|
Reviewed Edgar Achkar, MD |
DYSPHAGIA |
|
DISORDERS CAUSED BY MUCOSAL INJURY PrevalencePathophysiology Signs
and
|
National Guidelines |
Dysphagia, a common symptom in those with esophageal disorders, may arise from a multitude of underlying causes. Dysphagia or difficulty swallowing refers a sensation of impairment of the normal progression of the bolus from the mouth into the stomach. Dysphagia should be distinguished from odynophagia or pain upon swallowing. Recognizing dysphagia and gauging its clinical significance appears simple. There are, however, several important points that may be brought up by the following questions:
- Is the patient complaining truly of dysphagia? In most cases, patients can express clearly symptoms of difficulty in swallowing. Alternative terms such as "food sticking" or "food moving down slowly into the chest" may assist in identifying those with dysphagia.
- Is the dysphagia for solids, liquids, or both? Mucosal lesions, benign or malignant, that produce a narrowing of the esophageal lumen will not usually interfere with the passage of liquid substances and dysphagia is limited to solid foods. On the other hand, disorders impairing esophageal peristalsis will cause difficulty with both solids and liquids.
- Is
the dysphagia intermittent or progressive? Structural lesions of the
lower esophagus such as rings and strictures, produce intermittent obstruction
related to the size of the bolus with often prolonged periods free of
symptoms. In motor disorders, on the other hand, dysphagia is insidious
and becomes progressively worse.
Proper clinical evaluation of dysphagia requires a detailed history.1 Multiple diagnostic techniques are available and their use depends upon the presenting clinical features. The initial test however is often a barium swallow or an endoscopic examination. The choice between these two techniques, as the most useful and least costly for the evaluation of dysphagia, is the subject of debate. In a patient who presents with intermittent solid dysphagia, suggesting a benign obstructing lesion such as peptic stricture or ring, starting with endoscopy is reasonable as it allows making the diagnosis and simultaneously treating the lesion by dilation. In cases of dysphagia to both solids and liquids and suspicion of a motor disorder, a barium swallow provides more useful information by evaluating esophageal peristalsis. The guidelines of the American Gastroenterological Association (AGA) support the choice of barium swallow in these cases, a recommendation that most clinicians would agree with.2
Various known causes
of esophageal disorders may be classified into four different groups:
- Disorders caused by mucosal injury
- Neoplastic disorders
- Anomalies of esophageal lumen
- Motor disorders
Mucosal injury is defined as mucosal damage resulting from an intrinsic or extrinsic agent capable of disrupting the integrity of the mucosa, leading to acute inflammation and potentially chronic inflammation with possible permanent scarring. The most common syndromes of mucosal injuries are:
- Acid reflux disease (GERD)
- Infectious esophagitis
- Radiation esophagitis
- Esophagitis due to caustic ingestion
- Pill esophagitis
Gastroesophageal reflux disease is discussed in detail in the chapter on acid peptic disorders.
While GERD is very prevalent, causing symptoms in 20% of the population at least once a week, other causes of mucosal injury are less frequent. Infectious esophagitis is rare in normal persons. In an immunocompromised individual, infection occurs today at a lesser rate than in the past because of better diagnostic and therapeutic techniques. Candida is the most frequent organism responsible for causing esophagitis. Radiation esophagitis is reported by some patients during treatment but long term lesions are not frequent. Caustic ingestions has been reduced dramatically since protection laws have been instituted. It is estimated that 5,000 cases occur each year in the U.S. The prevalence of pill induced esophagitis is not known. There are increasing number of cases reported but they constitute a small number compared to the innumerable pills ingested by the public.
Virtually all mucosal injuries are accompanied by inflammation with various degrees of severity including from erythema, frank ulcers with potential scarring and bleeding and strictures.
Infectious esophagitis
occurs almost always in immunocompromised patients such as post-transplant
patients or patients with cancer or AIDS. Predisposing factors include
diabetes, alcoholism, malnutrition and old age as well as treatment with
corticosteroids. Diseases leading to stasis such as achalasia may also
predispose to some infections. Radiation esophagitis occurs with radiation
therapy to the chest and mediastinum. It is dependent upon the total dose
administered as well as the time over which treatment is applied. Injury
by caustic ingestion is most commonly caused by alkali agents producing
burns or acid agents producing necrosis.
