SECTION 5 Digestive System

Section Editor: Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

Anal Sac Diseases

Cholangiohepatitis in Cats

Cleft Palate

Colitis, Acute

Colitis, Chronic

Copper Storage Hepatopathy in Dogs

Epulis in Dogs

Esophageal Foreign Body

Esophagitis and Esophageal Stricture

Exocrine Pancreatic Insufficiency

Fecal Incontinence

Gall Bladder Disease in Dogs

Gastric Dilatation-Volvulus

Gastrointestinal Ulceration

Gingivitis

Hemorrhagic Gastroenteritis in Dogs

Hepatic Encephalopathy

Hepatic Lipidosis in Cats

Hepatitis in Dogs, Chronic

Inflammatory Bowel Disease in Cats

Inflammatory Bowel Disease in Dogs

Intestinal Neoplasia

Intestinal Obstruction

Intestinal Parasites

Lymphoplasmacytic Stomatitis in Cats

Megacolon in Cats

Megaesophagus

Oral Melanoma in Dogs

Oral Squamous Cell Carcinoma in Cats

Pancreatitis in Cats

Pancreatitis in Dogs

Perianal Fistula in Dogs

Perianal Tumors

Perineal Hernia in Dogs

Portosystemic Vascular Anomalies

Protein-Losing Enteropathy

Salivary Mucocele in Dogs

Anal Sac Diseases

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

TREATMENT AND FOLLOW-UP

Treatment Options

Uncomplicated impaction of the anal sacs can often be treated by manually expressing the sacs. After the sac is emptied, clinical signs usually disappear rapidly. Prevention of further impactions can be attempted by increasing fiber in the diet and ensuring that your pet has frequent opportunities to defecate.

Animals with infected anal sacs often need broad-spectrum antibiotics and manual expression of the sacs. In severe cases, surgical drainage of the abscessed gland may be needed. Surgical removal of the sacs may be recommended in animals with recurring impactions or infections. Cancer of the anal glands is treated by surgical removal of the tumor. Anal gland cancer can be very aggressive and can invade the lymph nodes of the abdomen, so referral to a veterinary oncologist may be recommended.

Follow-up Care

Most cases of impactions resolve with therapy and do not require frequent follow-up visits. Notify your veterinarian if any signs recur. Dogs with infected or abscessed anal glands are often re-examined after 1 week of antibiotic therapy. If any clinical signs worsen, if the animal’s appetite decreases, or if new signs appear (such as a foul odor or pus near the anus), seek further veterinary care for your pet.

Prognosis

Prognosis for most dogs and cats with anal sac impaction is good, because most cases are easily managed with manual expression and dietary change. Dogs with infected or abscessed anal glands have a less certain prognosis, depending on the severity and depth of the infection. Dogs with anal gland tumors have a poor or grave prognosis, because these tumors often have spread to other parts of the body by the time they are detected.

SPECIAL INSTRUCTIONS:

Cholangiohepatitis in Cats

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

One of the most important functions of the liver is the synthesis and release of a substance called bile, which is released into the small intestine to help digest fats. The importance of bile flow has been known for so long that our names for the parts of the liver that secrete and release bile are based on the medieval word for bile, choler. Cholangiohepatitis is inflammation of the vessels (cholangio) that carry bile through the liver, called the biliary tree, and of the liver itself (hepatitis). Cholangiohepatitis begins with inflammation of the biliary tree, and the liver becomes inflamed later in the disease.

Causes

Two major forms of cholangiohepatitis exist in cats. These two forms differ in the type of inflammation present and in their cause. In younger cats, the major form is suppurative cholangiohepatitis, which usually involves a bacterial infection of the bile system or liver. In older cats (usually older than 8 years of age), lymphocytic cholangiohepatitis is more commonly diagnosed. The cause of lymphocytic cholangiohepatitis is not well known, but it may arise from an abnormal reaction by the cat’s own immune system (immune-mediated inflammation) to the liver and bile ducts.

Cholangiohepatitis is often diagnosed in association with inflammatory bowel disease (IBD) and pancreatitis. When all three problems are present together, the condition is called feline triaditis.

Clinical Signs

Clinical signs are often vague and variable. Probably the most common clinical sign is a decreased or absent appetite. Vomiting, jaundice (yellow color to the gums, whites of the eyes, or skin), weight loss, and fever may also be noted. In some cats loss of appetite is the only sign, and the diagnosis is not suspected until diagnostic tests have been run. Signs of IBD and pancreatitis may also be present. (See also the handouts on Inflammatory Bowel Disease in Cats and Pancreatitis in Cats.)

Diagnostic Tests

Diagnosis of cholangiohepatitis usually requires several different diagnostic tests. Blood tests typically show increased liver enzyme activities and often an elevated bilirubin, which is the chemical that causes the yellow color of jaundice. An abdominal ultrasound is often recommended to examine the liver, biliary tree, and gall bladder, which may be thickened or distorted. Samples of bile may be obtained for bacterial culture, and in some situations parts of the liver may be biopsied and cultured.

Because the treatment for suppurative cholangiohepatitis is different from that for lymphocytic cholangiohepatitis, biopsy of the liver can be extremely important in determining appropriate treatment. Other laboratory tests and x-rays may be recommended to rule out diseases that cause similar clinical signs.

TREATMENT AND FOLLOW-UP

Treatment Options

The main treatment for suppurative cholangiohepatitis is long-term (2-6 months) antibiotic therapy. Ideally, the antibiotic is chosen based on results of a bile or liver culture. If lymphocytic cholangitis is diagnosed, the main treatment is anti-inflammatory or immune suppressive doses of glucocorticoid drugs, such as prednisone.

Additional treatments may be recommended to help improve liver function and protect against further damage. These treatments may include antioxidant medications (such as SAMe or vitamin E), multiple vitamin supplements, appetite stimulants (such as mirtazapine or cyproheptadine), and drugs (such as ursodiol) that make the bile more watery so that it can be secreted more easily. All of these supportive treatments may make the cat feel better sooner, but they do not fix the underlying problem on their own.

