Intussusception calls for exploratory laparotomy

Signalment:

Canine, Golden Retriever, 6 months old, male, 46 lbs.

Clinical history:

The puppy first presented three weeks ago for intermittent diarrhea, weight loss and being very thin. The puppy was eating acceptably. The puppy was treated with metronidazole, Albon, bland food, Drontal, Rimadyl and amoxicillin. The puppy presented last night for worsening diarrhea, vomiting, and not eating. The puppy was admitted for intravenous fluids and radiographs.

Image 1 and Image 2.

Physical examination:

The findings include rectal temperature 102.8° F, heart rate 160/min, slightly pale mucous membranes and normal capillary refill time. Normal heart and lung sounds are heard. The puppy is quiet, alert and responsive, and is extremely thin, wasting muscle mass, fluid-filled abdomen and segment of thickened bowel.

Laboratory results:

A complete blood count, serum chemistry profile, and urinalysis were performed and are outlined in Table 1.

Table 1: Results of laboratory tests

Radiograph examination:

The thoracic radiographs are normal. The abdominal radiographs show multiple gas-distended loops of bowel and fluid filled abdomen.

Ultrasound examination:

Thorough abdominal and right ocular ultrasonography was performed.

My comments:

There is a small amount of free fluid accumulated within the abdominal cavity. The liver and gall bladder are not seen. The spleen shows a uniform echogenicity in its parenchyma - no masses noted. The left and right kidneys are similar in size, shape and echotexture. No masses or calculi were noted in either kidney. The urinary bladder is distended with urine and contains some urine sediment material - no masses or calculi noted. There are what appears to be bowel loops seen inside bowel loops.

Image 3 and Image 4.

Case management:

In this case, most likely intussusception or lodged foreign body with intestinal obstruction is the clinical diagnosis. No matter what, an exploratory laparotomy needs to be done. It is possible that these latest signs shown by this puppy have just happened in the last 24 hours.

Review of intussusception

An intussusception is a telescoping of one segment of the intestinal tract into an adjoining segment of intestinal tract. Intussusceptions are seen in all dog breeds. It is seen in all age animals, but it is more common in young dogs, with the exception of intussusceptions secondary to tumors, which are more common in older dogs.

Intussusceptions generally occur as a secondary problem to some disorder or disease that causes increased intestinal mobility or inflammation. There are times when intussusceptions occur for no apparent reason, so it is likely that primary intussusception can occur. Many disorders can cause intussusceptions, and many other diseases/disorders have the same signs. These include:

Image 5 and Image 6.

• Viral enteritis, specifically canine parvovirus enteritis, can either contribute to the formation of an intussusception, or mimic its clinical picture. The most common signs associated with canine parvovirus enteritis are vomiting, diarrhea (often with blood), inappetence and dehydration.

• Bacterial enteritis, inflammation/infection of the intestinal tract with Salmonella, Clostridium and other bacterial species, is commonly associated with signs similar to those associated with intussusceptions.

• Chronic parasite infection, such as roundworms, hookworms and whipworms, may contribute to the formation of an intussusception or cause similar signs.

• Gastrointestinal foreign bodies, due to their ability to cause irritation and an obstruction, often present for similar signs.

• Hemorrhagic gastroenteritis (HGE) in dogs is characterized by the acute (sudden) onset of bloody diarrhea, usually explosive, accompanied by high packed cell volumes.

• Mesenteric volvulus is seen in dogs (most commonly, German Shepherds), where the tissue that connects abdominal organs to the body wall twists upon itself, causing severe and devastating clinical illness and death.

• Gastroesophageal intussusception is when the stomach slides up through the esophagus, causing signs that need to be differentiated from an intussusception lower in the intestinal tract.

• Gastrointestinal masses (tumors) can cause an obstruction of the intestinal tract either due to their physical presence or by predisposing the animal to an intussusception.

• Hypoadrenocorticism may cause signs similar to those with a partial intussusception, such as vomiting, diarrhea, weakness and collapse.

• Animals with other metabolic disorders, such as kidney failure or liver disease, may have vomiting, diarrhea and a host of gastrointestinal signs that initially may need to be ruled out.

• Pancreatitis often has a combination of vomiting, inappetence and/or bloody diarrhea.

Intussusceptions can occur anywhere throughout the gastrointestinal tract, and depending on their location, the type and degree of clinical signs may vary.

Intussusception occurs when a segment of intestine overrides another segment, trapping it inside in a telescoping effect. This cuts off the circulation to the sucked up segment of intestine and it dies if the situation is not relieved. The dead segment of intestine then leads to the death of the affected dog as infection and shock occur.

Image 7 and Image 8.

In general, when the blockage is high in the gastrointestinal tract, the signs are often most severe and life threatening. Some signs may include vomiting, vomiting blood, anorexia, depression, bloody diarrhea and abdominal pain. Signs may progress rapidly and become severe within a few hours. Signs of shock, collapse and sudden death do occur. Intussusception can sometimes be chronic. It can also be a "come and go" problem.

Intussusceptions occasionally may resolve on their own and then recur. It is possible to remove an intussusception surgically, put the remaining intestinal ends back together, and watch a new intussusception form right at the same site.

Image 9.

Diagnostic considerations

Diagnosis may include:

• A complete blood count (CBC), serum chemistry profile, urinalysis and fecal examination.

• Thoracic and abdominal radiographs to eliminate a foreign body or other disease process.

• Abdominal ultrasound study

• Upper gastrointestinal contrast study

• Endoscopy of the gastrointestinal tract.

Abdominal ultrasonography is an accurate method for the diagnosis of intestinal intussusception in dogs. The ultrasonographic appearance of intussusception varies. The target-like mass with hyperechoic or anechoic core surrounded by concentric rings in transverse segments and hyperechoic and hypoechoic parallel lines. Tumor-like or kidney-like mass and trident-like configuration in longitudinal segments is seen.

Aggressive treatment

Treatment of dogs with an intussusception should include hospitalization and aggressive treatment, as clinical deterioration is often rapid and can be fatal. Most of these cases are surgical emergencies. Aggressive fluid and electrolyte therapy is extremely important. Antibiotics are usually prescribed and the veterinarian should also recommend a specific post-operative diet.

The prognosis for dogs with an intussusception is variable, depending on the severity and degree of the intussusception and the associated clinical signs seen in the dog. Routine veterinary care will eliminate many predisposing factors, although many cases cannot be prevented. If the dog has a recurrence of signs, most often seen within the first week of surgery, the owner should contact the veterinarian at once.

Dr. Hoskins is owner of DocuTech Services. He can be reached at (225) 955-3252; fax: (214) 242-2200.