Though the most common symptom of Lyme disease in dogs is lameness caused by joint pain and swelling, veterinarians are also recognizing a form of the disease referred to as Lyme nephritis. This is a form of Lyme disease which causes damage to the kidney of the dog and results in kidney failure and eventually death.
Symptoms of Canine Lyme Disease Nephritis
Lyme disease nephritis symptoms are those of renal failure and may consist of:
- Not eating
- Weight loss
- Increased water consumption
- Increased urine volume
- Swelling of legs
Other milder symptoms of Lyme disease may have been noticed previously. The dog may have shown evidence of lameness, fever and/or general malaise. It is possible that the dog may been a chronic carrier of Lyme disease.
Diagnosis of Canine Lyme Disease Nephritis
Diagnosing nephritis caused by Lyme disease is based on identifying a positive Lyme disease antibody test using either a Idexx SNAP 3DX or 4DX or a quantitative C6 antibody level along with evidence of renal involvement.
Determining renal involvement involves blood tests (complete blood count, serum chemistry blood profile) and urine tests (urinalysis, protein:creatinine ratio).
- Blood tests should reveal elevated BUN and creatinine values, indicating that kidneys are not functioning within their normal limits.
- Blood tests will also likely reveal decreased protein levels due to protein loss through the kidneys.
- Urine tests should reveal protein in the urine, resulting from abnormal amounts of protein passing through the kidneys and ending up in the urine.
- Urine tests will also likely reveal a low specific gravity, indicating that urine is dilute because the kidneys are not able to work properly and create a concentrated urine.
Once it has been determined that both a positive Lyme disease antibody test and renal involvement is present, the next step is ruling out other causes of renal disease. A positive Lyme antibody titer or test does not automatically lead to a diagnosis of Lyme disease nephritis. Other tests which may need to be done include:
- abdominal radiographs
- abdominal ultrasonography
- biopsies of the kidney
Treatment of Canine Lyme Disease Nephritis
Treatment for Lyme disease nephritis in dogs is aimed at improving the function of the kidneys. Potential treatments may include:
- intravenous fluids
- feeding a “kidney diet” with restricted phosphorus, salt and protein levels
- phosphorus binders, such as aluminum hydroxide
- antibiotics, including doxycycline
- ACE inhibitors, such as enalapril or benazapril
- gastrotomy or PEG tube to provide nutrition if not eating
- kidney dialysis
Prognosis for Canine Lyme Disease Nephritis
The prognosis for dogs suffering from nephritis caused by Lyme disease is poor. Usually the disease is fatal at this stage.