Some extremely sick cats require hospitalization for fluids, intravenous antibiotics, and assisted feeding. Cats with cholangiohepatitis are at risk for developing hepatic lipidosis (fatty liver syndrome), particularly if they are overweight and stop eating completely. (See also the handout on Hepatic Lipidosis in Cats.)

Follow-up Care

Cat with cholangiohepatitis need regular follow-up visits to check their progress. Initially, progress checks may be recommended every 7-14 days; later, they may be decreased to once monthly, depending on the cat’s response to the therapy. At the follow-up visits, blood samples are often drawn to recheck the liver tests, bilirubin levels, and other abnormalities.

Prognosis

Prognosis for cats with cholangiohepatitis is variable, depending on the type (suppurative or lymphocytic), the presence of other diseases (IBD, pancreatitis), and the willingness of the cat to take medications. Most cats with cholangiohepatitis can be successfully treated, but some cats die of this condition, particularly if they develop hepatic lipidosis.

SPECIAL INSTRUCTIONS:

Cleft Palate

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

A cleft palate is a gap or hole in the roof of the mouth. The palate originally forms as two halves, on the left and right sides of the mouth. These two halves normally fuse during the development of the fetus. A cleft palate results when the two sides of the palate do not fuse properly prior to birth. The palate has a hard, bony part (hard palate) and a soft, membranous part (soft palate). A cleft may involve either or both of these parts. Clefts of the front part of the hard palate may also involve the upper lip. Cleft palates are more common in dogs than in cats.

Causes

A cleft sometimes forms in the palate after trauma to the head and mouth, such as being hit by a car. More commonly, a cleft palate is a congenital birth defect. Some drugs (steroids, hydroxyurea) are known to increase the risk of cleft palate in puppies if they are given to the mother early in pregnancy. Some dog breeds, particularly the brachycephalic breeds (breeds with flat faces, such as the Boston terrier, English bulldog, and pug) are at increased risk, probably because of a genetic anomaly within these breeds. However, affected puppies can be of any breed or a mixed breed.

Clinical Signs

Usually, the first clinical sign noticed is milk bubbling from the nose while the puppy is nursing or a defect in the upper lip. Puppies may cough or sneeze, and repeated nasal infections are common. Affected animals often fail to grow as fast as their littermates because they have problems swallowing milk and solid food. Aspiration pneumonia may occur when milk or food is inhaled into the lungs. Pneumonia can cause fever, lethargy, shortness of breath, and bad-smelling breath.

Diagnostic Tests

The diagnosis of a cleft palate is usually made by observing a space in the palate while examining the mouth. Sedation may be needed for a thorough examination and to assess how much tissue is absent, if surgery is to be attempted. Chest x-rays may be recommended if pneumonia is suspected.

TREATMENT AND FOLLOW-UP

Treatment Options

The best treatment option is to repair the cleft surgically. Surgical repair of cleft palate can be complex and may require several procedures. Depending on the severity of the lesion and the involvement of hard palate, soft palate, or both, your veterinarian may recommend referral to a veterinary surgeon. It is not unusual for the surgical site to heal slowly, and partial breakdown of the surgical site may occur, with one or more follow-up surgeries needed. Antibiotics are usually started in animals with pneumonia.

Follow-up Care

Patients require close monitoring after surgery. Chest x-rays are repeated in animals with aspiration pneumonia at 1- to 2-week intervals to assess response to therapy.

Prognosis

Prognosis depends on the complexity of the defect and how well it can be corrected with surgery. In many cases, the prognosis is guarded (uncertain) to poor, because surgical site breakdown and reopening of the cleft can occur. Neonates with a very severe cleft are often euthanized because their food intake is inadequate. If surgical repair of the cleft is successful, the prognosis is better, particularly if the animal is able to eat and drink successfully.

SPECIAL INSTRUCTIONS:

Colitis, Acute

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

Colitis is an inflammation of the colon. Acute colitis typically develops rapidly, with clinical signs that appear and disappear within a very short period.

Causes

The most common causes of acute colitis in dogs and cats are dietary indiscretion (eating something that does not agree with them) and bacterial infection (possibly from spoiled food). Some parasites of the gastrointestinal tract and certain drugs (such as aspirin) also cause colitis. Stress, such as being put into a kennel or hospital, can sometimes lead to acute colitis in a dog or cat.

Diagnostic Tests

A fecal sample is usually tested for parasites. If your pet has a fever or signs of dehydration, blood tests to assess the degree of dehydration and its effects on other organs, such as the kidneys and liver, are often recommended. If your pet has a high fever or has possibly been exposed to raw poultry meat or dead birds, culture of the feces for Salmonella bacteria may be recommended. X-rays, an ultrasound of the abdomen, or both are sometimes needed to look for other problems (such as constipation) that can cause similar clinical signs. There is no specific laboratory test for colitis; instead, the diagnosis is usually made from the clinical signs and history. Although the disease can be confirmed with colonoscopy and biopsy, they are rarely done, because the colitis usually resolves quickly.

TREATMENT AND FOLLOW-UP

Treatment Options

Most cases of acute colitis are self-limited, meaning that the signs usually resolve without the need for specific therapy. As the cause of the problem resolves or is passed from the gastrointestinal tract, the clinical signs disappear. Antibiotics are not usually helpful and may make matters worse, because they interfere with the normal bacteria in the gastrointestinal tract. Maintenance of adequate fluid intake and feeding of a relatively bland, easily digested diet are usually sufficient, and clinical signs often subside within 2-4 days.

If fecal analysis shows evidence of a parasite infestation, then routine, broad-spectrum anti-parasite medications will be prescribed.

If a patient is showing evidence of severe dehydration, either on physical examination or on results of blood tests, hospitalization for intravenous fluid therapy may be necessary. Patients with a high fever may be treated with antibiotic drugs. If a Salmonella bacterial infection is detected, people must be very careful to wash their hand after handling the animal, because Salmonella can infect people as well as animals.

