make the cat more comfortable by losing the smelly, infected external tumor. Alternatively, radiation therapy can be used to temporarily “dry up” the stinky leaking gland, especially if the cancer poses too great an anesthetic risk for tumor removal.

Treatment: Chemotherapy

To maximize disease-free intervals, surgery is followed by chemotherapy. The most common drugs used are adriamycin and cyclophosphamide. This combination was tested in a group of cats who had either incomplete surgical removal of their tumor or obvious tumor spread to lymph nodes or beyond at the time of surgery. About 50% of cats showed at least some response though 21% actually achieved remission (i.e. no detectable tumor, at least temporarily).

In the 50% of cats that showed at least some response to therapy, median survival time increased to 150 to 180 days as opposed to 75 to 86 days in the 50% that did not respond. In studies where adriamycin was used alone, survival statistics were not improved over surgery alone – meaning the cancer still spread – but the disease-free interval was increased, meaning the patients felt good longer.

Not all veterinarians are comfortable treating mammary gland cancer. Discuss with your veterinarian whether a referral to a specialist would be best for you and your pet.

How Do Cats Die from this Disease? When is Euthanasia the Right Choice?

There are two problems that tend to lead to the cat’s demise. One is simply the infected ulcerated external tumor. The primary tumor smells rotten and bleeds. Secondary tumors arise and also break through the skin. Cats are fastidious creatures and do not like having growths of this type on their bodies, plus owners tend not to like rotten, bleeding flesh in their homes. Cats are commonly euthanized due to the progress of the external tumor.

The other problem is tumors spread to the chest. The lungs are invaded by tumor cells, and ultimately, the cat will not be able to breathe.

Cats with advanced lung involvement at the time the tumor is diagnosed have a median survival time of only one month.

Life quality decisions for cancer patients are difficult as the disease progresses inexorably but slowly, and there are good days mixed with bad days. Quality of life issues center around inherent discomfort from the disease versus enjoyment of other aspects of life (socialization, appetite, etc.). Criteria for a euthanasia decision are largely personal, but some guidelines have been established to assist in making this difficult decision. See our quality of life scale to assist you in determining when the time is right. Remember, your veterinarian is available to discuss life quality issues if you need additional guidance.

The term scabies is somewhat colloquial and refers to a mite infection with any of the mites in Sarcoptidae family. Many veterinary dermatologists never see this condition in their entire careers; in the United States, notoedric mange is considered rare with regional hot beds of infection.

How is Diagnosis Confirmed?

A scraping of the crusty skin can be examined under the microscope. Mites and/or their eggs are generally not difficult to detect if they are present; still, their absence does not rule out notoedric mange. Sometimes a trial course of treatment is needed to fully rule out the infection. The mite is highly inflammatory, hence the intense itching. 

Consider that when one cat at home is diagnosed with this condition, all cats at that home may require treatment.

Treatment

There are several options for the treatment of this condition.

Isoxazoline Class Flea Control Products 

At present, there are three products labeled for feline use: Fluralaner (Bravecto®), Lotilaner (Credelio®) and Saralaner (Revolution Plus®). These medications are the newest insecticides for cats and have become popular for killing fleas and ticks but they are also effective against mites such Notoedres cati. None of these products is actually approved for use against Notoedres cati; because of the rarity of Notoedres it is unlikely that any company will pursue official approval. A single dose should be effective and regular use of these products for flea control should be preventive.

Selamectin (Revolution® and Revolution Plus®) 

This topical medication was designed for flea, heartworm, and intestinal parasite control. In dogs, it is approved for control of sarcoptic mange mites but due to the rarity of Notoedres cati, as noted above, the manufacturer is unlikely to pursue the expensive process of gaining FDA approval for Notoedric mange. Still, selamectin, is effective against Notoedres cati and regular use of it for flea control seems to be preventive. 

Moxidectin (Advantage Multi® and similar brands) 

This product is another monthly topical flea preventive similar to the other ones listed. As with the others, regular use is preventive. Advantage Multi is used against fleas, ear mites, heartworm, roundworms, and hookworms. 

Ivermectin

Usually given as an injection, this medication was one of the first treatments used against Notoedres cati. It is still used today. Treatment is typically weekly or every 2 weeks for a month and recovery is prompt. Doses approved for heartworm prevention in cats are not high enough to treat Notoedric mange; different dosing is needed.

