Gastritis in Dogs

Overview of Canine Gastritis

Gastritis is a general term used to describe inflammation of the lining of the stomach in a dog. The most common sign associated with gastritis is vomiting. Although signs may be mild and self-limiting in some cases, they can be debilitating and even life threatening in others, necessitating hospitalization and intensive supportive care. Acute gastritis is characterized by vomiting of less than 7 days duration. Chronic gastritis is characterized by intermittent vomiting of greater than 1-2 weeks duration. There are a variety of causes of gastritis, some associated with acute vomiting and some associated with chronic vomiting.

Below is an overview of the causes, diagnosis and treatment of gastritis followed by in-depth detailed information about gastritis in dogs.

Causes of Acute Gastritis

• Dietary indiscretion (ingestion of spoiled food, foreign bodies, plant material, hair or overeating)
• Dietary intolerance or allergy
• Ingestion of chemical irritants or toxins (fertilizers, cleaning agents, lead)
• Drugs/medication (aspirin, antibiotics, steroids)
• Infectious agents (viral, bacterial, parasitic)
• Shock or sepsis (systemic infection)

Causes of Chronic Gastritis

• Chronic or long term exposure to, or ingestion of, any of the causes listed for acute gastritis
• Inflammatory bowel disease
• Stomach cancer

There are some systemic diseases that can be associated with both acute and chronic gastritis. Those include kidney failure, liver disease, hypoadrenocorticism, neurologic disease and ulcers. Both dogs and cats can be affected and males just as often as females. Due to the increased potential for dietary indiscretion in younger animals, they are more likely to develop acute gastritis. Chronic gastritis can be seen in all ages.

What to Watch For

• Excessive vomiting
• Excessive vomiting with blood (either red or “coffee-grounds”)
• Lack of appetite
• Weakness
• Weight loss
• Diarrhea
• Melena (black tarry stool representative of digested blood)

Diagnosis of Gastritis in Dogs

Many cases of acute gastritis are short lived, resolve easily, and an extensive diagnostic evaluation is seldom required. Diagnostics should be performed in those individuals whose gastritis is severe, chronic, or are exhibiting systemic signs of illness. A thorough history and physical examination is of paramount importance prior to diagnostic evaluation.

• Complete blood count (CBC), biochemical profile, urinalysis, and fecal examination
• Abdominal radiographs (X-rays) +/- contrast/dye evaluation
• Parvo test on all puppies
• Abdominal ultrasound in selected cases
• Endoscopy in selected cases

Treatment of Gastritis in Dogs

There are several things your veterinarian may recommend to symptomatically treat your dog. The principal goals of symptomatic therapy are to restore and maintain fluid and electrolyte balance, and to completely rest the gastrointestinal tract.

• Nothing orally (NPO) for a several hours, with a gradual introduction of water followed by a bland diet
• Fluid and electrolyte therapy as indicated in the dehydrated patient
• Antiemetics (drugs that symptomatically decrease the frequency of vomiting)
• Antacids (drugs that block acid production by the stomach)
• Gastric protectants (drugs that coat and soothe the GI tract)

Home Care

The primary recommendation is to withhold all food and water until contacting your veterinarian. Administer medication and diet only as directed by your veterinarian and observe your dog very closely. If clinical signs are not improving, and/or your dog is getting worse, have your dog evaluated at once.

In-Depth Information on Gastritis in Dogs

Gastritis is quite common in dogs due to their indiscriminate (not selective) eating habits. It is not uncommon for a normal healthy dog to have occasional bouts of acute gastritis over the course of their life, especially if they are longhaired or have a habit of getting into the trash. As long as they are short lived and self limiting, we tend to consider these “normal abnormalities”. One must differentiate acute from chronic gastritis, as well as gastritis from regurgitation (the backward flow or effortless evacuation of fluid, mucus, or undigested food from the esophagus) as there are different diseases, diagnostics, and treatment plans for each.