Follow-up Care

In most cases, the clinical signs resolve rapidly, and there is no need for follow-up visits. If clinical signs do not resolve within 2-3 days, notify your veterinarian If Salmonella infection has been detected and treated with antibiotics, follow-up fecal cultures are needed to be certain that the infection has been eliminated. To prevent a recurrence, avoid feeding the animal any suspect foods, and keep the animal away from substances or situations that caused the colitis.

Prognosis

The prognosis for recovery in most cases of acute colitis is good. Most animals recover with only maintenance of adequate fluid intake and a bland, easily digested diet. Clinical signs should resolve within 2-3 days.

SPECIAL INSTRUCTIONS:

Colitis, Chronic

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

Colitis is inflammation of the colon or large intestine, the last part of the intestinal tract. Chronic colitis is suspected if clinical signs of colitis persist for longer than 7-10 days or recur frequently (sometimes up to 3-4 days per week).

Causes

The cause of chronic colitis is often hard to determine. Dietary allergies, food intolerance, and parasite infestations can cause similar signs and must be ruled out. In many cases, an underlying cause is never conclusively identified, so the condition is called idiopathic chronic colitis. The boxer breed may develop a specific form of chronic colitis called histiocytic ulcerative colitis, which is thought to arise from an infection in the large intestine. In other dog breeds, it is very unusual for infections to be the underlying cause.

Diagnostic Tests

Initially, a fecal sample is checked for parasites. If your pet has a fever or signs of dehydration, blood tests are usually recommended to assess the degree of dehydration and the effects on other organs such as the kidney and liver. X-rays of the abdomen or an abdominal ultrasound are sometimes needed to look for other problems, such as constipation, that can cause similar clinical signs.

The most effective method of diagnosing chronic colitis is through colonoscopy. This procedure allows your veterinarian to view the lining of the colon and look for ulcers, tumors, and inflamed areas. Animals need to be fully anesthetized for this procedure. Biopsy samples can be obtained during the colonoscopy. Many animals with chronic colitis also have inflammatory bowel disease in the stomach and small intestine, so colonoscopy may be combined with upper gastrointestinal tract endoscopy during the same anesthetic procedure. Your veterinarian may recommend referral to an internal medicine specialist to have these tests performed.

TREATMENT AND FOLLOW-UP

Treatment Options

Often the treatment for chronic colitis is as simple as changing the diet, because in many cases a dietary intolerance or food allergy is the underlying cause. The new diet is either specifically manufactured to be hypoallergenic or composed of a completely new source of protein (for instance, lamb instead of chicken). The decision to use a hypoallergenic diet or a new protein source depends on the number of different diet types your pet has consumed in the past.

Usually, if the new diet is going to be beneficial, an improvement in clinical signs is seen within 14 days. If no improvement occurs with diet changes alone, anti-inflammatory drugs, such as steroids, may be given. If steroid medications are started, all other nonsteroidal anti-inflammatory drugs (such as those used for arthritis) must be stopped, or side effects are likely to occur.

For boxers with histiocytic ulcerative colitis, 3-4 weeks of antibiotic therapy is usually beneficial, although signs may recur in some dogs. Antibiotics are used less often in other dogs, but they may be of benefit in some individual cases. Certain sulfa drugs and oral administration of probiotic bacteria may also benefit some dogs.

Follow-up Care

Many patients show improvement in approximately 2 weeks following a diet change or treatment with anti-inflammatory drugs. Failure to improve often indicates a need for further testing and evaluation or the addition of other medications. After the signs resolve, drug therapy is slowly tapered and may eventually be stopped. Notify your veterinarian if any signs recur as the medications are decreased.

Prognosis

Prognosis for most animals with chronic colitis is good, because clinical signs resolve in many patients, and all medications can be stopped. Occasionally, medications and periodic monitoring are needed for life.

SPECIAL INSTRUCTIONS:

Copper Storage Hepatopathy in Dogs

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

An important function of the liver is to remove toxic substances, such as copper, from the bloodstream. In some dogs, abnormalities can occur in the proteins that bind copper in liver cells. The liver of these dogs can still remove copper from the bloodstream, but it gradually accumulates to toxic amounts inside the liver cells. The affected cells die, which reduces the overall function of the liver. Breeds at high risk for copper storage hepatopathy include the Bedlington terrier, Doberman pinscher, Labrador retriever, cocker spaniels, West Highland white terrier, and Skye terrier. Abnormal copper accumulation can also occur with long-standing diseases of the bile system; however, the amount of copper that accumulates is significantly less than with primary copper storage hepatopathy.

Causes

In the Bedlington terrier, this disease arises from a mutation in the gene COMMD1, which contains the instructions for making a protein that is necessary for the excretion of copper from liver cells. In the other mentioned breeds, there is evidence that a genetic component may be involved, but the actual gene is not known at this time. Regardless of cause, clinical signs in affected dogs develop following the death of liver cells from excess copper.

Clinical Signs

Clinical signs of copper hepatopathy are the same as for most other liver diseases, and they can be vague and variable in the early phases of the disease. Dogs are often lethargic, may appear depressed, have decreased or complete loss of appetite, and have reduced exercise tolerance. In severely affected animals with diminished liver function, stupor or coma may develop, dogs may become extremely sleepy after eating, and excess fluid accumulation (ascites) may develop in the abdomen or under the skin.

Diagnostic Tests

Typically, the diagnosis is suspected when a dog of a breed known to be prone to this condition shows clinical signs of liver disease and routine laboratory tests indicate abnormal liver function. Additional laboratory tests, abdominal x-rays, and an ultrasound may be needed to confirm the presence of liver disease and to rule out diseases that can cause similar clinical signs.

Definitive diagnosis of copper storage hepatopathy requires a liver biopsy to measure the amount of copper that is present. Several methods are available for obtaining the liver biopsy, including needle biopsy under ultrasound guidance, laparoscopy surgery through a tiny keyhole incision, and a more routine surgical approach through an abdominal incision. The method chosen depends on the equipment available and the surgical experience and preference of your veterinarian. In some cases, your dog may be referred to a veterinary specialist for the procedure.