Dipping 

In the past, a series of six or seven lime sulfur baths or amitraz dips were used to control this infection. While this certainly works, the cat’s general dislike of bathing created need for something more convenient. Furthermore, lime sulfur has an extremely objectionable smell and will discolor fur. Amitraz tends to produce sedation in some patients and headaches in some humans. Not surprisingly, this method is rarely used nowadays. 

This is Pete before and after he was treated with one dose of ivermectin.

What are Myeloma-related Disorders?

Myeloma is a type of cancer that affects plasma cells. Plasma cells are specialized lymphocytes, i.e. they are part of the white blood cell group and are key components of the immune system. In the healthy individual, plasma cells are responsible for making antibodies and help protect against disease. Plasma cells that become cancerous are known as myeloma cells. A broad spectrum of different clinical signs may develop as myeloma cells proliferate, making this a difficult and challenging disease to diagnose and treat.

Currently reported feline myeloma-related disorders include:

1. Myeloma
2. Cutaneous extramedullary plasmacytoma (CEMP)
3. Non-cutaneous extramedullary plasmacytoma (NCEMP)
4. Solitary plasmacytoma of bone (SPB)
5. Waldenströms (IgM) macroglobulinemia (WM)
6. Immunoglobulin-secreting lymphoma
7. Myeloma cell leukemia

Otto Kahler (1849-1893), a physician from Prague, is accredited with the first medical description of myeloma in humans.  Incidentally, the word myeloma is derived from two parts: myelo from the Greek word muelos meaning marrow, and oma, a Greek suffix commonly used to denote a tumor. The first description of myeloma in cats was not used until 1957 and was published by Holzworth & Meier from the Angel Memorial Animal Hospital in Boston. Many more reports on this condition now exist, but overall the myeloma-related disorders are relatively rare tumours in cats.

What Signs are seen with Myeloma-related Disorders?

Symptoms can vary tremendously within the same patient over time, as well as between patients. Clinical signs are dependent upon the location(s) the myeloma cell is proliferating in, as well as signs attributable to the excess production of antibodies by these cancerous myeloma cells. Furthermore, these tumors show differing patterns of clinical signs between different animal species.

Cats with myeloma commonly have anemia and this can contribute to the lethargy and weakness that may be seen. The cancerous myeloma cells typically produce immunoglobulins (monoclonal antibodies), which are often referred to as a paraprotein or M-protein. Filtration of the paraprotein by the kidneys leads to abnormal kidney function and even kidney failure. Excessive levels of paraprotein increase the “thickness” of the blood and result in hyperviscosity syndromes that may damage the eye (causing blindness), the nervous system (causing nerve or brain signs), the heart (cardiomyopathy), or in blood clotting (bleeding tendencies).

The myeloma cells can congregate in clumps in various internal organs (e.g. in cats, the liver and/or spleen are commonly affected) or within skin, causing isolated tumors (or plasmacytomas), that can interfere with the normal function of these organs or the surrounding area. If the myeloma cells proliferate in the marrow – as happens in some cats, but is more common in human patients or dogs –  then destruction of bone can be seen (also known as osteolysis) causing bone pain or even fractures. Myeloma cells can also disturb the control of key body chemicals (such as calcium metabolism). Patients with myeloma can also be immunosuppressed and have a reduced ability to fight infections.

Treatment and Survival in Myeloma-related Disorders

Before commencing treatment, a complete diagnostic work-up is strongly recommended. The goal in treating multiple myeloma is to improve quality of life, relieve symptoms and pain if present, and to prolong survival. Complete cure has not been reported. Complete remission (meaning the alleviation of clinical signs) can be achieved. In one report, the majority of cats responded to combination chemotherapy and these cats had a median survival time of 12 months, which is not dissimilar to some reports for the treatment of standard lymphoma. Disease control is usually eventually complicated by a tendency for myeloma cells to become resistant to anti-cancer drugs.

What should I do if Myeloma is Suspected in my Pet?

Complete investigations for myeloma-related disorders are complex and may take several days. Ideally, referral to a veterinary oncologist in a multi-disciplinary specialist centre is in the best interests of the patient. Please draw the attention of your primary or referral veterinarian to the information available at and the clinical research being conducted at the Veterinary Myeloma Website.

