Lyme Borreliosis in Cats
Even though it is uncommon in cats, lyme disease is known to be one of the most common tick-transmitted diseases in the world. Caused by a bacteria spirochete species of the Borrelia burgdorferi group, its dominant clinical feature in cats is lameness due to inflammation of the joints, lack of appetite, and lethargy. Some cats develop kidney conditions, and rarely heart or nervous system diseases.
Symptoms and Types
Many cats with lyme disease do not exhibit any symptoms. Those that do may have recurrent lameness of the limbs due to inflammation of the joints. Others, meanwhile, may develop acute lameness, which lasts for only three to four days but recurs days to weeks later, with lameness in the same leg, or in other legs. Better known as “shifting-leg lameness,” this condition is characterized by lameness in one leg, with a return to normal function, and another leg is then involved; one or more joints may be swollen and warm; a pain response is elicited by feeling the joint; responds well to antibiotic treatment.
Some cats may also develop kidney problems. If left untreated, it may lead to glomerulonephritis, which causes inflammation and accompanying dysfunction of the kidney's glomeruli (essentially, a blood filter). Eventually, total kidney failure sets in and the cat begins to exhibit such signs as vomiting, diarrhea, lack of appetite, weight loss, increased urination and thirst, fluid buildup in the abdomen and fluid buildup in the tissues, especially the legs and under the skin.
Other symptoms associated with lyme disease include:
- Stiff walk with an arched back
- Sensitive to touch
- Difficulty breathing
- Fever, lack of appetite, and depression may accompany inflammation of the joints
- Superficial lymph nodes close to the site of the infecting tick bite may be swollen
- Heart abnormalities are reported, but rare; they include complete heart block
- Nervous system complications (rare)
Borrelia burgdorferi, which is the bacteria responsible for lyme disease, is transmitted by slow-feeding, hard-shelled deer ticks. However, infection typically occurs after the Borrelia-carrying tick has been attached to the cat for at least 18 hours.
You will need to give a thorough history of your cat's health, including a background history of symptoms, and possible incidents that might have precipitated this condition, such as the areas in which your cat might have been. The history you provide may give your veterinarian clues as to which organs are being affected secondarily. A complete blood profile will be conducted, including a chemical blood profile, a complete blood count, and a urinalysis. Your veterinarian will use these tests to look for the presence of bacteria, parasites, and fungi in the bloodstream. Fluid from the affected joints may also be drawn for analysis.
The condition of the skin near the tick-bite site will be an important indicator of your cat's health as well, such as whether the wound is still open, or whether there are any fragments of the tick's body left in the wound.
There are many causes for arthritis, and your veterinarian will focus on differentiating arthritis initiated by Lyme disease from other inflammatory arthritic disorders, such as trauma. Immune-mediated diseases will also be considered as a possible cause of the symptoms, and an x-ray of the painful joints will allow your doctor to examine the bones for damage or disorder.
If the diagnosis is Lyme disease, your cat will be treated on an outpatient basis, unless its health condition is severe. There are a number of antibiotics from which to choose. It is important that you keep your cat warm and dry, and you will need to control its activity until the clinical signs have improved. The recommended period for treatment is four weeks. Your veterinarian is unlikely to recommend dietary changes. Do not use pain medications unless they have been recommended by your veterinarian.
Unfortunately, symptoms do not always completely resolve in some animals. In fact, long-term joint pain may continue even after the bacteria has been fully eradicated from your cat's system.
Living and Management
Improvement in sudden (acute) inflammation of the joints caused by Borrelia should be seen within three to five days of antibiotic treatment. If there is no improvement within three to five days, your veterinarian will want to consider a different diagnosis.
If possible, avoid allowing your cat to roam in tick-infested environments where Lyme borreliosis is common. In addition to grooming your cat daily and removing ticks by hand, your veterinarian can recommend a variety of sprays, collars, and spot-on topical products to kill and repel ticks. Such products should only be used under a veterinarian's supervision and only according to the label's directions.
- Mechanical removal of ticks – groom your cat daily; discuss appropriate techniques for the removal of ticks with your veterinarian
- Prevention of tick attachment – sprays and collars, products used to kill ticks and tick repellents are available commercially as spot-on topical products; such product should be used only according to label directions
- Control the tick population in your environment if your cat is restricted to small areas; you may have limited success by reducing deer and/or rodent population