BASICS

DEFINITION
An abnormal narrowing of the esophageal
lumen

Pathophysiology
Esophageal stricture is most often caused by fibrosis secondary to severe ulcerative inflammatory changes in the esophageal mucosa, submucosa, and muscularis. Gastroesophageal reflux, injury from swallowed chemicals, and esophageal foreign body are the most important causes of esophageal inflammation (see Esophagitis). Esophageal stricture can also be caused by esophageal surgery and by intraluminal or extraluminal mass lesions (e.g., neoplasia or abscess). Spirocerca lupi granuloma is occasionally associated with esophageal stricture.

Systems Affected
• Gastronintestinal--esophagus affected segmentally or diffusely
• Respiratory-- aspiration pneumonia may develop secondary to regurgitation

Genetics
No apparent genetic basis

Incidence/Prevalence
Unknown but believed to be low

Geographic Distribution
Spirocerca lupi granulomatous strictures are occasionally seen in the Southeastern United States. No specific geographic distribution for other causes.

SIGNALMENT

Species Dogs and cats

Breed Predilections None reported

MEAN AGE AND RANGE
Any age, but neoplastic strictures tend to occur in middle-aged to old animals

PREDOMINANT SEX None

SIGNS

General Comments
• Clinical signs related to the severity and extent of esophageal stricture.
• Stricture can occur in any segment or over any length of the esophagus.

Historical Findings
• Regurgitation--usually observed shortly after feeding, and affected animals may reingest the regurgitated meal. Liquid meals often tolerated better than solid meals
• Dysphagia
• Good appetite initially, but eventually anorexia with progressive esophageal narrowing and inflammation
• Weight loss and malnutrition as the disease progresses
• Aspiration pneumonia with progressive
regurgitation and dysphagia

Physical Examination Findings
• Aside from cachexia and malnutrition, the physical examination is often nonremarkable
• Salivation may be observed in animals that have concurrent esophagitis.
• Pulmonary wheezes and coughing may also be detected in animals with aspiration pneumonia.

CAUSES
• Ingestion of chemical irritants
• Gastroesophageal reflux of gastric and intestinal juice
• Esophageal foreign body
• Esophageal surgery
• Malignancies-- intramural and extramural
• Spirocerca lupi granuloma

RISK FACTORS
Anesthesia--poor patient preparation and poor patient positioning during anesthesia place some animals at risk for gastroesophageal reflux, esophagitis, and subsequent stricture formation.


DIAGNOSIS

DIFFERENTIAL DIAGNOSIS
• Vascular ring anomaly--an important differential diagnosis in a young animal with midesophageal body stricture and proximal esophageal dilation. These animals are usually examined shortly after weaning.
• Esophagitis --patient may have identical clinical signs as those of esophageal stricture. Differentiation requires barium contrast radiography or endoscopy.
• Intraluminal mass--often detected by radiography, but some may require endoscopy. Leiomyoma, squamous cell carcinoma, fibrosarcoma, and osteosarcoma are the most common esophageal malignancies.
• Extraluminal periesophageal mass--often detected by radiography, but may require thoracic ultrasonography. Lymphosarcoma, heart base tumor, and mediastinal abscessation are the most common causes of extraluminal esophageal compression.

CBC/BIOCHEMISTRY/URINALYSIS
Results usually normal. Animals with ulcerative esophagitis or aspiration pneumonia may have leukocytosis and neutrophilia.

OTHER LABORATORY TESTS N/A

IMAGING
• Survey thoracic radiographs are usually normal. An intraluminal or extraluminal mass lesion may occasionally be seen. Aspiration pneumonia may also be evident in animals with dysphagia and frequent regurgitation.
• Barium contrast radiography is usually diagnostic for the disorder. Segmental or diffuse narrowing is observed with liquid barium and barium meal. Some dilation proximal to the stricture may be seen.
• Ultrasonography has not proved useful in diagnosing this disorder, unless an extramural compressive mass lesion is suspected.

OTHER DIAGNOSTIC PROCEDURES
Endoscopy should be performed in all patients to confirm the site and severity of stricture and to exclude the possibility of intraluminal malignancy.

