Intussusception in Dogs
Intussusception refers to an inflammation of the intestines, a portion of the intestine that has slipped out of its normal place (prolapse), and a portion of the intestine that has folded (invagination). This change in the shape of the intestine can cause the affected portion of the intestine to slip into an adjoining cavity or duct in the body.
While intussusception can occur in animals of all ages, it is more common in younger animals that have weaker immune systems. In affected animals, around 80 percent are younger than one year of age, and in dogs, the affected age tends to be three months or younger. The exact mechanism behind this medical condition is unknown. This obstruction can be either partial or complete, but the occurrence of an intussusception eventually leads to a mechanical obstruction of the gastrointestinal tract.
Symptoms and Types
The clinical signs associated with the intussusception will depend on the anatomic region of the intussusception. If the intussusceptions occur in the gastroesophageal regions -- where the stomach and esophagus are located -- the signs are typically much more severe than if they occur in other regions. Called gastroesophageal intussusception (GEI), this form appears most frequently in the German shepherd dog.
In addition, if there is a total obstruction, the animal will have severe complications potentially and symptoms that are more severe. Whether partial or complete, obstruction of the gastrointestinal (GI) tract can lead to hypovolemia, dehydration, and compromise of the venous and/or lymphatic systems. Prolonged obstruction can lead to necrosis (death of the tissue) and disruption of the normal capacity of the mucosal barrier that protects the GI tract, allowing bacteria and toxins to be absorbed into the GI tract.
Other common symptoms can include:
Intussusception high in the intestinal tract
- Difficulty breathing (dyspnea)
- Bloody vomit (hematemesis)
- Regurgitation (inability to swallow food)
- Abdominal pain
- Abdominal distention
Intussusception low in the intestinal tract
- Bloody diarrhea (melena)
- Occasional vomiting
- Loss of appetite (anorexia)
- Weight loss
- Straining to defecate (tenesmus)
It can be challenging to isolate the exact cause, as any disease that can alter gastrointestinal motility can lead to an intussusception. Some of the most common causes include: enteritis, recent abdominal surgery, intestinal mural disease, intestinal parasites, a foreign object in the tract, and intense contractions of the bowel portion of the intestine.
Your veterinarian will perform a thorough physical exam on your dog, taking into account the background history of symptoms and possible incidents that might have led to this condition. Because there are several possible causes for this condition, your veterinarian will most likely use differential diagnosis. This process is guided by deeper inspection of the apparent outward symptoms, ruling out each of the more common causes until the correct disorder is settled upon and can be treated appropriately.
While some intussusceptions can be chronic in nature, a chronic history of vomiting and/or diarrhea does not necessarily confirm an intussusception. Imaging is often used to properly view the intestines for any possible other causes. This may show an object in the intestinal tract, or a mass of tissue. Your veterinarian may also choose to use a contrasting agent -- a solution that is highlighted in X-ray -- that is either injected or fed to your dog, so that it can be tracked as it progresses through the intestinal tract, allowing your doctor to view any abnormal turns of obstructions.
A fecal sample will be taken to check for intestinal parasites, and the electrolyte balances will be checked. In the case of intussusception that are high in the gastrointestinal tract, electrolyte imbalances, such as hypokalemia, hypochloremia, and hyponatremia are not uncommon.