Gastroenteritis

The most common cause of gastroenteritis in dogs is due to a food borne illness. Immediate veterinary care is required, as it can be fatal when it not diagnosed and properly managed.

Symptoms

Continuous vomiting and/or diarrhea are the most common symptoms. Hemorrhagic gastroenteritis is identified by blood in the vomit and/or stool. Dogs may become lethargic, listless and exhibit retching.

Anorexia, weight loss, fluid loss and electrolyte imbalance can also occur. Due to dehydration and hemoconcentration, shock may occur due to a decrease in blood plasma volume (hypovolemia).

Causes

Infectious gastroenteritis is caused by pathogens (infectious agents). Some of the pathogens most commonly associated with infectious gastroenteritis include:

• Bacteria (e.g., Campylobacter, Salmonella, E. coli, Clostridia)
• Virus (e.g., Parvovirus, Canine distemper)
• Fungi (e.g., Aspergillus, Penicillium, Fusarium)
• Parasites (e.g., Roundworms, Hookworms, Tapeworms, Whipworms, Coccidia)

E. coli, Salmonella and Corynebacterium are the most significant intestinal pathogens because they can be passed from animal to human or vice versa. Salmonella infections are also important due to association with reproductive disorders.

Sudden dietary changes and/or dietary toxins may cause irritation and/or affect the immune system. Eosinophilic gastroenteritis, a chronic form of the illness, has been associated with allergens in dog foods. Gastroenteritis may be also observed due to irritation caused by stress, toxins, physical obstruction, ulcers, and abdominal disorders.

Gastroenteritis is not specific to any breed or gender, however, small breed dogs are more prone to infectious gastroenteritis.

Diagnosis

It may be difficult to identify the cause of gastroenteritis. Therefore, invasive diagnostic procedures may be required if routine diagnostic procedures are not successful.

A brief outline of diagnostic procedures:

Medical history:

• Physical obstruction, tumors, ulcers, intestinal blockage, etc.
• Information about the severity, progression and magnitude of the vomiting and diarrhea
• The vaccination record may help in ruling out a parvoviral infection

Physical observations:

• A skin test to determine the presence and extent of dehydration
• An abdominal palpation to check abdominal pain and/or abdominal obstruction
• An examination of mucus membranes to determine hemorrhagic losses
• Cardiovascular function provides information on dehydration and/or blood loss
• Visual observation of the vomit and/or stool to determine if there is blood present

Routine blood/biochemical tests:

• Packed cell volume (hematocrit) data to confirm hemorrhagic gastroenteritis
• Biochemical tests (i.e., liver, kidney, blood protein, and blood sugar)

Fecal study:

• Cultural assays to identify any potential microbiological or parasitic organisms

Radiographs/endoscopy:

• To locate any potentinal physical obstruction, tumor, ulcer, intestinal blockage, etc.

Treatment

In most of the cases, dogs recover and respond very well. The course of treatment, however, is dependent on the underlying cause of the condition. A brief outline of treatment is given below:

1. Fluid and electrolyte therapies are important, especially in cases of hemorrhagic gastroenteritis.
2. Antibiotic therapy may be restricted to animals with systemic infections.
3. Corticosteroid therapy is useful in cases of shock. Usually hypovolemic shock develops due to dehydration.
4. Medications that soothe the intestine and bind noxious agents can also be used in supportive therapy.
5. Parasitic infections are treated with anthelmintics.
6. Physical obstruction, ulcers and tumors may need surgical treatment.

Living and Management

An improved diet may reduce intestinal infections and other gastrointestinal disorders. The main priority should be to provide healing time for the dog's inflamed intestinal area. Thus, food and water should not be given for at least a period of 24 hours to rest the intestine. Then, provide a bland diet for three to seven days, followed by a gradual return to the dog's normal diet.

Often dietary irritants (especially protein) may lead to recurrence of the problem. In these cases, a special hypoallergenic medical diet may be required.

Prevention

Some veterinarians have recently emphasized the importance of restoring intestinal microflora through food additives (e.g., probiotics, prebiotics, and synbiotics) in order to prevent the infection from recurring.

If dog owners are using homemade diets, the ideal micro- and macro-nutrient profile, along with optimum energy density, must be the focus of formulation. These diets provide highly digestible nutrients, less fats and restricted osmolarity. Consult your veterinarian for a proper, well-balanced diet for your dog.