Pill esophagitis was first reported with tetracycline. Doxycline and other
tetracyclines account for the majority of cases but injuries have been
reported with other antibiotics, antiviral agents, nonsteroidal anti-inflammatory
drugs, potassium preparations and many other medications.3
There is some evidence that sustained release medications are more commonly
associated with injury. The lesion occurs most often between the junction
of the proximal and mid-esophagus at the point of impression by the aortic
arch or above the esophagogastric junction.
Mucosal injury may be asymptomatic or may manifest by dysphagia, odynophagia or chest pain. Patients whose nutrition may already be affected by their immunocompromised status and anorexia are further jeopardized by their inability to eat. Candida esophagitis is often asymptomatic and is discovered at endoscopy. Pill injury is accompanied by sudden onset of severe pain over one to three days. Pain is aggravated by eating.
The treatment of infectious esophagitis depends upon the isolation of the causative agent. In immunocompromised patients, multiple infections may co-exist. Treatment of candida esophagitis is best carried out with ketaconazole 200-400 mg/day or fluconazole 100 mg/day for 7 -14 days. Nystatin in oral solution may be effective in mild cases and in the absence of immunodeficiency. Viral infections respond in part to antiviral agents. Idiopathic ulcers of AIDS are treated with prednisone 40 mg/day with tapering over 4 weeks by 10 mg/week5 or thalidomide 200-300 mg/day over 4 weeks. The potential risk of birth defects limits the use of thalidomide.
In pill injury the offending medication should be withdrawn and antireflux therapy prescribed to prevent exacerbation of the injury. When odynophagia is pronounced, the use of topical anesthetic agents administered orally may help relieve the pain. In most cases, symptoms disappear within a few days and bleeding and perforation are rare. More importantly, pill injury should be prevented by encouraging patients to drink large amounts of fluid with their pills, to remain upright for 30 minutes after taking the pills and to avoid pills known to cause frequent injury particularly in patients with esophageal strictures or who are bedridden. These preventive measures are very important in elderly patients who tend to take multiple medications particularly at bedtime.
Chronic lesions caused by mucosal injury often lead to strictures. Strictures are managed by periodic dilations and antireflux treatment. In GERD, the use of potent acid suppressing agents has reduced the frequency with which dilation needs to be performed.
Most benign tumors of the esophagus are asymptomatic and discovered by chance during an examination obtained for other reasons. When symptomatic, benign tumors cause mostly dysphagia and, in some cases, chest pain and regurgitation. The most important issue is to differentiate them from malignant tumors.
A barium swallow will often determine if the lesion is intramural or mucosal. Endoscopy is often helpful in determining the tumor's nature (Figure 3). Some polyps appear on a long stalk and may be seen flopping into the lumen. Endoscopic examination will reveal intramural tumors as smooth protrusions covered by normal mucosa. Cysts appear as round and smooth. Mucosal lesions may sometimes ulcerate. Endoscopic ultrasound is helpful in distinguishing a leiomyoma from leiomyosarcoma. Unfortunately, when the tumor is large the differentiation is more difficult.
Small asymptomatic lesions require no treatment. Surgical enucleation is the treatment of choice for symptomatic intramural lesions or when intervention is necessary because malignancy cannot be ruled out with certainty. Polyps are treated by local resection.
