Renal dysplasia is a developmental kidney disorder that affects dogs, usually appearing in puppies or young adults. It occurs when the kidneys don’t form properly before birth, leaving them with abnormal or immature tissue that can't function as well as healthy kidneys. Because the kidneys are responsible for filtering waste and maintaining fluid balance, this condition can lead to serious health problems as the dog grows.
The exact cause of renal dysplasia isn’t always clear, but genetics often plays a role, meaning certain breeds are more at risk. Breeders can help reduce the chances of passing on the condition by screening for it and avoiding breeding affected dogs.
Since renal dysplasia is present at birth, most dogs do not show signs of illness. Over time, they may start to show signs like increased thirst and frequent urination. As more time passes, they may start to show more obvious signs of illness including poor appetite, weight loss, low energy, or vomiting.
Sometimes the symptoms don’t appear until the disease has progressed significantly. The severity of the condition can vary—some dogs may live for years with mild signs, while others may develop kidney failure early in life. Unfortunately, there is no cure, but early diagnosis and supportive care can improve a dog’s quality of life.
Diagnosis of renal dysplasia can be challenging. Suspicion for renal dysplasia first arises when routine lab work, often done prior to spaying or neutering, shows increased kidney values (specifically creatinine or SDMA). Persistently increased kidney values are always abnormal, especially in puppies or young adults. Another sign can be excessive thirst and urination, resulting in difficulty with house training.
An abdominal ultrasound is often recommended to more directly look at the kidneys, but the findings can be variable. Sometimes the kidneys can look misshapen, irregular, small, or have degenerative changes that are inappropriate in a young dog. Other times they can look normal, because the abnormalities that affect the kidney function are microscopic.
A definitive diagnosis of renal dysplasia requires a kidney biopsy, but this is rarely done. In most cases a presumptive diagnosis is made if other causes of increased kidney values are ruled out.
Renal dysplasia cannot be reversed and affected dogs will have progressive deterioration in their kidney function. The rate of progression is unique for each individual and can’t be accurately predicted.
The most common treatment is a prescription diet which helps to reduce the metabolic workload of the kidneys. These diets are low in sodium and phosphorous and often supplemented with potassium and omega-3 fatty acids. Other complications of renal dysplasia can include high blood pressure or high levels of protein in the urine, requiring additional treatments. Dogs that are more severely affected can have trouble drinking enough to stay hydrated and require additional fluid therapy (often given under the skin).
The goal of treatment is to help manage symptoms and support the dog’s kidney function for as long as possible.