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Contact Information.

Natasha Olby Vet MB,PhD, MRCVS, DACVIM (Neurology)
Phone: 919-513-8286

Kim Williams
Spinal Cord Injury Program Coordinator
Phone: 919-513-7235

Back to Canine Spinal Cord Injury Program Home Page



Effect of Cranberry Extract on Myelopathy-Associated Urinary Tract Infections

*Case recruitment is complete and data analysis is ongoing

Funded by the Morris Animal Foundation

Research Purpose

Acute spinal cord injuries are a common problem in dogs, and cause paralysis of the hind legs and of the bladder. In the period following a spinal cord injury, before the bladder regains normal function, dogs are predisposed to developing urinary tract infections. There is evidence that cranberry extract can inhibit the development of urinary tract infections by reducing the ability of certain bacteria to stick to the bladder wall. This study will evaluate whether cranberry extract can reduce the prevalence of urinary tract infections in dogs with spinal cord injuries following disc herniations by comparing dogs treated with a placebo with dogs treated with cranberry extract.

Inclusion Criteria

In order to qualify for the study your dog must have suffered a thoracolumbar spinal cord injury due to a disc herniation that was severe enough to cause the inability to walk, and that was treated with decompressive surgery at North Carolina State University Veterinary Teaching Hospital or Gulf Coast Veterinary Specialists.

Study Protocol

48 hours after your dog has been treated surgically for a disc herniation, it will start to receive cranberry extract or placebo capsules orally once a day. The treatments will look identical and only the pharmacist will know what your dog is receiving. On the day of discharge, and then at 2, 4 and 6 weeks after surgery, we will perform and videotape a neurological examination on your pet, we will walk it on a treadmill for 2 – 5 minutes, and will walk it on a non slip surface (with sling or tail support if needed).  We will also take a urine sample (either by passing a catheter, or by inserting a needle directly into the bladder through the abdominal wall) for a urine culture, and a blood sample from the jugular vein (in the neck) or the cephalic vein (in the front leg). These are routine procedures that we perform on a daily basis in the clinic.

Frequently Asked Questions by Owners

1. What are the benefits of enrolling my dog?

It is possible that cranberry might reduce the incidence of urinary tract infections, and so if your dog receives this treatment, it might have direct benefit. Your dog will also be rechecked three times following surgery, enabling us to closely monitor its progress. All recheck exams, urinalysis, urine cultures and cranberry extract/placebo drugs will be provided at no cost to you.

2. Are there risks for my dog?

Risks are felt to be minimal. Cranberry extract is a safe supplement and is unlikely to cause any problems for your pet. When blood sampling, it is possible that there will be a small amount of bleeding at the site the sample is taken from, causing a bruise or hematoma that should resolve within a few days. When taking a urine sample by introducing a needle through the abdominal wall, there is risk of causing bleeding, and of urine leakage from the bladder. However, the risk is very low – this is a technique that we perform on the majority of dogs that are admitted to the vet school as it is the best way to obtain a urine sample without contaminating it, and we do not see complications from the procedure.

3. What are my responsibilities if I elect to enroll my dog in this study?

This study will last for 6 weeks, during which time you will be asked to bring your dog to the vet school for rechecks 3 times. Each recheck will take approximately 45 minutes. You will also be required to fill out simple questionnaires concerning your dog’s health during each recheck.

Study Contact

Please contact Kim Williams by email or phone 919.513.7235

Principal Investigator:

Natasha Olby, Vet MB, PhD, Dip ACVIM (Neurology) Associate Professor of Neurology/Neurosurgery at North Carolina State University College of Veterinary Medicine.

Co-Principal Investigator:

Shelly Vaden, DVM, PhD Dip ACVIM (Internal Medicine) Professor of Internal Medicine at North Carolina State University College of Veterinary Medicine.

Also participating in this study:

ulf Coast Veterinary Specialists logo

Gulf Coast Veterinary Specialists
1111 West Loop South
Houston, TX 77027
Carley Giovenalla, DVM, DACVIM (Neurology)
Randall C. Longshore, DVM, DACVIM (Neurology)