Lyme Nephritis

Lyme nephritis is a form of kidney inflammation that can develop in dogs who have been infected with Borrelia burgdorferi, the bacterium transmitted by certain ticks. The condition arises when the immune response to the infection appears to affect the kidneys' filtering units, sometimes progressing quickly. It is seen most often in Labrador Retrievers and Golden Retrievers, though other breeds can be affected. Owners often notice a sudden change in thirst and urination, reduced appetite, lethargy, or weight loss. Some dogs may have had known tick exposure or a previous Lyme disease diagnosis, while in others the kidney signs appear without an obvious prior history. The presentation can range from subtle changes in drinking habits to more pronounced illness over the course of days to weeks. This page explores the patterns that may prompt investigation, what is understood about the immune and kidney mechanisms involved, how the condition is identified through blood work and urine testing, and the range of approaches used to support kidney function and manage the underlying process.