Lyme disease was first described in dogs in 1984. It is seen
throughout the active tick season, but is most often diagnosed
in dogs in late spring and fall, rather than during midsummer.
Acute Lyme disease:
Acute LD in dogs typically presents with an abrupt onset of
fever, anorexia, moderate to severe lethargy and lameness.
- True "polyarthropathy" is rare; more commonly
single or bilateral joints are affected.
- The lameness may be shifting and may or may not be accompanied
by swollen joints (esp. carpal or tarsal joints).(Click here for a photo of carpal
swelling in a dog with LD)
- When specifically affected joints can be identified, they
are often acutely sensitive to flexion.
- Lymphadenopathy may be present, but this is not always a
consistent or prominent finding.
Chronic Lyme disease:
The role of B. burgdorferi in chronic arthritis, cardiac
and neurologic disease in dogs is much less definitive than in
humans.
- Dogs may present with chronic, intermittent, non-erosive
arthritis, and there are reports of erosive, rheumatoid arthritis
secondary to B. burgdorferi infection.
- Conduction disturbances, endocarditis, pericarditis and various
neurologic abnormalities, including behavioral changes and seizures,
have been seen in LD seropositive dogs.
- A protein-losing nephropathy with membranoproliferative glomerulonephritis,
tubular necrosis and interstitial nephritis has been seen in
several LD seropositive dogs.
- However, with only serologic evidence of LD in most of these
cases, one cannot assign a specific cause-and-effect relationship
to B. burgdorferi infection.
In utero transmission
of B. burgdorferi in dogs?:
There is limited evidence for in utero transmission
of B. burgdorferi in dogs. In one study, bitches were experimentally
infected prior to and during gestation. Puppies born to 8/10 inoculated
bitches were PCR (+) for infection and 2/10 were culture (+).
- These results are of interest because there are at least
7 documented cases of adverse fetal outcomes in women who were
infected during pregnancy.
