IndeVets work in more than 200 client hospitals from New York to Virginia, so we are very familiar with tick-borne diseases. Working in so many hospitals, we get to see different protocols for tick-borne disease testing and treatment. Because of the disparity in protocols, we recently discussed current standards for the most common tick-borne diseases we see and reviewed important points made in the ACVIM’s 2018 consensus update for Lyme Borreliosis in dogs. Our review focused on those dogs that tested positive but were asymptomatic for the disease.
Anaplasma, carried by the ixodes and brown dog ticks, and Erhlichia, carried by the lone star and brown dog ticks are two diseases that our dog patients are commonly exposed to in the Northeast. Dogs that are symptomatic for these diseases in the acute stage can show lethargy, inappetence, fever, lameness and changes to their complete blood count (usually thrombocytopenia). Usually, though, dogs have no clinical signs of disease and we are only alerted to their exposure when they test positive on routine annual screening tests.
The screening tests we are most familiar with are performed in the veterinary hospital, test for antibodies to the disease and have the most reliable results four weeks after exposure. At the least, our doctors educate their clients on appropriate tick preventatives and recommend a complete blood count to check for changes caused by the offending organism.
However, each case is different and may warrant a more thorough work-up and treatment plan.
Testing and treatment for asymptomatic, Lyme borreliosis-positive dogs is more controversial right now. Last year, a consensus statement was released by the American College of Veterinary Internal Medicine (ACVIM) reviewing the disease, its diagnosis and treatment. The bad news is there still isn’t a true consensus as to how and when to test and treat positive, asymptomatic dogs and each veterinary hospital has a slightly different process for when a dog is positive on an annual screening test.
Of course, the entire dog must be taken into consideration when recommending additional diagnostics and treatment. When an asymptomatic dog is positive for Lyme disease, our bare minimum recommendations include a urinalysis with a urine protein-creatinine (UPC) ratio (preferably from a sterile urine sample), client education on tick-borne diseases and their prevention and a discussion on starting the Lyme vaccination. If the dog isn’t proteinuric, two-thirds of the internists on the consensus statement do not recommend treating those dogs with doxycycline.
If the dog is proteinuric, further diagnostics such as a full chemistry screen, CBC, and a C6 level may be considered prior to starting treatment. Treatment should be initiated for at least 4 weeks and a UPC would ideally be repeated in 3-6 months. Some veterinarians also recommend rechecking a C6 level in six months to confirm the level has fallen, but there is no consensus on this either.
Although tick disease is very common and diagnosis and treatment is still controversial, the one aspect that we can all agree on is client communication – let’s talk about ticks and preventing the diseases they carry!
Dr. Brunetti is Chief Medical Officer for IndeVets.