TREATMENT AND FOLLOW-UP

Treatment Options

The most important treatment for this hepatopathy is removal of the copper from the liver, which is done through a process called chelation. Chelation drug therapy with D-penicillamine binds the copper and releases it into the urine and feces. Once the amount of copper in the liver is decreased, steps are taken to reduce the accumulation of new copper by feeding a special diet that is extremely low in copper.

Additional drugs and supplements are commonly given, such as large amounts of vitamin C and zinc. Together, the vitamin C and the zinc make it more difficult for copper to be absorbed from the gut into the body. To work effectively, the zinc must be given at least 2 hours before the dog is fed. Some dogs have nausea and vomiting when zinc therapy is started, but these usually resolve within a week.

Follow-up Care

Regular follow-up visits and monitoring tests are needed during the initial phase of the therapy. A follow-up liver biopsy is often recommended after 2-3 months to measure the amount of copper present and determine whether drug therapy has been adequate. Once the low-copper diet has been started, liver tests may be rechecked every 3-6 months. Treatment and periodic monitoring are usually needed for the rest of the dog’s life.

Prognosis

If the disease is caught early and treated appropriately, many affected dogs can lead normal lives. Prognosis is more guarded (uncertain) for dogs that have severe clinical signs, because they may not be able to regenerate enough liver tissue to function normally.

SPECIAL INSTRUCTIONS:

Epulis in Dogs

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

An epulis is a small, rounded tumor found in the mouth of dogs at the edge of the gum line (the gingiva). These tumors arise from the tissues that hold the teeth in place. In some cases, the epulis can cause the teeth to change position, making it more difficult for the dog to eat. Most epulides are slow growing and may be present for several months before detection.

There are three main types of epulis, based on their manner of growth and the tissues involved:

• The most common types are the fibromatous and ossifying epulides. The ossifying epulis has areas of bone or tooth enamel within it. The fibromatous type contains bundles of connective tissue collagen.

• The rarest form, and the most worrisome, is the acanthomatous or squamous epulis. This type is able to invade the bone of the jaw and can lead to significant damage of the bones of the face or lower jaw if not treated appropriately and early.

Although an epulis is a type of tumor, it is usually benign. The acanthomatous type of epulis very rarely metastasizes (spreads to other parts of the body). Most commonly, this epulis invades the nearby bone.

Causes

There is no known cause of epulis in dogs. Some breeds, particularly the brachycephalic breeds (those with very short snouts, such as the pug, boxer, and English bulldog), seem to develop epulides more commonly, but the reason for this is unknown.

Clinical Signs

A very large epulis can affect eating. You may notice that the dog has trouble picking up food, drops food while chewing, or has trouble swallowing. Some dogs drool or have halitosis (bad-smelling breath) if the epulis becomes damaged and infected, or food particles become stuck in the epulis. A large epulis can also lead to distortion of the face and abnormal deviation of the teeth. If the epulis is damaged during chewing, blood may be seen on the lips or in food or water bowls.

Often, an epulis is only detected during a physical examination when your veterinarian checks the condition of the teeth and gums.

Diagnostic Tests

Diagnosis of an epulis is often made from the physical examination, based on observing a characteristic small tumor. Other forms of cancer in the mouth (such as oral melanoma and squamous cell carcinoma) are more worrisome than most forms of epulis, and tests may be needed to differentiate them from acanthomatous epulis. Your veterinarian may recommend x-rays or computed tomography (CT scan) of the jaw and skull, collecting cells from the tumor for examination under the microscope, or biopsy of the mass (which usually requires general anesthesia and surgery).

TREATMENT AND FOLLOW-UP

Treatment Options

Surgical removal of the epulis is the treatment most commonly recommended. It may involve the extraction of affected teeth as well. Failure to remove all of the affected tissue can allow the tumor to grow back. If the epulis is very large, especially if it is an acanthomatous epulis, large sections of jaw bone and multiple teeth may be extracted to improve the chance of a cure. In cases with invasion of the bone requiring extensive reconstructive surgery, your veterinarian may recommend referral to a surgery or oncology specialist.

Epulides are not usually responsive to chemotherapy. Radiation therapy is sometimes recommended for large acanthomatous epulides.

Follow-up Care

Most dogs recover from surgery for removal of an epulis rapidly and are soon back to normal. Sutures placed in the mouth may dissolve on their own over several weeks to months. After surgery, your dog’s mouth may be tender, and its appetite may be reduced for 2-3 days. Dogs having major surgery for removal of a very large epulis or acanthomatous epulis may need to be hospitalized for several days, given medications for pain, and fed through a tube to allow the surgical wounds to heal.

Prognosis

The prognosis for a cure following removal of a fibromatous or ossifying epulis is good, as long as an adequate amount of tissue is removed. The prognosis for an acanthomatous epulis is more guarded (uncertain), because the chance of a surgical cure depends on the size of the tumor, amount of bony invasion, location within the mouth, and the skill of the surgeon carrying out the procedure.

SPECIAL INSTRUCTIONS:

Esophageal Foreign Body

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

The esophagus is a muscular tube that carries swallowed food and water from the mouth to the stomach. Other than during swallowing, the esophagus should be empty. An esophageal foreign body is any item, either food or some other material, that has gotten caught somewhere in the esophagus.

The esophagus has several points where it becomes narrow and where material is most likely to get stuck. The narrow spots are at the beginning of the esophagus (upper esophageal sphincter), in the middle of the chest where the esophagus passes the heart, and at the very end where it enters the stomach (lower esophageal sphincter).

Causes

Esophageal foreign bodies occur when the animal attempts to swallow an object that is too large or sharp to pass smoothly through the esophagus. Swallowed fish hooks can lodge in the esophagus, but these do not usually cause complete obstruction.

Clinical Signs

Because the esophagus cannot work properly when a foreign body is present, food, water, and saliva are not swallowed properly. Regurgitation (similar to vomiting, but the food is not digested), drooling of saliva, and bad breath may occur. Regurgitation of blood-tinged fluid can be seen and is a worrisome sign. A fever may be detected.