Malignant tumors of the esophagus constitute the majority of esophageal tumors. Different types of tumors have been described and include:
- Squamous cell carcinoma
- Adenocarcinoma
- Sarcoma
- Lymphoma
- Primary melanoma
- Metastatic tumors (breast, lung, melanoma)
While there are differences between squamous cell carcinoma and adenocarcinoma in epidemiology, location and patterns of spread, both diseases tend to spread early outside the esophagus and both share a rather poor prognosis unless discovered early. For this reason, efforts are undertaken to detect early signs of cancer or precancer. A guideline of the American Society of Gastrointestinal Endoscopy lists the conditions for which screening is recommended for early detection7:
Screening recommended (every 1-3 years):- Barrett's esophagus
- Caustic ingestion: start 15-20 years after injury
- Tylosis: Start at age 30
- Achalasia
Carcinoma of the esophagus should be suspected in any individual with recent onset dysphagia particularly after the age of 50. A long history of reflux diseases raises the possibility of carcinoma arising in Barrett's esophagus especially in white men. The following diagnostic modalities are used in the evaluation of malignant neoplasms:
- Barium swallow
- Endoscopy
- Computerized tomography (CT)
- Endoscopic ultrasound (EUS)
- Bronchoscopy
Barium swallow gives an indication of tumor location and size (Figure 4). Endoscopy determines the size of the esophageal lumen (Figure 5). Biopsy and cytologic brushings establish the tumor's histologic type. The central issue, at that point, is the appropriateness of surgical intervention. The decision to operate is based on tumor staging. Both squamous cell carcinoma and adenocarcinoma are staged according to the TNM system (Tumor invasion, lymph nodes and metastasis). (Table 1) EUS is more sensitive than CT but a combination of both improves staging's accuracy.8
Curative Treatment:
When full evaluation reveals a favorable stage and the patient's general condition is not a contraindication to surgery, tumor resection represents the most promising treatment. Surgical resection is indicated when the lesion is considered curable. Combined chemo and radiotherapy followed by surgery is offered to patients with local extension. Even in adenocarcinoma which is less sensitive to chemo and radiotherapy, combined treatment improves prognosis. The best chance of significant survival in esophageal cancer resides in a multidisciplinary approach in institutions possessing good experience in gastroenterology, thoracic surgery, chemotherapy and radiation oncology.
The ASGE guideline9 outlines the advantages of and the treatment approach for esophageal cancer with an algorithm (Figure 6).
Palliative Treatment:
When surgery is ruled out because of tumor extension or complications and in cases of tumor recurrence, several palliative methods are available. Esophageal cancer is often diagnosed at an advanced incurable stage and when patients present with dysphagia, 50% of the lumen may already be occluded.
Palliation methods include radiotherapy and the following endoscopic modalities:
- Periodic dilation
- Esophageal stenting
- Photodynamic ablation
- Laser ablation
- Endoscopic mucosal resection
Endoscopic techniques have various rates of success and they all carry a risk of complications including perforation, infection and bleeding as well as worsening of the initial symptoms. In late stages and in patients whose dysphagia is insurmountable, insertion of a gastrostomy feeding tube is often necessary.
Rings are concentric narrowings of the lumen usually seen in the lower esophagus. The B-ring or muscular ring occurs at the junction of the tubular portion of the esophagus and the most distal part called the vestibule. The ring is often described by radiologists but is rarely symptomatic. The A or mucosal ring occurs most distally at the esophagogastric junction and usually in association with a hiatal hernia. Also known as Schatzki's ring10, it deserves particular attention because it is often symptomatic (Figure 7).
A Schatzki's ring consists of esophageal mucosa and submucosa. This ring is almost always associated with the presence of a hiatal hernia. While it is histologically and probably pathogenetically different from esophageal peptic strictures, the association of a lower esophageal ring with gastroesophageal reflux is frequent. In addition, distinguishing one from the other endoscopically is sometimes difficult. Therefore, many clinicians manage esophageal rings as they do strictures. The PlummerVinson and the Paterson Kelly syndromes refer to the association of webs with iron deficiency anemia and other oropharyngeal abnormalities. These associations are rarely described today and the terms have largely been abandoned.
An esophageal diverticulum is a sac protruding from the esophageal wall and containing all layers of the esophagus. Esophageal diverticula may be congenital or acquired. The simplest way to classify them is according to anatomy:
- Zenker's diverticula
- Mid-esophageal diverticula
- Epiphrenic diverticula
- Intramural pseudodiverticulosis
Zenker's diverticulum or pharyngoesophageal diverticulum occurs in a location proximal to the esophagus above the upper esophageal sphincter. The diverticulum bulges posteriorly and its size increases over time. The most widely accepted mechanism for a Zenker's diverticulum is a functional disturbance of the hypopharynx. The most popular explanation is an incoordination between the pharynx and the cricopharyngeus muscle called "cricopharyngeal achalasia." Most recent evidence however suggests that the diverticulum occurs because of reduced compliance of the upper sphincter rather than because of incoordination.12 Mid-esophageal diverticula have been divided into traction and pulsion diverticula. This distinction has no practical value. The exact cause of a mid-esophageal diverticulum is not known but the condition has been associated with scarring and various esophageal motor abnormalities. Epiphrenic diverticula are almost always the result of an esophageal motor abnormality, namely an incoordination between the distal esophagus and the lower esophageal sphincter.13
Esophageal intramural pseudodiverticulosis is characterized by numerous, minute, flask-like outpouchings along the esophageal wall.14 They can be segmental or generalized. They are associated with strictures, carcinoma, candidiasis and motor abnormalities (Figure 9).
