Entlebucher Urinary Syndrome

Entlebucher Urinary Syndrome (EUS) is a disease of the renal/urinary system caused by an underlying genetic anatomical abnormality at the junction of the ureter and bladder. Clinical presentations can range from no clinical signs, occasional leaking of urine, constant dribbling of urine, all the way to renal failure and death. The most common clinical presentation is slight urine leaking with occasional bladder infections. Treatment can vary depending upon the severity of the abnormalities. For dogs with minimal abnormalities and clinical signs, incontinence medication is the extent of treatment. In some individuals, surgical removal of an affected kidney and ureter is indicated. When critically afflicted individuals are diagnosed early with prompt surgical removal of a kidney and ureter, they can lead long happy lives. Rarely, there are severely afflicted dogs where both kidneys are affected and the prognosis is very poor.

The “silence” of ectopic ureters in Entlebuchers makes it difficult, almost impossible at this time, for breeders to know if their breeding dogs have an increased risk for producing EUS. To know this information, it would be necessary to subject all breeding dogs to costly, invasive, specialist testing. This kind of large-scale screening is so far impossible to do in an ethical manner and would not necessarily eliminate EUS from the Entlebucher population. We just do not yet have the hereditary information needed to differentiate the risk for full-blown EUS from harmless ectopic ureters or complete anatomical normality.

What are the common clinical signs of EUS?

Signs may include:

• abnormal urination patterns such as difficulty with house training or incontinence when sleeping or when fatigued
• frequent urination with large volumes of urine
• a bloated, overly distended abdomen
• failure to thrive
• recurring bladder infections
• sudden repetitive vomiting

What is known about EUS?

EUS appears to be characterized by heritable abnormalities throughout the urinary tract that include some combination of ureteral ectopia, ureteral obstruction, hydroureter, and hydronephrosis (see diagram with definitions). Ureteral ectopia is the most minor of these anatomical abnormalities. It can occur in many breeds and is not life threatening.

In normal dogs, the urine flows from the kidney, down the ureter and into the bladder where the urine is held until the dog urinates. With ectopic ureters, the ureter joins the bladder in an abnormal place, usually in the bladder neck or even farther down in the urethra. In most dogs, this abnormal placement is characterized by incontinence (leaking urine). However, the presentation in Entlebucher dogs is unique. EUS research study, at Michigan State University (MSU), has shown that Entlebuchers can have ectopic ureters and have NO clinical signs. These dogs do not leak or dribble and can produce offspring that do not leak or dribble. Entlebuchers with isolated ectopic ureters typically lead long lives without showing any signs of disease.

However, MSU research has also shown that some of the Entlebuchers with ectopic ureters do leak or dribble. These dogs respond well to medical management with Veterinary prescribed incontinence medication.

Unfortunately, the Entlebucher is also unique in that this abnormality can include not only abnormal ureter placement, but also an abnormality of the physical junction of the ureter. This can lead to a severe case of EUS with abnormal dilation of the ureter and the kidney. When only one side is affected, surgical intervention can be life saving. Often times, in these cases, the affected kidney and ureter need to be surgically removed. Surgically realignment of the other ureter may also be necessary. Very rarely, both ureters and kidneys are affected and the prognosis is grave.

The “silence” of ectopic ureters in Entlebuchers makes it difficult, almost impossible at this time, for breeders to know if their breeding dogs have an increased risk for producing EUS. To know this information, it would be necessary to subject all breeding dogs to costly, invasive, specialist testing. This kind of large-scale screening is so far impossible to do in an ethical manner and would not necessarily eliminate EUS from the Entlebucher population. We just do not yet have the hereditary information needed to differentiate the risk for full-blown EUS from harmless ectopic ureters or complete anatomical normality.

How common is EUS?

All forms of EUS are uncommon with the mildest condition of urine leaking occurring with the most frequency. Fortunately, it is uncommon for Entlebuchers with EUS to have one or both kidneys affected. The precise estimate is not known, but we estimate less than5% of all Entlebuchers in the United States and Canada have been afflicted. Nevertheless, NEMDA breeders continue to monitor carefully for any new puppies with the syndrome.

Which dogs produce puppies with EUS?

While the NEMDA club has been aware of EUS for over 15 years and despite careful selection in breeding pairs, we presently have no means for accurately predicting EUS either symptomatic or asymptomatic within the breed. To our knowledge, there are no breeding lines that can guarantee an EUS-free puppy.

What can NEMDA breeders and puppy owners do?

• Be alert to signs and symptoms of EUS in puppies within the first year or two of life.
• Keep open lines of communication between puppy owners, breeders, Veterinarians, and the chairs of the NEMDA Health & Genetics committee.
• Breeders have EUS leaflets to distribute to their new puppy owners. Puppy owners should ask their Veterinarian to place a copy of this information on the puppy’s chart.
• If a new EUS puppy is suspected or identified, please contact the NEMDA Health & Genetics chair.
• It may be appropriate to ask your local Veterinarian to contact the veterinary researchers at MSU to determine if collaboration could be mutually beneficial. The Health & Genetics Committee chair can help you to do so and provide other support as needed.