Animals with an esophageal rupture or tear often have a high fever, are very depressed, are in pain, and may have shortness of breath.

Diagnostic Tests

If an esophageal foreign body is suspected, x-rays are taken of the chest and neck region. Some foreign materials, such as bones or metal, are readily seen on x-rays. Other foreign bodies are difficult to see with plain x-rays, and additional studies may be done after the animal is given an oral contrast agent (which shows up white on x-rays). This contrast procedure (esophagram) is often necessary with fabric foreign bodies (for instance, a swallowed sock), because they are difficult to see on plain x-rays.

Routine laboratory and other tests may be recommended to rule out diseases that cause similar signs, to assess any effects on other organs, and as a preoperative measure prior to surgery.

TREATMENT AND FOLLOW-UP

Treatment Options

Esophageal foreign bodies can be extremely serious problems. Animals with complete esophageal obstruction from a large foreign body need immediate therapy. Delaying therapy increases the risks of both short-term and long-term complications.

The best method of treatment is to remove the foreign body as soon as possible. Depending on the size of the animal and the foreign body, it may be possible to retrieve the foreign material through an endoscope that is passed through the mouth into the esophagus. Either a rigid or a flexible endoscope with grasping forceps may be used to view the foreign body and the lining of esophagus and to remove the material.

Surgery (via an incision into the esophagus) to remove the foreign body is very difficult, because the esophagus does not heal well. If a patient has a foreign body in the esophagus that requires surgical removal, your veterinarian may recommend referral to a veterinary surgery specialist for this procedure.

After the foreign body is removed, antibiotics, medications for pain, antacids, and medications to protect the lining of the esophagus are usually begun. Supportive care with intravenous fluids may also be started. Animals with severe esophageal damage may have a feeding tube placed into the stomach that allows the animal to receive food and water without passing them through the esophagus. The feeding tube usually stays in place for at least 2 weeks.

Follow-up Care

Intensive monitoring may be required following rupture of the esophagus. Postoperative visits are usually scheduled 1-2 weeks after removal. Notify your veterinarian if any signs of regurgitation, loss of appetite, or fever occur.

Prognosis

Prognosis for complete recovery is good if there is no damage to the lining of the esophagus. The amount of damage to the lining increases with the amount of time that the foreign body is left in place, so the prognosis becomes poorer with long durations.

Some animals that have severe damage to the esophagus will form a stricture at some time after removal of the obstruction. The stricture arises from scarring and reduces the diameter of the esophagus. If this happens, clinical signs of regurgitation will return.

Severe damage and rupture of the esophagus have a poor prognosis, because these cases are often complicated by infection that develops within the chest. In these cases, the condition can be life-threatening.

SPECIAL INSTRUCTIONS:

Esophagitis and Esophageal Stricture

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

The esophagus is a muscular tube that carries swallowed food and water from the mouth to the stomach. The esophagus is very sensitive to damage from stomach acid, so any medical problem leading to excess stomach acid in the esophagus can cause inflammation, which is called esophagitis. In people, the same condition is called heartburn or acid reflux disease.

Some animals with severe esophagitis will later form an esophageal stricture—scarring that reduces the esophageal diameter. When the diameter of the esophagus is reduced by a stricture, the animal is less able to swallow food and water.

Causes

The esophagus can be exposed to stomach acid during profuse vomiting or gastric reflux, from eating high-fat foods, or during or after an anesthetic procedure. Esophagitis can also occur with some forms of food allergy, certain infections, and after trauma from ingestion of foreign bodies. Structural abnormalities of the esophagus, such as a hernia, may predispose the animal to esophagitis. Certain oral medications and the ingestion of irritating materials can also cause esophagitis.

Clinical Signs

Esophagitis can be painful, causing affected dogs and cats to lose their appetite. If the animal has difficulty swallowing, drooling of salvia and regurgitation of food or water may be seen.

When an esophageal stricture is present, food and water are less able to travel to the stomach, and the animal may act very hungry. Water and very soft food may be able to pass through the stricture, but harder foods, such as kibble or biscuits, may be regurgitated.

A possible complication of both esophagitis and esophageal stricture is aspiration pneumonia, which develops when food or liquids are inhaled into the lungs. If aspiration pneumonia is present, coughing, fever, lethargy, and halitosis (bad breath) may occur.

Diagnostic Tests

Initially plain x-rays of the neck and chest are often done to assess the esophagus. It is common for more specialized x-rays to be taken after the patient has been given an oral contrast material that shows up white on an x-ray. This procedure is called an esophagram, and it is particularly useful if an esophageal stricture is suspected.

In some animals, esophagoscopy, which is examination of the interior of the esophagus with a rigid or flexible endoscope, is needed. Esophagoscopy is done with the animal anesthetized. The endoscope allows the veterinarian to see foreign bodies, strictures, or ulcers in the esophagus and also allows biopsy samples to be obtained. Examination of the stomach and upper small intestines may be done at the same time.

Other tests may be recommended to rule out diseases that cause similar signs and to determine the underlying causes of any acid reflux present.

TREATMENT AND FOLLOW-UP

Treatment Options

The esophagus is very susceptible to damage from stomach acid, so strong antacid medications are commonly prescribed. Other medications that help protect the esophagus from damage may also be started. Antibiotics and antifungal agents may be given for certain infections and for aspiration pneumonia. If regurgitation or vomiting is occurring, other drugs are administered to decrease these signs. Food is given in small meals, and usually softer foods are more readily accepted.

Animals with an esophageal stricture may require breakdown of the stricture. Strictures are usually treated by passing special water-filled balloon catheters into the esophagus while the animal is anesthetized. The catheter is passed into the area of the stricture and slowly expanded. Several such treatments may be necessary. Your veterinarian may recommend referral to a specialist who can perform this procedure.

