Questions and Answers
November, 1998
July 24, 1998
RE: Canine Lyme Disease
Dear Dr. Silverio:
I recently read an article that was written by you on “Canine
Lyme Disease” on the Internet. I was hoping that you may be
able to give me some more information regarding this subject.
I have a seven year old spayed female mixed breed dog that we
adopted two years ago from a family that was living in the
southern part of the country. When we received her, she was
underweight and had had a terrible case of fleas for eight
months. We had the fleas taken care of within days and started
her on a good diet.
We have a park near our house where we take her for runs at least
once a day. While we do not have a high rate of lyme ticks in our
area, she does run in the woods. She was also only on a flea
prevention medicine - not one with tick prevention.
About five months ago, she started to develop a slight limp in
one of her front legs. We thought she may have strained her leg,
however, it became increasingly worse over the next two months
accompanied by lethargy and eventually she did not want to go to
anyone.
She had x-rays taken and hip dysplacia and arthritis were ruled
out. Our vet took blood which came back negative for lyme and
canine “AIDS” but decided to treat her for lyme with
doxycycline. She was on it for three weeks and while it did help
with the lethargy and “depression” she still limps when
she first gets up.
Does this sound like it can be lyme disease? Any information you
can provide will be of great help. Thank you very much.
Dear Susan,
Like any other laboratory test, the methods available for testing
for Lyme Disease antibodies have imperfections. The Western Blot
test is probably the most specific, but false negative results
occur and are most commonly seen when the test is run too soon
after infection, probably the first few weeks.
The progressive nature of your dog’s disease, including
lethargy and depression (and multiple joints or legs?) makes us
suspicious of a systemic problem such as Lyme or autoimmune
disease. Autoimmune disease, occasionally referred to using the
initials AID, is caused by an overly-active immune system which
damages the body’s normal healthy tissues. With diseases
like Systemic Lupus, signs can involve joints, skin and internal
organs, such as the kidneys. Autoimmune diseases are usually
treated with long-term corticosteroids (see March 1998 SPO
Magazine). False-negative blood tests are common, but diagnosis
can be made by biopsy of affected tissues or response to
treatment.
If your dog’s response to antibiotic treatment was very
dramatic, then autoimmune disease is unlikely and infection (Lyme
or other bacterial) is more suspicious. Chronic bacterial
infection of bones or joints is occasionally seen, is usually
preceded by a skin-penetrating injury and would probably involve
a single bite. Infection of bone would eventually show up on
X-rays and infection of joints usually displays warm, swollen
joints.
Your next step, then, probably depends on the severity of the dog’s
condition now and on some facts not mentioned in your letter. If
she shows only some stiffness when getting up, then cortisone or
non-steroidal anti-inflammatory drugs such as aspirin or
carprofen (Rimadyl) may be all that she needs. If she is not
doing well now, your options would include some invasive
diagnosicts, such as a joint tap or biopsy, or medications, such
as additional antibiotics or an immunosuppresive dose of
corticosteroids.