This is a disease of the kidneys (from greek, nephros – kidney; opathy- disease or disorder of) with Lyme infection being the underlying cause. Lyme disease is caused by a special type of bacterium, Borrelia burgdorferi. Ixodes-type ticks, like the well-known ‘deer tick,’ spread this organism.
In dogs, Lyme disease tends to be either asymptomatic (most dogs, with 90- 95% showing no clinical signs at the time of diagnosis), or cause a transient fever, lethargy, anorexia and limping. Limping in lyme-infected dogs classically shifts from one leg to the other. It is believed that clinical signs of lyme disease, including limping, is a result of the body’s immune response to the organism. Symptoms usually take a few months from the time of infection to develop.
Most Lyme positive dogs that are clinical for the infection will get better rather quickly on antibiotics, with doxycycline being most veterinarian’s first choice. The infection is usually not cleared, even with treatment, but will usually be kept under control by the dog’s immune system once treated.
A much more serious disease process has been reported, thankfully much more rarely- Lyme Nephropathy. This disease is not completely understood, but it has been found to have an immune basis. The body’s own immune system is needed for the destruction of the kidneys. What happens is the immune system develops antibodies to the organism and these antibodies attach to the organism or pieces of the organism. The antibodies can form immune ‘complexes’ that can attach to regular tissues in the body - one place being the kidneys. This leads to activation of the rest of the immune system, where the body thinks it is clearing an infection and instead damages its own tissues. This process can be likened to laser-guided missile attacks, where the immune complexes are the lasers and the missiles are the immune system components. But in this case, it would be considered ‘friendly fire.’
Dogs with Lyme Nephropathy show signs of anorexia, lethargy, fever and some will even vomit. Kidney levels are often elevated, or elevate later in the course of the disease. The classic hallmark sign of this disease is loss of blood proteins in the urine- called proteinuria. Many will lose enough proteins that their blood work will show low albumin (the major blood protein), leading to leakage of blood fluids from the vessels into the tissues- causing the patient to develop swellings of the tissues called edema.
Most dogs with Lyme Nephropathy have a very poor prognosis, with most succumbing to the disease rather quickly after clinical signs develop despite therapy.
The best way to prevent this infection is to administer monthly tick preventatives to your dog. The topical products, Frontline and Advantix, being the most common and two of the most reliable preventatives on the market. Others are available through veterinary clinics. It is important to follow all the directions and precautions of these products.
The lyme vaccine is controversial at this time, and people seeking this vaccine should speak with their veterinarian at length about its use and benefits/side effects. At the least, every dog receiving this vaccine should first be tested for lyme exposure.
If your dog is exposed to Lyme it is very important to follow your veterinarian’s recommendation. Guidelines recommend routine blood work at the time of diagnosis and at least yearly to check kidney values and other parameters such as white blood cells and platelets. Other tick-borne infections can also be spread by the same ticks that spread Lyme disease and some are more difficult to diagnose on routine screening, but may still cause changes on blood work. Urine should be checked at the time of diagnosis and at least every 6-12 months to check for protein loss. If there is protein in the sample, your veterinarian may want to check for an infection with a urine culture, or for bladder stones using an x-ray of the abdomen. If no other causes of protein in the urine are seen, the level of protein should be quantified with a specific test (called urine protein creatinine ratio, or UPC). This can determine if the protein loss is significant and how severe it is, as well as help guide treatment in the future.
As I first stated, just the sound of this disease makes me cringe…and as I write this blog I think about my patient currently being treated for possible Lyme Nephropathy. I just hope she is not one of the unlucky few, and I hope by following simple preventative measures other dogs can be spared this horrible disease.
Brad Bates, DVM DABVP
Lap of Love Veterinary Hospice
firstname.lastname@example.org | www.lapoflove.com
Dr. Bates services the Greater Philadelphia area with providing families with in home hospice and euthanasia options. (All areas around Philly including Rittenhouse, Center City, Art Museum, Queen village, Washington Square, Graduate Hospital, Society Hill, Italian Market, Logan Square, Bella Vista, Old City, West Philadelphia, South Philadelphia, University City, Fishtown, Northern liberties, Fairmount, Manayunk, Conshohocken, Roxborough, Drexel Hill, Media, Villanova, Swarthmore, New Hope, Langhorne, Bryn Mawr, and Gladwyne).