Animals with severe esophageal damage may have a feeding tube placed into the stomach that allows the animal to receive food and water without passing them through the esophagus. The feeding tube usually stays in place for at least 2 weeks. Other therapies may be indicated, depending on the presence of any underlying cause of the esophagitis.

Follow-up Care

Uncomplicated cases of esophagitis are usually rechecked 7-10 days after starting therapy and then periodically for several months. More intensive monitoring is needed in cases with severe esophagitis or strictures and after insertion of a feeding tube.

Prognosis

Prognosis for recovery from uncomplicated esophagitis is usually good. Prolonged treatment may be required in some cases. Severe cases have a more guarded (uncertain) prognosis, particularly if aspiration pneumonia is present or a feeding tube is needed. Many animals with esophageal strictures return to more normal eating and esophageal function with treatment.

SPECIAL INSTRUCTIONS:

Exocrine Pancreatic Insufficiency

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

The pancreas is a flat, glandular organ that is found in the upper part of the abdomen, near the stomach and liver. The pancreas has three major functions. One part of the pancreas, called the endocrine pancreas, produces the hormone insulin, which regulates blood glucose. The bulk of the pancreas, called the exocrine pancreas, produces the enzymes necessary to digest food. The last major function of the pancreas is to produce fluid and bicarbonate for mixing of food in the intestines. Exocrine pancreatic insufficiency (EPI) occurs when there is a loss of exocrine pancreas tissue and the animal cannot make enough enzymes for normal digestion. EPI can occur in both dogs and cats, but the disease is very rare in the cat.

Causes

The most common cause of EPI in the dog is a condition called pancreatic acinar atrophy. Dogs with this condition gradually lose the exocrine cells in the pancreas, for reasons that are unclear. Pancreatic acinar atrophy is most common in the German shepherd dog and the rough-coated collie. In these breeds, it is thought to be an inherited disease. Although EPI arises most often in these breeds, dogs of any breed can be affected. Cats and some smaller dog breeds may develop EPI if they have chronic pancreatitis for an extended period of time. Pancreatic acinar atrophy tends to occur in young adult dogs (often less than 2 years of age), whereas EPI associated with chronic pancreatitis tends to occur in middle-aged to older animals.

Clinical Signs

Because the animal is unable to digest food properly, signs of maldigestion are present. The most common sign is diarrhea. The animal usually passes feces that are very soft and pulpy, and the total volume of feces produced in a day is often dramatically increased. Since food is not being absorbed properly, the animal is unable to take in enough energy and usually loses weight or does not grow appropriately. Dogs often have a dramatically increased appetite and may eat their own feces (coprophagia). Cats are less likely to have an increased appetite and very rarely develop coprophagia. Vomiting may occur occasionally, and the hair coat may be of poor quality. (Also see the handouts on Pancreatitis in Dogs and Pancreatitis in Cats.)

Diagnostic Tests

Because the major clinical sign of exocrine insufficiency is diarrhea, other diseases that can cause diarrhea must be ruled out. Routine laboratory tests, fecal examinations, and x-rays may all be recommended.

To test the amount of pancreas tissue that is present, a specialized blood test is used. This test measures the amount of a digestive enzyme, called trypsin, in the bloodstream. Low levels of trypsin indicate that the pancreas is not producing enough enzymes. Other specialized tests for diseases of the small intestine are often run at the same time.

TREATMENT AND FOLLOW-UP

Treatment Options

The best treatment for EPI is to provide an oral supplement of digestive enzymes. These enzymes come in tablet and powder forms and are extracted from the pancreases of cows and pigs. Dietary supplements using plant enzymes do not work as well as enzymes from animal sources. The digestive enzymes are given with every meal and are usually required for the rest of the animal’s life.

Feeding a lower-fat diet often helps to reduce the severity of the diarrhea. Vitamin supplements are often recommended, such as vitamins A, K, and B12. Some animals are also given antacid medications or antibiotics because of the presence of excessive numbers of bacteria in the small intestines.

Follow-up Care

Typically, a significant improvement in diarrhea and weight gain is seen within 14 days after starting the enzyme supplements. Body weight, consistency of the feces, appetite, and coprophagia are all monitored. High doses of enzymes may cause bleeding of the gums, which requires lowering the dose. Notify your veterinarian if initial signs do not improve or recur, or if new signs develop.

Prognosis

The prognosis for most dogs with EPI is good, assuming that the enzyme treatment is given properly. A poor response occurs in about 20% of affected dogs. Therapy is usually lifelong and can be expensive in large dogs. For cats, the prognosis is more guarded (uncertain). Cats are often harder to treat with the digestive enzymes because they avoid their food when the enzymes are added. Affected cats also tend to develop diabetes mellitus (sugar diabetes), which can be difficult to manage.

SPECIAL INSTRUCTIONS:

Fecal Incontinence

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

Fecal incontinence occurs when a loss of control of the lower bowel and rectum allows feces to be passed at inappropriate times or places. Fecal incontinence may be neurogenic in origin (neurogenic incontinence) and associated with a failure of nervous sensation. In these cases, the animal does not realize that it is defecating (involuntary defecation) and does not assume the normal posture for defecation. In contrast, urge incontinence may occur with uncontrolled or strong urges to defecate. In these cases, the animal acutely needs to defecate and is aware of that need.

Causes

Diseases of the nerves in the lower spine, of the rectum and anus, and of the large intestine can all result in fecal incontinence. Diseases of the nerves in the lower spine include intervertebral disc disease and chronic arthritic changes. Masses or tumors in the wall of the rectum or in the pelvic canal can lead to excessive straining. Urge incontinence can result from inflammation of the lower colon or rectum. (See also the handout on Acute Colitis.) Some older animals develop incontinence from of a decline in their mental status (cognitive dysfunction, senility), which leads them to become less attentive to many aspects of daily life.

Clinical Signs

The major sign is the passing of feces at inappropriate times or places. Frequent, repeated requests to go outside to defecate, as well as repeated or unproductive straining are signs of colitis. Passing feces while walking; leaving bowel movements on the floor or bedding after rising; and continued dribbling of feces while being unaware of the defecation are typical of neurogenic fecal incontinence. In aged animals, loss of awareness of whether they are inside or outside, with indiscriminant defecation in a variety of locations, is often indicative of senile cognitive dysfunction.

