The attending veterinarian probably will recommend drawing blood to run a complete blood count and a biochemistry panel before performing other diagnostic procedures. While these tests cannot actually be used to diagnose Heliobacter infection, they may help to identify nonspecific changes caused by fluid and electrolyte loss due to vomiting and diarrhea, or other causes of the dog’s discomfort. They also can help rule out other systemic causes of gastric distress. A non-invasive diagnostic tool for Helicobacter infection is the urea breath (or blood) test, which involves giving the dog a radiolabeled-urea test meal and subsequently assessing whether the urea was taken up by Helicobacter bacteria. Unfortunately, this test is not widely available.
Gastric biopsy via endoscopy is the gold standard for definitively diagnosing Helicobacter infection in domestic dogs. This procedure is done with the dog under sedation. The attending veterinarian passes an endoscope through the dog’s mouth and down its esophagus into the stomach. This allows the veterinarian to visualize the inside of the dog’s stomach and to obtain tissue samples (biopsy samples) from different potentially affected areas. These samples will be submitted to a laboratory for assessment on a microscopic level by a veterinary pathologist. Impression smears from the biopsy samples can also be made and are another sensitive and easy test to perform, using various stains to make the bacteria more readily visible microscopically. Another way to obtain diagnostic samples is to enter the stomach surgically through the abdominal cavity. This is called an exploratory laparotomy and is more invasive than obtaining samples endoscopically.
A commercially available rapid urease test can be performed on samples taken endoscopically from the stomach. This is one of the quickest and most accurate tests for Helicobacter and involves putting a biopsy sample from the stomach into a urea broth with phenol red added as a pH indicator. Results can be read in a few hours, and certainly within 24 hours, in the form of a color change in the broth.
Blood samples taken in order to culture Helicobacter are rarely helpful, as the organisms are difficult to culture and the test requires special techniques. Other diagnostic tests include serology and a polymerase chain reaction test (commonly called “PCR”). However, these tests are not widely available.
When a dog is suffering from unexplained bouts of vomiting, diarrhea or other forms of gastrointestinal distress, he should be taken to his local veterinarian promptly. Getting an actual sample of the stomach lining is far and away the most reliable way to confirm active Helicobacter infection. However, vomiting and diarrhea in domestic dogs can be caused by a multitude of things, and only a skilled veterinarian is in the best position to assess the dog and determine the cause of the problem.