Manx Syndrome in Cats

Manx syndrome (sacrocaudal dysgenesis, sacrocaudal agenesis) is an array of problems involving the function of the hind legs, urinary bladder, and colon of a tailless cat. In affected cats, the spine and spinal cord are shortened because the last few vertebrae and spinal segments have not developed normally.  

Inheritance

Manx syndrome is inherited as an autosomal dominant trait in the Manx cat, meaning the Manx syndrome trait can be passed down from just one parent’s genes and the offspring will have the trait. However, the degree of spinal malformation can vary. All Manx cats, with or without a tail, have the mutant gene and can produce tailless offspring. Neurological problems are most common in tailless cats.

Signs

Some tailless cats have mild or no neurologic changes, while others have severe neurologic deficits.

Signs depend on how severely the cat’s spinal cord is affected. Significantly affected cats may die in utero or be euthanized soon after birth. Signs are usually recognized when the kitten starts to walk, anywhere from weeks to months after birth.

Clinical signs may include an abnormal pelvic limb gait (back legs), urinary and fecal incontinence, lack of sensation in the hind legs and around the openings of the anus and urethra, and some level of hind-end paralysis. Those cats whose hind legs do not function the way they should are usually unable to participate in some typical cat behaviors, such as jumping, and need to be kept as indoor cats.

Signs can include:

1. Tailless
2. Urinary or fecal incontinence
3. Secondary urinary tract infections
4. Urinary scalding and staining
5. Constipation
6. Partial paralysis of the hind legs, which can cause difficulty walking
7. Bunny hopping gait
8. Lack of sensation of the skin around the anal/perineal area
9. Stance in which the cat walks on their entire foot instead of the toes
10. Rectal prolapse
11. Some cats may develop megacolon, where the colon becomes abnormally dilated and loses its ability to contract due to long-term, chronic constipation. 

Diagnostics and Treatment

Your veterinarian will take a thorough medical history and perform a complete physical examination to make the diagnosis. Some radiographs or other imaging tests may be recommended, as well as a urinalysis, a neurologic examination, and a bacterial culture to test for a urinary tract infection.

There is no curative treatment. All that can be offered is supportive care and keeping the cat clean while managing any incontinence, hygiene, megacolon, urinary tract infections, and constipation. Daily grooming is necessary for cats incapable of controlling their bowels or bladder as chronic skin contact with urine or feces can start an ongoing struggle with lifelong skin irritation and urinary infections that must be treated. If your cat is incontinent, your veterinarian can show you how to manually empty the bladder to help prevent urine scald and bladder infection. Diapers can be used to prevent soiling if your cat will tolerate them. Stool softeners can help ease constipation.

Prevention

Parents of affected cats should not be bred again to prevent suffering.

Lymphoma is, at this time, the most common malignancy of cats, accounting for as much as 30 percent of all feline cancers. Luckily, it is just as responsive to medication as it is in dogs and prolonged remissions are common. This article reviews the common forms of lymphoma in cats, including diagnosis and treatment expectations.

Lymphoma is a cancer made of lymphocytes and these lymphocytes readily travel throughout the body via the lymph system. Because of all this traveling, lymphoma is only a localized problem in rare situations so surgery and radiotherapy are not appropriate as sole treatments. To reach cancerous lymphocytes in all the places they have gone, medication (chemotherapy) is necessary because medication can be carried all over the body via the circulation. Treatment of lymphoma is going to involve pills and/or injections for your cat regardless of which form of lymphoma has been diagnosed.

Classification by Anatomical Location

As in dogs, one of the more common ways to classify lymphoma is by the anatomical area where the cancer is mainly located. In dogs, the most common form of lymphoma is the multicentric form where many (if not all) of the body’s lymph nodes seem to enlarge and fill with cancer cells at the same time. Cats are certainly able to develop multicentric lymphoma as well, but by far the most common form of lymphoma in cats is the intestinal form so most of our discussion will center there. Other notable forms of feline lymphoma include: renal (kidney) lymphoma, nasal lymphoma, and mediastinal lymphoma.

Intestinal Lymphoma

As mentioned earlier, lymphoma can develop anywhere there is lymph tissue and virtually all organs have some bits of scattered lymph tissue associated with them. It is not clear why some areas seem to be especially vulnerable to developing lymphoma over others.