Diagnostic Tests

Examination of the rectum and anus with a gloved finger is usually done to check the strength of the rectal sphincter and the presence of masses or other diseases. Routine laboratory tests, x-rays, and an abdominal ultrasound may be recommended to screen for pelvic, spinal, or other diseases. In some cases, computed tomography (CT scan) or magnetic resonance imaging (MRI) of the lower spine may be needed to assess the spinal cord and nerve roots in the lower back.

TREATMENT AND FOLLOW-UP

Treatment Options

If a primary cause of the incontinence can be identified, such as a slipped disc in the spine or severe degenerative joint disease in the lower back and pelvis, your veterinarian may recommend surgery. These types of surgery can be complex and difficult, so your pet may be referred to a veterinary specialist for further evaluation and care.

Animals with fecal incontinence from colitis generally respond well to changes in diet and/or anti-inflammatory drugs. Animals with fecal incontinence from cognitive dysfunction may be treated with drugs that stimulate mental activity, although these treatments do not produce a reliable positive response in all animals. No effective treatment is available for some forms of neurogenic incontinence.

Follow-up Care

Regular follow-up visits are recommended, especially during the initial phase of treatment of colitis or spinal disease. Once clinical signs are controlled, repeated follow-up visits may not be needed. Incontinence associated with more chronic conditions often requires long-term monitoring and follow-up.

Prognosis

Prognosis varies widely, depending on the cause of the fecal incontinence. Animals with urge incontinence from lower-bowel disease have a good prognosis once their condition is controlled. Prognosis for incontinence resulting from cognitive decline or neurologic disease is more variable and generally poorer, because these conditions are much more difficult to control.

SPECIAL INSTRUCTIONS:

Gall Bladder Disease in Dogs

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

The gall bladder is a small pouch or sac that contains bile produced by the liver. The gall bladder stores bile until it is released into the small intestine, where it helps in the digestion of fat. In people, the most common disease of the gall bladder is gall stones. In dogs, inflammation of the gall bladder can occur, but the formation of hard stones is uncommon. The gall bladder can also become infected by bacteria, and some cancers can develop in the gall bladder, but these disorders are less common than the condition called biliary mucocele. A mucocele develops when bile becomes thickened and is retained in the gall bladder, causing it to become enlarged.

Causes

The cause of most gall bladder disease, particularly biliary mucocele, is not well defined in the dog. Many dogs with gall bladder disease have some sort of underlying metabolic or hormonal problem. Both hypothyroidism (low thyroid hormone levels) and hyperadrenocorticism (excessive steroid hormone levels) are associated with an increased risk of developing a biliary mucocele.

Clinical Signs

Common signs of gall bladder disease include a poor appetite, weight loss, vomiting, and diarrhea. In some dogs with severe obstruction of the gall bladder, the feces become a light tan to gray color due to lack of bile, which contains pigments that eventually turn the feces brown. The dog may also have jaundice (yellow discoloration of the gums, whites of the eyes, and skin). If the gall bladder is ruptured, bile peritonitis often develops, and the dog becomes severely ill. The dog may collapse, go into shock (with weak pulses), develop a high fever, have a painful abdomen, and be severely dehydrated.

Diagnostic Tests

Routine laboratory tests are used to assess the state of the liver, the presence of severe inflammation, and the degree of dehydration. X-rays of the abdomen may be recommended. The best method of assessing the gall bladder is an abdominal ultrasound. The gall bladder is usually easy to see on ultrasound. If a mucocele is present, marked thickening of the gall bladder wall is commonly present, and the gall bladder is filled with thick, dehydrated, sludge-like bile. The abnormal bile and thickened wall give the gall bladder an appearance similar to a cross-sectioned kiwi fruit. If a gall bladder mucocele is not identified on ultrasound, a biopsy of the liver and a bile sample may be submitted for microscopic examination and bacterial culture. Other tests may be recommended to rule out other diseases that cause similar signs.

TREATMENT AND FOLLOW-UP

Treatment Options

A sick dog with a biliary mucocele is usually a surgical emergency, because the obstructed gall bladder must be removed before it ruptures. Rupture of the mucocele, particularly if it is infected by bacteria, leads to bile peritonitis, which can be life-threatening. If a mucocele is detected before the dog becomes ill, surgery to remove the gall bladder is still recommended. Gall bladder surgery can be technically challenging and carries significant risks, so your dog may be referred to a veterinary surgery specialist for the procedure.

If formation of the mucocele is incomplete, drugs may be tried that make the bile more watery and allow it to flow more easily. Dogs treated medically require close monitoring, because their condition can rapidly deteriorate if the mucocele worsens.

Follow-up Care

Frequent follow-up visits are usually needed when a mucocele is treated medically. At least monthly abdominal ultrasounds and laboratory testing are often recommended.

Following surgery, the dog is hospitalized and closely monitored for several days. Postoperative follow-up visits are often continued until all laboratory tests have returned to normal.

Prognosis

Surgery to remove a gall bladder mucocele is relatively risky. Even in the hands of experienced surgeons and with good intensive postoperative care, about 1 in 10 dogs die during surgery or immediately (24-36 hours) afterward. If the gall bladder has ruptured and bile peritonitis is present, the mortality rate increases to 1 in 4 dogs. If the gall bladder was infected when it ruptured, the dog may die during the surgery or within 24 hours of surgery.

If an underlying medical condition can be identified and drugs can dissolve the bile, the prognosis may be better but it is still guarded (uncertain), because these dogs can worsen rapidly even with appropriate treatment.

