The Shih Tzu and Renal Dysplasia

Hard to detect and difficult to treat, Renal Dysplasia is a genetic defect of the kidneys that is always irreversible and that affects Shih Tzus more than any other breed. Identifying the disease is challenging because it is often slow to develop, sometimes not showing symptoms for several years. Mildly affected dogs can live a normal life, virtually symptom-free, quietly passing the disease down to the next generation. More severely affected dogs will have a shortened life due to progressive kidney failure.

Knowing the signs of Renal Dysplasia

This inherited disease causes the kidneys of Shih Tzus to develop abnormally from birth. Because of this affliction, nephrons—the urine-forming units in the kidney—remain immature and function inefficiently throughout the dog's life. Dogs with Renal Dysplasia also have a reduced number of glomeruli, the structures that filter toxins from the blood. In combination, these abnormalities compromise the Shih Tzu's kidney function and ability to cleanse its system and evacuate properly.

In the first stage of Renal Dysplasia, there is a silent and progressive decrease in kidney function over months, or even years. During stage two, the kidneys are working at about 30% efficiency and symptoms become obvious: Excessive thirst, high volume of pale urine, loss of weight, low energy. If you have a severely affected puppy you may notice excessive drinking after only eight weeks of age. Normal Shih Tzu pups can drink as much as five times the normal amount, considered one ounce of water per pound of body weight. Stage two can also last from months to several years.

At stage three, vomiting, further weakness and severe debilitation indicate renal failure. Stage three generally lasts no longer than a month or two before resulting in death.

Genetic testing may finally stop this deadly disease

While there is no cure for Renal Dysplasia, prevention may come in as little as two years in the form of a genetic test for the disease.

The American Shih Tzu Club is at the forefront of research to identify a genetic marker for Renal Dysplasia. If that succeeds, veterinarians and breeders will be able to easily identify even asymptomatic Renal Dysplasia in Shih Tzus with a simple cheek swab. Once the marker is located, the afflicted dog will be prevented from breeding, thus removing the inherited disease from the gene pool.

Identifying a genetic marker could eventually mean the elimination of Renal Dysplasia in Shih Tzus, creating a healthier, happier breed.