Intestinal lymphoma may be a distinct mass or growth or group of growths, or appear as a more subtle infiltration of cancerous lymphocytes into the delicate membranes of the bowel lining. Infiltrative lesions, which are often invisible to the naked eye, generally respond to chemotherapy; surgery is not necessary or even helpful. Distinct masses, however, can cause an acute obstruction and may require surgical removal to relieve this potential emergency. Removing these masses does not control the cancer and chemotherapy is still needed after the surgical site has healed.

Diagnosis

Confirming lymphoma requires a sample of tissue, ideally a small chunk or at least a smear of cells. There are several ways tissue can be harvested for analysis.

Surgical Biopsy

Surgical biopsy involves opening the abdomen and removing pieces of tissue for analysis.

Pros: Maximum access to the organs of the abdomen, ability to sample the full thickness of the intestine and see how deep the abnormal cells penetrate. This type of sample not only distinguishes benign versus malignant disease, but also allows for grading of the lymphoma, which is important in prognosis (see below). Cons: Invasive. Requires general anesthesia and hospitalization. Also, chemotherapy must be delayed until the surgery site has healed.

Endoscopic Biopsy

Involves the use of a long scope inserted into the mouth and/or anus to view the intestine and stomach from the inside. A small “biter” is inserted through the scope that can bite out little pinches of intestinal tissue; these biopsies are not full thickness but the scope allows for specific areas to be sampled. Pros: Far less invasive than surgical exploration with patients generally going home the same day as the procedure.

A quality biopsy, as mentioned, distinguishes benign versus malignant disease and allows for grading. Chemotherapy need not be delayed after results are obtained. Areas that might not look abnormal when viewed externally may look very abnormal when viewed from inside the intestine, and endoscopy allows for any such specific areas to be biopsied. Cons: Does not always produce quality samples as readily as surgery. Endoscopic samples are smaller, not full thickness, and may be squashed by the biopsy biter, making interpretation more difficult. Also, only the intestine is accessible; other organs are not.

Needle Aspirate

Involves removing a sample of cells from a larger organ or from a mass with a needle, usually with ultrasound guidance. Pros: Anesthesia is rarely needed and procedure is less invasive than the other two methods. Cons: Cells are withdrawn without their tissue architecture, which means some accuracy is sacrificed. Non-diagnostic samples are not unusual. The intestine itself cannot be aspirated, only masses and organs (local lymph nodes, the liver etc.)

Lymphoma has the ability to be quite subtle in its manifestation, but if the appearance of the bowel on ultrasound is classical, it may be reasonable to begin treatment based solely on this information and forego the more expensive/invasive biopsy procedures.

Learn more information on infiltrative bowel disease and the pros and cons of treating it without tissue sampling.

Another way that ultrasound might negate the need for further procedures is by obtaining a diagnostic aspirate. If there is a mass or if the local lymph nodes are enlarged, they may be aspirated as described above. If the cells obtained indicate lymphoma is present, then the diagnosis has been adequately obtained.

Furthermore, often the appearance of the intestine and lymph nodes is ambiguous. In this situation, the liver can be aspirated despite its normal appearance. Often lymphoma can be found hiding out there. Again, if a diagnostic aspirate is obtained via ultrasound, it is not necessary to pursue surgery or endoscopy.

High Grade versus Low Grade

One of the advantages of having an actual tissue sample is the ability to grade the malignancy of the lymphoma. Lymphoma is graded by the pathologist reading the biopsy sample as either high-grade, low-grade, or intermediate grade. The grade refers to how rapidly the cells appear to be dividing and how malignant they appear with high grade being the most malignant. The grade of lymphoma bears on its response to chemotherapy (see below). It may be possible to grade a lymphoma with an aspirate sample but it is vastly easier with an actual chunk of tumor. As a general rule with lymphoma, higher grades tend to be more responsive to chemotherapy drugs. With feline intestinal lymphoma, however, it is the low grade cases that achieve remission easier and for prolonged periods of time.

Treatment

As with most forms of lymphoma, treatment centers on medication rather than surgery or radiation therapy. The use of medication to treat this disease is called chemotherapy, a term fraught with unpleasant connotations. It is important to realize that cats rarely experience nausea, poor appetite, or malaise with their chemotherapy and you should not make decisions thinking the cat will be put through some kind of difficult procedure. Instead, the difficulty centers not around side effects, but around giving daily medication to a cat and regularly bringing the cat to the vet’s office for injectable treatments and monitoring tests.