GROSS AND HISTOPATHOLOGIC FINDINGS
• Esophageal stricture
• Esophagitis in some patients
• Dilation and muscular hypertrophy proximal to the stricture
• Aspiration pneumonia


TREATMENT

INPATIENT VERSUS OUTPATIENT
Initially inpatient. Animals may be discharged from the hospital after adequate rehydration, dilation of the affected segment, and appropriate treatment for aspiration pneumonia.

ACTIVITY Regular

DIET
Oral feedings should be withheld in animals with severe esophagitis. In such patients, a temporary gastrostomy tube may be placed at the time of esophageal dilation as a means of providing continual nutritional support. Liquid meals should be used when reinstituting oral feedings.

CLIENT EDUCATION
• Animals do not recover from untreated esophageal stricture.
• Benign strictures are best treated by esophageal dilation.
• Animals with malignant stricture have a poor prognosis.
• Discuss probability of recurrence.

SURGICAL CONSIDERATIONS
• Esophageal stricture is probably best managed by mechanical dilation with bougienage tube or balloon dilation catheter. Balloon dilation is probably safer and more effective than by bougienage tube. Balloon dilation applies radial forces to expand the stricture site. A greater risk of perforation is associated with the use of bougienage tubes because of shearing forces applied by the instrument. Redilation at 1-2 week intervals may be necessary with either approach until the stricture is resolved.
• Surgical resection of esophageal stricture has been reported, but surgical failure and stricture recurrence are common. Jejunal and colonic interposition surgeries have been described but they are technically difficult to perform.


MEDICATIONS

DRUGS AND FLUIDS
• Animals with concurrent esophagitis should be given sucralfate suspension (0.5-1.0 grams PO q8h) and a gastric acid antisecretory agent (cimetidine 5-10 mg/kg PO q8h; ranitidine 0.5 mg/kg PO q12h; or omeprazole 0.7 mg/kg PO q24h).
• Anti-inflammatory dosage of corticosteroids (e.g., prednisone 0.5-1.0 mg/kg PO q12h) has also been advocated to prevent fibrosis and restricture during the healing phase.

CONTRAINDICATIONS None

PRECAUTIONS None

POSSIBLE INTERACTIONS
Sucralfate may inhibit the gastrointestinal absorption of other drugs (e.g., cimetidine, ranitidine, and omeprazole)

ALTERNATE DRUGS N/A


FOLLOW-UP

PATIENT MONITORING
Repeat barium contrast studies or endoscopy every 2-3 weeks until clinical signs have resolved and adequate esophageal lumen has been achieved.

PREVENTION/AVOIDANCE
Prevent animals from ingesting caustic substances and foreign bodies.

POSSIBLE COMPLICATIONS
Esophageal perforation is a potentially life-threatening complication of esophageal stricture dilation. This usually occurs at the time of esophageal dilation, although it have been observed several days to weeks after dilation.

EXPECTED COURSE AND PROGNOSIS
Animals with fibrosing esophageal stricture generally have a fair to guarded prognosis. Many of these strictures recur despite repeated esophageal dilation. Animals with malignant stricture have a poor prognosis.


MISCELLANEOUS

ASSOCIATED CONDITIONS N/A

AGE RELATED FACTORS N/A

ZOONOTIC POTENTIAL None

PREGNANCY
Animals with esophageal stricture may have difficulty with pregnancy because of the anesthesia required and because malnutrition may develop.

SYNONYMS
• Esophageal narrowing
• Esophageal obstruction

SEE ALSO
Esophagitis
Gastroesophageal Reflux
Megaesophagus

ABBREVIATIONS N/A

References

Burk RL, Zawie DA, Garvey MS. Balloon catheter dilation of intramural esophageal strictures in the dog and cat: a description of the procedure and a report of six cases. Sem Vet Med Surg 1987;2:241-247.

Twedt DC. Diseases of the esophagus. In: Ettinger SJ, Feldman EC, eds. Textbook of veterinary internal medicine. Philadelphia: WB Saunders, 1994:1124-1142.

Author Robert J. Washabau

Consulting Editor Brent Jones

Diseases and Clinical Syndromes X