In those dogs who are otherwise feeling well, symptomatic therapy, to include removing all food and water for a specified amount of time and gradually reintroducing a bland diet, is generally curative. If the dog continues with signs of gastritis (vomiting, lack of appetite, nausea), despite being held off food and water, or if blood is present in the vomitus, it is important to seek veterinary attention at once. In addition, if your dog seems painful, in distress or sick in any other way, you should contact your veterinarian immediately as diagnostics, hospitalization and supportive therapy may be in order.

There are several disorders/diseases that can cause similar signs and may be confused with gastritis. These include;

• Dietary indiscretion (ingestion of spoiled food, plant material, hair, or overeating) is one of the most common disorders seen in both cats and dogs. Vomiting, diarrhea and flatulence are commonly seen associated with dietary indiscretion.
• Dietary intolerance or allergy to a particular food or substance often is associated with vomiting and/or diarrhea.
• Infectious disorders that affect the gastrointestinal tract including viral, bacterial, fungal and parasitic infections must be differentiated from gastritis.
• Pancreatitis is an inflammation of the pancreas, and in certain cases, can be life-threatening. The most common clinical signs seen with pancreatitis are vomiting and inappetence.
• Metabolic disorders (kidney failure, liver disease, hypoadrenocorticism, diabetes mellitus) are often associated with vomiting, inappetence and weight loss, all of which are signs commonly seen with gastritis.
• Intestinal obstruction/blockage secondary to foreign bodies or tumors must be differentiated from gastritis.
• Infiltrative diseases (microscopic diseases that penetrate and spread throughout) of the gastrointestinal tract including inflammatory bowel disease and lymphosarcoma (cancer) must be ruled out.
• Gastrointestinal ulcers can be associated with liver and kidney disease, pancreatic disease, stress and certain types of cancer. Clinical signs associated with ulcers include vomiting (possibly with blood), melena (black tarry stools due to digested blood), abdominal pain, weakness and potential collapse and death.
• Pyloric hypertrophy is a thickening of the part of the stomach that empties into the small intestine, causing vomiting. It is most commonly seen in small-breed dogs (lhasa apso, shih tzu, Maltese and the miniature poodle.)
• Hemorrhagic gastroenteritis is a syndrome seen in dogs whose cause is unknown. These animals often present with vomiting and bloody diarrhea. Hemorrhagic gastroenteritis is most often seen in urban settings.
• Neurologic disorders, especially of the vestibular (balance and coordination) center will often present for vomiting.
• Certain medications or toxins (such as lead) can cause severe gastrointestinal signs by either directly irritating the lining of the stomach (such as with aspirin administration) or by setting off a reflex mechanism that stimulates the vomiting center of the brain.
• Pain, fear or other psychogenic disturbances can cause gastrointestinal upset, and mimic or cause signs of gastritis.

In-Depth Information on Diagnosis of Canine Gastritis

A tentative diagnosis of acute gastritis is usually made on the basis of history and clinical findings, and no specific diagnostic work up is warranted. If the dog is not responding to symptomatic therapy, and/or the signs are severe, diagnostic tests should be performed. In cases of chronic gastritis, a full diagnostic work up is most always recommended.

• A complete blood count (CBC) will evaluate for the presence of infection, inflammation and anemia, associated with some diseases that cause gastritis.
• A biochemical profile evaluates the kidney, liver, electrolytes, total protein and blood sugar status. All of these parameters are important to establish in the dog with gastritis.
• A urinalysis helps evaluate the kidneys and hydration status of the dog.
• Multiple fecal examinations are important to rule out gastrointestinal parasites as a cause of gastritis.
• A fecal Parvo antigen test should be performed on any young puppy that presents with acute gastritis, regardless of their vaccination history.
• Abdominal radiographs (X-rays) evaluate the abdominal organs (kidneys, liver) and may help visualize the presence of a foreign body or tumor.

Your veterinarian may recommend additional tests to ensure optimal medical care. These are selected on a case-by-case basis.