High grade (also called lymphoblastic) lymphoma is bad news. Only 25-50% of cats achieve remission and those that achieve it generally sustain it for only 2-9 months.

Fortunately, most feline lymphoma is the low grade (also called lymphocytic) form of lymphoma. This form behaves much more like inflammatory bowel disease, and, in fact, treatment for severe IBD is largely the same as for low-grade intestinal lymphoma. Approximately 70% of cats with this form of lymphoma will achieve remission and the median survival time is 23-30 months. Treatment for this form of lymphoma generally involves oral medication: prednisolone and chlorambucil. Many people opt to treat with these two medications based on ultrasound appearance of the GI tract, playing the odds that there will be a response. Given the expense of more accurate diagnostics, this may be a reasonable alternative approach.

With chemotherapy, the kidney enlargement reduces and often kidney function improves until remission is lost. Median survival is only 3 to 6 months, though a recent case report highlighted a cat who lived many years, so long remission times are not impossible. Approximately 50 percent of cats with renal lymphoma are also positive for the feline leukemia virus, which carries the potential for other complicating issues.

Unlike other forms of lymphoma, renal lymphoma has a strong association with tumor spread to the nervous system (brain or spinal cord). This makes for an unpleasant complication and, unfortunately, this occurs in up to 40 percent of renal lymphoma cats.

Mediastinal Lymphoma

The mediastinum is not a structure with which most people are familiar. Most people know the chest cavity contains the heart and lungs and some other affiliated structures. But these organs are not just loose and flopping around in the chest, and they are not simply held in place by gravity. The mediastinum is a sheet of connective tissue that bisects the chest, contains the heart, esophagus, trachea and other central structures similar to a vacuum-packed plastic bag. The mediastinum divides the chest into right and left halves and stabilizes the location of the organs in the middle.

Of note in the lymphoma situation are the thymus gland (generally atrophied in adult animals) and the mediastinal lymph nodes. These are lymph system tissues and they become the seat of mediastinal lymphoma.

Because distant disease is addressed with chemotherapy and it is assumed that lymphoma patients have distant disease with their local disease, most nasal lymphoma patients receive chemotherapy.

Prolonged remission times (median survival times over 500 days) are possible with treatment.

You have probably heard the warnings given to pregnant women about cleaning litterboxes and the dangers of ingesting raw/undercooked meat or milk products.

But should you be concerned about how this parasite affects your cat?

Any questions or concerns about toxoplasmosis and its effects on humans should be addressed with your physician.

How Does My Cat Get This?

T. gondii is carried by many animals, but cats are the only definitive host (where the parasite reaches the adult stage and is able to reproduce). Other animals have a specific enzyme that prevents the parasite from maturing.

Infected prey animals, raw meat, and soil can hold tissue cysts called oocysts, which are egg-like structures containing millions of immature T. gondii. When your cat ingests the parasite by eating an already infected animal or picking it up from infected soil, the oocysts transform into developing tissue called tachyzoites. These tachyzoites can pass to different areas of the body, including muscles, the heart, and other organs.

How Will I Know if My Cat Has Toxoplasmosis?

An otherwise healthy cat might not develop or display any signs. Cats with weakened immune systems, pregnant cats, and young kittens are the most susceptible. 

Pregnant cats can pass the parasite to their unborn, resulting in complications that include genetic abnormalities, weak or small kittens, or loss of the pregnancy.

The most common signs a cat with an infection might show include depression, acting tired or listless, or appearing to have muscle or stomach pain. Your cat may have a cough, a fever, stop eating, or have a bloated abdomen, along with vomiting and diarrhea. Eyesight problems or inflammation of the eyes might be present.

As previously stated, the infection caused by the parasite can involve internal organs, and respiratory infections are common.

In a study of cat breeds, Persian, Birman, Ocicat (a domestic breed that has coat markings resembling an ocelot), and Norwegian Forest cats were four to seven times more likely to have positive results when testing for toxoplasmosis.

Both male and female cats can be affected by the parasite.

How Is Toxoplasmosis Diagnosed?

Based on the signs your cat is having, blood work, fecal sample analysis, tissue biopsy, urinalysis, and serum titer tests may be carried out by your veterinarian. More serious cases may require more extensive testing, including radiographs (X-rays) and eye examinations.

What if My Cat is a Hunter But Isn’t Sick?

Although this parasite is common, not all cats will get infected. And even if they do, most healthy cats do not become seriously ill.