Symptomatic Zenker's diverticula can be treated by surgical excision. Newer treatments are applied endoscopically. A transection is made to create a communication between the diverticulum and the esophagus allowing the diverticulum to drain into the esophagus. This technique can be carried out with or without the assistance of laser.15,16 Most surgeons agree that whatever the surgical technique, a myotomy of the cricopharyngeus muscle is necessary to prevent recurrence of the diverticulum. Mid-esophageal diverticula are treated by surgical excision. For an epiphrenic diverticulum the goal of therapy should be to treat the underlying motor disorder with the hope of avoiding further enlargement of the diverticulum. In the absence of achalasia, a long esophagomyotomy is recommended but published results involve a small number of patients. Intramural pseudodiverticulosis requires treatment of the underlying infection or obstruction with dilatation in the case of a distinct obstructing area.
- AGA
technical review on treatment of patients with dysphagia caused by benign
disorders of the distal esophagus. Gastroenterology. 1999;117:233-254.
- American
Gastroenterological Association medical position statement on treatment
of patients with dysphagia caused by benign disorders of the distal
esophagus. Gastroenterology. 1999;117:229-232.
- Kikendall
JW. Pill-induced injury in The Esophagus 3rd Edition. Castell DO, Richter
JE eds. Lippincott, Williams, and Wilkins, Philadelphia, 1999. Pp527-537.
- Wilcox
CM, Schwartz DA. Endoscopic pathologic correlates of Candida esophagitis
in acquired immunodeficiency syndrome. Dig Dis Sci. 1996;41:1337-1345.
- Wilcox
CM, Schwartz DA. Comparison of two corticosteroid regimens for the treatment
of idiopathic esophageal ulcerations associated with HIV infection.
Am J Gastroenterol. 1994;89:2163.
- Fleischer
DE, Haddad NG. Neoplasms of the esophagus in The Esophagus 3rd Edition.
Castell DO, Richter JE eds. Lippincott, Williams, and Wilkins, Philadelphia,
1999. Pp235-257.
- The
role of endoscopy in the surveillance of premalignant conditions of
the upper gastrointestinal tract. Gastrointest Endosc. 1998;48:663-668.
- Byrne
MF, Jowell PS. Gastrointestinal imaging: Endoscopic ultrasound. Gastroenterology.
2002;122:1631-1648.
- The
role of endoscopy in the assessment and treatment of esophageal cancer.
Gastrointest Endosc. 2003; 57:817-822.
- Schatzki
R. The lower esophageal ring. Long term follow-up of asymptomatic rings.
Am J Roentgenol Radiat Ther Nucl Med.1963;90:805.
- Ekberg
O, Nylander G. Cineradiography of the pharyngeal phase of deglutition
in 250 patients with dysphagia. Br J Radiol. 1982;55:258-262.
- Kahrilas
PJ, Dodds WF, Dent J, Logemann JA, Shaker R. Upper esophageal sphincter
function during deglutition. Gastroenterology. 1988;95:52-62.
- Bruggeman
LL, Seaman WB. Epiphrenic diverticula. An analysis of 80 cases. Am
J Roentgenol. 1973;119:266-276.
- Boyd
RM, Bogoch A, Grieg JH, et al. Esophageal intramural pseudodiverticulosis.
Radiology. 1974;113:267-270.
- Scher
RL, Richtsmeier WJ. Long-term experience with endoscopic staple-assisted
esophagodiverticulostomy for Zenker's diverticulum. Laryngoscope.
1998;108:200-205.
- Stoeckli SJ, Schmid S. Endoscopic stapler-assisted diverticuloesophagostomy for Zenker's diverticulum: Patient satisfaction and subjective relief of symptoms. Surgery. 2002;131:158-62