• An ACTH stimulation test may be recommended to rule out hypoadrenocorticism (Addison’s disease). It is a combination of 2 blood tests that measures adrenal function. It is safe, and can usually be performed at your local veterinary hospital.
• Bile acids are paired blood tests obtained before and after a meal that evaluates liver function. The test is very safe and can be performed at your local veterinary hospital.
• A blood lead level may be indicated in the dog with gastritis, where there has been known or possible lead exposure.
• A gastrin level should be run on any dog with multiple or recurrent ulcers or signs of gastritis. Elevated levels are usually seen in dogs with gastrinoma (a tumor that secretes gastrin, causing ulceration.)
• An upper gastrointestinal (GI) barium (dye) series may be considered in those cases where baseline diagnostics do not confirm a diagnosis, and gastritis persists. It may help diagnose foreign objects or tumors that are not apparent on radiographs, or confirm a diagnosis of GI ulceration. A safe dye is given to the dog by mouth, and is then watched as it travels through the GI tract. It is a non-invasive test that can often be performed by your regular veterinarian, although in some cases may necessitate transfer to a specialty hospital.
• An abdominal ultrasound evaluates the abdominal organs and helps assess for the presence of tumors. Organs, lymph nodes, and masses can be sampled with a needle or biopsy instrument with the guidance of ultrasound. This procedure is relatively safe, however may necessitate a mild sedative. It is often recommended that a specialist perform the procedure.
• Gastroduodenoscopy (upper GI endoscopy) may be of benefit in the dog with gastritis. It may facilitate the removal of foreign bodies, help evaluate for ulcer disease, and sample tissue for the presence of inflammation or cancer. Hospitalization is brief, and healing is generally quick and uneventful. It does, however, necessitate general anesthesia, and therefore is associated with minor risks. It is often necessary to refer the dog to a specialist, and is performed when other diagnostics are either inconclusive or support the diagnosis of a gastric foreign body.
• Lastly, an exploratory laparotomy should be performed as a diagnostic tool in any individual that has had an extensive diagnostic, and sometimes treatment, course with little or no response. It is an invasive procedure but is necessary in a handful of cases for a definitive diagnosis.

In-Depth Information on Treatment of Canine Gastritis

• Withholding food and water for several hours allows the GI tract to “rest”, and is the single most important means of symptomatic therapy for the dog with gastritis. Complete dietary restriction allows the lining of the GI tract to heal. Gradual reintroduction of small amounts of bland food should be instituted after the fast, and the original diet may be slowly reintroduced after 2-3 days if there have been no signs of gastritis. If at any point gastritis recurs, discontinue everything given by mouth and contact your veterinarian.
• Oral medication of any kind should be avoided if at all possible. Any contact with the stomach lining will potentially perpetuate inflammation.
• Fluid and electrolyte therapy may be necessary in some dogs with acute gastritis, and is directed toward correcting dehydration, acid-base, and electrolyte abnormalities. Occasionally, subcutaneous (under the skin) administration may be acceptable, and may be able to be performed at home. In severe cases, intravenous administration may be indicated and necessitates hospitalization.
• Antiemetics (drugs that stop vomiting) should be used with caution. Examples include Reglan® (metoclopramide) or Thorazine® (chlorpromazine). It is best to identify and treat the underlying cause of gastritis, however in selected cases their use may be recommended.
• Antacids (drugs that decrease acid production by the stomach) such as Tagamet® (cimetidine), Pepcid® (famotidine) or Zantac® (ranitidine), may be of benefit in some cases.
• Gastrointestinal protectants and adsorbents (medications that protect or sooth) are felt to coat an “irritated” gastrointestinal lining and bind “noxious” (harmful) agents. Examples include Carafate® (sucralfate) and Pepto-Bismol® (bismuth subsalicylate).
• Antibiotics and parasiticides (medication that kills parasites) are indicated in cases of bacterial or parasite related gastritis.
• Anti-inflammatory agents, such as corticosteroids, may be indicated in cases of documented inflammatory bowel disease.
• Endoscopy or surgery may be indicated to remove foreign objects or tumors causing gastritis.

Follow-up Care of Dogs with Gastritis

Optimal treatment for your dog requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your dog does not rapidly improve. Administer all prescribed medication as directed. Alert your veterinarian if you are experiencing problems treating your dog.

Discontinue/avoid any medication or substance that may be causing or exacerbating (worsening) gastritis. Depending on the underlying cause of gastritis, it may be necessary to return to your veterinarian for reevaluation of certain tests.