After exposure, oocysts can shed for several weeks. A healthy cat can live with the parasite that causes toxoplasmosis for years and you may never know it.

Because the tissue cysts that cause toxoplasmosis are not easily destroyed, the parasite can remain with your cat and become active again in the future, with or without illness. Cats that are otherwise healthy tend to have better outcomes.

How Is It Treated?

Antibiotics will likely be prescribed. If your cat is on any type of immunosuppressive medication, it will most likely be stopped. Supportive therapy and proper medication for any symptoms will be recommended, as appropriate.

Cats can begin to show improvement within 1-2 days of treatment. Depending on the seriousness of a cat’s infection, a full recovery is possible. 

Keeping litterboxes clean, not allowing your cat to hunt in the yard, and not feeding raw diets will help. 

At the time of this writing, studies for vaccinations against toxoplasmosis are not complete, and a vaccination is not yet available.

What are the most common causes of chronic itching?

Itching in cats can involve not only scratching but also chewing, licking and rubbing. The common causes of itching in cats are a type of fungal infection called ringworm, external parasites such as fleas and mange, and allergies.

In itchy cats, we do some culture tests for ringworm, so we can be sure that is not the problem. We often recommend therapeutic trials for mange in chronically and severely itchy cats.  We always recommend stepped-up flea control and monitoring for fleas, as flea infestation can really make allergy worse!

What are allergies?

Allergies are a common cause of skin conditions in cats. People with allergies usually have hay fever (watery eyes, runny nose and sneezing) or asthma. Although cats with asthma can be allergic, most cats with allergies lick or chew their fur.

What are the major types of allergies in cats?

Flea Allergy

Flea allergic dermatitis is the most common skin disease in cats.  For the flea allergic patient, 100% flea control is essential for remaining symptom-free. 

“But doctor, I never see fleas on my pet.”  You may not see them, but that doesn’t mean they aren’t there!  Flea allergy is caused by the flea’s saliva, and it only takes a few bites to cause a problem.  Also, the itchy pet often scratches or licks so much that adult fleas are hard to find because they are removed from the body.

“If fleas are the problem, why is my pet still itchy in the winter?”  In warm climates or in our homes, fleas may survive in low numbers year-round.  Because flea allergy is so common, many veterinarians recommend instituting complete flea control before proceeding with test for itching. For most allergic pets, year-round flea treatment is an important part of reducing itch.

Food Allergy

Some pets develop hypersensitivities to foods. Various food proteins, carbohydrates, or even preservatives or dyes can all be potential food allergens. There is currently no accurate blood or skin test to determine if your cat has a food allergy. The only method of diagnosing a food allergy is by placing your pet on a carefully selected prescription or homemade hypoallergenic diet for several weeks, which is called a food trial. The diet only contains ingredients your pet has never eaten before. If the allergy signs resolve, a food challenge is performed by feeding the former diet and watching for a return of the itching.  If this occurs, a diagnosis of food allergy is confirmed.

Atopic Dermatitis

Atopic dermatitis (AD) is an inherited predisposition to developing skin problems from exposure to a variety of commonplace and otherwise harmless substances including the pollens of weeds, grasses and trees, as well as house dust mites and mold spores.  In cats that have been diagnosed with AD, allergy testing by intradermal skin testing or in vitro blood testing can identify what a pet is allergic to in the environment.  Evaluating the results of these tests helps us compile a list of allergens for a “vaccine” to decrease the pet’s sensitivity. 

Secondary Infections

Allergies are often the underlying cause of recurring skin and/or ear infections.  Bacterial and yeast infections, though secondary to the allergy, can increase your pet’s level of itching.

Can allergies be cured?

Unfortunately, there is no cure for allergy and it is usually a life-long problem. We seek to control allergies and improve the quality of life for both you and your cat.  We will formulate the best program of management that suits all involved with your cat’s care. 

Can itching be treated without the expense of diagnostic testing?

There are many anti-allergy medications to reduce itching.  These medications do not cure allergies but can help decrease the symptoms. However, without addressing the underlying cause of the allergy, the itching will return when the medication is stopped. 

Long-term use of some anti-allergy medications, such as steroids, can result in many health problems.  Working with your veterinarian to diagnose the underlying cause of the allergy and itching may reduce the need for medications or enable your veterinarian to use more specific and targeted allergy treatments.