SPECIAL INSTRUCTIONS:

Gastric Dilatation-Volvulus

Rhea V. Morgan, DVM, DACVIM (Small Animal), DACVO

BASIC INFORMATION

Description

Gastric dilatation-volvulus (GDV) is an acute, life-threatening emergency. Gastric dilatation involves the sudden accumulation of gas and fluid in the stomach and is sometimes called bloat. Volvulus is the twisting of a bloated stomach so that the openings into and out of the stomach are blocked. As the stomach rotates, it may also cause the spleen to become displaced. GDV causes blood flow to the stomach to be compromised and is often accompanied by shock.

Causes

The exact reason for stomach bloating is unknown. Middle-aged or older, large- and giant-breed dogs are at the highest risk, but GDV can occur in small-breed dogs and cats (rare). The following are considered risk factors for bloat:

• Large- or giant-breed dogs with deep chests and lean body condition

• Dogs with close relatives that have experienced GDV

• Behaviors that promote the swallowing of air

• Stress and nervous temperament

• Feeding large volumes of food at each meal

• Feeding dry foods that contain high quantities of fat or oil

• Conditions that decrease outflow of material from the stomach

Clinical Signs

Restlessness and agitation may be the first signs noted. Affected dogs often pace, are reluctant to lie down, and retch or try to regurgitate; they may have excessive drooling. The abdomen may be noticeably distended and painful. As the duration of GDV increases, the animal may become weak, collapse, and have pale and/or dry gums. Rate and effort of breathing may also be increased.

Diagnostic Tests

A tentative diagnosis may be made by observing a distended, rigid abdomen in a dog of the appropriate age and breed. Certain changes on physical examination may allow your veterinarian to suspect the presence of GDV and shock. X-rays of the abdomen are used to assess the position of the stomach and to confirm the presence of dilatation and/or volvulus. However, x-rays are sometimes delayed until the dog has been stabilized with emergency procedures. Laboratory tests are commonly recommended to evaluate the effect of the GDV on other organs and body chemistries. An electrocardiogram may be indicated if an irregular heartbeat (arrhythmia) is detected.

TREATMENT AND FOLLOW-UP

Treatment Options

GDV is an emergency situation, and therapy is directed at both relieving the distention of the stomach and treating shock. Treatment for shock involves the administration of intravenous fluids and medications. The stomach is decompressed by passing a tube from the mouth into the stomach and evacuating all stomach contents. Decompression may not be possible if the stomach is twisted and the tube cannot be passed. In this instance, needles may be inserted into the stomach through the abdominal wall to release air, or a temporary opening may be made into the stomach through the side of the abdomen. Monitoring of the heart and administration of heart medications may also be started.

Once the animal is stable, surgery is usually performed to assess the health of the stomach; correct any volvulus and return the stomach and spleen to a normal position; remove any irreversibly damaged parts of the stomach and spleen; and permanently attach the stomach to the abdominal wall (gastropexy), so that the stomach cannot twist again in the future. Although some dogs with simple, short-lived bloat may not require surgery, most patients with GDV undergo surgery as soon as shock, heart arrhythmias, and other abnormalities are corrected.

Several surgical gastropexy techniques are available, including the incisional, belt-loop, and tube gastropexies, as well as others. Most of these techniques anchor the stomach wall to the right side of the abdomen.

Follow-up Care

Dogs with GDV require immediate intensive therapy, monitoring, and supportive care; without such care, the condition usually rapidly deteriorates and results in death. GDV can cause biochemical abnormalities, blood pressure problems, heart arrhythmias, secondary infections, damage to the lining and wall of the stomach, alterations in the spleen, and a life-threatening blood-clotting disorder, so laboratory tests and other monitoring procedures are commonly needed.

Postoperatively, intensive therapy is continued for several days. Food and water are usually withheld for 12-24 hours. Exercise is restricted until sutures are removed and the gastropexy site has healed. Your veterinarian may recommend changing the type, amount, and frequency of feedings.

Prognosis

Many dogs recover well, provided the GDV is diagnosed and treated quickly. Prognosis is poorest for animals with severe damage and perforation of the stomach and those with serious secondary infections (sepsis, peritonitis) or heart arrhythmias.

SPECIAL INSTRUCTIONS:

Gastric Foreign Body

Craig G. Ruaux, BVSc, PhD, DACVIM (Small Animal)

BASIC INFORMATION

Description

A gastric foreign body is any item, either food or nonfood material, that is present in the stomach and does not pass into the small intestine or is vomited. Some gastric foreign bodies can cause severe vomiting or intestinal obstruction, and others (such as coins or metal toys) can poison the animal.

Causes

Gastric foreign bodies occur when something is swallowed but cannot leave the stomach. They may include large pieces of bone, an item that the animal was playing with, accumulations of hair (hair balls), and abnormal material eaten (such as dirt, rocks, or kitty litter).

Some animals eat unusual items if they have nausea, such as can occur with gastritis. Some animals eat unusual items as part of a behavioral problem or as the result of a medical condition (such as anemia or Cushing’s disease). The consumption of unusual items is called pica.

Clinical Signs

The most common clinical sign of a gastric foreign body is vomiting. Some animals also lose their appetite. If the foreign body is made of zinc, the animal may develop anemia (pale gums, lethargy, and weakness). If the foreign body is made of a heavy metal such as lead, signs of poisoning may occur. (See also the handouts on Zinc Toxicosis and Lead Poisoning.) Often, gastric foreign bodies are found when x-rays are performed on an animal with vomiting problems.

Diagnostic Tests

If a gastric foreign body is suspected, abdominal x-rays are commonly recommended. Routine laboratory tests and an abdominal ultrasound may also be recommended to rule out other conditions, such as liver, pancreatic, or kidney diseases that can cause vomiting.

A contrast study (gastrogram) of the stomach may be performed if a foreign body is suspected but not found on plain x-rays. In a gastrogram, barium or some other agent is administered orally to help highlight any foreign material. In some cases, foreign bodies are found during examination of the stomach with an endoscope (gastroscopy) or during exploratory surgery.

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Tags: Small Animal Practice Client Handouts

Sep 11, 2016 | Posted by admin in SMALL ANIMAL | Comments Off

Fastest Veterinary Medicine Insight Engine

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