Megaesophagus in Cats

The esophagus is the first portion of the digestive tract after the mouth. A healthy esophagus transports food from the mouth to the stomach by muscular squeezing (a process called peristalsis) along the tract. If the esophagus decreases its ability to move food through to the stomach, chewed food can build up in the tract, causing it to expand. If this persists, it can lead to a chronic widening of the esophagus, called megaesophagus.

Megaesophagus is rare in cats, but can lead to life-threatening complications such as aspiration pneumonia and malnutrition. Cats showing symptoms such as regurgitation, weight loss, and difficulty swallowing require prompt veterinary examination to identify the underlying cause.

Cats with megaesophagus are predisposed to developing aspiration pneumonia, a serious and potentially life-threatening condition.

Megaesophagus is caused either by a disruption to motility of the tract (the ability of the tract to push food through) or by an existing obstruction preventing food from passing to the stomach.

Megaesophagus has both congenital (present at birth) and acquired (develops during a cat’s lifetime) forms.

Congenital megaesophagus is very rare. Some cases are associated with congenital myasthenia gravis, and some cases have no apparent underlying cause (idiopathic). Abyssinian and Siamese cats are most at risk of congenital megaesophagus.

Acquired megaesophagus has many potential causes.

The major symptom of megaesophagus is regurgitation. Regurgitation requires no abdominal effort and causes no distress to the animal, in contrast with vomiting. Cats that regurgitate seem to suddenly have food material in their mouth with no signs leading up to the event.

Diagnosis of megaesophagus starts with a physical examination. Other tests that may aid in diagnosis include:

• Blood work
• Diagnostic imaging
• Esophagoscopy
• Testing for specific underlying conditions such as myasthenia gravis

Treatment of megaesophagus primarily focuses on preventing aspiration pneumonia while meeting a cat’s nutritional needs. If possible, treating the underlying condition can resolve megaesophagus. Many cats require placement of a gastrostomy tube for feeding while treatment for their underlying condition takes place. Long-term methods for managing megaesophagus include:

• Altering the consistency of food to ensure passage into the stomach
• Placing feed and water bowls in an elevated position
• Use of a “Bailey chair”, which keeps a cat in an upright position during feeding. These chairs are commonly used for dogs, but may not be tolerated by cats.

Most causes of megaesophagus require life-long therapy, including intensive management to prevent aspiration pneumonia and malnutrition. Many cats with megaesophagus develop severe complications such as aspiration pneumonia despite appropriate treatment and management. These cats are often euthanized due to poor prognosis.

There is no way to prevent megaesophagus in cats. Megaesophagus is not contagious.

Megaesophagus is rare in cats.

• Nutritional management
• Treating the underlying cause