Esophageal strictures in cats and dogs: Signs, causes and treatment

A recent publication discussed the outcomes and risk factors associated with the treatment of benign esophageal strictures (BES) in veterinary patients with esophageal bougienage.1 It provided a good overview of this condition, including common causes, risk factors, diagnosis and treatment.

Causes and risk factors

BES, caused by a circumferential narrowing of the esophageal lumen by fibrosis, usually occurs one to three weeks after the initial inciting cause of esophagitis. The most common causes of esophagitis are gastroesophageal reflux and trauma secondary to an esophageal foreign body. BES must be differentiated from other causes of esophageal strictures such as a persistent right aortic arch or malignant strictures caused by neoplastic processes.

In the study, the authors noted that the risk factors for developing BES in dogs included a recent history of general anesthesia, oral antimicrobial administration, vomiting and being female. In cats, risk factors included having a recent history of general anesthesia, vomiting and gastrointestinal tract trichobezoars.

Table 1: Causes of esophagitis or BES

Diagnosis

Often, an initial diagnosis of BES is based on a typical etiologic history and clinical signs (Tables 1 and 2). These clinical signs are usually progressive. Confirmation of this diagnosis can be challenging. Physical examination generally shows no abnormalities, though weight loss may be evident.

Table 2: Clinical signs of esophageal strictures

Hematologic analysis, serum chemistry profile and urinalysis results are generally unremarkable. Plain film thoracic radiography may show varying degrees of esophageal dilation or evidence of an esophageal foreign body. Contrast radiography using liquid barium or barium mixed with food may show evidence of esophageal dilation or further support the evidence of an esophageal foreign body (Figure 1). Most animals have a single stricture, which is confirmed by esophagoscopy.2 Mucosal biopsy and endoscopic exfoliative cytology may permit the differentiation of benign vs. malignant stricture.2

Figure 1: Contrast radiography demonstrating esophageal dilation rostral to a stricture.

Treatment

BES is best treated with mechanical dilation using a balloon catheter under endoscopic guidance.2 Treatment can be frustrating and costly because of the necessity of multiple anesthetic episodes and the use of specialized equipment. Esophageal dilations are usually performed two to four times under separate anesthetic episodes at two- to three-day intervals. This dilation process may need to be repeated an indeterminate number of times, depending on the patient's clinical response, and the risk of esophageal tear from this procedure is ever present.

In addition to mechanical dilation, medical therapy for an extended length of time for esophagitis is indicated (Table 3). In severe cases in which the patient is unable to provide itself with adequate nutrition, a gastrotomy tube for enteral feedings is necessary to provide a portal while allowing the esophagus to heal. Placing a stomach tube also provides an often-overlooked opportunity to obtain specimens for full-thickness stomach, small intestinal, pancreatic and liver biopsies to rule out underlying causes for vomiting (e.g., gastritis, inflammatory bowel disease, liver disease, pancreatitis, gastrinoma).

Table 3: Medical treatment for esophagitis

Note, about 65 percent of esophageal strictures are attributed to anesthesia.3 Peristalsis is markedly delayed in anesthetized animals, allowing the acid, which usually is returned rapidly to the stomach, to be in contact with the esophagus for extended periods.3 Since BES is often linked to a recent anesthetic procedure, antacid therapy, unless contraindicated, should be considered as a preventive measure just prior to and several days after any procedure requiring general anesthesia.

Final thought

This study concluded that using bougienage (with the use of guide wires) as part of the management of BES was as safe and effective as using balloon dilation. However, the use of freely passed bougies (those passed without a guide wire) may more likely be associated with esophageal perforation.

Dr. Lyman is a graduate of The Ohio State University College of Veterinary Medicine. He completed a formal internship at the Animal Medical Center in New York City. Lyman is a co-author of chapters in the 2000 editions of Kirk's Current Veterinary Therapy XIII and Quick Reference to Veterinary Medicine.

Dr. Runde is a graduate of the University of Pennsylvania School of Veterinary Medicine. He completed an internship at Hollywood Animal Hospital. He is an associate veterinarian at the Animal Emergency and Referral Center, Ft. Pierce, Fla.

REFERENCES

1. Bisset, SA, Davis, J, Subler, K, et al. Risk factors and outcome of bougienage for treatment of benign esophageal strictures in dogs and cats: 28 cases (1995-2004). J Am Vet Med Assoc 2009;235(7):844-850.

2. Jergens, AE. Diseases of the esophagus. In: Ettinger, SJ, Feldman EC, eds. Textbook of veterinary internal medicine. 6th ed. St. Louis, Mo: Elsevier Saunders, 2005;1298-1310.

3. Willard, DW, Carsten WC. Esophagitis. In: Kirk RW, ed. Current veterinary therapy XIV. St. Louis, Mo: Elsevier Saunders, 2009;482-486.